How is hematocrit determined using microhematocrits. What are the key aspects of quality control in hematology laboratories. How do Levey-Jennings charts contribute to maintaining accuracy in blood testing procedures. What role does competency assessment play in ensuring reliable laboratory results.

The Importance of Hematocrit in Clinical Diagnostics

Hematocrit, often abbreviated as HCT, is a crucial measurement in hematology that provides valuable information about a patient’s blood composition. It represents the volume percentage of red blood cells in blood, serving as an essential indicator of various health conditions.

Why is hematocrit determination so significant? Hematocrit levels can reveal:

• Anemia or polycythemia
• Dehydration or overhydration
• Bone marrow disorders
• Nutritional deficiencies
• Response to certain medications

Given its importance, accurate hematocrit measurement is paramount in clinical laboratories.

Microhematocrits: A Precise Method for Hematocrit Determination

Microhematocrits have revolutionized the way hematocrit is measured in modern laboratories. This technique involves using small capillary tubes to separate red blood cells from plasma through centrifugation. But how exactly does this process work?

The microhematocrit procedure typically follows these steps:

1. A small blood sample is collected in a capillary tube
2. The tube is sealed at one end
3. It’s then centrifuged at high speed for a specific duration
4. After centrifugation, the separated layers are measured
5. The ratio of red blood cells to total blood volume is calculated

This method offers several advantages over traditional hematocrit determination techniques, including increased precision and the need for only a small blood sample.

Quality Control Measures in Hematology Laboratories

Maintaining high standards of accuracy and reliability in hematology testing is crucial. Laboratories employ various quality control (QC) measures to ensure consistent and dependable results. What are some key QC procedures used in hematology labs?

Essential quality control measures include:

• Regular instrument calibration and maintenance
• Use of control samples with known values
• Participation in external quality assessment programs
• Implementation of standard operating procedures (SOPs)
• Continuous staff training and competency assessments

These measures work together to minimize errors and maintain the highest standards of laboratory performance.

Levey-Jennings Charts: A Powerful Tool for Laboratory Quality Assurance

Levey-Jennings charts play a pivotal role in monitoring and maintaining the quality of laboratory tests, including hematocrit determinations. These statistical control charts help visualize test performance over time, allowing for early detection of analytical problems.

How do Levey-Jennings charts work? They plot control sample results against time, typically using these elements:

• A central line representing the mean or target value
• Upper and lower control limits (usually set at ±2 or ±3 standard deviations)
• Individual data points for each control measurement

By analyzing the patterns on these charts, laboratory staff can quickly identify trends, shifts, or other irregularities that may indicate a need for corrective action.

Implementing Levey-Jennings Charts in Different Laboratory Sections

The use of Levey-Jennings charts extends beyond hematology to other laboratory disciplines. For instance, CD4 count testing, chemistry analyses, and even specialized tests like hemocytometer fluid counts benefit from this quality control tool. Each section may have specific procedures for creating and interpreting these charts, tailored to the unique aspects of their tests.

Competency Assessment: Ensuring Skilled Laboratory Personnel

The accuracy of laboratory results heavily depends on the competence of the staff performing the tests. Competency assessment is a systematic process to evaluate and ensure that laboratory personnel possess the necessary skills and knowledge to perform their duties effectively.

What does a typical competency assessment involve? Key components often include:

• Direct observation of routine procedures
• Review of patient test results
• Written or oral examinations
• Practical skills demonstrations
• Proficiency testing performance review

Regular competency assessments help maintain high standards of performance and identify areas where additional training may be needed.

The Role of Standard Operating Procedures (SOPs) in Laboratory Quality Management

Standard Operating Procedures (SOPs) are detailed, written instructions that document routine laboratory operations. They play a crucial role in maintaining consistency, quality, and regulatory compliance in clinical laboratories. But why are SOPs so important in hematology and other laboratory disciplines?

SOPs serve several critical functions:

• Ensuring uniformity in test performance
• Facilitating staff training and competency assessment
• Providing a reference for troubleshooting
• Supporting regulatory compliance
• Aiding in quality assurance and improvement efforts

From microhematocrit procedures to complex analytical techniques, well-written SOPs are the backbone of reliable laboratory operations.

External Quality Assessment: Benchmarking Laboratory Performance

External Quality Assessment (EQA) programs, also known as proficiency testing, are an essential component of a comprehensive laboratory quality management system. These programs allow laboratories to compare their performance with peer institutions, providing valuable insights and opportunities for improvement.

How does EQA work in practice? The process typically involves:

• Receiving samples with unknown values from an EQA provider
• Analyzing these samples using routine laboratory procedures
• Submitting results to the EQA provider
• Receiving a performance report comparing results to peer laboratories
• Implementing corrective actions if necessary

Participation in EQA programs not only helps laboratories maintain high standards but also builds confidence in the accuracy and reliability of their test results.

Specialized EQA Programs in Hematology

In hematology, specialized EQA programs may focus on specific tests or techniques. For example, there are dedicated programs for evaluating manual hemocytometer fluid counts or urinalysis surveys. These specialized assessments help laboratories fine-tune their skills in particular areas of hematology testing.

Instrument Calibration and Maintenance: Ensuring Accurate Results

The accuracy of hematocrit determinations and other laboratory tests relies heavily on properly calibrated and well-maintained instruments. Regular calibration and maintenance procedures are crucial for ensuring reliable results and extending the lifespan of laboratory equipment.

What does effective instrument management entail? Key aspects include:

• Routine calibration checks using certified reference materials
• Regular preventive maintenance according to manufacturer recommendations
• Proper documentation of all calibration and maintenance activities
• Staff training on instrument operation and troubleshooting
• Implementing a system for tracking instrument performance over time

By prioritizing instrument calibration and maintenance, laboratories can minimize downtime, reduce errors, and ensure consistent, high-quality test results.

The Importance of Thermometer Calibration

While often overlooked, accurate temperature measurement is critical in many laboratory procedures, including certain hematology tests. Thermometer calibration verification is an essential part of instrument management. Proper calibration ensures that temperature-sensitive processes, such as incubations or reagent storage, are performed under optimal conditions, contributing to the overall accuracy of test results.

Evaluating Patient Test Results: Beyond the Numbers

Interpreting laboratory results, including hematocrit values, requires more than just looking at numbers. Laboratory professionals must consider various factors that can influence test outcomes and their clinical significance. How do laboratories ensure accurate interpretation of patient results?

Key considerations in evaluating patient test results include:

• Understanding the clinical context and patient history
• Recognizing the limitations and potential interferences of each test
• Analyzing trends in serial measurements
• Correlating results with other relevant laboratory and clinical findings
• Utilizing decision support tools and expert systems when available

By taking a comprehensive approach to result evaluation, laboratories can provide clinicians with more meaningful and actionable information to guide patient care.

The Role of Flags, Codes, and Messages in Result Reporting

Many modern hematology analyzers generate flags, codes, or messages to alert laboratory staff to potential abnormalities or analytical issues. These automated alerts can help streamline the review process and ensure that critical or unexpected results receive prompt attention. However, it’s crucial for laboratory professionals to understand the significance of these flags and how to respond appropriately to ensure accurate result reporting.

Developing a Comprehensive Quality Management Plan

A well-structured quality management plan is essential for maintaining high standards in clinical laboratories. This plan serves as a roadmap for implementing and monitoring quality assurance measures across all aspects of laboratory operations. But what elements should a comprehensive quality management plan include?

Key components of an effective quality management plan typically encompass:

• Clear quality objectives and policies
• Detailed procedures for quality control and assurance
• Staff roles and responsibilities in quality management
• Protocols for document control and record-keeping
• Processes for identifying and addressing non-conformities
• Continuous improvement initiatives
• Internal audit procedures

By developing and adhering to a comprehensive quality management plan, laboratories can ensure consistent, high-quality performance across all their testing services, including hematocrit determinations.

Adapting Quality Management Plans to Specific Laboratory Needs

While general principles of quality management apply broadly, each laboratory must tailor its plan to its specific circumstances, test menu, and regulatory requirements. For instance, a hematology laboratory focusing on specialized tests like microhematocrits may need to incorporate additional quality measures specific to these procedures. Regularly reviewing and updating the quality management plan ensures it remains relevant and effective in maintaining laboratory excellence.

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(PDF) Hematocrit (HCT)

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-.

Hematocrit (HCT)

Authors

Himel Mondal ; Deepa P. Budh .

Affiliations

Bhima Bhoi Medical College and Hospital, Balangir

Saurashtra University – MP Shah Medical College

Last Update: February 20, 2020.

Introduction

The term “hematocrit (HCT)” originated from English “hemato-“ and Greek “krites. ” HCT measures the volume of

packed red blood cells (RBC) relative to whole blood. Hence, it is also known and reported as a packed cell volume

(PCV). It is a simple test to identify conditions like anemia or polycythemia and also to monitor response to the

treatment. A glass tube and a centrifuge machine are sufficient to measure HCT. After centrifugation, the component

of blood separates into three distinct parts. From below upwards, the layers are – a layer of red blood cells (RBC), a

layer of white blood cells(WBC) and platelets, and a layer of plasma at the top. This method of determining HCT by

Wintrobe hematocrit tube is known as the “macro-hematocrit” method.[1] A Wintrobe tube is a narrow glass tube

measuring 110-mm-long, with graduation from 0 to 100 mm in both ascending and descending order. This method

has been succeeded by the “micro-hematocrit” method which uses a small capillary tube instead of a Wintrobe

hematocrit tube. It requires less quantity of blood as well as less time requirement for the testing procedure. It is

beneficial for patients from whom blood collection is difficult (e.g., pediatric patients/hypovolemia). However, the

principle of the test remains the same as the “macro-hematocrit” method. HCT calculation is by dividing the lengths of

the packed RBC layer by the length of total cells and plasma. As it is a ratio, it doesn’t have any unit. Multiplying the

ratio by 100 gives the accurate value, which is the accepted reporting style for HCT. A normal adult male shows an

HCT of 40% to 54% and female shows 36% to 48%.[2] Though these two methods are still in use in some settings of

primary care and medical teachings, they are widely replaced in the majority of settings by an automated analyzer,

where HCT reports get generated along with the complete blood count.

Specimen Requirements and Procedure

For the macro-hematocrit method, venous blood is taken as a random sample (i. e., no special precautions needed)

maintaining proper aseptic precautions. The blood is either collected in a commercially available vacutainer containing

ethylenediaminetetraacetic acid (EDTA) or in a vial/test tube with EDTA where vacutainer is not available[3]. For the

microhematocrit method, the blood requirement is less, and single finger-prick blood is sufficient. Heparin filled

capillary tube may is used to collect blood. However, if there is available blood with anticoagulant for other

hematologic tests, a capillary tube without heparin can be used. For measurement of HCT in automated hematologic

cell counter, blood with anticoagulant used for CBC is necessary.

Testing Procedures

The macro-hematocrit method uses a Wintrobe hematocrit tube, a centrifuge machine, and a Pasteur pipette. Blood is

filled in Wintrobe hematocrit tube up to 100 mm mark by the help of Pasteur pipette. Care is taken not to leave any

bubble in the blood column. For this, the tube is filled slowly with the tip of the pipette being always below the highest

position of the blood column. Then, the tube gets placed in the centrifuge machine. When testing a single specimen,

another blood-filled Wintrobe hematocrit tube is kept on the opposite holder to counterbalance. The spin setting is

3000 rpm for 30 min. After completion of the centrifugation, the tube is taken out, and RBC column height is reported

as HCT. During the reporting, special precaution is necessary to omit the buffy coat, which is a combination of WBC

and platelets. This layer should not be included in the HCT, as it may lead to false positive results.

For the microhematocrit method, after filling the blood in a capillary tube, the two ends of the tube (commonly 75 mm

long, 1 mm diameter) are sealed with clay sealant or heat. Then, it is centrifuged at a rate of 11000 to 12000 rpm for 4

1 2

1

2

Hematocrit (HCT) – StatPearls – NCBI Bookshelf https://www. ncbi.nlm.nih.gov/books/NBK542276/?report=printable

Hematocrit | Encyclopedia.com

Definition
Purpose
Precautions
Description
Aftercare
Risks
Normal results

The hematocrit is a test that measures the percentage of blood that is comprised of red blood cells.

The hematocrit is used to screen for anemia, or is measured on a person to determine the extent of anemia. An anemic person has fewer or smaller than normal red blood cells. A low hematocrit, combined with other abnormal blood tests, confirms the diagnosis. The hematocrit is decreased in a variety of common conditions including chronic and recent acute blood loss, some cancers, kidney and liver diseases, malnutrition, vitamin B₁₂ and folic acid deficiencies, irondeficiency, pregnancy, systemic lupus erythematosus, rheumatoid arthritis and peptic ulcer disease. An elevated hematocrit is most often associated with severe burns, diarrhea, shock, Addison’s disease, and dehydration, which is a decreased amount of water in the tissues. These conditions reduce the volume of plasma water causing a relative increase in RBCs, which concentrates the RBCs, called hemoconcentration. An elevated hematocrit may also be caused by an absolute increase in blood cells, called polycythemia. This may be secondary to a decreased amount of oxygen, called hypoxia, or the result of a proliferation of blood forming cells in the bone marrow (polycythemia vera).

Critically high or low levels should be immediately called to the attention of the patient’s nurse or doctor. Transfusion decisions are based on the results of laboratory tests, including the hematocrit. Generally, transfusion is not considered necessary if the hematocrit is above 21%. The hematocrit is also used as a guide to how many transfusions are needed. Each unit of packed red blood cells administered to an adult is expected to increase the hematocrit by approximately 3% to 4%.

Fluid volume in the blood affects hematocrit values. Accordingly, the blood sample should not be taken from an arm receiving IV fluid or during hemodialysis. It should be noted that pregnant women have extra fluid, which dilutes the blood, decreasing the hematocrit. Dehydration concentrates the blood, which increases the hematocrit.

In addition, certain drugs such as penicillin and chloramphenicol may decrease the hematocrit, while glucose levels above 400 mg/dL are known to elevate results. Blood for hematocrit may be collected either by finger puncture, or sticking a needle into a vein, called venipuncture. When performing a finger puncture, the first drop of blood should be wiped away because it dilutes the sample with tissue fluid. A nurse or phlebotomist usually collects the sample following cleaning and disinfecting the skin at the site of the needle stick.

KEY TERMS

Anemia— A lack of oxygen carrying capacity commonly caused by a decrease in red blood cell number, size, or function.

Dehydration— A decreased amount of water in the tissues.

Hematocrit— The volume of blood occupied by the red blood cells, and expressed in percent.

Hypoxia— A decreased amount of oxygen in the tissues.

Polycythemia— A condition in which the amount of RBCs are increased in the blood.

Blood is made up of red blood cells, white blood cells (WBCs), platelets, and plasma. A decrease in the number or size of red cells also decreases the amount of space they occupy, resulting in a lower hematocrit. Conversely, an increase in the number or size of red cells increases the amount of space they occupy, resulting in a higher hematocrit. Thalassemia minor is an exception in that it usually causes an increase in the number of red blood cells, but because they are small, it results in a decreased hematocrit.

The hematocrit may be measured manually by centrifugation. A thin capillary tube called a microhematocrit tube is filled with blood and sealed at the bottom. The tube is centrifuged at 10,000 RPM (revolutions per minute) for five minutes. The RBCs have the greatest weight and are forced to the bottom of the tube. The WBCs and platelets form a thin layer, called the buffy coat, between the RBCs and the plasma, and the liquid plasma rises to the top. The height of the red cell column is measured as a percent of the total blood column. The higher the column of red cells, the higher the hematocrit. Most commonly, the hematocrit is measured indirectly by an automated blood cell counter. It is important to recognize that different results may be obtained when different measurement principles are used. For example, the microhematocrit tube method will give slightly higher results than the electronic methods when RBCs of abnormal shape are present because more plasma is trapped between the cells.

Discomfort or bruising may occur at the puncture site. Pressure to the puncture site until the bleeding stops reduces bruising; warm packs relieve discomfort. Some people feel dizzy or faint after blood has been drawn, and lying down and relaxing for awhile is helpful for these people.

Other than potential bruising at the puncture site, and/or dizziness, there are no complications associated with this test.

Normal values vary with age and sex. Some representative ranges are:

• at birth: 42-60%
• six to 12 months: 33-40%
• adult males: 42-52%
• adult females: 35-47%

Resources

BOOKS

Chernecky, Cynthia C. and Barbara J. Berger. Laboratory Tests and Diagnostic Procedures. 3rd ed. Philadelphia: W. B. Saunders Company, 2001.

Kee, Joyce LeFever. Handbook of Laboratory and Diagnostic Tests. 4th ed. Upper Saddle River, NJ: Prentice Hall, 2001.

Kjeldsberg, Carl R. Practical Diagnosis of Hematologic Disorders. 3rd ed. Chicago: ASCP Press, 2000.

ORGANIZATIONS

American Association of Blood Banks. 8101 Glenbrook Road, Bethesda, Maryland 20814. (301) 907-6977. Fax: (301) 907-6895. http://www.aabb.org.

Victoria E. DeMoranville

Mark A. Best

Hematocrit (HCT) conversion to %, L/L, Proportion of 1.0, volume fraction. Online converter from conventional units to SI units

The purpose of the hematocrit or packed cell volume (PCV) test is to determine the percentage of red blood cells in whole blood. The hematocrit is reported as a percentage because it is the proportion of red blood cells compared to the amount of plasma in whole blood. The term “hematocrit” literally means to separate blood. A sample of blood is placed in a tube that contains an anticoagulant, which prevents clotting. The sample is mixed, and three distinct layers will separate out. The bottom layer represents the hematocrit value and is composed of red blood cells, approximately 45% of the total blood volume, with variations allowed for men and women. The middle layer is a thin, whitish layer called the buffy coat, approximately 1% of the blood volume, which is made up of white blood cells and platelets . The upper layer is the liquid plasma, which comprises the remainder of the total blood volume.

Normal Range

Men 42-52%

Women 37-47% (in pregnancy : >33%)

Children 30-42%

Newborns 44-64%

Since the hematocrit is the percentage of red blood cells in whole blood, a decrease in hematocrit values is an indication of some type of anemia. Therefore, anything that causes a decrease in the number of red blood cells will result in a decrease in the hematocrit. Blood loss, conditions where there is increased destruction of red blood cells, leukemia, and diseases that interfere with red blood cell production will exhibit a low hematocrit. It must also be noted that overhydration, or an increase in plasma volume for any reason, can result in a relative decreased hematocrit value. An apparent increase in the hematocrit must be closely analyzed. Since the hematocrit is reported as a percentage of red blood cells to blood volume, any decrease in the volume of plasma would result in a mathematical increase in the hematocrit. Therefore, if the patient has lost blood plasma, the blood will be very concentrated and the hematocrit will be increased. When an increase in hematocrit is related to the increase in the actual number of red blood cells, erythrocytosis or polycythemia is the result.

Interfering Circumstances. Factors that can influence hematocrit results include age, pregnancy, gender, and living in high altitudes .

Two different hematocrit detection methods: Different methods, different results? | BMC Research Notes

Measurement of hemoglobin or hematocrit is of major importance in contemporary patient care. Anemia or traumatic/surgical blood loss might require transfusion of red blood cells (RBC) to increase oxygen delivery and counteract tissue hypoxia. However, clear transfusion triggers are difficult to define because there is no clear delineation between risk and benefit. To date, at least 3 large randomized controlled trials have compared restrictive transfusion triggers to a more liberal transfusion regime in critically ill adult patients[1], pediatric intensive care patients[2] and premature infants [3]. All three studies showed that a restrictive transfusion regime reduced RBC transfusion requirements without increasing morbidity and mortality. In this context, hemoglobin concentrations ranging from 7-9 g/dl were compared to 10-12 g/dl.

In this context, we have observed a discrepancy between the hematocrit values determined by routine arterial blood gas analysis compared to routine analysis in our central laboratory. Therefore, we analyzed 250 blood samples taken from 50 critically ill patients. The aims were (1) to compare two different hematocrit-testing methods routinely used in our intensive care unit (ICU) and hospital (central laboratory) and (2) to determine whether these two methods might provide different transfusion triggers.

In accordance with the principles outlined by the World Medical Association declaration of Helsinki and following approval by the local Ethics Committee which waived the need for written informed consent for this post hoc data analysis, patient data from 50 patients treated on our intensive care unit from November 2007 to March 2008 were analyzed retrospectively. A total of 50 critically ill patients treated consecutively in our department were included irrespective of hemodynamic stability or diagnosis for the comparison of the two methods.

Blood was drawn daily, usually, at 6 a.m. for routine laboratory analysis, including 2 hematograms performed with 2 different methods. To compare hematocrit values determined by these two different methods of analysis, 250 paired hematocrit values (data of 50 patients over 5 consecutive days resulting in 250 paired samples) were considered. The patients were assigned to 2 different groups depending on the transfusion targets set during ICU treatment. A total of 20 patients with severe traumatic brain injury, severe burns, following reconstructive surgery or with cardiac ischemia had a hematocrit target of 28%. The other 30 patients had a target hematocrit of 24%.

On the ICU arterial blood samples were routinely drawn in 4 to 6 hour intervals to control paO₂, paCO₂, hematocrit, glucose or potassium serum levels, required to optimize ventilatory settings, guide transfusions, and adapt intravenous infusion of insulin or potassium. These blood samples were analysed by the nurses using the commercially available blood gas analyzer ABLflex 800 (Radiometer Medical, Copenhagen, Denmark; http://www. Radiometer.com) located on our ICU. Blood was drawn daily, usually, at 6 a.m. for routine laboratory analysis. Among others, differential blood count including analysis of hemoglobin/hematocrit was performed. As a standardized pre- analytic procedure[4, 5], at least 2 ml of blood were discarded to prevent hemodilution by infused fluids before withdrawing blood for the actual analysis using specialized syringes, i.e., the syringe for the ABLflex 800 (Arterial Blood sampler 1.7 ml, Radiometer Copenhagen, Denmark) and vacutainers (BD Vacutainer^® K2E 5.4 mg, BD-Plymouth, PL67BP, UK) for the ADVIA 2120.

Method 1: ABLflex 800

The specimen is drawn from the syringe into the cuvette within the gas analyzer maintained at 37°C. Thereafter, one microliter of the specimen is hemolized via ultrasound (30 kHz). Hemoglobin content is assessed spectrophotometrically using 128 different wave lengths (478 to 672 nm). The light is transmitted via glass-fiber optics through a diffraction gating, which diffracts the light into 128 single wavelengths. The detecting device consists of 128 photo diodes. According to the equation of Lambert-Beer hemoglobin content (ctHb) of the blood sample is determined. Based on the ctHb the hematocrit (hct) is calculated via an internal algorithm.

Method 2: ADVIA 2120

(Siemens Medical Solutions Diagnostics, Zurich, Switzerland, http://www.diagnostics.siemens.com): This device uses 2 sequential methods of haemoglobin measurement:

1. (1)

   Flow cytometry: In a first step red blood cells are applied to iso-volumetric sphering and partial fixation. Then a second reagent encases the sample stream and the entire specimen passes through a flow cell. A red laser then measured cell volume and intracellular haemoglobin concentration. The amount of light scattered at low angle (2-3°) is dependent on the cell volume and the high angle (5-15°) is related to the refractive index of the cell, reflecting the haemoglobin concentration for red blood cells (CHCM). The haematocrit then is calculated.

2. (2)

   A cyanide-free reagent (borate solution) and a surfactant (N, N,-dimethyllaurylamine N-oxide) cause haemolysis and facilitate the oxidation of haeme iron to Fe 3⁺. Because of the alkaline pH of the reagent haemoglobin loses most of its salt bridges. The ligated heme groups are solubilized by surfactant micelles to generate a green end-product which can be detected photometrically[6].

During analysis both values for haemoglobin determined by 1 and 2 are compared by an internal algorithm. In case of a predefined discrepancy the haemoglobin value is corrected in respect to the colorimetric method which is considered as the “gold standard” [7].

Our null hypothesis was that the two different methods (ABLflex 800 and ADVIA 2120) were equal and did not provide different transfusion triggers. The alternative hypothesis was that the ABLflex 800 method is not equal to the ADVIA 2120 method.

Bland-Altman analysis corrected for repeated measurements [8, 9] and Cohen’s kappa statistics [10] were used to compare the two methods (Statview 4.5, abacus concepts, Berkeley, CA, USA). Cohen’s kappa statistics compares the observations of two different methods and therefore results in 4 possible cases: +/+, +/-, -/+ and -/-. There is an agreement of the methods in the cases of +/+ and -/- (i.e. “transfused”/”transfused” and “not transfused”/”not transfused”) and there is no agreement in the cases +/- and -/+ (i.e.,”transfused”/”not transfused” and “not transfused”/”transfused”), respectively. With kappa ≤ 0.4 the agreement is poor, if kappa is between 0.4 and 0.75 agreement is fair and kappa ≥ 0.75 reflects excellent agreement between these two methods.

Comparisons between groups were calculated either with Chi-square test, with a nonparametric Mann-Whitney test or ANOVA log rank test (Statview 4. 5, abacus concepts, Berkeley, CA, USA). Statistical significance level was accepted with p < 0.05.

The investigated 50 patients were grouped according to the pre- defined transfusion triggers (24 and 28%) used on our intensive care unit for different illnesses, resulting in 30 patients within the 24-%-hematocrit-group and 20 patients in the 28-%-hematocrit-group. As depicted in table 1 these two hematocrit target groups consist of heterogeneous patients with different leading diagnosis which, in turn, dictated different treatment concepts and different transfusion triggers. Consequently, these 2 groups are not comparable. Serum levels of lactate and body temperature were significantly different in the 2 groups (p = 0.02 and 0.04, respectively). Hospital mortality was also significantly different (p = 0.03).

Table 1 Baseline and clinical characteristics

Bland-Altman analysis for repeated measurements of all patients showed a good agreement with a bias of +1. 39% and 2 standard deviations (2 SD) of ± 3.12% (figure 1). Thus, the ABL800 flex method showed an approximately 1.4% higher hematocrit than the ADVIA 2120 method. Bias for each group was not statistically different (1.11 ± 1.83% in the 24%-hematocrit-group vs. 1.70 ± 1.24% in the 28%-hematocrit-group, p = 0.26).

Figure 1

Bland-Altman analysis for repeated measurements of all patients showed a good agreement with a bias of +1.39% and 2 standard deviations (2 SD) of ± 3.12%. The lower and upper limits of agreement (bias ± 2 SD) are -1.73 and 4.51%, respectively. Thus, the ABLflex 800 method showed elevated hematocrit by approximately 1.4%.

According to the targeted transfusion triggers of 24% and 28% two kappa statistical analysis were performed in 30 patients with a transfusion trigger set at hematocrit of 24% and 20 patients with a hematocrit transfusion trigger of 28%. In those patients with a predefined hematocrit target of 24% (n = 150 values) both methods showed a significant correlation of r² = 0. 87 (figure 2). Kappa of 0.56 indicated a fairly good agreement of the methods, i.e., values located within the lower field below 24% (square III) reflect patients who needed to be transfused according to both methods of analysis and square I depicts those patients in whom transfusions were not required, regardless of analytical procedure. In contrast, square II shows 34 patients (22.7%) who would have been transfused according to the hematocrit values determined by the central laboratory. According to the blood gas analysis, however, these patients would not have been transfused.

Figure 2

In 30 patients with a predefined hematocrit target of 24% (n = 150 values) both methods showed a significant correlation of r²= 0.87 and kappa was 0.56, indicating a fair agreement of the methods. Values located within the lower field below 24% (square III) reflect patients who need to be transfused according to both methods of analysis; in contrast, square II shows 34 patients (22. 7%) who would have been transfused according to the hematocrit values determined by the central laboratory.

In patients with predefined hematocrit target of 28% (n = 100 values) both methods also correlated well with r² = 0.8 (figure 3). Kappa of 0.58 also reflected a fairly good agreement of these two methods, i.e., values located within square III below 28% reflected patients requiring RBC transfusions according to both methods of analysis. Square II shows 21 patients (21%) in whom hematocrit determined by the central laboratory would have suggested RBC transfusion while blood gas analysis would not have indicated RBC transfusion. In square I none of the patients would be transfused, regardless of analytical procedure.

Figure 3

In 20 patients with predefined hematocrit target of 28% (n = 100 values) both methods correlated well with r²= 0.8, a kappa of 0.58 reflected a fair agreement of the methods. Values located within square III below 28% reflect patients who require RBC transfusions according to both methods of analysis, whereas square II shows 21 patients (21%) in whom hematocrit determined by the central laboratory would have suggested RBC transfusion while blood gas analysis would not have indicated RBC transfusion.

According to the present analysis, ADVIA 2120 and ABLflex 800 provide similar hematocrit values. Nevertheless, values close to the lower transfusion/hematocrit threshold will be strongly influenced by the employed analytical method. Thus, these methodological differences must be considered in addition to the defined transfusion trigger to standardize transfusion practice within the individual ICU/hospital and across different hospitals in multi-center trials [1]^–[3]. In this context, it is of critical importance to use the same analytical procedure.

Analytical procedures are strongly dependent on in vivo and in vitro influences: In this context, the preanalytic phase is crucial for the subsequent analytic process[11] and most importantly for the interpretation of the obtained results. Point-of-care testing (POCT) has been introduced in clinical routine to provide analytical results more rapidly and to allow shorter therapeutic response intervals. For POCT systems like the ABLflex 800, preanalytic steps are decisive which include correct blood withdrawal with discarding of the first sample and immediate analysis to prevent hemodilution and stability of the specimens, respectively. Inappropriate handling and prolonged delay will result in sedimentation of RBC and will interfere with subsequent analysis. Details for preanalytics in POCT are described by Hicks et al [12]. Another important factor is the time span from blood withdrawal to their processing within the analyzer to optimize stability of hematological analysis which is time-dependent and hematology analyzer dependent[13]. In our ICU the nursing staff is trained in standardized blood withdrawal and immediate blood gas analysis within minutes after blood collection.

The samples for the ADVIA 2120 are directly sent to the hematology laboratory, marked “emergency” which guarantees immediate processing, providing results within one hour. The pre-analytic process and the rest of the testing in the laboratory is highly standardized. Thus, assuming that pre-analytic errors occurred, we would rather have to consider this a systematic error.

The ADVIA 2120 method may be influenced by hemolytic samples or lipemia leading to falsely elevated hematocrit levels, in contrast cold antibodies can decrease hematocrit. In addition, polyglobulia may affect the measurement [14]. In our population polyglobulia or lipemia was not present; cold antibodies were not searched for routinely.

The International Committee for Standardization in Hematology (ICSH) recommends the cyanmethemoglobin method as a reference method for hemoglobin measurement[7].

Although blood gas analyzers as POCT methods are increasingly used to provide rapid analysis of hematocrit in ICU, emergency departments, and operating theaters, data showing reliability between the different methods is scarce. A Belgian multicenter study compared different POCT methods to standard laboratory analyzer and found differences from 0. 6 to 4.1% [15] which was corroborated by two other studies[16, 17].

To date, we lack detailed studies addressing the impact of different analytical methods on the transfusion management. Although both tested methods showed a fair to good agreement, approximately 21% of our samples might lead to a different transfusion management. Taken together, apart from clinical parameters transfusion triggers must not only be defined as simple values but must be considered as method-dependent parameters. In the literature none of the landmark papers [1–3] mentioned the hemoglobin analyzing method. This, in turn, could in theory, lead to different results of these studies. Most importantly, multi-center trials must use the same method of analysis to avoid false transfusions.

Concerning the ICSH guidelines which recommend the cyanmethemoglobin method as a standard method, the ADVIA 2120 method might be more appropriate to measure hemoglobin/hematocrit. Nevertheless, transfusing according to the ADVIA 2120 method would increase the transfusion rate in our patients with its additional risks.

Hemoglobin Iron Determination | Northwestern Ohio Community Action Commission, Inc.

POLICY:

NOCAC Child Development will ensure all participants are screened for iron deficiency utilizing results from a Hematocrit or Hematocrit/Hemoglobin (HCT/HGB) blood test within 90 calendar days of enrollment.

REQUIREMENTS:

Early Head Start enrolled participants:

1. For a participant enrolled before the age of 12 months, the program must obtain documentation that a HCT/HGB screening was completed.
2. If there is no documentation that a screening was performed at 12 months, a screening must be performed as soon as possible.  A second HCT/HGB screening may be required to be performed for the participant at 24 months of age based on the primary care physicians risk assessments results.

Head Start enrolled participants:

1. The program is required to obtain documentation that a HCT/HGB screening was performed between the ages of 36-72 months.
2. If there is no documentation that a screening was performed after 36 months of age, a screening must be performed within 90 days of enrollment.

PROCEDURES:

1. At the initial home visit, the teacher/Home Visitor (HV) will inform parents of the program’s health requirements and determine if the participant is up-to-date on the recommended schedule.
2. NOCAC staff or Health and Safety Manager will assist the family in arranging for and obtaining HCT/HGB screening results.
   1. The parent will be asked to provide the program with the HCT/HGB screening date and results from their local WIC provider or primary care physician.
   2. If needed, the parent may sign a Release of Information form allowing the program to obtain the results from WIC or primary care physician.
   3. If NOCAC has not received a copy of the HCT/HGB screening date and results from their local WIC provider or primary care physician within approximately two weeks after sending the Release of Information, a second request will be mailed.
   4. If two weeks after mailing the second request the program has not received a response, the HCT/HGB screening will be performed by the health staff with signed parent permission.
3. When a determination has been made that the participant has not been screened for iron deficiency or the results of a previous screening cannot be obtained, NOCAC Health/Safety Manager will perform the HCT/HGB screening, the following will be adhered to:
   1. A finger stick lead screening will be performed by licensed personnel or health staff who have been trained and show proficiency in this skill.
   2. Parents will be notified when the screening will be performed.
   3. NOCAC Staff will assist parent to complete Child Lab paperwork which authorizes a finger stick.
   4. A Child Lab permission form must be completed prior to the screening being performed.
   5. Verification of parent signature on a parent agreement of services with the HCT/HGB screening marked appropriately will be done.
   6. Notification of screening results will be given to the parent as soon as possible after all screenings are completed by providing the parent with a copy of the results.
4. The following guidelines will be utilized to determine a child’s need for referral for treatment and followup.
   1. Followup on participants that fail the HCT/HGB screening will be completed by the primary care physician
   2. NOCAC Staff will assist the parent in making and keeping appointments or arranging transportation.
5. HCT/HGB screening results will be recorded in ChildPlus.
6. Participants will not be excluded from the program because of incomplete the HCT/HGB screening.
7. Pass/Fail Levels:
   1. Any hemoglobin at or above 10.1 is considered a pass.
   2. Any hemoglobin between 10.0 or below is a fail and requires an automatic referral to Health/Nutrition Services.  This referral must be completed within two weeks of the date the results were received by staff.
   3. Any hematocrit at or above 34.1% is considered a pass.
   4. Any hematocrit at 34% or below is a fail and requires an automatic referral to the Health/Nutrition Services.  This referral must be completed within two weeks of the date the results were received by staff.
8. If after 90 days from the participant’s enrollment date staff are unable to obtain a hemoglobin/hematocrit screening for any participant regardless of age, the participant must be referred to the Health Manager. Staff must include all dates they have spoken/contacted the parent regarding the missing hemoglobin/hematocrit with the referral.
9. NOCAC is the payor of last resort.

Forms and Additional Guidance:

Hemoglobin and Hematocrit Levels in the Prediction of Complicated Crohn’s Disease Behavior – A Cohort Study

Abstract

Background

Markers that predict the occurrence of a complicated disease behavior in patients with Crohn’s disease (CD) can permit a more aggressive therapeutic regimen for patients at risk. The aim of this cohort study was to test the blood levels of hemoglobin (Hgb) and hematocrit (Hct) for the prediction of complicated CD behavior and CD related surgery in an adult patient population.

Methods

Blood samples of 62 CD patients of the German Inflammatory Bowel Disease-network “Kompetenznetz CED” were tested for the levels of Hgb and Hct prior to the occurrence of complicated disease behavior or CD related surgery. The relation of these markers and clinical events was studied using Kaplan-Meier survival analysis and adjusted COX-proportional hazard regression models.

Results

The median follow-up time was 55.8 months. Of the 62 CD patients without any previous complication or surgery 34% developed a complication and/or underwent CD related surgery. Low Hgb or Hct levels were independent predictors of a shorter time to occurrence of the first complication or CD related surgery. This was true for early as well as late occurring complications. Stable low Hgb or Hct during serial follow-up measurements had a higher frequency of complications compared to patients with a stable normal Hgb or Hct, respectively.

Conclusions

Determination of Hgb or Hct in complication and surgery naïve CD patients might serve as an additional tool for the prediction of complicated disease behavior.

Citation: Rieder F, Paul G, Schnoy E, Schleder S, Wolf A, Kamm F, et al. (2014) Hemoglobin and Hematocrit Levels in the Prediction of Complicated Crohn’s Disease Behavior – A Cohort Study. PLoS ONE 9(8):
e104706.

https://doi.org/10.1371/journal.pone.0104706

Editor: John Green, University Hospital Llandough, United Kingdom

Received: January 24, 2014; Accepted: July 16, 2014; Published: August 12, 2014

Copyright: © 2014 Rieder et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: German Competency Network Inflammatory Bowel Diseases supported this work. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Introduction

Crohn’s disease (CD) is frequently characterized by the occurrence of a complicated disease behavior, defined as fistulae or stenoses, and the need for CD related surgery. Up to two thirds of the CD patients develop strictures or fistulizing complications within ten years of diagnosis [1], [2]. A large proportion of CD patients have to undergo CD related surgery at least once during their lifetime and postoperative recurrence often occurs followed by multiple surgical interventions [3]. During recent decades better control of CD associated intestinal inflammation could be achieved, due to the emergence of stronger and more selective immunosuppressive therapies and immunomodulators. Therefore clinicians desire tools to monitor for patients that have a higher susceptibility for the development of complicated disease behavior or CD related surgery as this can impact therapeutic management.

Serological markers directed against microbial peptides and linked to CD, such as anti-Saccharomyces cervisiae (ASCA) and others have been extensively investigated for disease stratification and association [4]–[6]. Limited information is available on the predictive abilities of serum markers, mainly from pediatric cohorts, indicating an increased hazard for complicated disease behavior and CD related surgery with an increasing immune response to microbial components [7]–[9]. The still limited accuracy of the above-mentioned serologic markers as well as the high costs of their determination restricts their use in clinical practice. While red cell parameters have been linked to IBD activity [10]–[12], comparably little attention has been given to hemoglobin (Hgb) or hematocrit (Hct) for disease course prediction. An exploration of these markers is warranted as one could speculate that more severe disease or tissue damage is likely to be linked to anemia.

The specific aim of this cohort study was to evaluate the levels of Hgb and Hct early in the disease course as well as during follow-up visits to an IBD center as predictive markers for complicated CD behavior and CD related surgery in a well-defined German cohort.

Materials and Methods

Patient population

We performed a cohort study among adult CD patients. The diagnosis of CD was made based on clinical, radiographic, endoscopic and histopathologic criteria [13]. All CD in- and outpatients seen at our clinic between 2000 and 2006 were asked at study entry to donate blood for our repository. Exclusion criteria for this study were A) the presence of complicated disease, defined as fistula or stricture, or intestinal surgery at the time of first sample procurement B) a follow-up of less than three years for patients with a pure inflammatory disease course and C) missing values for blood Hgb or Hct. The patients with a pure inflammatory disease course and a follow-up period of less than three years were excluded to ensure a long enough follow-up time for the development of a possible complication. The complete repository consists of 363 individual CD patients. Blood samples before complication or surgery with a minimum follow-up of three years were available in 76 patients, of which 63 had values for Hgb or Hct recorded in our database. Blood was procured at multiple time points from 34 out of the included 62 CD patients during their disease course at arbitrary visits to our IBD unit or hospital allowing a longitudinal analysis.

Full clinical data including age at diagnosis, BMI, gender, date of sample procurement, date and type of complications and surgery, disease location and disease status were obtained for the time point of first sample procurement and later updated at each arbitrary visit thereafter separately by the treating physician of the IBD unit. Once collected, data were transferred and stored in a secure coded anonymized database for analysis. Disease activity was determined by the treating IBD physician and patients were grouped in active and non-active disease, based on clinical criteria as represented in the Crohn’s disease activity index (CDAI). A CDAI point value of >150 was considered active disease and a point value ≤150 was considered inactive disease. We did not secure an exact CDAI score in our database. The disease activity evaluation was performed by four experienced IBD physicians for the majority of the patients. Iron supplementation therapy at time of initial sample procurement or during follow-up as well as number of blood transfusions during the study period were recorded. Anemia treatment was at the discretion of the IBD physician. We additionally procured information on the type of anemia present, separating the patients into iron-deficiency anemia, anemia of chronic disease, B12 or folate deficiency and renal anemia. At time of study analysis all patient charts and the database were reviewed and updated for the clinical data points. Follow-up for a particular patient was terminated if there was no further record available.

Ethics statement

Signed informed consent was obtained from all participants. The ethics committee of the University of Regensburg approved the study.

Blood analysis

All blood and sera values were measured according to standard laboratory procedures of the Department of Clinical Chemistry of the University of Regensburg. Standard laboratory values were defined as: Hgb abnormal for <13.3 g/dl for males and <11.2 g/dl for females; Hct abnormal for <40.1% for males and <34.1% for females; Albumin abnormal for <34 g/l. Anti Saccharomyces cervisiae IgG antibody was measured in the serum as previously described [6].

Phenotypical characteristics of IBD patients

The treating physician assessed the CD patients for disease phenotype at arbitrary visits during the disease course. Patient demographics at study entry (time of first sample procurement/baseline) are given in table 1. For the purpose of this study complicated disease behavior in CD patients was defined as the diagnosis of fistulae or stenoses during follow up. We did not distinguish internal penetrating from perianal fistulizing disease. Furthermore, we examined the need for CD related abdominal surgery during the follow-up period, which included abdominal surgery as well as perianal surgery.

Statistical analysis

Descriptive statistics were computed for all variables. In order to assess differences between subjects with complications or CD related surgery and those without, Student’s t-tests were used for age and BMI, Wilcoxon rank sum tests were used for disease duration, and Pearson’s chi-square test was applied for all categorical variables. A time-to-event analysis was performed to assess whether marker status was associated with occurrence of 1^st complication or surgery (defined as an event). Time-to-event analysis was performed to assess factors associated with occurrence of first complications and/or surgery (defined as an event). Time of follow-up was defined as months between time of marker determination and occurrence of 1^st event or last record of patient history if no events were observed. Kaplan-Meier plots were generated and log-rank tests were used to assess differences in event-free rates between groups. In addition, univariable and multivariable Cox proportional hazards models were used and the hazard ratios (HR) and 95% confidence intervals for each marker were estimated to assess association between low hemoglobin levels and occurrence of any event while adjusting for potential confounders (ileum involvement, active disease, disease duration, age, early disease onset, CRP and ASCA) one at a time; the same was done for low hematocrit levels. SAS version 9.2 software (The SAS Institute, Cary, NC) and R version 2.9.1 software (The R Institute for Statistical Computing, Vienna, Austria) were used for all analyses. A p<0.05 was considered statistically significant.

Results

Clinical phenotypes of the population

A total of 63 patients were included in this study. One patient developed a hematologic malignancy (non-Hodgkin lymphoma (NHL)) after end of follow-up. To ensure no subclinical influence of the NHL on the CD course this patient was excluded from the study. The median time from diagnosis to study entry (first sample procurement/baseline) was 16.5 months (25^th percentile (P25) 1.8 months; 75^th percentile (P75) 50.4 months) with 38.7% of the samples procured within 6 months and 50% within one year of diagnosis of CD. Among the patients studied a total of 34% experienced a complication or CD related surgery during a median of 55.8 months of follow-up: 11.1% progressed to complication only, 17.5% to complication and surgery combined, and 3.2% had to undergo CD related surgery only. In the patients with complications 6 perianal fistulae, 4 internal penetrating fistulae and 13 stenoses occurred. The reasons for surgery were perianal surgery in 5, abdominal surgery in 5 and both types of surgery in 4 patients. The reason for surgery in the 2 patients without a previous complication was abscess surgery without a fistula in the pathology report in the first subject and ileocecal resection without a stricture or fistula in the pathology report in the second subject. At the time of sample procurement 64.5% of the CD patients were taking immunosuppressive medication, defined as any one out of corticosteroids (including budesonide), azathioprine or methotrexate. While use of anti-tumor necrosis factor-α agents was not an exclusion criterion, no patient in this cohort received infliximab or other anti-tumor necrosis factor-α agents at time of sample procurement or during follow-up. In the CD patients with anemia based on the laboratory standard values at our University Center 44.4% has iron deficiency anemia, 22.2% anemia of chronic disease, and 11.1% each had renal disease related anemia, iron deficieny anemia and B12 deficiency combined or an unknown cause. Serum albumin measurement was not performed in 6 out of 62 patients and was normal in all other 56 patients at time of first sample procurement. 5 out of 63 patients were on iron supplementation therapy at time of initial sample procurement and an additional 14 patients received iron supplementation at any time during follow-up. One patient had a trauma during follow-up and was resuscitated with 4 units of PRBC.

As there are no established criteria for using Hgb and Hct for disease prediction in CD, we next assessed their optimal cut-off values for prediction of complicated CD behavior or CD related surgery. We the used %findcut SAS macros developed at the Mayo Clinic [14] to determine the optimal cut-off for Hgb and Hct separately for male and female study participants. Based on log-rank statistics for time-to-event analysis a cut-off value of Hgb<14.2 g/dl for males and <13.3 g/dl for females and of Hct <40% for males and <37% for females was found to be optimal. According to these cut-off values neither a low Hgb nor a low Hct were associated with age at diagnosis, age at sample procurement, disease duration, ileal involvement or the intake of immunosuppressive medication. The median time from sample procurement to the first event was shorter in patients with low Hgb (31.9 months; P25 7.8, P75 55.9 months) compared to normal Hgb (60.6 months; P25 49, P75 73.6 months; p = 0.003) and shorter in patients with low Hct compared (46.3 months; P25 13.1, P75 56.7 months) to normal Hct (62.5 months; P25 51.7, P75 78.8 months; p<0.001). A high proportion of patients with a normal Hct were on 5-ASA compared to low Hct (62.2 versus 23.5%; p = 0.004). In addition a normal Hct or Hgb were linked to a higher proportion of patients with purely inflammatory disease behavior or Vienna B1 (table 1). Considering all included samples, the levels of Hgb and Hct only weakly correlated with CRP levels (rho = −0.30 and −0.28, respectively). No association for Hgb/Hct could be detected with (1) use of corticosteroids (yes vs. no: 13.5±1.6 vs. 14.0±1.4 g/dl; p = 0.21 and 39.5±4.1 vs. 40.5±3.8%; p = 0.37, respectively), (2) use of other immunosuppressants (yes vs. no: 13.6±1.5 vs. 14.0±1.5 g/dl; p = 0.31 and 39.7±3.9 vs. 40.4±4.2%; p = 0.53, respectively), and (3) the presence of clinical disease activity at time of sample procurement (yes vs. no: 13.7±2.1 vs. 13.7±1.3 g/dl; p = 0.98 and 39.7±4.7 vs. 40.0±3.7%; p = 0.78, respectively).

The presence of low Hgb (Hazard ratio (HR) 3.4; 95% confidence interval (CI) 1.3, 8.8; p = 0.004) or low Hct (HR 3.6; 95% CI 1.5, 8.8; p = 0.013) levels at study entry (first sample procurement/baseline) predicted a faster progression to a first event, defined as fistula, stenosis or CD related surgery, in an unadjusted time to event analysis (table 2; figure 1). We then separately analyzed the occurrence of complications or CD related surgery during follow-up in the patient groups. In an unadjusted analysis a low Hgb or low Hct indicated a higher risk for early complications or CD related surgery.

Figure 1. Hemoglobin (Hgb) and hematocrit (Hct) in the prediction of complicated Crohn’s disease – Kaplan-Meier survival analysis for event-free probability.

The broken line represents the population with low Hgb (<14.2 g/dl for males and <13.3 g/dl for females) or low Hct (<40% for males and <37% for females), respectively. The full line represent the population with normal Hgb or Hct. P-values and Hazard ratios (HR) as indicated in the figure.

https://doi.org/10.1371/journal.pone.0104706.g001

To further evaluate the predictive ability of the markers we used a Cox-proportional Hazard regression model taking into consideration as potential confounders: ileal disease location, clinical disease activity, disease duration, CRP positivity and age at diagnosis. Separate models were fit correcting for one potential confounder at a time due to the restricted patient number. Low Hgb levels or low Hct levels independently indicated a faster progression to an event, defined as the occurrence of complications or CD-related surgery (table 3), which was true for all tested potential confounders with hazard ratios between 3.0 and 3.9. Of note Hgb and Hct were not time-dependent covariates. The predictive ability in our cohort was independent of the time from sample procurement to event or in other words the link between a low Hgb or low Hct with the occurrence of events was present for early as well as late events after sample procurement. This was true for all examined time points (event in <16 months from sample procurement, >16 months, >24 months, >32 months and >48 months; data not shown). We additionally evaluated a possible link between need for iron therapy and complicated CD. Neither iron therapy at time of first sample procurement (HR 2.6; 95% CI 0.75, 8.8; p = 0.13), nor iron therapy at any time during follow-up (HR 1.7; 95% CI 0.69, 4.2; p = 0.25) were associated with complications and/or need for surgery.

As Hgb and Hct levels are subject to fluctuation over time we next analyzed serial measurements in our patients over time. 34 out of 62 patients had more than one sample taken during visits to our hospital throughout the disease course (2–7 samples per individual patient, median time between samples was 7 months (25^th percentile 3.2 months, 75^th percentile 13.6 months). The subgroups of patients with multiple visits compared to patients with only one visit were comparable in respect to age at study, age at diagnosis, the occurrence of complications, CD related surgery as well as time from sample procurement to first complication and CD related surgery. There was a significantly shorter disease duration, higher proportion of patients using immunosuppressants at the time of sample procurement and steroids at any time during follow-up as well as upper GI-tract location in the multiple visits group compared to the single visit group (table S1).

59% of CD patients had no change in their Hgb levels (normal versus low) and 35% had no change in their Hct levels on multiple visits during follow-up. We then compared the CD patients with a stable low Hgb or Hct with patients with a stable normal Hgb or Hct, respectively (table 4, figure 2). Patients with a stable low Hgb or Hct had a higher frequency of complications and events (complication and/or CD-related surgery) compared to CD subjects with stable normal Hgb or Hct values. In addition CD patients with a stable low Hgb had a shorter time to complication compared to stable normal Hgb.

Figure 2. Serial measurements of hemoglobin (Hgb) during follow-up and association with complicated Crohn’s disease – Kaplan-Meier survival analysis for event-free probability.

The broken line represents the population with low Hgb (<14.2 g/dl for males and <13.3 g/dl for females) or low Hct (<40% for males and <37% for females), respectively. The full line represent the population with normal Hgb or Hct. P-value as indicated in the figure.

https://doi.org/10.1371/journal.pone.0104706.g002

Clinical predictors for disease progression in complication naïve CD patients have been described, such as ileal disease location, disease duration, age at disease onset or positivity for ASCA IgG [9], [15]. We therefore tested, if the addition of Hct or Hgb to these factors can enhance the predictive capability (table 5). The AUC (Area under Receiver Operating Characteristics curve) for disease prediction of a low Hgb or low Hct was in the range of 0.66, which was higher compared to serology or clinical factors. When combining serology and clinical factors with Hct or Hgb the AUC increased to >0.7.

Discussion

We describe the use of Hgb and Hct for the prediction of complicated disease behavior or CD related surgery (defined as an event) in patients with CD. A low Hgb or Hct determined close to diagnosis independently indicated a higher hazard for the earlier occurrence of a complicated disease event. Hgb and Hct were not time dependent covariates. Patients with a stable low Hgb or Hct during serial follow-up visits had a higher frequency of events compared to patients with a stable normal Hgb or Hct, respectively. The addition of Hgb or Hct to commonly used clinical or serologic predictors can enhance the accuracy of disease stratification.

Anemia, indicated by low Hgb or Hct values, can be a trait of chronic inflammatory disorders, and occurs frequently in patients with CD [16]–[18]. Approximately 10% to 70% of subjects with CD develop anemia during their disease course [19]. The most common underlying cause for anemia in CD is multifactorial, with the major factors being iron deficiency anemia and anemia of chronic disease or both [20]. Studies have shown that anemia can be a potentially helpful tool for diagnosis of IBD [16]. Anemia appears to be related to chronic disease activity in CD [20] and is associated with an increased need for hospitalizations [19]. In addition markers related to erythrocytes, such as the red cell distribution width, have been linked to IBD activity [10]–[12]. Our cohort is in concordance with the literature with >60% of the patients having either iron deficiency anemia or anemia of chronic disease, with a minority being related to Vitamin B12 or folate deficiency or renal anemia.

Studies of this kind are of special importance as the course of CD is highly variable with patients changing from a pure inflammatory disease pattern to complicated disease behavior potentially at any time. Identifying markers to stratify patient groups at risk for developing certain disease phenotypes can make a tailored therapy possible. Several cross sectional, as well as prospective studies have shown a link between a profound serum immune response to microbial components and the occurrence of complicated disease courses [4], [5], [7]–[9]. Limited information is available on routine blood tests such as Hgb and Hct and outside of this investigation there is no study available evaluating Hgb for this matter. Our study shows that blood tests routinely used for CD patients in a clinical setting can aid as predictors of a more severe disease course, defined as the earlier occurrence of fistulae, stenoses or CD related surgery. Importantly, this was true for early events after sample procurement as well as later events, such as those occurring more than two years after sample procurement. The addition of Hgb and Hct to clinical or serologic factors increased their predictive accuracy. Interestingly this effect was independent of disease acitivity, serum CRP, ileal involvement or disease duration. Our data therefore indicates that a low Hgb or Hct value early in the disease course could be an additional tool on top of a thorough clinical workup that can help identifying CD patients at risk for complications.

Determination of Hgb and Hct is easy and rapid to perform, cheap and well reproducible and is part of standard of care laboratories in IBD patients. The lack of specificity of anemia for CD can be neglected once diagnosis is made on clinical grounds. Hct and Hgb fluctuate over time. However, about half of the CD patients in whom multiple samples throughout the disease course were available remained either normal or low for Hgb and Hct. This could indicate that despite fluctuations certain patients have a predisposition to lower Hgb or Hct values indicating more severe disease or normal Hgb or Hct values indicating less severe disease [20]. This can be explained by anemia of chronic disease or increased blood loss due to intestinal ulcerations. Patients with multiple visits had a significantly higher rate of upper GI involvement, a higher intake of immunosuppressants, but the same amount of complications and surgeries compared to patients with only one visit. One possibility for multiple visits despite the same amount of complications is the need to monitor immunosuppressive medications or the increased rate of upper-GI involvement.

Interestingly, patients with active CD have significantly impaired intestinal iron absorption [21]. Iron absorption was negatively correlated with serum CRP and IL-6 levels in a pediatric CD population. It has been hypothesized that IL-6, released by the human intestine, induces hepcidin in human hepatocytes that in return inhibits intestinal iron absorption [21]. Interestingly, in our cohort neither CRP nor clinically active disease at time of sample procurement were linked to low Hgb or Hct levels. This could be explained by a possibly delayed effect of active disease on reduction in Hgb/Hct or by the limitations of CRP or clinical disease activity in depicting actual intestinal mucosal damage. The application of iron therapy was not linked to complications or need for surgery. The missing association could be due to the low patient number of this study in combination with the multifactorial etiology of the anemia in this population.

However, certain limitations apply: Our clinic is a regional referral center for IBD and therefore our patient population represents more severe disease courses with a relatively high amount of complicated disease behavior, CD related surgery and ileal disease location. This could introduce a referral bias. The majority of the IBD patients were evaluated by four experienced IBD physicians using pre-set criteria. We cannot exclude that few patients included in the study were evaluated by additional GI certified providers. However criteria used were identical for all included subjects. This study is a cohort study and not a controlled prospectively designed study. We are aware of the potential presence of a subclinical complication at the time of sample procurement, which might explain the early occurrence of complication or surgery after sample procurement. 50% of the samples were taken more than one year after diagnosis, which could represent a different population compared to studies using samples strictly taken at time of diagnosis only. The sample size is moderate. A larger cohort would enable a more detailed analysis in respect to type of complications, such as separating perianal fistulizing and internal penetrating disease courses or separating the type of anemia. None of the patients had fecal calprotectin measured at time of serum sample procurement or during the disease course. We did not have the exact duration of treatment that was administered during the follow-up period and therefore did not perform a more detailed analysis of the impact of therapies on Hgb and Hct levels. Nevertheless, we believe that our data support the concept of a predictive ability of the blood tests Hgb and Hct for complicated CD behavior and CD related surgery.

Conclusion

Decreased levels of Hgb or Hct could serve as additional indicators for a more rapid progression towards a complicated CD behavior or CD related surgery. This study needs to be independently validated in a larger prospective study.

Acknowledgments

We would like to thank the study nurses and physicians of the Department of Internal Medicine I for their contribution to this work.

Author Contributions

Conceived and designed the experiments: FR GP ES SS AW F. Kamm AD US FO RL JPA GR F. Klebl. Performed the experiments: FR GP ES SS AW F. Kamm AD. Analyzed the data: FR GP ES SS AW F. Kamm RL F. Klebl. Contributed reagents/materials/analysis tools: FR GP ES SS AW F. Kamm AD US FO RL JPA GR F. Klebl. Wrote the paper: FR GP ES SS AW F. Kamm AD US FO RL JPA GR F. Klebl.

References

1. 1.
   Louis E, Collard A, Oger AF, Degroote E, Aboul Nasr El Yafi FA, et al. (2001) Behaviour of Crohn’s disease according to the Vienna classification: changing pattern over the course of the disease. Gut 49: 777–782.
2. 2.
   Rieder F, Brenmoehl J, Leeb S, Scholmerich J, Rogler G (2007) Wound healing and fibrosis in intestinal disease. Gut 56: 130–139.
3. 3.
   Jess T, Riis L, Vind I, Winther KV, Borg S, et al. (2007) Changes in clinical characteristics, course, and prognosis of inflammatory bowel disease during the last 5 decades: a population-based study from Copenhagen, Denmark. Inflamm Bowel Dis 13: 481–489.
4. 4.
   Landers CJ, Cohavy O, Misra R, Yang H, Lin YC, et al. (2002) Selected loss of tolerance evidenced by Crohn’s disease-associated immune responses to auto- and microbial antigens. Gastroenterology 123: 689–699.
5. 5.
   Dotan I, Fishman S, Dgani Y, Schwartz M, Karban A, et al. (2006) Antibodies against laminaribioside and chitobioside are novel serologic markers in Crohn’s disease. Gastroenterology 131: 366–378.
6. 6.
   Rieder F, Schleder S, Wolf A, Dirmeier A, Strauch U, et al. (2010) Association of the novel serologic anti-glycan antibodies anti-laminarin and anti-chitin with complicated Crohn’s disease behavior. Inflamm Bowel Dis 16: 263–274.
7. 7.
   Dubinsky MC, Kugathasan S, Mei L, Picornell Y, Nebel J, et al. (2008) Increased Immune Reactivity Predicts Aggressive Complicating Crohn’s Disease in Children. Clin Gastroenterol Hepatol 10: 1105–1111.
8. 8.
   Amre DK, Lu SE, Costea F, Seidman EG (2006) Utility of serological markers in predicting the early occurrence of complications and surgery in pediatric Crohn’s disease patients. Am J Gastroenterol 101: 645–652.
9. 9.
   Rieder F, Schleder S, Wolf A, Dirmeier A, Strauch U, et al. (2010) Serum anti-glycan antibodies predict complicated Crohn’s disease behavior: a cohort study. Inflamm Bowel Dis 16: 1367–1375.
10. 10.
    Song CS, Park DI, Yoon MY, Seok HS, Park JH, et al. (2012) Association between red cell distribution width and disease activity in patients with inflammatory bowel disease. Dig Dis Sci 57: 1033–1038.
11. 11.
    Yesil A, Senates E, Bayoglu IV, Erdem ED, Demirtunc R, et al. (2011) Red cell distribution width: a novel marker of activity in inflammatory bowel disease. Gut Liver 5: 460–467.
12. 12.
    Cakal B, Akoz AG, Ustundag Y, Yalinkilic M, Ulker A, et al. (2009) Red cell distribution width for assessment of activity of inflammatory bowel disease. Dig Dis Sci 54: 842–847.
13. 13.
    Van Assche G, Dignass A, Panes J, Beaugerie L, Karagiannis J, et al. (2010) The second European evidence-based Consensus on the diagnosis and management of Crohn’s disease: Definitions and diagnosis. J Crohns Colitis 4: 7–27.
14. 14.
    Mandrekar JN, Mandrekar SJ, Cha SS (2003) Cutpoint Determination Methods in Survival Analysis using SAS. Proceedings of the 28th SAS Users Group International Conference (SUGI) Paper 261.
15. 15.
    Beaugerie L, Seksik P, Nion-Larmurier I, Gendre JP, Cosnes J (2006) Predictors of Crohn’s disease. Gastroenterology 130: 650–656.
16. 16.
    Cabrera-Abreu JC, Davies P, Matek Z, Murphy MS (2004) Performance of blood tests in diagnosis of inflammatory bowel disease in a specialist clinic. Arch Dis Child 89: 69–71.
17. 17.
    Cash JM, Sears DA (1989) The anemia of chronic disease: spectrum of associated diseases in a series of unselected hospitalized patients. Am J Med 87: 638–644.
18. 18.
    Vijverman A, Piront P, Belaiche J, Louis E (2006) Evolution of the prevalence and characteristics of anemia in inflammatory bowel diseases between 1993 and 2003. Acta Gastroenterol Belg 69: 1–4.
19. 19.
    Wilson A, Reyes E, Ofman J (2004) Prevalence and outcomes of anemia in inflammatory bowel disease: a systematic review of the literature. Am J Med 116 Suppl 7A: 44S–49S.
20. 20.
    Kulnigg S, Gasche C (2006) Systematic review: managing anaemia in Crohn’s disease. Aliment Pharmacol Ther 24: 1507–1523.
21. 21.
    Semrin G, Fishman DS, Bousvaros A, Zholudev A, Saunders AC, et al. (2006) Impaired intestinal iron absorption in Crohn’s disease correlates with disease activity and markers of inflammation. Inflamm Bowel Dis 12: 1101–1106.

90,000 What is hematocrit?

Hematocrit, or HCT, refers to the number of red blood cells in the entire blood volume. Measured as a percentage. It is sometimes also referred to as packed cell volume. The hematocrit is measured using a blood test. Abnormal levels can be a symptom of a variety of medical diseases or conditions.

An HCT test is often ordered as part of a complete blood count. This can be repeated several times to determine if certain conditions, such as anemia, are improving.The test involves obtaining blood from a vein. The vein, often in the arm or arm, is cleaned with an antiseptic. A needle is then inserted into the vein and blood is drawn.

Although blood tests are considered routine and rarely cause complications, problems are possible. Infection can develop, especially if the site has not been cleared long before the blood is drawn. Other rare complications that can occur include excessive bleeding and local hematoma.

After taking the blood, it is analyzed using special laboratory equipment to determine the hematocrit.Laboratory equipment varies and different methods can be used for measurement. Dense blood containing red blood cells is separated from the liquid blood component after centrifugation. This helps determine the percentage of the total blood volume that contains red blood cells.

Normal levels will differ depending on the sex and age of the patient. For example, in newborns, the normal range is 55 to 68 percent. By age 10, 36 to 41 percent is considered normal.Normal values ​​for adult males are 42 to 54 percent, and for adult females, the normal range is 38 to 46 percent.

A low hematocrit level can indicate a variety of conditions, such as excessive blood loss or nutritional deficiencies. Bone marrow disorders such as leukemia can also cause a decrease in the number of red blood cells and lead to a decrease in hematocrit.

Various conditions can also cause increased hematocrit.Certain lung diseases, such as chronic obstructive pulmonary disease, can cause an increase in the red blood cell ratio. Dehydration and high altitude can also often lead to an increase in hematocrit.

Another reason for HCT testing may be for blood doping testing in athletes. When an athlete uses steroids, medications can increase the percentage of red blood cells in the body and raise the hematocrit above normal levels. Professional athletes often take a baseline HCT to determine their HCT percentage.This level is compared to random tests conducted to test for blood doping

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90,000 “Hematocrit is below normal — what does this mean in an adult?” – Yandex.Qu

In this article, we consider what to do if the hematocrit is below normal, what does this mean in an adult?

Determination of the hematocrit value is included in the extended general blood test. The criterion allows you to assess the work of the hematopoietic system.The functioning of other organs directly depends on its full-fledged functional activity, since it is erythrocytes that deliver oxygen to organs and tissues.

A decrease in the hematocrit value can proceed without manifestation of pronounced clinical symptoms. A person can attribute increased fatigue to high workload and lack of time for rest. However, a decrease in hematocrit is one of the first symptoms of anemia that requires treatment. The article also discusses the danger of a prolonged decrease in hematocrit.

Contents

What does hematocrit show?

The value reflects the volume of the liquid part of the blood, which contains the formed elements (erythrocytes, leukocytes, platelets) in the bloodstream. The hematocrit is measured as a percentage. So, if the analysis indicates that the hematocrit is 40%, this means that 100 ml of blood contains 40% of erythrocytes, platelets, etc.

Decreased blood hematocrit is observed in patients with a low number of red blood cells in the bloodstream.The indicator also takes into account the size of the blood cells. Their decrease is naturally reflected in the results of the analysis.

Measurement of hematocrit is advisable in the diagnosis of anemia and hyperproteinemia, as well as in assessing the effectiveness of the selected treatment methods. A study is done on dehydrated patients to assess the severity of their condition. It is included in the list of mandatory determined indicators for people who are planned to have a blood transfusion and for pregnant women.

Main article: What is hematocrit, why is it needed and what are its norms?

Below normal hematocrit – what does it mean?

A low hematocrit in an adult indicates a decrease in the number of red blood cells in the blood. In this case, the doctor will prescribe additional laboratory tests and methods of instrumental diagnostics. Among the laboratory parameters, it is important to determine: the level of iron and ferritin, as well as to assess the biochemical parameters of the blood.Of the instrumental methods, it is preferable to conduct an ultrasound examination of the digestive organs, liver and small pelvis. Based on the results of a comprehensive examination and the patient’s anamnesis, the doctor determines the cause of the lowered hematocrit.

It should be borne in mind that if a woman took a biomaterial for analysis during menstruation, then the hematocrit below normal is a standard phenomenon. During this period, a woman loses a certain amount of blood, which means that the level of red blood cells is somewhat reduced.

It is important to follow the rules of patient preparation, as well as taking and transporting biomaterial. During venipuncture, destruction of red blood cells in the test tube (hemolysis) can occur. For example, due to strong or prolonged squeezing of the site of taking the biomaterial with a tourniquet or at improper storage temperature of the collected blood. The readings obtained cannot be considered reliable, and the patient will definitely need to take the biomaterial again.

Reasons for a decrease in hematocrit in adults

Only the attending physician after a complete diagnosis can establish the exact cause in each specific case.Consider the main causes of low hematocrit in adults.

Anemia (anemia) describes a group of similar syndromes, combined on the basis of a total decrease in hemoglobin level and the number of red blood cells. It should be noted that the isolated term “anemia”, without clarifying explanations, does not describe a specific disease. In this case, it is only a separate symptom of a disease.

A decrease in the number of erythrocytes is mainly accompanied by changes in their qualitative composition.This leads to a deterioration in respiratory activity and the gradual development of oxygen starvation of tissues of all organs. The main symptoms of anemia are:

• pale skin;
• increased weakness and fatigue;
• desire to eat chalk, earth, raw meat;
• hair loss, brittle nails, dry skin;

90,061 decreased memory and performance;

• bluish or yellowish tint to the sclera;
• earthy skin tone and;
• Constant sleepiness;
• frequent headaches and dizziness;

90,061 shortness of breath even with little physical activity;

• tachycardia.

The main causes of anemia

There are many mechanisms for the development of anemia. Let’s consider the main ones:

• Disruptions in the synthesis of red blood cells and hemoglobin due to a lack of iron, vitamins B 9 and 12 in the human body, as well as for pathologies of the red bone marrow.
• Red blood cell deficiency in the presence of large blood loss, for example, with serious injuries or during surgery. A similar condition occurs in people with chronic bleeding (hemorrhoidal bleeding, inter-cycle blood loss in women, etc.)etc.). The main mechanism is a decrease in iron concentration, not a decrease in the number of red blood cells.
• The mechanism of enhanced destruction of blood cells. The average lifespan of red blood cells is 4 months. With the manifestation of pathologies affecting the hematopoietic system, blood cells begin to degrade at an increased rate. The decay process is also influenced by external factors, for example, the use of large quantities of vinegar.

The prognosis of the outcome of iron deficiency anemia is extremely favorable.The condition is stopped by taking iron and vitamins. The outcome of other forms of anemia depends on their severity.

Fluid in the body

The hematocrit is also lowered with an increased fluid content in the body of an adult. This condition is not associated with excessive fluid intake, but with its retention in the body. Causes: kidney pathology, viral or bacterial infection. An increase in blood plasma volumes occurs, while the number of erythrocytes does not increase.This naturally leads to a decrease in the hematocrit value.

Hyperproteinemia and nutrition

Another reason is hyperproteinemia. Pathology is characterized by an excess content of proteins in the bloodstream. It occurs due to a violation of the normal functioning of the liver. Proteins begin to “attract” excess water, while the number of red blood cells does not increase. Thus, their percentage with blood plasma decreases.

In adult patients, the hematocrit is also reduced with a sharp change in diet, prolonged fasting and blood loss.

Pregnancy

During pregnancy, especially in the second trimester, a decrease in the value under consideration is considered normal. In women, the level of plasma volume rises, and red blood cells are not synthesized at an increased rate. Thus, the percentage of plasma-erythrocytes shifts towards a decrease in the latter. The decrease in the hematocrit value begins from the fourth week, the peak reaches 31-35 weeks.

However, a long-term decrease in the indicator should not be ignored; additional diagnostics should be carried out in order to exclude the possible development of pathological conditions.So, a decrease in hematocrit up to 30% can cause the development of intrauterine fetal hypoxia, impaired placental blood circulation, delayed fetal development, etc. The indicator from 15 to 25% indicates the need for immediate hospitalization of a pregnant woman, followed by continuous monitoring.

Other reasons

Also, a low hematocrit in adults can be observed at:

• lead intoxication;

90,061 splenomegaly;

• leukemia;

90,061 conditions after chemotherapy;

• acute infectious processes;
• severe intoxication.

Is low hematocrit dangerous?

The main function of red blood cells is an adequate supply of cells and tissues with molecular oxygen. When they decrease, there is an insufficient supply of oxygen to the organs. This is especially negatively reflected in the functional activity of the brain. A person has a decrease in concentration, memory and mental activity.

Adults with low hematocrit are more susceptible to infectious diseases, unable to work properly, get tired faster and lose concentration.In the future, a shortage of red blood cells can lead to the development of pathologies of the cardiovascular system, liver and kidneys.

Methods for increasing hematocrit

You should not try to increase the level of red blood cells in your blood on your own. The necessary treatment will be selected by a specialist based on the results of laboratory and instrumental studies. In case of prolonged fasting or dehydration, it is necessary to restore a normal diet and the amount of fluid consumed per day.In this case, the patient can do without drug therapy. It is also important to establish a daily routine and plan enough time for rest and walks in the fresh air.

In case of a shortage of iron or other elements, the doctor will select the necessary drugs, their dosage and determine the duration of the course of taking them. You should not independently interrupt the course of treatment, even if the symptoms of anemia no longer bother you. The diet should include foods rich in iron. For example, beef liver, seafood, lentils, red meat, nuts, and pomegranate.

The use of alternative methods of treatment without prior agreement with a doctor is unacceptable. It should be emphasized that these methods cannot be a sufficient alternative to the methods of official medicine. They can only complement the treatment, provided that the selected components do not block the action of the medicinal components.

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90,000 causes of low, high levels – Health – Home

A blood test for hematocrit shows the percentage of individual blood elements (erythrocytes, leukocytes and platelets) to its liquid part (plasma).With the help of this indicator, the degree of anemia is often determined, since with this disease the hematocrit level can decrease to 15-20%.

It is believed that the average hematocrit for men is between 0.4 and 0.48. And for women, the norm is in the range of 0.36-0.46. However, the hematocrit value directly depends on the person’s age. The younger the patient, the lower the level. In a young child, the hematocrit is typically 20 percent higher than that of an adult.This indicator is considered to be the norm.

Sometimes an increase or decrease in the hematocrit level indicates the presence of a disease. In particular, with a prolonged lack of air (hypoxia), the body tries to increase the efficiency of blood oxygen transfer from the lungs to all organs. This is done by increasing hemoglobin and increasing the number of red blood cells. Accordingly, there is an increase in the level of hematocrit. This effect is present in people with respiratory problems, in tourists who often visit the mountains, in those who live in these areas, as well as in smokers.

The hematocrit can also be elevated with dehydration (dehydration). What happens with infectious diseases of the digestive system, with severe burns and with a long stay in a dry hot climate. Another reason for an increase in hematocrit is kidney cancer. In this case, an increase in blood density is observed. However, a more accurate diagnosis can be made only after additional examinations.

Those who are in hot climates for a long time tend to get a lot of sun exposure.About whether it is useful or harmful to sunbathe, see the plot from the program “No forbidden topics”:

A decreased hematocrit can also indicate the presence of various diseases. A low test result count is considered an underlying symptom of hypoplastic anemia. Also, the level of hematocrit is low with an excessive presence of fluid in the blood, otherwise called overhydration. The reasons may be: poisoning, infectious or viral disease, renal failure.

Also, a decreased hematocrit may be a sign of hyperproteinemia. This is a decrease in blood density. This can be the case with serious liver disease.

If, according to the results of the analysis, the hematocrit has an increased or decreased level, this only means that additional tests and examinations are needed. There is no point in panicking, because often the hematocrit is successfully leveled out with proper nutrition, which includes all the vitamins the body needs, as well as with refusal from alcohol and cigarettes.

Glossary

0 – 9

Preliminary differentiation (division) of leukocytes into three subpopulations. The main advantages of automatic cell differentiation are speed and high accuracy: compared to counting 100 cells with manual microscopy, the automatic analyzer counts 15,000 cells on average in one sample.

Sysmex separates lymphocytes, neutrophils and a mixed cell population of monocytes, basophils and eosinophils. Analysis using other technologies separates leukocytes into lymphocytes, monocytes and a mixed population of granulocytes. Isolation of a separate fraction of neutrophils gives an advantage in the diagnostic value of the result, since neutrophils are an early marker of inflammation and infectious diseases, rather than monocytes.

Complete differentiation of leukocytes into five main subpopulations, which are normally contained in peripheral blood at certain concentrations, is the division of cells into lymphocytes, monocytes, eosinophils, basophils and neutrophils.The ability of 5-diff analyzers to perform separate counts of small cell types (monocytes, eosinophils and basophils) is a significant advantage.

The results are provided as a percentage of the total number of leukocytes and in absolute value, since it is more informative: in various diseases, the ratio of cell subpopulations is disturbed, which is why the use of the percentage of cells without absolute values ​​is impractical.

The fundamental difference from 3-diff analysis technologies is that the identification of each cell is carried out on the basis of three-dimensional analysis, and not only the cell size.This allows the identification of immature and abnormal cells, which helps in determining the possible causes of the patient’s illness.

The latest modern hematology analyzers are able to separately classify immature granulocytes (IG) as the sixth subpopulation and provide values ​​as a percentage of total leukocytes and in absolute numbers.

The term “6-diff analysis” refers to the classic 5-diff analysis with an additional count of immature granulocytes (IG) as the sixth leukocyte subset.The Sysmex XN and XN-L series analyzers count immature granulocytes as diagnostic parameters as a percentage of the total leukocyte count and as an absolute value as part of a standard assay.

A

Sysmex analyzers use a special principle for counting blood cells: the cells are counted according to the number of pulses generated in a certain volume of blood.The advantage of this approach is that there is no need to perform calibration while using the analyzer.

Sysmex method for evaluating the signals of individual cells during the measurement process and determining their belonging to certain population clusters. Since the method provides a high flexibility, taking into account the biological variation between patients, it allows for more accurate differentiation results, especially for pathological samples in which the cell morphology may be altered due to disease.

Albumin is a low molecular weight soluble protein that is synthesized in the liver and found in the blood. In terms of quantity, albumin prevails in the blood in comparison with other proteins and performs binding and transport functions. If the kidneys work properly, they preserve all the most important elements in the blood, including albumin. In healthy people, only a small amount of protein is excreted daily.In contrast, albuminuria is a pathological condition of the body in which a large amount of protein is detected in the urine over a long period of time (> 30 mg / 24 h). This allows early recognition of nephropathy. Early diagnosis of (micro-) albuminuria can prevent or slow down the process of severe kidney damage.

Anemia is generally defined as a decrease in hemoglobin (HGB) levels below the minimum range of normal values.The values ​​that determine the presence or absence of anemia depend on the sex and age of the patient. Hematocrit (HCT) is a concomitant indicator as it also decreases with anemia. Anemia is a symptom rather than a disease in its own right, with many reasons that need to be identified for successful treatment.

B

Some bacteria may be present in the urine of healthy patients.Large numbers of bacteria are caused by poor hygiene or urinary tract infections. Bacteria can be classified into gram-positive and gram-negative in terms of cell wall composition. Depending on the type of cell wall, they are sensitive to different antibiotics.

Basophils belong to the group of granulocytes and are the least common type of leukocytes in the peripheral blood.Despite their similarity to eosinophils, an increase in the concentration of basophils does not always indicate an allergy or the presence of a parasitic infection. Together with mast cells, they act as effector cells in complex processes such as chemotaxis or nonspecific cell adhesion, and act as immune modulators during allergic reactions.

Most proteins normally remain in the blood because they are too large to pass through the glomerular membrane.However, if these filters are damaged, proteinuria, the presence of protein in the urine, can develop. Protein in urine is a common symptom of kidney disease, but not very specific. A temporary increase in the amount of protein in the urine is possible with exercise, fever, or stress.

Bilirubin is formed during the breakdown of hemoglobin, which is released mainly during the destruction of old erythrocytes in the reticuloendothelial system.It then binds to albumin and is carried in the blood to the liver.

Pathological processes that increase the concentration of conjugated bilirubin in plasma, such as fibrosis and swelling or necrosis of liver cells, also lead to an increase in the content of bilirubin in the urine.

A type of body fluid sample, typically in the veterinary field.

C

An optional software application built into the Extended IPU that is activated when interference is detected in the analysis of red blood cells or related parameters (eg MCHC). These can be cases of cold agglutination, hemolysis or hypoosmolarity, and others.The CBC-O algorithm provides reliable information about the causes of interference, suggests replacing erroneous values ​​of the affected parameters with the results of their counterparts from the RET channel, and automatically recalculates erythrocyte indices. This feature relieves the laboratory from the need for additional processing of a number of problematic samples, contributing to more automation of the workflow.

A technology (method) used to differentiate stained cells in a blood smear or on a cytocentrifuge slide by capturing images and recognizing them using artificial neural network technology.High-resolution images of cells are displayed on the screen for validation (confirmation) or subsequent reclassification, and can also be further transmitted online, including for consultation with other experts.

Urinary casts usually consist of Tamm-Horsfall protein (mucoprotein) (BTX). Approximately 50 mg of liquid BTX is excreted daily, so detection of BTX in urine is normal.

Hyaline casts (Hy. CAST) are the most common type of casts in urine. They are cylindrical in shape and appear almost transparent. The cylinders are formed as a result of the coagulation of mucoprotein in the lumen of the renal tubules. The presence of hyaline casts in the urine may be due to dehydration, fever, or intense exercise.

Pathological casts (Path. CAST) contain inclusions. They are formed if particles such as erythrocytes or renal epithelial cells are present during BTX coagulation.The particles adhere to the fibrillar protein network and remain trapped in it. Such cylinders appear in urine if pathological processes take place in the kidneys. Examples: granular cylinders, cell cylinders, waxy cylinders.

D

Parameters containing diagnostically significant information about the patient, which is transmitted to clinicians and hospital departments.

Scatter plots (chart type) are generated by placing two different fixed signals for each cell opposite each other in a 2D analysis. Signals can be derived from volumetric impedance, high frequency electromagnetic energy, optical (direct scattered light and side scattered light signals) and cytochemical indication (side fluorescent light).
More than one cell population can be evaluated and displayed. These two or more separate cell populations are differentiated using the ACAS method (not used in all devices and channels), which is superior in quality (for differential leukocyte counts) to fixed synchronization.
More than two captured signals per cell can be recorded, so more than one scatterplot can be generated to isolate and display different cell populations.A software component for monitoring the entire XN analysis system: this is an application that protects the operating environment, as well as monitors maintenance and performance issues.

Abbreviation for digital morphology, vol.e. digital morphology; also refers to the CellaVision AB DM Series analyzers.

Automatic re-measurement of a sample to obtain reliable analysis results, based on a set of rules, with a profile identical to the original order (measurement).

Yeast cells are smooth, colorless and usually ovoid.Their walls are birefringent, cells are of different sizes and often bud. The most common type of yeast found in urine is Candida albicans . Yeast cells in the urine may be due to contamination from the skin or vagina, or it may indicate a fungal infection of the urinary tract.

E

Basophils belong to the group of granulocytes and are the least common type of leukocytes in the peripheral blood.Despite their similarity to eosinophils, an increase in the concentration of basophils does not always indicate an allergy or the presence of a parasitic infection. Together with mast cells, they act as effector cells in such complex processes as chemotaxis or nonspecific cell adhesion, and act as immune modulators during allergic reactions. Eosinophils belong to the group of granulocytes, as they are filled with granules containing various enzymes. They can move and phagocytose (i.e.that is, absorb) particles. Since they kill parasites by secreting certain cytotoxic enzymes and are involved in allergic reactions, the increased concentration of eosinophils, in all likelihood, may be associated with parasitic invasion or allergy. Eosinophilia can also indicate the development of malignant diseases, as in some types of neoplasia.

“Epithelium” is a general term for the cellular tissue that covers certain surfaces.Different types of epithelial cells are present in the urinary tract: squamous (SEC) and non-planar (Non SEC) epithelium. Non-squamous epithelial cells are also subdivided into transitional epithelial cells (Tran. EC) and renal epithelial cells (RTEC).

Squamous epithelial cells are large, flat cells of irregular shape. They contain a small central nucleus and a large volume of cytoplasm. The edges are often curled up and the cage can be rolled up to form a cylinder. The presence of squamous epithelium in the urine is normal.These cells get there from the lower part of the urethra or from the skin that comes in contact with urine during collection. Thus, their presence may be due to contamination typical of improper collection of urine samples mid-void.

The cells of the transitional epithelium (urothelium) vary in size and shape depending on their origin. They can be sourced from the upper part of the urethra, ureters, or the renal hilum (scar). A small amount of transitional epithelium in the urine is normal.

Renal tubular epithelial cells are slightly larger than leukocytes and contain a large, round nucleus. They can appear flat, cubic, or columnar. They enter the urine from the nephron tubule system. The presence of renal tubular epithelium in the urine indicates kidney problems.

Erythrocytes deliver oxygen to the tissues of the body, moving through the circulatory system.These are round smooth red cells. If red blood cells are unchanged in shape, they are called isomorphic or eumorphic, and they do not come from the glomeruli. If red blood cells have been damaged, they are called dysmorphic. Deformation (damage) occurs when passing through the glomerular structures of the kidneys, however, in addition, its appearance is possible with prolonged contact with urine. Abnormal dysmorphic red blood cells are also called “acanthocytes”. Their presence may indicate a glomerular disorder such as glomerulonephritis.

The appearance of an insignificant amount of red blood cells in the urine can be considered normal. However, a large number of red blood cells can indicate damage, the presence of crystals, stones, or a urinary tract infection.

A set of haematological inflammation parameters that quantify and characterize particular lymphocytes (RE-LYMP, AS-LYMP) and the activation status of neutrophils (NEUT-GI, NEUT-RI).These diagnostic parameters provide additional information about the activation of the patients’ immune response and help clinicians monitor inflammatory conditions in more detail. They become available with license activation on XN systems via XN-DIFF measurement. The use of WPC is of extra value here as it excludes malignancies reliably.

Software utility for standardization and control of workflow, as well as synchronization of processing of samples, orders and data streams (for example, extended technical validation based on a system of predetermined rules).In the XN Series analyzers, the extended information processing system – the Extended IPU – allows you to perform a wide range of standard and optional functions at all stages of the analysis: “before”, “during” and “after”. In addition, the software solution’s “workspace management” capabilities include a set of customizable rules to ensure standardization of technical and biomedical validation, as well as tools to optimize workflow.

F

Sysmex technology used in X and XN hematology analyzers for differential cell counting to detect and differentiate blood cells from all three major cell lines after intravital labeling with proprietary fluorescent labels and laser irradiation in a flow cell.

A chemical compound that can bond with other structures and exhibit the phenomenon of fluorescence: after excitation with light of a certain wavelength, a molecule emits light with a slightly longer wavelength. The electrons inside the molecule absorb the energy of the exciting light (for example, laser radiation), rise to a higher energy level, and return to their original level within a short period of time.At this point, they emit most of the excess energy in the form of light. Less energy is released as thermal energy, so the wavelength of the emitted light is longer (at less energy) than the wavelength of the exciting light. Which wavelengths are suitable for excitation and which are emitted depends on the properties of the fluorochrome.

Fluorochromes are used to label individual cell components (eg nucleic acids) because the fluorescent light emitted can be measured.A photomultiplier tube is usually used as a detector. This means that fluorochromes can serve as markers for these cell components, allowing their quantitative and qualitative analysis, since the fluorescence intensity is proportional to the amount of an individual component, for example, intracellular RNA and / or DNA.

Thanks to the use of an original reagent system, the Sysmex XN and XN-L hematology analyzers allow differentiating cells by their functionality, especially in cases where it is difficult to make a decision based on morphology.Determination of cell functionality is based on the analysis of the individual lipid composition of cell membranes and allows differentiation of mature and immature cells, as well as reactive and malignant cells.

Unique Sysmex reagents allow making a conclusion about:

1.cell maturity,

2. cell malignancy,

3. state of cell activation.

G

Hemoglobin is an iron-containing red blood pigment that is found in red blood cells and provides oxygen transport in the body.The detection of hemoglobin in urine may be due to its increased content, or the presence of red blood cells in the sample. Elevated values ​​of this indicator are an important symptom in trauma, the presence of crystals, glomerulonephritis, kidney stones, or urinary tract infections.

Sysmex technology used in hematology and urine analyzers to optimize cell / particle counting.The sustained flow separates cells or particles from each other and aligns themselves in a straight line before entering the flow cell, preventing them from passing through the aperture together and recirculating after the initial readout.

In particular, red blood cells change their shape under the influence of rapid acceleration in suspension. When using hydrodynamic focusing, the level of acceleration is significantly reduced, due to which the native characteristics of the cells are preserved to a greater extent.

Histograms are of the type of diagrams and are built on the basis of measuring the size (volume) of each individual cell, which is determined by the height of the pulse generated when the cell passes through the impedance aperture. Also, histograms can be built on the basis of other signals generated by the recorded cells, for example, the signal of forward light scattering, lateral light scattering or fluorescence, which reflect such properties of the cell as the cross-sectional area (size), the complexity of the intracellular structure and the content of nucleic acids, respectively.

It is possible to evaluate and display more than one cell population, for example, on erythrocyte and platelet histograms, as well as a curve with three peaks of distribution of leukocytes in 3-diff analyzers. These two or more separate populations of cells are distinguished by so-called “discriminators”, expressed in a certain cell size.

The urine of a healthy person contains only traces of sugar, i.e.e. glucose. Glucose appears in urine when its concentration in the blood increases as a result of glucose metabolism disorders. Determination of glucose in urine has a high diagnostic value for the early detection of disorders such as diabetes mellitus.

Granulocytes belong to the group of myeloid leukocytes, which are characterized by the presence of granules in the cytoplasm.They are divided into neutrophils, eosinophils, and basophils. Granulocytes constitute a group of polymorphonuclear leukocytes, in contrast to mononuclear leukocytes (lymphocytes and monocytes).

In the biological fluid analysis mode on the Sysmex XN and XN-L series analyzers, as well as in some X-class analyzers, the number of granulocytes is displayed by the PMN parameter. When combined with the MN parameter, which indicates the number of mononuclear cells, the test results can help determine the cause of an existing infection or inflammation, for example, in CSF (cerebrospinal fluid) samples.

H

A long-term monitoring parameter used to control diabetics’ medical status. It has become a frequently ordered test in medical labs nowadays because of the increase in lifestyle diseases such as diabetes. Automated HbA _1c testing is facilitated with the Tosoh HLC-723 G11 Analyzer, which can also be integrated into XN-9000/9100 configurations ‘Sorting & Archiving’ or ‘Maximum Workload’ including the tube-sorting process.

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Using the Aged Sample Identifier (software application that must be activated if required) on the XN and XN-L Series analyzers reliably differentiates samples with abnormal distribution on the WDF scatterogram into truly abnormal samples and old or improperly stored samples.This application is effective in detecting false positive flagging, especially the “Blasts / Abnormal lymphocytes?” (Blasts / Abn Lympho?), Which results in fewer smears performed for this type of specimen. This reduces the effort to process samples that have changed due to the influence of time or external factors such as temperature, so that the main focus of attention will be focused on truly pathological samples that require more careful analysis.Sysmex recommends the use of the Old Sample ID in laboratories where the workflow is complicated by the high proportion of old samples.

Flow cytometry using monoclonal antibodies by differentiating the surface characteristics of cells. This term has a broader meaning than “immunophenotyping” and can be used to describe, for example, the reference platelet counting method (using antibodies to CD41 / 61), with which platelet counting in the PLT-F channel on Sysmex XN analyzers demonstrates excellent correlation of results.

Flow cytometry using monoclonal antibodies by differentiating the surface characteristics of cells. This term is commonly used to refer to the precise differentiation of leukocytes in the differential diagnosis of leukocyte abnormalities such as leukemia and lymphoma. If this term is used in relation to platelet counting, then it implies an extended analysis, including the study of the status of cell activation, etc.d.

The impedance (direct current) method is based on the possibility of using an electric field created between two oppositely charged electrodes to count and determine the size of cells. Blood cells do not conduct electricity well. The diluent (reagent), in which the cells are suspended in a diluted state during counting, is an isotonic solution that is a good conductor.Thus, as cells in the diluent pass through the aperture (narrow opening) between the electrodes, each individual cell momentarily increases the impedance (resistance) of the electrical circuit between the electrodes. The electrical impulse generated by each cell is proportional to the size (volume) of the given cell.

Dedicated measurement channel in the XE-2100 and XE-5000 analyzers for the detection of immature myeloid cells.Analysis in this channel improves flagging for immature myeloid cells, such as blast cells, which are considered abnormal in peripheral blood.

Sysmex laboratory analysis solutions are intelligently managed through an embedded software concept. This makes it possible to harmonize and standardize the relationship between the sample itself and the data flow, regardless of the type of system, whether it is a single analytical module or several work areas connected into a single network located in different places.
However, Sysmex offers more than just software to take your laboratory analysis to the next level. These are Sysmex Academy Training services, distance learning and offsite educational seminars, as well as consulting services and assistance.

Software utility (including the required hardware) through which the Sysmex analyzers are started and controlled.In the XN-Series, the IPU has a number of standard functions for different stages of the analysis. In particular, they can be linked to the capabilities of the Extended IPU to extend the functionality of the system.

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Ketones in urine indicate an increased breakdown of fat in the body.This may be due to insufficient energy intake in the form of carbohydrates. When fatty acids are broken down in the liver, intermediates are formed called “ketone bodies” (acetoacetic acid, β-hydroxybutyric acid and acetone). The presence of ketones in urine is possible with increased breakdown of fat, which is especially important when studying metabolic decompensation in diabetes mellitus.

Sysmex Automatic Hematology Analyzer Group, including the XE, XT and XS Series.The X-Class analyzers use fluorescence flow cytometry technology to analyze blood samples by separating leukocytes into 5 subpopulations and provide the laboratory with a variety of advanced parameters that enhance diagnostic capabilities.

Implies increasing the value of parameters or their combinations for diagnostics and therapy / monitoring – only on the basis of verified data.

Glomerular filtration is the first stage of urine production. Through this process, the kidneys filter excess fluid and metabolic waste products from the blood to remove them from the body.

The renal corpuscles filter about 1 liter of blood per minute due to the pressure gradient on the capillary walls.The filtrate formed in the glomerular capsule, containing water, glucose, amino acids, uric acid, urea, electrolytes, etc., is known as “glomerular filtrate” or “primary urine”.

Modular and scalable software system, which consists of various embedded components (information processing unit (IPU), extended software system Extended IPU, remote / web components) and has a single user interface.The system includes functions for workflow control, validation based on a set of predetermined rules, system maintenance and networking of individual analyzers or complex solutions, both analyzing in different laboratory directions, and located in different places. The system integrates equipment or work areas in the fields of hematology, hemostasis and urinalysis.

Creatinine is a breakdown product of creatine phosphate in muscle, and its amount depends on muscle mass.Normally, creatinine is formed at a fairly constant rate (about 1 g of creatinine is excreted per day). Thus, creatinine concentration can be used to interpret the results of urine samples taken during vaginal voiding in order to account for differences in urine concentration and obtain more consistent results.

Crystals in urine can take many different forms.They are formed by the precipitation of substances dissolved in the urine, such as inorganic salts or organic compounds. Crystals are usually not clinically significant unless the patient has metabolic disorders, stones (urolithiasis), or the drug needs to be adjusted. The most significant crystals in this context are cystine, tyrosine, leucine and cholesterol.

Sysmex method for measuring hematocrit (HCT).Hematocrit is a measure of the ratio of the total (cumulative) volume of red blood cells to the total volume of whole blood. Expressed as an index in SI (l / l) or as a percentage (%) value.

In Sysmex analyzers, the hematocrit value is determined using the impedance of the accumulation of RBC volume based on the pulse height of each individual cell. Thus, the hematocrit value is measured directly, rather than calculated, as is the case with analysis using other technologies.

L

Leukocyte esterase is an enzyme produced by leukocytes, or rather granulocytes. Detection of leukocyte esterase activity indicates the presence of granulocytic leukocytes. An increase in this indicator is an important symptom of inflammatory diseases of the urinary tract and kidneys.

Leukocytes are a vital part of the immune system. They help protect the body from infections and foreign organisms. As a rule, leukocytes are round in shape and, being a granulocyte type, also have granularity. Their diameter is approximately 1.5-2 times the diameter of erythrocytes. The most common type of white blood cell in urine is neutrophils (i.e.e., neutrophilic granulocytes), while lymphocytes or eosinophils (eosinophilic granulocytes) are rare in urine. In healthy people, few white blood cells may be present in the urine, but high levels may indicate inflammation or infection of the urinary tract.

Lymphocytes originate from the lymphoid lineage (as opposed to the myeloid lineage).Lymphoid cell development is not restricted to the bone marrow and takes place in primary and secondary lymphoid organs.

Lymphocytes defend the organism against infection by distinguishing the body’s own cells from foreign ones. Molecules recognized by the body as foreign are known as antigens. Each lymphocyte is only stimulated by one specific antigen. When lymphocytes recognize this antigen, they produce chemicals to fight it.

There are three main types of lymphocytes: B lymphocytes, T lymphocytes and natural killer (NK) cells.Lymphocytes belong to the mononuclear white blood cells. Although compared to other white blood cells all lymphocytes are small and round without granules, there is a large variety of different subtypes, and distinguishing between them morphologically is tricky.

Reasons for an increased lymphocyte count include infection or inflammation, as well as certain types of malignancies, especially haematological malignancies. Despite giving an absolute and relative lymphocyte count, several flags on Sysmex analyzers can point to suspicious lymphocytes for which, if present, a follow-up test should be performed.

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A function that allows for the on-line analysis of individual samples.

The scalability of the XN concept allows for system upgrades to adapt the solution to the needs of the laboratory.This concept includes the ability to select performance indicators, clinical indicators and professional services.

Brand name for methanol-free staining reagents manufactured by RAL Diagnostics and used in the RAL Stainer and RAL semi-automatic blood smear staining device.

The average content of hemoglobin in a red blood cell is calculated based on the values ​​of the total red blood cell count (RBC) and hemoglobin (HGB). MCH [pg] = HGB / RBC. The normal range of MCH values ​​depends on age. The MCH value is usually proportional to the mean erythrocyte volume (MCV), since cell size is largely determined by the hemoglobin content.

Cells that have normal MCH levels are called normochromic, while cells with low and high values ​​are hypochromic and hyperchromic, respectively. A low MCH level indicates that the cells contain too little hemoglobin due to insufficient production. These cells are called hypochromic because they appear pale when examined under a microscope.

The average concentration of hemoglobin in an erythrocyte is calculated based on the hematocrit (HCT) and hemoglobin (HGB) values ​​and reflects the quantitative ratio of the hemoglobin content in the erythrocyte to the cell volume.MCHC [g / dl] = HGB / HCT. The normal range of MCHC values ​​is extremely stable throughout life and generally has a very narrow range with minimal coefficient of variation.

MCHC is also used to determine normo-, hypo- and hyperchromic erythrocyte populations. Cells with a low hemoglobin content are lighter in color and have a low MCHC level. An increase in the MCHC level for any clinical reason is extremely rare, practically only in the case of a change in the shape of the cells to spherical (due to loss of the membrane) or if the cells are largely dehydrated.Hyperchromic red blood cells have an unusually high concentration of hemoglobin due to loss of cell volume.

The

MCHC is typically used to monitor the analyzer’s correct operation.

Average cell volume is calculated based on the total red blood cell count (RBC) and hematocrit (HCT). MCV [fl] = HCT / RBC. The normal range of MCV values ​​depends on age.The terms “normocytic”, “microcytic” and “macrocytic” are used to describe populations of red blood cells with normal, low and high MCV values.

Since the size of red blood cells depends on the hemoglobin content, the inability to produce hemoglobin leads to a decrease in red blood cells – microcytosis. Macrocytic cells are found when the division of red blood cell precursor cells in the bone marrow is impaired.

The urethra (urethra) originates from the base of the bladder and drains urine from the body.It is the only structure of the urinary system, the structure of which differs significantly between men and women, due to the dual role of the male urethra, which serves to transport both urine and semen.

The ureter is the tube that carries urine from the kidney to the bladder. There are two ureters, one for each kidney.

The bladder is a hollow muscular organ that collects and stores urine coming from the kidneys through the ureters before it is excreted (urinating). It is a very stretchable (elastic) organ. Typically, the adult bladder stores 300 to 500 ml of urine before the urge to urinate occurs, but it can hold much more.

Monocytes, like lymphocytes, belong to the group of mononuclear cells, but their formation occurs in the myeloid lineage, the cells of which are produced in the bone marrow.

Monocytes play a key role in the immune response. They can quickly move to the areas of infection and differentiate into macrophages and dendritic cells, causing an immune response.The cells of the monocyte-macrophage system can absorb foreign particles and break them down into antigens, which they can then present on their surface.

Carrying out automatic counting of monocytes is possible both as the ratio of the number of monocytes to the total number of leukocytes, and in the form of their absolute content in the sample. An increased concentration of monocytes can be a sign of various diseases, for example, chronic inflammation or infection, but it can also occur in malignant diseases such as chronic myelomonocytic leukemia.

N

Nephron is a microscopic structural and functional filtering unit of the kidney. Each kidney is made up of over one million nephrons that purify the blood and balance the circulatory components.The nephron consists of the renal corpuscle, a complex system of renal tubules and an associated capillary network.

Nephrons process the blood flowing through the bringing arterioles by glomerular filtration, tubular reabsorption and secretion. In different parts of the nephron, many processes take place before the filtrate (primary urine) turns into a final product called “urine”.

Neutrophils belong to the group of granulocytes.They play an important role in immune defense and are the first immune cells to arrive at the site of infection – usually within an hour. This is due to a process called chemotaxis. Neutrophils can phagocytose other cells, such as bacteria, which are recognized as harmful to the body. However, in this process, the neutrophils themselves do not survive. The pus is made up mostly of dead neutrophils and processed bacteria. The absolute and relative count of neutrophils provides certain information for the diagnosis and monitoring of the development of infectious diseases, and is also taken into account when conducting chemotherapy.An increased concentration of neutrophils can also be observed in non-pathological conditions, for example, after suffering stress or in smokers.

Fluorescence flow cytometry detects immature cells based on their higher nucleic acid content compared to mature cells.Consequently, immature granulocytes (IG) are included in differential leukocyte counts as a separate subpopulation. Immature granulocyte counts include promyelocytes, myelocytes, and metamyelocytes, but not stab granulocytes.

The presence of immature granulocytes is always a pathology, with the exception of the period immediately after childbirth and in newborns less than 3 days old. The accuracy of automatic counting of immature granulocytes is significantly higher than with manual microscopy, which is ideal for continuous monitoring of patients’ condition and allows you to replace more time-consuming manual cell counting with a standardized method.

Nitrite is formed as a result of nitrate reduction. Various bacteria that cause urinary tract infections (UTIs) produce enzymes that convert nitrates to nitrites. The presence of nitrites in urine indirectly confirms a bacterial infection (bacteriuria). Common microorganisms that can cause urinary tract infections, such as Escherichia coli and Enterobacter, Citrobacter, Klebsiella and Proteus, form enzymes that reduce nitrate in urine to nitrite.

A negative nitrite test strip does not rule out urinary tract infection, as there are bacteria that do not produce nitrite. Thus, nitrite is a specific but not sensitive indicator of UTI. In addition, with vigorous bacterial growth, nitrite may eventually be degraded to nitrogen, causing the residual amount of nitrite in the sample to fall below the detection limit.

Normocytic anemia may result from decreased production of red blood cells, increased destruction of red blood cells, or blood loss.In normocytic anemia, the value of the total content of red blood cells is low, but the size of the cells and the content of hemoglobin in them remain normal.

O

Special articles on clinical and diagnostic topics with a scientific and educational bias.Articles are devoted, for example, to topics such as coagulation, hematology, urinalysis and body fluids, etc.

The classic 8-parameter hematological analysis includes the counting of erythrocytes, leukocytes and platelets, as well as the determination of the hemoglobin level (HGB), hematocrit number (HCT), the average erythrocyte volume (MCV), the average hemoglobin content in the erythrocyte (MCH) and the average hemoglobin concentration in erythrocyte (MCHC).

The TWO application improves and simplifies the entire platelet analysis workflow by optimizing the use of repeat (reflex) tests in the PLT-F channel and intelligent software support in the differential diagnosis and monitoring of thrombocytopenic patients.

The new TWO algorithm is built into the Extended IPU and can be used in conjunction with the PLT-F application.

The

MWO application embedded in the Extended IPU is a special solution for differentiating reactive and malignant monocytosis. The MWO concept helps to reduce unnecessary blood smear microscopy while optimizing the mechanism for detecting CML, thereby improving laboratory workflow.

Parameters containing personalized diagnostic information that is shared with physicians and hospital departments or relevant physicians outside the laboratory / hospital.

Analyzers, which use the relative principle of cell counting, determine the number of blood cells based on the number of pulses generated in a fixed period of time.These systems are prone to aperture clogging errors that require regular calibrations to resolve.

P

Parameters that, in addition to and in combination with diagnostic / recorded parameters, contain diagnostically relevant information for exclusive use in the laboratory for the purpose of validating results and reporting diagnostic data.These results are not directly communicated to, for example, hospital departments or doctors, but diagnostic results can be communicated based on diagnostic / logged parameters.

Parameters which, in addition to and in conjunction with basic parameters, provide diagnostically relevant information for exclusive use in the laboratory for the purpose of confirming results and reporting diagnostic data.These parameter results are not transmitted directly to, for example, hospital departments or doctors, however, diagnostic results in relation to basic diagnostic parameters can be transmitted in this way.

Pathological changes in leukocytes can occur from the myeloid or lymphoid lineage. They can be caused by both reactive and non-reactive diseases (neoplasm or malignant tumor).Reactive changes can be observed with the development of infectious or inflammatory diseases, while malignant changes indicate the development of leukemia, lymphoma and other malignant hematological neoplasms. To differentiate between the various diseases associated with white blood cells, it is critical to determine their exact number, type and degree of maturity. Automated hematology analysis is a very important component of the diagnostic process and helps to determine the presence of disease, as it provides accurate cell counts and reveals prominent cell populations.In diseases associated with white blood cells, making the correct diagnosis is a difficult task and requires studying all the information obtained from the results of general and differential blood tests, morphology, immune phenotyping and other analyzes.

Primary urine is a fraction of blood plasma filtered by renal corpuscles.Due to the abundant blood supply to the kidneys and a large number of filtering units – glomeruli, the body produces about 150 liters of primary urine daily. Approximately 99% of the primary urine is reabsorbed through the epithelium of the glomeruli, so only 1.8 liters should be excreted from the body every day. The components of the primary urine correspond to the composition of the blood plasma without protein.

pH is an indicator that characterizes the degree of acidity or alkalinity of a medium based on the concentration of hydrogen ions.Persistently acidic or alkaline urine may indicate an acid-base imbalance. Permanently alkaline urine pH values ​​indicate a urinary tract infection. With microscopy, it is important to take into account that at a pH above 7, cells can lyse faster than under normal (from slightly acidic to almost neutral) conditions.

Clinical Parameters are optionally available for XN Series Platelet Analyzers due to special fluorescent markings and are highly accurate in the thrombocytopenic range.Demonstrates very good correlation with the reference method (CD41 / 61).
Platelet fluorescence also allows the determination of the immature platelet fraction (IPF), which reflects the thrombopoietic activity of the bone marrow, which is especially useful in detecting thrombocytopenia and its possible causes.

The renal corpuscle is the site of filtration of blood plasma.It consists of a glomerulus and a capsule of the renal glomerulus, or “Bowman’s capsule”. The supplying arterioles form a network of high-pressure capillaries called the “glomerulus”. The glomerular capillary bundle filters the blood based on particle size and the filtrate collects in the surrounding bowl-shaped chamber, Bowman’s capsule (glomerulus capsule).

The renal tubule is a long convoluted structure arising from the glomerulus and functionally subdivided into three main parts: the proximal convoluted tubule, the loop of Henle (with descending and ascending knees), and the distal convoluted tubule.After passing through the renal tubule, the filtrate enters the collecting duct system.

The kidneys are the two bean-shaped organs of the renal system. They perform a number of important functions, including regulating the balance of water and electrolytes, and filtering and removing metabolic waste (such as urea, uric acid and ammonia), drugs, and toxic substances.In addition, the kidneys secrete hormones that promote the formation of red blood cells (erythropoietin, EPO), regulate blood pressure (renin) and strengthen bones (absorption of calcium by converting calcidiol to calcitriol).

A test parameter indicating the presence of lymphocytes with high fluorescence, which are activated cells (secretion of antibodies of B-lymphocytes / plasma cells), if systemic hematological diseases are excluded.CBC parameters such as mean erythrocyte volume (MCV), mean erythrocyte hemoglobin (MCH), and mean erythrocyte hemoglobin concentration (MCHC) are collectively referred to as erythrocyte counts. In combination with the red blood cell volume distribution (RDW), these indicators are used to narrow down the number of possible causes of anemia in a patient.The mean erythrocyte hemoglobin concentration (MCHC) is an early sensitive marker because the mean erythrocyte hemoglobin (MCH) and mean erythrocyte hemoglobin concentration (MCHC) fall before the red blood cells become microcytic.

A group of compounds that are used (in addition to being widely used in industry) as fluorochrome markers for supravital staining of cells using a semiconductor laser as a light source in Sysmex equipment for blood and urine analysis (patented by Sysmex).

These compounds have several advantages: their maximum absorption can be precisely adapted to the laser wavelength, their permeability to cells and nuclei can be individually adjusted, and their sensitivity (affinity) to certain cell components, for example, nucleic acids, can be created if necessary, through changes in the molecular structure. Polymethines have excellent signal-to-noise ratios, are readily degraded in aqueous waste and are considered mutagenically safe compared to other nucleic acid-binding fluorochromes.

The Sysmex X-Class and XN Series analyzers (including the XN-L) use several different polymethine reagents to allow differential analysis of mature and immature cells in all three cell lines.

A type of laser, also called a “diode laser”, which is used in the latest generation of Sysmex flow cytometers for the analysis of blood and urine.Unlike previous gas lasers, these lasers consume less power (usually in the red part of the spectrum), take less time to wake up (allow the system to start up quickly), and have a longer life.

Characteristic of convergence (closeness to each other) of the results: repeated serial studies under identical conditions.

Automatic re-measurement of the sample to obtain reliable analysis results in the event that certain errors occurred in the analyzer during the first measurement (related, for example, to pressure, temperature, etc.).

Optimization and harmonization of all integrated laboratory processes with an emphasis on total cost, while considering their contribution to ensuring fast and high quality results.

The UX and UF series urine analyzers use Sysmex technology, thanks to which the determination and differentiation of urine particles and cells is carried out by means of their supravital staining using special fluorescent markers and subsequent exposure to laser light when passing through a flow cell.

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When an object passes through a beam of light, the light changes direction.This phenomenon is called light scattering and occurs at all angles between 0 and 360 degrees. The direction of the scattered light gives information about the size and quality of the object.
Forward scattered light (light scattered at a low angle) allows you to determine the size of an object. In addition to size, forward scattered light is influenced by the shape of the object and the refractive index. The detection of this light signal is usually done with a fast photodiode.
Side scatter light (light diffused at a wide angle) provides information about the intrinsic quality of an object.In cells, the side scattered light is affected by the presence or absence of granules. This light signal requires a sensitive photomultiplier tube as a detector, since its intensity – in comparison with the light scattered in the forward direction – is several times weaker.

The immature platelet fraction (IPF) is determined by PLT-F analysis.Immature platelets are analogous to reticulocytes and reflect the thrombopoietic activity of the bone marrow. Determination of the fraction of immature platelets is carried out both in relative and in absolute terms, and is especially useful for tracking the dynamics of thrombocytopenia and determining its possible causes.

An automatically calculated parameter that provides information on the level of variability of red blood cells (RBC) by volume.RDW is a quantitative measure of the variability in the size of individual red blood cells. Displayed as standard deviation (RDW-SD) and coefficient of variation (RDW-CV).

A high RDW value indicates an abnormal inhomogeneity in the size of individual erythrocytes (anisocytosis), which is well observed with microscopy of a blood smear. RDW is used to differentiate anemias with other identical erythrocyte indices.

Reexamining a sample based on a predefined rule system with a different or extended analysis profile for more reliable results.

The value obtained from the RET scatterogram to determine the RET-H parameter _e , which reflects the level of hemoglobin saturation of the reticulocyte population.

The RET application, optionally available on the XN and XN-L series analyzers, has high clinical value and is used to count and differentiate reticulocytes according to their stages of maturity (high fluorescence reticulocytes (HFR), medium fluorescence reticulocytes (MFR), low reticulocytes fluorescence (LFR)) due to special fluorescent staining.Additionally, the analysis in the RET channel allows you to obtain the results of an optical platelet count (PLT-O).

RET analysis also allows to determine the fraction of immature reticulocytes (IRF = HFR + MFR) and the equivalent of hemoglobin in reticulocyte (RET-H _e ), which allow to judge the quantity (erythropoietic activity) and quality (synthesis and content of hemoglobin) again formed erythrocytes. This is important in the differential diagnosis of anemia. In addition, RET-H _e is an early indicator of changes in the saturation of erythrocytes with hemoglobin, which is useful, for example, in monitoring the effectiveness of therapy.

The XT-4000i and XT-2000i Analyzers and the XE-Series Analyzers use the term “RET” to refer to the reticulocyte channel that provides data on the above parameters, included partly in the standard configuration and partly as an option.

The reticulocyte production index (RPI) reflects the erythropoietic activity of the bone marrow in patients with anemia.This index, in contrast to a simple reticulocyte count, is used to assess the adequacy of the bone marrow response in anemic patients. In the absence of anemia, the index has no practical value.

RPI is determined by the following formula: RPI = (RET% × HCT) ÷ (0.45 × maturation period of red blood cells in the blood (in days)). 0.45 is the ideal hematocrit value where the RPI is identical to the percentage of reticulocytes, ideally around 1% for a healthy person. In anemic patients with adequate bone marrow response, the RPI is> 2.0.At the same time, the opposite statement (if RPI <2.0, then the bone marrow response is considered inadequate) is not always true.

A qualitative marker of a proper bone marrow response to anemia is an increase in absolute reticulocyte count along with a clear increase in immature reticulocyte fraction (IRF).

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A design solution from Sysmex that makes working with equipment more pleasant: the developers put user convenience first and optimized the interaction between the operator and the system that he uses on a daily basis.

The SILENT DESIGN ^® solution was developed with five pillars to continuously improve the user experience with the device: Human – Space – Appearance – Seriality – Durability. All five principles are taken into account in the manufacture of our products based on SILENT DESIGN ^® to create an extremely positive experience.

Flag system messages are the result of a complex analysis system (complete differentiation), which allows for the qualitative identification of immature and abnormal cells.
The flag system helps reduce laboratory uptime and cost-effectiveness by significantly reducing manual differential counting and directing the test sample for further pathology analysis through generated flags. In the future, manual microscopic analysis plays an important role in fixing any remarkable elements of the morphological structure and confirming the presence of abnormal populations of cells, which during the automatic analysis were identified as suspicious and flagged to attract the operator’s attention.
Flags are also used in pre-parsers. Here, they generally indicate excessively low or high counts and unreliable results, for example due to interference.

“Glomerular filtration rate” (GFR) is the volume of fluid filtered by the capillaries of the renal glomeruli into Bowman’s capsule per minute.In healthy adults, the GFR is approximately 125 ml / min (i.e., approximately 150 liters of primary urine are produced per day) and is an important indicator of kidney function.

A common traditional test that serves as a sensitive but not specific marker of inflammation. It can be used in the diagnosis and monitoring and control of various autoimmune diseases, acute and chronic infections, and neoplastic diseases.ESR is also used as a marker of “general physical condition”, which is assessed in conjunction with the patient’s medical history and physical examination.

The cyanide-free sodium lauryl sulfate hemoglobin measurement method used in the Sysmex analyzers provides reliable results by efficiently lyzing red blood cells, leukocytes and lipids, thereby reducing potential interferences.

Sysmex XTRA Online is a special section of the Sysmex library on the official website containing many articles about both the company’s products and other related topics. This section is based on the Sysmex XTRA printed edition, produced by Sysmex in some countries, including Russia.

X

Unique WPC measurement option for hematopoietic progenitor cell counting (HSC, HPC).XN Stem Cells shows a high correlation with CD34 counts by flow cytometry in mobilized peripheral blood samples.

Optionally available on the XN and XN-L Series analyzers, the XN-BF application is of high clinical relevance and is used for automatic and standardized analysis of body fluids.The application allows analysis without pretreatment of samples at any time with excellent reproducibility of results, which reduces the number of time-consuming manual counting in the counting chamber.

In addition to the quantitative analysis of leukocytes and erythrocytes, a general count of nucleated cells is carried out, and leukocytes are divided into mononuclear cells and polymorphonuclear cells, which guarantees rapid recognition of infectious diseases and other disorders.

A functional application included as standard with the XN Series analyzers and of high clinical value in the field of CBC.

An additional benefit over standard CBC is achieved by counting normoblasts (nucleated red blood cells, NRBC) as a separate population. This can be important for identifying critical disorders in intensive care patients, and is also necessary for accurate counting of the number of leukocytes in the presence of normoblasts, for example, in newborns, when their concentration is high enough. Thanks to the automatic counting of normoblasts, the need for manual counting is eliminated, the time of the result is accelerated and the workflow is standardized.

A functional application included in the standard configuration of the XN Series analyzers and of high clinical value in the area of ​​differential leukocyte counting in whole blood samples.

An additional advantage over the standard division of leukocytes into 5 subpopulations is achieved by counting immature granulocytes (IG) as a separate population, a three-dimensional flag system with high sensitivity and special messages that provide the doctor with additional diagnostic information.