Hct blood test low meaning. Hematocrit and Hemoglobin: Understanding HCT Blood Tests
What does a low hematocrit blood test mean? How is hematocrit measured and what can it indicate about your health? Get answers to these questions and more.
Understanding Hematocrit (HCT) Blood Tests
Blood is composed of red blood cells (RBCs), white blood cells (WBCs), and platelets suspended in a liquid called plasma. A hematocrit (HCT) lab test measures the percentage of blood that is made up of red blood cells. This test is often included as part of a complete blood count (CBC) and can provide important insights into your overall health.
Purpose and Importance of HCT Testing
The primary purpose of an HCT test is to evaluate the concentration of RBCs in your blood. This measurement indicates the viscosity, or thickness, of your blood and depends on the size and number of your RBCs. HCT is an important indicator of your body’s ability to transport oxygen and remove carbon dioxide.
HCT testing is commonly ordered during routine medical check-ups or to investigate certain symptoms and health conditions, such as:
- Fatigue, moodiness, or difficulty concentrating
- Heavy menstrual flow or poor nutrition
- Blood in stools or vomit
- Cancer, cancer treatment, or conditions affecting the bone marrow
- Chronic health issues like kidney disease
How is HCT Measured?
HCT is measured as a percentage, representing the proportion of your blood that is composed of RBCs. A normal HCT range is typically between 38% and 50% for women and 42% to 52% for men.
HCT levels can be affected by changes in the number of RBCs or other blood components, such as plasma or WBCs. Even if your RBC count is normal, relative increases or decreases in other blood constituents can lead to abnormal HCT results.
Getting an HCT Test
An HCT test is typically ordered by a doctor and requires a sample of your blood, which is obtained through a standard blood draw or venipuncture procedure. The test is not usually performed at home, as it requires specialized equipment and trained laboratory personnel.
The cost of an HCT test can vary depending on factors like whether it’s part of a larger panel of tests and whether you have health insurance coverage. It’s generally a routine and commonly covered test.
Interpreting HCT Test Results
What does a low hematocrit blood test mean? A lower-than-normal HCT level, known as anemia, can indicate a deficiency in red blood cells or hemoglobin. This may be caused by factors like blood loss, nutritional deficiencies, or underlying health conditions.
In contrast, a higher-than-normal HCT, or polycythemia, can result from dehydration, certain lung or heart diseases, or conditions that cause the body to produce too many RBCs.
Your healthcare provider will interpret your HCT test results in the context of your overall health and any other relevant factors. They can then determine the appropriate next steps for diagnosis, treatment, or monitoring of any underlying conditions.
Frequently Asked Questions
What are the possible causes of a low hematocrit?
A low hematocrit, or anemia, can be caused by factors such as blood loss, nutritional deficiencies (like iron, folate, or vitamin B12), chronic diseases, cancer, or conditions affecting the bone marrow.
How does a high hematocrit affect the body?
A high hematocrit, or polycythemia, can increase the thickness and viscosity of the blood, making it more difficult for the heart to pump and increasing the risk of blood clots, stroke, and other cardiovascular problems.
Can an HCT test be done at home?
No, HCT testing is not typically performed at home. It requires specialized equipment and trained laboratory personnel to collect and analyze the blood sample.
How often should I get an HCT test?
HCT is often included as part of a routine complete blood count (CBC), which is typically ordered during annual check-ups or as recommended by your healthcare provider based on your individual health needs and risk factors.
What steps are involved in getting an HCT test?
An HCT test requires a blood draw, also known as a venipuncture. A healthcare professional will clean the area, insert a needle into a vein, and collect a sample of your blood in a test tube or vial.
Are there any side effects or risks associated with an HCT test?
Beyond temporary discomfort or bruising at the blood draw site, there are usually no significant side effects or risks associated with an HCT test. The blood draw procedure itself is a common and low-risk medical procedure.
Conclusion
The hematocrit (HCT) blood test is a crucial component of a complete blood count that provides valuable insights into your overall health. By measuring the percentage of red blood cells in your blood, this test can help identify a range of conditions, from anemia to polycythemia. Understanding the purpose, process, and interpretation of HCT testing can empower you to work closely with your healthcare provider to ensure your blood health is optimized.
Hematrocit Blood Test – Testing.com
Test Quick Guide
Blood is made up of red blood cells (RBC), white blood cells (WBC), and platelets which are suspended in a liquid called plasma. A hematocrit (HCT) lab test determines the percentage of the blood that is composed of RBC.
An HCT test helps your medical provider screen for, diagnose, and monitor conditions that affect your blood or bone marrow. A measurement of HCT is routinely included in a complete blood count (CBC) but may also be ordered on its own if your provider suspects a condition affecting your RBC.
About the Test
Purpose of the test
The purpose of an HCT test is to evaluate the percentage of blood that is made up of RBC. This measurement indicates the viscosity, or thickness, of the blood and depends on the size and number of RBCs in a blood sample. HCT is most often evaluated as part of a CBC, which also includes measurements of RBC, WBC, platelets, and hemoglobin.
Often ordered during a routine medical check-up, a CBC is a common lab test. A CBC that includes HCT may also be ordered to evaluate the cause of certain symptoms, monitor patients receiving medical treatments, and track those with chronic health issues that affect the blood.
What does the test measure?
HCT measures the proportion of the blood that is composed of RBC and is expressed as a percentage.
RBCs are critical for the distribution of oxygen to the body’s cells. Once oxygen is used by cells to produce energy, RBCs transport the waste product, carbon dioxide, from the cells back to the lungs.
HCT levels can be affected by an increase or decrease in the number of RBCs and by changes in other components of the blood. Because HCT measures the percentage of RBC in the blood, relative increases or decreases in other blood components, like plasma or WBC, can lead to abnormal HCT results even if the RBC count is normal.
When should I get this test?
Your provider may test HCT as part of a CBC or if you are experiencing symptoms of an RBC disorder such as anemia. Indications for testing HCT include:
- Fatigue
- Moodiness
- Headaches
- Brain fog or difficulty concentrating
- Heavy menstrual flow
- Poor nutrition
- Blood in your stools or vomit
- Cancer and cancer treatment
- Excessive diarrhea or vomit
- Leukemia or other conditions associated with bone marrow
- Chronic health conditions, including kidney diseases
Finding an HCT Test
How can I get an HCT test?
An HCT test requires a sample of blood and is typically ordered by a doctor. A blood draw, also called venipuncture, is conducted by a health provider or a laboratory technician in a medical setting.
Can I take the test at home?
HCT testing is not usually performed at home. Conducting this test requires specialized tools and trained laboratory personnel.
How much does the test cost?
The cost of an HCT test depends on several factors, including other tests performed at the same time and whether or not you have health insurance or are paying out-of-pocket. The cost of HCT testing is often covered by insurance due to the routine nature of the test.
Refer to your health care provider, medical facility, or insurance company for specific details on costs, copays, and deductibles.
Taking an HCT Test
A blood sample is needed for HCT testing. To collect a blood sample, a needle is inserted into your arm and a vial, also known as a vacutainer, is placed on the provider’s end of the needle. The vial is then filled with blood that is used to test your hematocrit.
Before the test
There is no special preparation needed prior to an HCT test, unless specified by your provider.
During the test
Blood draws are a common medical procedure. Usually, blood is drawn from either the top of the hand or the vein on the inside of the elbow. To conduct a blood draw:
- An antiseptic wipe is used to cleanse the area prior to the blood draw.
- A band is placed around your arm to increase pressure in your vein, making your vein more visible and easier to access.
- A needle is placed in your vein and a test tube is attached to the needle and filled with blood.
- If you are getting other blood tests in addition to an HCT test you may have more than one vial of blood drawn.
After the test
Once the blood is drawn, the nurse or phlebotomist may ask you to hold pressure on the site of the venipuncture with a cotton swab for a few minutes. They may place a bandage on the cotton swab to maintain pressure.
After any blood draw, you will want to watch out for temporary side effects such as dizziness or lightheadedness. Your provider may want you to stay seated for a few minutes until they can determine that you are safe to get up and walk or drive.
Other than possible lightheadedness and bruising at the site where blood was drawn, there are few potential side effects from a blood draw.
HCT Test Results
Receiving test results
After the test is complete, results will be sent to your doctor for interpretation. HCT test results are most often part of the results of a CBC, which may be available to your doctor within a few minutes or up to several days.
Interpreting test results
HCT test results depend on several factors, including age and sex. The cutoff values for a normal test result, called its reference range, may also vary depending on the laboratory or methods used to conduct the test. Because of the many factors that affect HCT, it’s important to talk to a doctor for support in understanding your test result.
The reference ranges listed below describe common reference ranges for hematocrit:
Hematocrit Reference Ranges for Adults
Sex | Reference Range |
---|---|
Male | 42% to 50% |
Female | 37% to 47% |
An abnormal HCT level can indicate that your blood is either too thin or too thick compared to an average person of a similar population.
An abnormally low level of HCT indicates that your cells may not be getting enough oxygen, a condition known as anemia. Abnormally low HCT may be related to a variety of causes, including:
- Loss of blood
- Poor nutrition with low intake of iron, vitamin B6, vitamin B12 or folate
- Bone marrow disorders or cancers such as leukemia, lymphoma, multiple myeloma, or other cancers that spread to the marrow
- Destruction of RBCs
- Excessive water in the body
High HCT levels indicate conditions where there is either an overproduction of RBC or an abnormally high concentration of RBCs in your body. Some examples of causes of a high HCT include:
- Dehydration
- Lung disease
- Congenital heart disease
- Heart failure
- Certain types of kidney tumors
- Smoking
- Living at high altitudes
- Secondary polycythemia, a rare group of blood disorders caused by heritable changes to genes involved in the production of RBCs causing the body to produce too many RBCs
- Polycythemia vera, a rare blood disease in which the body produces too many RBCs
Although the results are accurate, laboratory parameters and provider reference ranges as well as personal variables may be subject to differences.
Abnormal HCT test results may or may not require additional follow-up testing. HCT is often evaluated alongside other components of a CBC to look for signs of disease or monitor health conditions.
For example, a doctor may order additional testing if you have low HCT to evaluate the cause of anemia. Testing for anemia may include a reticulocyte count, a renal panel, a liver panel, hemolysis testing, or a blood smear.
Follow-up testing is based on your symptoms, medical history, and the results of other tests. For questions about follow-up testing, speak with your doctor.
Talking with your doctor can help you understand your HCT result and any next steps. You may wish to ask the following questions:
- What does my result mean for my health?
- Is there anything I can do to change my HCT levels?
- Is there any further testing that needs to be done based on my HCT levels?
Resources
- CBC Blood Test (Complete Blood Count)
Learn More - Red Blood Cell Count (RBC) Test
Learn More - Hemoglobin Blood Test
Learn More - White Blood Cell Count (WBC Blood Test)
Learn More - Platelet Count (PLT) Blood Test
Learn More - Blood Smear
Learn More - Iron Test
Learn More - National Heart, Lung, and Blood Institute: Anemia
Learn More - National Heart, Lung and Blood Institute: Thalassemias
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Hematocrit
Medical Tests
Definition
Hematocrit is a blood test that measures how much of a person’s blood is made up of red blood cells. This measurement depends on the number of and size of the red blood cells.
Alternative Names
HCT
How the Test is Performed
A blood sample is needed.
How to Prepare for the Test
No special preparation is necessary for this test.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
Why the Test is Performed
The hematocrit is almost always done as part of a complete blood count (CBC).
Your health care provider may recommend this test if you have signs of or are at risk for anemia. These include having:
- Grumpiness or tiredness
- Headaches
- Problems concentrating
- Poor nutrition
- Heavy menstrual periods
- Blood in your stools, or vomit (if you throw up)
- Treatment for cancer
- Leukemia or other problems in the bone marrow
- Chronic medical problems, such as kidney disease or certain types of arthritis
Normal Results
Normal results vary, but in general they are:
- Male: 40.7% to 50.3%
- Female: 36.1% to 44.3%
For babies, normal results are:
- Newborn: 45% to 61%
- Infant: 32% to 42%
The examples above are common measurements for results of these tests. Normal value ranges vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
Low hematocrit may be due to:
- Anemia
- Bleeding
- Destruction of red blood cells
- Leukemia
- Malnutrition
- Too little iron, folate, vitamin B12, and vitamin B6 in the diet
- Too much water in the body
High hematocrit may be due to:
- Congenital heart disease
- Failure of the right side of the heart
- Too little water in the body (dehydration)
- Low levels of oxygen in the blood
- Scarring or thickening of the lungs
- Bone marrow disease that causes abnormal increase in red blood cells
Risks
There is little risk involved with having your blood taken.Veins and arteries vary in size from one person to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling lightheaded
- Multiple punctures to locate veins
- Hematoma (blood buildup under the skin)
- Infection (a slight risk any time the skin is broken)
References
Chernecky CC, Berger BJ. H. Hematocrit (Hct) – blood. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. St Louis, MO: Elsevier Saunders; 2013:620-621.
Maheshwari A, Carlo WA. Blood disorders. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier; 2016:chap 103.
Vajpayee N, Graham SS, Bem S. Basic examination of blood and bone marrow. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 23rd ed. St Louis, MO: Elsevier; 2017:chap 30.
Review Date: 02/18/2018
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. Copyright ©2019 A.D.A.M., Inc., as modified by University of California San Francisco. Any duplication or distribution of the information contained herein is strictly prohibited.
Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Health. Please discuss with your doctor any questions or concerns you may have.
Blood mpv
Blood functions
Blood is one of the most important components in our body. It regulates body temperature and
provides metabolic processes. Due to the contractions of the heart, the blood circulates through the body and supplies oxygen and
other necessary substances all internal organs. Also, this connective tissue cleanses and removes unnecessary
metabolic products and serves as a communication system between all organs. Blood protects the body from external
dangers and with the help of antibodies helps to fight diseases. Without movement and health of this element
the human body simply cannot exist.
Blood performs the functions of:
- thermoregulation
- transportation, nutrition and metabolism
- selection and purification
- humoral regulation
- protection
Composition of blood
Blood is a combination of plasma and blood cells. Plasma is a yellowish-white liquid
from water, proteins and other trace elements. It provides movement and mobility of blood.
Blood cells are the main active elements of blood. They are of three types: red – erythrocytes, white
– leukocytes and platelets – platelets. Each of the species ensures the health of the body, performing its own
function.
Red blood cells
They leave most of the blood cells – almost 99%. Their main function is to transport oxygen to the internal
human organs. Red blood cells look like a flat tablet with a small depression in the middle – this shape
helps to hold the red pigment – hemoglobin, which in turn helps to capture and transport
oxygen. With a lack of red blood cells or hemoglobin, people experience anemia or anemia, and as a result,
weakness, fatigue, soreness and increased risk of disease in other organs.
Leukocytes
Leukocytes are white bodies and are responsible for maintaining immunity, protecting the body and fighting
infections. There are three types of leukocytes: granulocytes, lymphocytes and monocytes. These cells perform different functions
and ensure the safety of the body in different ways, complementing each other.
Lymphocytes are mainly located in the tissues of the lymphatic system and are responsible for the recognition of foreign elements. They
are one of the main parts of the body’s immunity. Lymphocytes recognize pathogens and
purposefully give a signal to other parts of the immune system about the need to destroy harmful cells.
Granulocytes are targeted directly at fighting infectious diseases. Led by signals
lymphocytes, they attack the cells of the pathogen. Also, granulocytes, or as they are also called, phagocytes perform
regulatory function in the event of allergic reactions.
Monocytes perform the function of cleaning the body. They absorb the cells of the pathogen that did not have time to destroy
granulocytes, and also help to dissolve dead cells of the body itself.
Platelets
Platelets look like plates with an uneven surface without a clear nucleus and are responsible for the regulation of the blood itself.
These cells are constantly produced along with the blood in the bone marrow, from where they then enter the vessels and other
organs.
One of the most important functions of platelets is blood clotting and bleeding control. Thanks to
due to their composition, they are able to close damage to blood vessels in a matter of time and create conditions for
plasma clotting. Platelets protect the body from internal and external damage, blood loss, and
entry of harmful substances into open wounds, contributing to their healing and tissue regeneration.
If the blood plates are missing or damaged, there may be a risk of severe bleeding. At
excess and excessive “gluing” of platelets can form random plugs in the vessels – blood clots. This
often leads to ischemic and other diseases (for example, stroke).
Dysfunction of platelets is called thrombocytopathies. It is divided into:
- Thrombocytopenia (low cell count)
- Thrombocytosis (high count)
- Thrombasthenia (impaired function)
Blood tests
Blood is involved in all important processes in the human body. Therefore, it is the indicators of this tissue
can give the broadest understanding of the state of the body. That is why a general blood test that evaluates
indicators of all three types of blood cells, is the most popular and informative. Such a study
prescribed for symptoms of almost any disease, as well as during a general check of the body. Information about
blood health and reactions occurring in blood cells serve as the most important diagnostic and prognostic
method in the treatment of patients.
Clinical blood test examines the baseline of all types of blood cells. For state research
the latter are most often used indicators PLT, MPV, PDW, PCT. These indicators objectively evaluate the overall
the content of platelets, their size and volume.
Platelet tests
PLT score
PLT. Blood cells are very small, so their final number is measured at 109/ l (10 in Art. 9 / l). Decryption
The PLT indicator informs about the state of blood clotting.
The study is prescribed for suspected disorders of the circulatory system, bone marrow (where all
blood cells), as well as vascular damage.
Main symptoms for which the PLT test is prescribed:
- Tendency to severe bleeding
- Bruising all over the body without apparent cause
- Bleeding gums
- Absence of bleeding in severe injuries
- Tendency to form blood clots
Also, the test is often prescribed in conjunction with a complete blood count for other diseases or
scheduled surgery to check platelet counts.
The normal platelet count is:
- 150-400 109 /l for men and women
- 180-450 109 /l for children
Interpretation of results:
A severe decrease in the number of platelets may indicate severe blood loss during surgery and trauma
or about disorders associated with the functioning of the bone marrow. Also, such indicators can appear in diseases
blood, infectious or chronic diseases, malignant tumors, removal of the spleen, severe
overwork, etc.
A large number of platelets usually indicates the risk of blood clots and increased blood clotting,
and can also indicate the presence of hemophilia, lupus erythematosus, thrombosis, etc.
Index mpv l
The mrv blood tests determine the average platelet size. As already known, platelets appear in the bone
brain, from where they enter the vessels, where they continue to function for up to 10 days. Usually young platelets
are produced very large and gradually decrease, accumulating efficiency. Cells that reach
certain reduced sizes and are in the vessels are called mature.
The MPV value in the blood test is very important, as it allows you to measure the size of platelets and evaluate
cell maturity. This blood index is measured in femtoliters thanks to mrv analysis.
As a rule, when analyzing the total mpv, not only the indicators of the study itself are usually taken into account, but also the results
other blood cell performance tests. MPV analyzes are usually carried out in conjunction with the study of the previous
PLT indicator. Usually, the MPV index is of diagnostic value only when the total number of
platelets, as it allows you to assess which cells are missing (young / mature).
Complete blood count mpv decoding:
Reference values:
- 7.0-10.0 in adults
- 7.4-10.5 in children
If the mpv blood test is below normal, this indicates that the platelets are too small, therefore, most
cells are old. Such indicators usually indicate a reduced production of new platelets. Mpv goes down
most often in violation of the bone marrow.
Mpv is increased in the blood test most often during the period of active growth of platelets. This happens when the bone marrow
begins to produce a large number of platelets. When this happens, young platelets overlap
mature and change the average cell volume.
The most common causes of a normal increase in blood mpv are:
- Recent bleeding or menstruation
- Operations
- Taking medication for anemia
Pathological increases in platelets can be caused by:
- Thrombocytopenia disease
- Chronic diseases of the cardiovascular system
- Hyperthyroidism
- Removal of the spleen
- Diabetes mellitus
Blood levels of MPV are also affected by diet and micronutrient intake. For example, many products
may increase blood platelet levels.
How to increase mpv in a blood test:
- Eat dark green vegetables (spinach, greens, Brussels sprouts)
- Eat the right amount of meat (especially liver)
- Dilute food with asparagus and yeast
In addition, MPV levels can be raised with medication, but only the doctor can prescribe them.
doctor.
PDW Value
This meter measures the percentage difference in platelet size. The evaluation of this index is almost always
used in conjunction with the analysis of the previous indicator in assessing the number of mature platelets.
The study allows you to determine the condition and functionality of platelets.
Normal PWD values:
- 15-17% in an adult
- 10-17% in a child
Deciphering the values of the indicator is usually carried out in conjunction with other quantitative and qualitative indices
platelets by the attending physician.
PCT
PCT evaluates the percentage of platelet volume to total blood volume. The analysis acts as an analogue of hematocrit
(a study that determines the percentage of formed elements in the blood).
The test for the percentage of platelets to other blood cells allows you to more accurately determine which
the level of the blood system there are violations.
Normal PCT values:
- 0.1-0.4% in adults
- 0.15-0.4% in children
Meaning:
A decrease in PCT usually indicates bleeding problems or even hemophilia. Such
the condition is extremely dangerous, since with the slightest injury there is a risk of losing too much blood.
An increase in the index usually indicates the risk of thrombosis and blockage of blood vessels.
Exam preparation
Most often, these tests are ordered in the presence of characteristic symptoms on the recommendation of a doctor. cell research
blood allows you to diagnose and stop many pathologies, as well as to choose the most appropriate treatment, in
depending on individual indicators.
As a rule, PLT, MPV, PDW, PCT are studied together with the complete blood count and are correlated with the assessment
all results obtained. The analysis is carried out on the basis of biological material – venous blood. At
preparation for the study usually requires not eating at least 8 hours before the test and exclude the day before
certain medications, reduce stress, and eat and drink regularly.
Automatic blood test – normal values of erythrocyte levels – Article in Yekaterinburg
Traditional manual and modern automated methods used in hematological studies differ in results. This is due to their metrological differences. The following are the values that can be obtained from laboratory tests in various groups of patients.
Hemograms obtained from the use of hematology analyzers in adult patients.
Parameter | Women | Men RBC) | 3.8 – 5.1 t/l* | 4.3 – 5.7 t/l L* |
Hemoglobin (HGB) | 117 – 160 g/L | 131 – 173 g/L | ||
Hematocrit (HCT) | 35 – 45% | 39 – 50% | ||
MCV | 80 – 100 fl* | 80 – 100 fl* | ||
MCH | 27 – 34 pg* | 27 – 34 pg* | ||
MCHC | 32 – 36 g/dl | |||
RDW | 11.6 – 14.8% | 11.6 – 14.8% | ||
Platelets (PLT) | 150 – 400 G/L* | 150 – 400 G/L* | ||
Leukocytes (WBC)** | 3.5 – 11.0 G/L* | 4.9 – 10.5 G/L* | ||
Leukocytes (WBC)*** | 4.0 – 9.0 G/L* | 4.0 – 9.0 G/L* |
*Hereinafter
- G/L – Giga/L = 10 9 /L
- T/L – Tera/L = 10 12 /L
- fl – femtoliter
- pg – pictograms
: per. from English. / ed. WELL. Titsa. – M.: Medicine, 1986, 480 p.
*** The values were developed by the working group of experts at the VNMKC for laboratory work and approved by the USSR Ministry of Health in 1978 y. 211
Venous or capillary blood with EDTA salts is taken for research. When performing studies on hematological analyzers, the photometric method is used.
Errors in hemoglobin measurement
Inflated concentration results may be due to the following factors:
- Hyperlipidemia.
- Hyperbilirubinemia.
- Cryoglobulinemia.
- High leukocytosis.
- Excess of unstable hemoglobins.
Clinical and diagnostic value:
- Increased concentration is caused by dehydration, as well as primary or secondary erythremia.
- Decreased concentration occurs with anemia or overhydration.
Some patients whose blood hemoglobin is higher than 75 g/l can increase the hemoglobin level by 20-30 g/l by taking iron supplements for 10 days, but the iron deficiency itself is not compensated. If the patient (body weight 70 kg) also receives a blood transfusion (500 ml), an increase in hemoglobin level by 12 g/l is possible.
Erythrocytes
Normal values
Age | Women (t/l) | Men (t/l) |
Cord blood | 3. 9 – 5, 5 | 3.9 – 5.5 |
2 wk. | 3.9 – 5.9 | 3.9 – 5.9 |
1 month | 3.3 – 5.3 | 3.3 – 5.3 |
4 months | 3.5 – 5.1 | 3.5 – 5.1 |
6 months | 3.9 – 5.5 | 3.9 – 5.5 |
9 months | 4.0 – 5.3 | 4.0 – 5.3 |
1 – 2 years | 3.8 – 4.8 | 3.8 – 4.8 |
3 – 8 years | 3.7 – 4.9 | 3.7 – 4.9 |
9 – 12 years | 3.9 – 5.1 | 3.9 – 5.1 902 12 |
12 – 14 years old | 3.8 – 5.0 | 4.1 – 5.2 |
15 – 17 years old | 3.9 – 5.1 | 4.2 – 5.6 |
18 – 44 years old 9 0212 | 3.8 – 5, 1 | 4.3 – 5.7 |
45 – 64 years | 3.8 – 5.3 | 4.2 – 5.6 |
65 – 74 years old | 3. 8 – 5.2 | 3.8 – 5.8 |
Venous or capillary blood with EDTA salts is used for research.
Clinical and diagnostic value
The number of red blood cells increases with:
- Dehydration.
- Reactive erythrocytosis, which is caused by a lack of oxygen in the tissues due to congenital or acquired heart defects, with cor pulmonale, frequent stay at high altitudes, with emphysema.
- Reactive erythrocytosis caused by Cushing’s disease or syndrome, corticosteroids, renal pelvic edema, various neoplasms, erythremia, polycystic kidney disease.
The number of erythrocytes decreases with:
- Anemia;
- Hyperhydration.
- Major blood loss.
- Late pregnancy.
Hematocrit
Age | Women | Men |
Umbilical cord blood | 42 – 60% | 42 – 60% |
2 wk. | 41 – 65% | 41 – 65% |
1 month | 33 – 55% | 33 – 55% |
2 months | 28 – 42% | 28 – 42% |
4 months | 32 – 44% | 32 – 44% |
6 months | 31 – 41% | 31 – 41% |
9 months | 32 – 40% | 32 – 40% |
1 year | 33 – 41% | 33 – 41% |
1 – 2 years | 32 – 40% | 32 – 40% |
3 – 5 years | 32 – 42% | 32 – 42% |
6 – 8 years | 33 – 41% | 33 – 41% |
9 – 11 years | 34 – 43% | 34 – 43% |
34 – 44% | 35 – 45% | |
15 – 17 years | 34 – 44% | 37 – 48% |
18 – 44 | 35 – 45% | 39 – 49% |
45 – 64 | 35 – 47% | |
65 – 74 | 35 – 47% | 37 – 51% |
Venous blood with EDTA salts and capillary blood collected in a hematocrit capillary are used for research. In modern analyzers, hematocrit (Hct) is a secondary calculated parameter.
False hematocrit possible at:
- Development of cryoglobulinemia.
- The presence of huge platelets in the sample.
- Increased white blood cell count (more than 50 g/l).
- Hyperglycemia (more than 33.3 mmol/l).
False low in hardware analysis causes:
- RBC agglutination.
- Microerythrocytosis (less than 36 vials).
Clinical and diagnostic value:
An increase in hematocrit is observed when being at high altitude, the presence of neoplasms in the kidneys or their polycystic, chronic lung diseases, erythrocytosis, or conditions leading to a decrease in the volume of plasma circulating in the body – diabetes, non-stop vomiting, increased sweating).
The hematocrit value decreases with anemia or due to an increase in the volume of circulating plasma during pregnancy, overhydration.
Mean erythrocyte hemoglobin (MHC)
Age | Women (pg) | Men (pg) |
Cord blood | 31 – 37 | 31 – 37 |
2 weeks | 30 – 37 | 30 – 37 |
1 month | 29 – 36 | 29 – 36 |
2 months | 27 – 34 | 27 – 34 |
4 months | 25 – 32 | 25 – 32 |
6 months | 24 – 30 | 24 – 30 |
9 months | 25 – 30 | 25 – 30 |
1 year | 24 – 30 | 24 – 30 |
1 – 2 years | 22 – 30 | 22 – 30 |
3 – 8 years | 25 – 31 | 25 – 31 | 9 – 14 years | 26 – 32 | 26 – 32 |
15 – 17 | 26 – 34 | 27 – 32 |
18 – 44 | 27 – 34 | 27 – 34 |
45 – 64 | 27 – 34 | 27 – 35 |
65 – 74 | 27 – 35 | 27 – 34 |
Venous or capillary blood with EDTA salts is used for research.
MHC is used to determine the average hemoglobin content in a single erythrocyte. To calculate the parameter, the following formula is used:
MHC pg \u003d Hb g / l / RBC T / l
The numerator is the total indicator of hemoglobin.
The denominator is the total number of erythrocytes.
The parameter is defined in picograms. To determine the average amount of hemoglobin in erythrocytes, a parameter such as a color index – CPU is also used. It is defined in arbitrary units.
CP = Hb g % * 3 / first 2 digits of RBC count
Or calculated as follows:
CP = MCH pg / 33.4
CP can completely replace MCH. If an automatic hematology analyzer is used for studies that calculates the MCH value, then there is no need to additionally determine the CPU.
Hyperchromia or an increase in MCH greater than 34 pg is not due to an increase in the concentration of hemoglobin in erythrocytes, but is caused by an increase in their volume. A false overestimation of this indicator is possible with errors due to an increased level of hemoglobin and a reduced number of red blood cells. A decrease in MCH to a value of 27 pg or less is called hypochromia.
Clinical and diagnostic value:
- An increase is possible with anemia due to cirrhosis of the liver, hyperchromic or megaloblastic anemia.
- Decrease causes anemia in malignant neoplasms, hypochromic anemia.
Mean erythrocyte hemoglobin concentration MCHC
Age | Women/Men (g/dl) |
Cord blood | 30 – 36 |
2 weeks | 28 – 35 |
1 month | 28 – 36 |
2 months | 28 – 35 |
4 months | 29 -37 |
6 – 12 months | 32 – 37 |
1 – 2 years | 32 – 38 |
3 – 74 years | 32 – 37 902 12 |
The study is carried out using venous or capillary blood with EDTA salts. The indicator characterizes the amount of hemoglobin in the average erythrocyte and is calculated in% according to the following formula:
MCHC = Hb g/l * 10 / Ht %
This is one of the most stable and genetically determined parameters that is not affected by age, gender or race. The concentration of hemoglobin depends on the structure of the cell and does not change throughout life, so the limits of the norm are quite narrow and practically not subject to fluctuations in various pathologies.
There is a clearly defined upper limit for the MCHC. This parameter may be incorrectly determined by inaccurate counting of the number of red blood cells. With it, it is convenient to control the accuracy of the device.
Clinical and diagnostic value:
- An increased value occurs with hypertensive disorders in the water-electrolyte system or hyperchromic anemia.
- A decrease in the values of the indicator is typical for hypotonic disorders of the water and electrolyte balance or hypochromic anemia.
Important! Since the maximum value of hemoglobin solubility in water is 37 g / dl, an excess of an MCHC value of more than 37 indicates the need for a second study. An increased value can also cause hemolysis.
Accurately determine the violations in the water-electrolyte balance using not the absolute values of MCHC, but their dynamics.
MCV
Age | Women (fl) | Men (fl) 9 0212 |
Cord blood | 98 – 118 | 98 – 118 |
2 weeks | 80 – 140 | 80 – 140 |
1 month | 91 – 112 | 91 – 112 |
2 months | 84 – 106 | 84 – 106 |
4 months | 76 – 97 | 76 – 97 |
6 months | 68 – 85 | 68 – 85 |
9 months | 70 – 85 | 70 – 85 |
1 year | 71 – 84 | 71 – 84 |
2 – 5 years | 73 – 85 | 73 – 85 |
5 – 9 years | 75 – 87 | 75 – 87 |
9 – 12 years | 76 – 90 | 76 – 90 |
12 – 14 years | 73 – 95 | 77 – 94 |
15 – 17 years | 80 – 96 | 79 – 95 |
18 – 44 | 81 – 100 | 80 – 99 |
45 – 64 | 81 – 101 | 81 – 101 |
65 – 74 years | 81 – 102 | 81 – 103 |
Almost all modern hematology analyzers can measure this indicator. Data are given in units of femtoliters – fm.
You can also use the formula to calculate:
MCV fl = Hct % * 10 / RBC T/l
The average red blood cell volume changes throughout life. It allows you to quantify microcytosis or macrocytosis. The value of this indicator can be effectively used in the differential diagnosis of anemia.
It is the average volume rather than the diameter of erythrocytes that is more objective in clinical studies. This is due to the fact that the diameter can vary significantly under the influence of normal physiological factors – time of day, physical activity. In automatic analysis, blood is diluted in an isotonic solution, which has constant physico-chemical parameters, ensuring stability when measuring MCV.
MCV rate is 80 to 100 fl. Volume distribution curves are shown in the graph.
The body itself regulates the number of red blood cells and the level of hemoglobin, ensuring their relative constant ratio. The relationship between the number of red blood cells and their average volume is shown in the graph:
Clinical and diagnostic value:
- Less than 80 fl. Microcytic anemia, or accompanied by microcytosis.
- 80 to 100 vials Normocytic anemia, or accompanied by normocytosis.
- Over 10 vials Macrocytic and megablast anemia, as well as those accompanied by macrocytosis.
RBC anisocytosis RDW
Values between 11.6-14.8% are considered normal.
This parameter characterizes the distribution width of erythrocytes. The function of determining this value is incorporated in most modern models of hematological analyzers. Calculated using the formula:
RDW % = SD / MCV fl * 100%
SD is the standard deviation of red blood cell volume from the mean value.
In a healthy person, the normal value may be 12-14%. There are no conditions that can cause this parameter to decrease. Due to differences in blood processing algorithms, even in different devices, different values of this indicator can be obtained.