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Low hgb and hct means: Hemoglobin and Hematocrit – Clinical Methods

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Hemoglobin and Hematocrit – Clinical Methods

Definition

Hemoglobin (Hb) is the protein contained in red blood cells that is responsible for delivery of oxygen to the tissues. To ensure adequate tissue oxygenation, a sufficient hemoglobin level must be maintained. The amount of hemoglobin in whole blood is expressed in grams per deciliter (g/dl). The normal Hb level for males is 14 to 18 g/dl; that for females is 12 to 16 g/dl. When the hemoglobin level is low, the patient has anemia. An erythrocytosis is the consequence of too many red cells; this results in hemoglobin levels above normal.

The hematocrit measures the volume of red blood cells compared to the total blood volume (red blood cells and plasma). The normal hematocrit for men is 40 to 54%; for women it is 36 to 48%. This value can be determined directly by microhematocrit centrifugation or calculated indirectly. Automated cell counters calculate the hematocrit by multiplying the red cell number (in millions/mm3) by the mean cell volume (MCV, in femtoliters). When so assayed, it is subject to the vagaries inherent in obtaining an accurate measurement of the MCV (see Chapter 152).

Both the hemoglobin and the hematocrit are based on whole blood and are therefore dependent on plasma volume. If a patient is severely dehydrated, the hemoglobin and hematocrit will appear higher than if the patient were normovolemic; if the patient is fluid overloaded, they will be lower than their actual level. To assess true red cell mass, independent radionuclide evaluation of the red cells and plasma (by 51Cr and 131I respectively) must be performed.

Technique

Hematocrit

If the hematocrit must be determined quickly, as is often the case when a patient hemorrhages, it may be necessary to measure the hematocrit directly without the use of an automated counter. The materials needed are:

  • Lancets

  • Alcohol prep pads

  • Gauze pads

  • Microhematocrit tubes (heparinized)

  • Sealant (“Seal-Ease,” “Crit-Seal,” etc)

  • Microhematocrit centrifuge

  • Microhematocrit reader

  • If venipuncture is required: tourniquet, syringe, tube containing anticoagulant (EDTA, citrate)

For hematocrits obtained by fingerstick, wipe the fingertip pad of the fourth finger of the nondominant hand with the alcohol prep pad. Make certain the area is allowed to dry. Prick the fingertip with the lancet. Place the hematocrit tube near the incision site and allow the blood to flow via capillary action into the hematocrit tube until it is two-thirds to three-fourths full or to a predesignated mark on the tube. Avoid “milking” the finger if possible; this causes the expression of tissue fluids and may result in a falsely low hematocrit. Always fill at least three tubes. For hematocrits obtained by venipuncture, draw a sample of blood into the tube containing anticoagulant and mix well. Dip the hematocrit tube into the blood and allow the blood to rise to the desired two-thirds to three-quarters level. Because blood cells naturally sediment, a prior thorough mixing of the blood in the tube is necessary to ensure accurate reading.

After cleaning the outside of the hematocrit tubes of excess blood, invert the tube slowly so that the blood migrates just short of the bottom end of the tube. Seal the bottom of the tube with sealant. Make certain that little or no air is interspersed in the column of blood. If the seal is incomplete, leakage will occur during centrifugation and false readings will be obtained.

Place the tubes in a microhematocrit centrifuge and spin for 3 to 5 minutes at high speed. A shorter spin will not allow for complete sedimentation.

Using either a hematocrit reader or any ruled apparatus, measure the length of the column of the packed red cells and divide it by the length of the whole column of blood (cells and plasma), as in . To obtain the hematocrit, multiply this number by 100%. Average all readings obtained from the different microhematocrit tubes.

Figure 151.1

Microhematocrit tube after sedimentation. The hematocrit is a ratio of the packed cells to total volume.

Example: If the column of packed red cells measures 20 mm and the whole blood column measures 50 mm, the hematocrit is 20/50 = 0.4 or (0.4 × 100%) = 40%.

Hemoglobin

Hemoglobin determinations will usually be performed by an automated cell counter from a tube of well-mixed EDTA-anticoagulated blood filled to a predetermined level. In this assay, all forms of hemoglobins are converted to the colored protein cyanomethemoglobin and measured by a colorimeter. An inadequate sample, whether due to insufficient volume or inadequate anticoagulation, may give false readings. If it is necessary to determine the level of anemia quickly, the hematocrit is an easier, more convenient test.

Hemoglobin Electrophoresis

Hemoglobin electrophoresis measures the mobility of hemoglobin in an electric field; it can therefore detect only those abnormalities in hemoglobin that alter the charge. Electrophoretic mobilities are affected by pH and by the medium in which the test is conducted. Screening tests typically use a hemolysate of anticoagulated blood electrophoresed on cellulose acetate at pH 8.6 to 8.8. If necessary, a further electrophoresis in starch gel at pH 6.2 to 6.8 is performed. At that stage, the work will usually be performed by a specialized laboratory.

Hemoglobin electrophoresis will not readily assess situations where there are neutral amino acid substitutions or where the hemoglobin is normal but the constituent chains are not produced in equal numbers (thalassemias). The diagnosis of alpha thalassemia of a mild to moderate degree cannot be made by hemoglobin electrophoresis; the diagnosis of beta thalassemia may be made by inference from an increase in the Hb A2.

A standard electrophoresis would look like .

Figure 151.2

A standard hemoglobin electrophoresis (cellulose acetate, pH 8.6).

Basic Science

The molecular weight of hemoglobin is approximately 64,500 daltons. Hb is composed of two pairs of dissimilar chains, α and β, each defined by a specific amino acid sequence and incorporating an iron-containing heme group. Two α–β dimers combine to form a hemoglobin tetramer. This allows for the “heme–heme” interaction necessary for effective oxygen uptake (deoxyhemoglobin → oxyhemoglobin) and delivery (oxyhemoglobin → deoxyhemoglobin). The oxygen affinity of hemoglobin is a function of this heme–heme interaction and of pH (Bohr effect), and is a measure of how many hemoglobin molecules have oxygen bound to them for a given level of oxygen tension. In a normal individual the major hemoglobin is Hb A, constituting approximately 97% of the total hemoglobin. Variations and/or amino acid substitutions in these chains exist. Some are deleterious to the normal function of hemoglobin, whereas others may have relatively normal oxygen affinity and stability. Hemoglobins containing different types of chains make up the remainder of the hemoglobin content in red cells (α2δ2 = Hb A2 approximately 2%; α2γ2 = Hb F approximately 1%).

Substitutions in the normal hemoglobin amino acid sequence may result in hemoglobins that have different sub-unit interactions and varying affinities for oxygen. For example, a substitution of the sixth amino acid on the beta chain causes Hb S, or sickle hemoglobin. Hb S has a lower oxygen affinity and surrenders its oxygen more readily. Hb F, a normal minor hemoglobin constituent, has a higher oxygen affinity.

If the oxygen dissociation curve is abnormal, the body will adjust the hemoglobin level to ensure adequate oxygen distribution to the tissues. Thus in a rare disease like hemoglobin Hotel Dieu, the difficulty in extracting oxygen from a variant hemoglobin with increased oxygen affinity could result in a lack of oxygen for the tissues (tissue hypoxia) and a compensatory erythrocytosis. The smaller fraction of oxygen released from the hemoglobin is thereby offset by the increased number of hemoglobin molecules. Similarly, in sickle cell anemia, the decreased oxygen affinity allows these patients more tissue oxygen at any given hemoglobin level.

Clinical Significance

Many anemias are detected by routine laboratory screening performed before the patient is symptomatic. When the patient does have symptoms from an abnormality in the hemoglobin level, the symptoms are often a nonspecific weakness or fatigue. The only finding on physical examination may be pallor; additional changes in the nail beds (such as spooning), glossitis (red tongue), or hepatosplenomegaly (enlarged liver or spleen) may give a clue to the etiology of the anemia. Symptoms are usually related to the level of hemoglobin, its abruptness of onset and its duration. A patient with pernicious anemia may feel well at the same level of hemoglobin that would cause severe weakness in a patient with acute gastrointestinal hemorrhage. This is due to volume compensation by plasma and shifts in the oxygen dissociation curve which occur over time.

When first confronted with an abnormal hemoglobin or hematocrit level, the next step is to assess the red cell indices (see Chapter 152), peripheral smear (Chapter 155), and the reticulocyte count (Chapter 156) in light of the patient’s history and physical examination.

References

  1. Adamson JW, Finch CA. Hemoglobin function, oxygen affinity and erythropoietin. Annu Rev Physiol. 1975;37:351. [PubMed: 235878]

  2. Bunn HF. Hemoglobin I. Structure and function. In: Beck WS, Hematology. Cambridge, MA: MIT Press, 1981;129.

  3. Scott AF. et al. The molecular basis of hemoglobin. Am J Hum Genet. 1981;33:129. [PMC free article: PMC1684884] [PubMed: 6258429]

  4. Wallerstein RO. Laboratory evaluation of anemia. West J Med. 1987;146:443. [PMC free article: PMC1307333] [PubMed: 3577135]

Hemoglobin and Hematocrit – Clinical Methods

Definition

Hemoglobin (Hb) is the protein contained in red blood cells that is responsible for delivery of oxygen to the tissues. To ensure adequate tissue oxygenation, a sufficient hemoglobin level must be maintained. The amount of hemoglobin in whole blood is expressed in grams per deciliter (g/dl). The normal Hb level for males is 14 to 18 g/dl; that for females is 12 to 16 g/dl. When the hemoglobin level is low, the patient has anemia. An erythrocytosis is the consequence of too many red cells; this results in hemoglobin levels above normal.

The hematocrit measures the volume of red blood cells compared to the total blood volume (red blood cells and plasma). The normal hematocrit for men is 40 to 54%; for women it is 36 to 48%. This value can be determined directly by microhematocrit centrifugation or calculated indirectly. Automated cell counters calculate the hematocrit by multiplying the red cell number (in millions/mm3) by the mean cell volume (MCV, in femtoliters). When so assayed, it is subject to the vagaries inherent in obtaining an accurate measurement of the MCV (see Chapter 152).

Both the hemoglobin and the hematocrit are based on whole blood and are therefore dependent on plasma volume. If a patient is severely dehydrated, the hemoglobin and hematocrit will appear higher than if the patient were normovolemic; if the patient is fluid overloaded, they will be lower than their actual level. To assess true red cell mass, independent radionuclide evaluation of the red cells and plasma (by 51Cr and 131I respectively) must be performed.

Technique

Hematocrit

If the hematocrit must be determined quickly, as is often the case when a patient hemorrhages, it may be necessary to measure the hematocrit directly without the use of an automated counter. The materials needed are:

  • Lancets

  • Alcohol prep pads

  • Gauze pads

  • Microhematocrit tubes (heparinized)

  • Sealant (“Seal-Ease,” “Crit-Seal,” etc)

  • Microhematocrit centrifuge

  • Microhematocrit reader

  • If venipuncture is required: tourniquet, syringe, tube containing anticoagulant (EDTA, citrate)

For hematocrits obtained by fingerstick, wipe the fingertip pad of the fourth finger of the nondominant hand with the alcohol prep pad. Make certain the area is allowed to dry. Prick the fingertip with the lancet. Place the hematocrit tube near the incision site and allow the blood to flow via capillary action into the hematocrit tube until it is two-thirds to three-fourths full or to a predesignated mark on the tube. Avoid “milking” the finger if possible; this causes the expression of tissue fluids and may result in a falsely low hematocrit. Always fill at least three tubes. For hematocrits obtained by venipuncture, draw a sample of blood into the tube containing anticoagulant and mix well. Dip the hematocrit tube into the blood and allow the blood to rise to the desired two-thirds to three-quarters level. Because blood cells naturally sediment, a prior thorough mixing of the blood in the tube is necessary to ensure accurate reading.

After cleaning the outside of the hematocrit tubes of excess blood, invert the tube slowly so that the blood migrates just short of the bottom end of the tube. Seal the bottom of the tube with sealant. Make certain that little or no air is interspersed in the column of blood. If the seal is incomplete, leakage will occur during centrifugation and false readings will be obtained.

Place the tubes in a microhematocrit centrifuge and spin for 3 to 5 minutes at high speed. A shorter spin will not allow for complete sedimentation.

Using either a hematocrit reader or any ruled apparatus, measure the length of the column of the packed red cells and divide it by the length of the whole column of blood (cells and plasma), as in . To obtain the hematocrit, multiply this number by 100%. Average all readings obtained from the different microhematocrit tubes.

Figure 151.1

Microhematocrit tube after sedimentation. The hematocrit is a ratio of the packed cells to total volume.

Example: If the column of packed red cells measures 20 mm and the whole blood column measures 50 mm, the hematocrit is 20/50 = 0.4 or (0.4 × 100%) = 40%.

Hemoglobin

Hemoglobin determinations will usually be performed by an automated cell counter from a tube of well-mixed EDTA-anticoagulated blood filled to a predetermined level. In this assay, all forms of hemoglobins are converted to the colored protein cyanomethemoglobin and measured by a colorimeter. An inadequate sample, whether due to insufficient volume or inadequate anticoagulation, may give false readings. If it is necessary to determine the level of anemia quickly, the hematocrit is an easier, more convenient test.

Hemoglobin Electrophoresis

Hemoglobin electrophoresis measures the mobility of hemoglobin in an electric field; it can therefore detect only those abnormalities in hemoglobin that alter the charge. Electrophoretic mobilities are affected by pH and by the medium in which the test is conducted. Screening tests typically use a hemolysate of anticoagulated blood electrophoresed on cellulose acetate at pH 8.6 to 8.8. If necessary, a further electrophoresis in starch gel at pH 6.2 to 6.8 is performed. At that stage, the work will usually be performed by a specialized laboratory.

Hemoglobin electrophoresis will not readily assess situations where there are neutral amino acid substitutions or where the hemoglobin is normal but the constituent chains are not produced in equal numbers (thalassemias). The diagnosis of alpha thalassemia of a mild to moderate degree cannot be made by hemoglobin electrophoresis; the diagnosis of beta thalassemia may be made by inference from an increase in the Hb A2.

A standard electrophoresis would look like .

Figure 151.2

A standard hemoglobin electrophoresis (cellulose acetate, pH 8.6).

Basic Science

The molecular weight of hemoglobin is approximately 64,500 daltons. Hb is composed of two pairs of dissimilar chains, α and β, each defined by a specific amino acid sequence and incorporating an iron-containing heme group. Two α–β dimers combine to form a hemoglobin tetramer. This allows for the “heme–heme” interaction necessary for effective oxygen uptake (deoxyhemoglobin → oxyhemoglobin) and delivery (oxyhemoglobin → deoxyhemoglobin). The oxygen affinity of hemoglobin is a function of this heme–heme interaction and of pH (Bohr effect), and is a measure of how many hemoglobin molecules have oxygen bound to them for a given level of oxygen tension. In a normal individual the major hemoglobin is Hb A, constituting approximately 97% of the total hemoglobin. Variations and/or amino acid substitutions in these chains exist. Some are deleterious to the normal function of hemoglobin, whereas others may have relatively normal oxygen affinity and stability. Hemoglobins containing different types of chains make up the remainder of the hemoglobin content in red cells (α2δ2 = Hb A2 approximately 2%; α2γ2 = Hb F approximately 1%).

Substitutions in the normal hemoglobin amino acid sequence may result in hemoglobins that have different sub-unit interactions and varying affinities for oxygen. For example, a substitution of the sixth amino acid on the beta chain causes Hb S, or sickle hemoglobin. Hb S has a lower oxygen affinity and surrenders its oxygen more readily. Hb F, a normal minor hemoglobin constituent, has a higher oxygen affinity.

If the oxygen dissociation curve is abnormal, the body will adjust the hemoglobin level to ensure adequate oxygen distribution to the tissues. Thus in a rare disease like hemoglobin Hotel Dieu, the difficulty in extracting oxygen from a variant hemoglobin with increased oxygen affinity could result in a lack of oxygen for the tissues (tissue hypoxia) and a compensatory erythrocytosis. The smaller fraction of oxygen released from the hemoglobin is thereby offset by the increased number of hemoglobin molecules. Similarly, in sickle cell anemia, the decreased oxygen affinity allows these patients more tissue oxygen at any given hemoglobin level.

Clinical Significance

Many anemias are detected by routine laboratory screening performed before the patient is symptomatic. When the patient does have symptoms from an abnormality in the hemoglobin level, the symptoms are often a nonspecific weakness or fatigue. The only finding on physical examination may be pallor; additional changes in the nail beds (such as spooning), glossitis (red tongue), or hepatosplenomegaly (enlarged liver or spleen) may give a clue to the etiology of the anemia. Symptoms are usually related to the level of hemoglobin, its abruptness of onset and its duration. A patient with pernicious anemia may feel well at the same level of hemoglobin that would cause severe weakness in a patient with acute gastrointestinal hemorrhage. This is due to volume compensation by plasma and shifts in the oxygen dissociation curve which occur over time.

When first confronted with an abnormal hemoglobin or hematocrit level, the next step is to assess the red cell indices (see Chapter 152), peripheral smear (Chapter 155), and the reticulocyte count (Chapter 156) in light of the patient’s history and physical examination.

References

  1. Adamson JW, Finch CA. Hemoglobin function, oxygen affinity and erythropoietin. Annu Rev Physiol. 1975;37:351. [PubMed: 235878]

  2. Bunn HF. Hemoglobin I. Structure and function. In: Beck WS, Hematology. Cambridge, MA: MIT Press, 1981;129.

  3. Scott AF. et al. The molecular basis of hemoglobin. Am J Hum Genet. 1981;33:129. [PMC free article: PMC1684884] [PubMed: 6258429]

  4. Wallerstein RO. Laboratory evaluation of anemia. West J Med. 1987;146:443. [PMC free article: PMC1307333] [PubMed: 3577135]

Complete blood count

Dear patients! When you receive a complete blood count form, the question arises: “What do these indicators mean?” In this article you will find an explanation of the main indicators of the general blood test. Warning: to explain the results of a blood test and make a diagnosis, a specialist consultation (physician) is necessary!

Normal values:

WBC – leukocytes – from 4. 0 to 10.0 billion / liter,

Lymph – lymphocytes – from 0.8 to 4.0 billion / liter,

Mid- (content of a mixture of monocytes, eosinophils, basophils and immature cells) –

from 0.1 to 1.5 billion / liter,

Gran – granulocytes – from 2, 0 to 7.0 billion/liter,

Lymph% – lymphocytes – from 20 to 40%,

Mid% – (content of a mixture of monocytes, eosinophils, basophils and immature cells) – from 3 to 15%,

Gran% – granulocytes – from 50 to 70%, 90 005

HGB – hemoglobin – 20-160 g / liter

RBC – erythrocytes – from 3.5 to 5.5 trillion / liter,

HCT – hematocrit – 37.0 to 54.0,

MCV – mean erythrocyte volume – 80.0 to 100.0 femtoliters,

MCH – mean erythrocyte hemoglobin – 27.0 to 34.0 picograms,

90 002 MCHC – mean hemoglobin concentration in erythrocyte – from 320 to 360,

RDW – CV – erythrocyte distribution width – from 11.0 to 16.0,

RDW – SD – erythrocyte distribution width (standard deviation) –

from 35. 0 to 56.0, 9 0005

PLT – platelets – from 180 to 320 billion / liter,

MPV – mean volume of erythrocyte – from 6.5 to 12.0,

PDW – relative platelet distribution width by volume – from 9.0 to 17.0,

PCT – thrombocrit (proportion of platelets in total volume of whole blood) from 0.108 to 0.282

ESR – ESR – less than 12, but normal indicators can vary greatly depending on age and gender.

The value of the indicators:

WBC – leukocytes. Leukocytes (white blood cells) protect the body from infections (bacteria, viruses, parasites. A high level of leukocytes indicates the presence of a bacterial infection, and a decrease in the number of leukocytes occurs when taking certain medications, blood diseases.

Lymph – lymphocytes – from 0.8 to 4.0 billion / liter. A lymphocyte is a type of white blood cell that is responsible for developing immunity and fighting germs and viruses. An increase in the number of lymphocytes (lymphocytosis) occurs in viral infectious diseases, as well as in blood diseases (chronic lymphocytic leukemia, etc. ). A decrease in the number of lymphocytes (lymphopenia) occurs in severe chronic diseases, taking certain drugs that suppress the immune system (corticosteroids, etc.).

Mid. Monocytes, eosinophils, basophils and their precursors circulate in the blood in small amounts, so these cells are often combined into one group, which is designated as MID. These types of blood cells also belong to leukocytes and perform important functions (the fight against parasites, bacteria, the development of allergic reactions, etc.)

Gran – granulocytes. These are white blood cells that contain granules (granular white blood cells). Granulocytes are represented by 3 types of cells: neutrophils, eosinophils and basophils. These cells are involved in the fight against infections, in inflammatory and allergic reactions.

Lymph% – lymphocytes – 20 to 40%,

Mid% – (mixture of monocytes, eosinophils, basophils and immature cells) – 3 to 15%,

Gran% – granulocytes – 50 to 70%,

H GB – hemoglobin. A special protein that is found in red blood cells and is responsible for transporting oxygen to organs. A decrease in hemoglobin levels (anemia) leads to oxygen starvation of the body. An increase in hemoglobin levels, as a rule, indicates a high number of red blood cells, or dehydration.

RBC – erythrocytes. Red blood cells perform an important function of supplying the tissues of the body with oxygen, as well as removing carbon dioxide from the tissues, which is then released through the lungs. If the level of red blood cells is below normal (anemia), the body receives insufficient amounts of oxygen. If the level of red blood cells is higher than normal (polycythemia, or erythrocytosis), there is a risk that the red blood cells stick together and block the movement of blood through the vessels (thrombosis).

HCT – hematocrit. An indicator that reflects how much blood is occupied by red blood cells. Elevated hematocrit occurs with erythrocytosis (increased number of red blood cells in the blood), as well as with dehydration. A decrease in hematocrit indicates anemia (a decrease in the level of red blood cells in the blood), or an increase in the amount of the liquid part of the blood.

MCV is the mean volume of an erythrocyte. Red blood cells with a small average volume are found in microcytic anemia, iron deficiency anemia, etc. Red blood cells with an increased average volume are found in megaloblastic anemia (anemia that develops when there is a deficiency of vitamin B12 or folic acid in the body).

MCH – the average content of hemoglobin in the erythrocyte. A decrease in this indicator occurs with iron deficiency anemia, an increase – with megaloblastic anemia (with a deficiency of vitamin B12 or folic acid).

MCHC is the average concentration (saturation) of hemoglobin in an erythrocyte. A decrease in this indicator occurs with iron deficiency anemia, as well as with thalassemia (a congenital blood disease). There is practically no increase in this indicator.

RDW – CV – erythrocyte distribution width. The indicator is used in the laboratory assessment of anemia, inflammation, oncopathology, diseases of the cardiovascular system and the gastrointestinal tract.
RDW – SD – erythrocyte distribution width (standard deviation).

PLT – platelets. Small plates of blood that are involved in the formation of a blood clot and prevent blood loss in case of damage to blood vessels. An increase in the level of platelets in the blood occurs in some blood diseases, as well as after operations, after the removal of the spleen. Decreased platelet levels occur in some congenital blood disorders, aplastic anemia (a malfunction of the bone marrow that produces blood cells), idiopathic thrombocytopenic purpura (destruction of platelets due to an overactive immune system), cirrhosis of the liver

MPV – mean erythrocyte volume. An increase in MPV can be provoked by diabetes mellitus, thrombocytodystrophy, blood pathologies (systemic lupus), splenectomy, alcoholism, myeloid leukemia, vascular atherosclerosis, thalassemia (a genetic disorder in the structure of hemoglobin), May-Hegglin syndrome, posthemorrhagic anemia. Below the norm, this indicator falls due to radiation therapy, with cirrhosis of the liver, anemia (plastic and megaloblastic), Wiskot-Aldrich syndrome.

PDW – relative platelet distribution width by volume. This indicator is indirect, taken into account in a complex of other indicators.

PCT – thrombocrit (the proportion of platelets in the total volume of whole blood). The main purpose of this study is to assess the risk of developing thrombosis or, conversely, bleeding, which in both cases can pose a threat to the life of the patient.

ESR – ESR. A non-specific indicator that rises in many pathological conditions of completely different origins (infectious diseases, blood diseases, tumors, inflammatory processes, autoimmune diseases).

You do not need to sign up for a general blood test! Blood sampling is carried out from 7.30 to 12.00.

Complete blood count | decoding, indicators and norms of the UAC

Complete or clinical blood test is a detailed study prescribed by a doctor when a patient contacts and complains of feeling unwell.

Contains information about the nature of hematopoiesis, reflecting the general state of the body, the values ​​of quantitative and qualitative changes in the composition of the blood.

Biochemical results usually make it possible to determine the diagnosis immediately or after additional examinations: ultrasound, X-ray.

Blood transports various substances between tissues, organs and systems, ensuring the unity of the body. Thus, the processes occurring in different tissues and organs are reflected in the state of the blood.

Blood consists of a liquid part – plasma and formed elements – leukocytes, platelets, erythrocytes, each type of which has functions, for example, leukocytes are responsible for protecting immunity, platelets – for clotting, erythrocytes provide the body with oxygen and carbon dioxide.

Analysis can identify possible diseases, in which case the composition of the blood changes. Clinical analysis sometimes allows you to identify the disease at an early stage, when the symptoms of the disease do not even appear. Clinical analysis helps clients understand the course of the disease, determine the intensity of the pathological process, so it is used as a diagnosis of inflammation, allergies, and diseases. A repeated general analysis (CLA) is carried out as prescribed by a doctor in order to evaluate the effectiveness of treatment and, if necessary, adjust it. Hematological diseases require a primary study of cells for preventive purposes.

Deciphering the abbreviation of the general blood test

Now the English abbreviation is used on the forms with the results of the KLA, which means:

  • WBC – white blood cells – white blood cells – Leukocytes;
  • RBC – red blood cells – red blood cells – Erythrocytes;
  • HGB – hemoglobin – Hemoglobin;
  • HTC – hematocrit – Hematocrit;
  • MCV – mean corpuscular volume – The average volume of erythrocytes;
  • MCH – mean concentration hemoglobin – The average content of hemoglobin in an erythrocyte;
  • MCHC – mean corpuscular hemoglobin concentration – Mean concentration of hemoglobin in an erythrocyte;
  • RDW – red cell distribution – Red blood cell distribution index;
  • PLT – platelets – platelets;
  • MPV – mean platelets volume
  • PTC – Thrombocrit – Thrombocrit.

Indicators of the general blood test

Complete blood count contains mandatory parameters. A pediatrician, therapist or other specialists may refer the patient to an extended clinical blood test, which additionally includes the necessary indicators.

Hemoglobin

Hemoglobin is a protein found in red blood cells. It delivers oxygen from the lungs, and carbon dioxide, on the contrary, to the lungs. It contains iron, which makes red blood cells red.

Level is a very important indicator of him. Due to a decrease in its amount, the body receives less oxygen, which is necessary for its life.

For men, it is considered normal – from 130-160 g/l, for women – 120-140 g/l. The saturation of this element in newborn children significantly exceeds the norm of adults. However, in the first weeks it gradually decreases.

When the hemoglobin value is below normal, then anemia is diagnosed, a low level can also indicate overhydration of the body due to increased fluid intake. Elevated hemoglobin can be observed with thickening of the blood due to a violation of the function of coagulation or the use of diuretic drugs. Dehydration of the body can be caused not only by pathology, but also by increased physical exertion or extreme heat. An elevated hemoglobin level is a typical sign of erythremia – impaired blood formation, an increased number of red blood cells. Hemoglobin can also increase due to diseases of the respiratory system against the background of a constant lack of oxygen.

red blood cells

Erythrocytes are red blood cells responsible for metabolic processes. The blood is red in color, due to the high content of red blood cells, compared to other formed elements. Red blood cells contain hemoglobin, so they are involved in the process of oxygen metabolism in the body.

Norms for men – 4-5 * 1012 per liter of blood, for women – 3.9-4.7 * 1012, which depend on the laboratory.

With anemia, bleeding, pregnancy, hyperhydration, the content of erythrocytes in the blood decreases. Excess, as a rule, indicates erythremia, such tumor formations as a kidney cyst or dropsy of the renal pelvis, dehydration and fluid loss with sweat, vomiting, diarrhea, when the blood thickens.

The average volume of erythrocytes MCV – mean corpuscular volume – the norm for men is 80-95 and for women – 80-100.

The mean concentration of hemoglobin in an erythrocyte MCH – mean concentration hemoglobin – this indicator increases with hypothyroidism, anemia of an autoimmune nature, B12-deficiency anemia, liver pathologies, alcohol dependence, and decreases due to iron deficiency anemia or decreased thyroid function.

The average concentration of hemoglobin in erythrocytes MCHC – mean corpuscular hemoglobin concentration – an increase in this indicator almost always indicates a hardware error, and its decrease indicates iron deficiency anemia.

Hematocrit

Hematocrit – the ratio of formed elements to the total volume of blood in percent.

An increase in hematocrit occurs as a result of:

  • dehydration;
  • peritonitis;
  • extensive burns;
  • polycythemia.

A decrease in hematocrit is observed against the background of:

  • anemia and iron deficiency;
  • heart disease;
  • vascular and kidney pathologies;
  • chronic hyperazotemia – increased nitrogen levels in the blood

color indicator

The color index of blood is calculated according to a formula in which the hemoglobin level and the number of erythrocytes are correlated. Normally, the color index is close to one (0.85-1.05). Anemia leads to a deviation of the indicator. If the color index is below normal, then this indicates iron deficiency anemia, when hemoglobin is reduced more than the number of red blood cells. Anemia of another type is characterized by a color index above the norm, in this case, the number of red blood cells is reduced more than hemoglobin.

Reticulocytes

Reticulocytes are young, immature erythrocytes that are always present in the blood, since the process of formation of erythrocytes in the blood is continuous. Norm: 0.2-1% or 2-10 reticulocytes out of 1000 erythrocytes. If reticulocytes are more than normal, then the body feels the need to increase red blood cells, for example, due to large blood loss. In the presence of anemia, radiation sickness, oncology (if metastases have affected the bone marrow), some kidney diseases are characterized by a reduced level of reticulocytes. Determining the RET indication is required for bone marrow transplantation, chemotherapy, as well as for assessing the processes of hematopoiesis, therapy with drugs containing iron, folic acid, vitamin B12, erythropoietin.

platelets

Platelets are responsible for blood clotting. They provide not only hemostasis, but also the body’s immunity during infection. Normal platelet content: 180-320*109 per liter. A decrease in this level may indicate the presence of an inflammatory process in the body, an autoimmune disease, leukemia; AIDS, alcohol poisoning, drugs, chemicals, aplastic anemia, bone marrow diseases.

An increase occurs after blood loss and surgery, and is also observed in malignant neoplasms, spleen atrophy, colitis, tuberculosis, osteomyelitis, joint diseases, liver cirrhosis, myelofibrosis.

Leukocytes

Leukocytes are white blood cells that perform a protective function. The norm of their content is in the range of 4-9*109 per litre.

A high level of leukocytes is observed in infectious diseases caused by bacteria, inflammatory processes, allergic reactions. Their number increases as a result of recent stress, bleeding, as well as due to tumor processes and some other pathologies.

The depressed state of the immune system causes a decrease in leukocytes due to weight loss, severe toxicosis, sepsis, diseases of the hematopoietic organs, radiation sickness, autoimmune diseases, immunodeficiency, leukemia, viral infections such as influenza, measles, rubella, as well as due to the use of sulfonamides, non-steroidal anti-inflammatory drugs.

Not only the total number of leukocytes is important, but also their five types – neutrophils, eosinophils, basophils, lymphocytes and monocytes, which have different functions, so it is important to know their ratio in the blood, that is, the leukocyte formula.

Pathological leukocytosis is observed in:

  • purulent inflammatory diseases;
  • severe burns;
  • the use of the hormone insulin;
  • malignant tumors;
  • epilepsy;
  • severe poisoning;
  • allergies.

Neutrophils

Neutrophils are non-specific immune response cells that have bactericidal and detoxifying functions. In the inflammatory process, there is an increase in the number of mature neutrophils that are produced by the bone marrow. First, a myelocyte is formed, which then becomes a metamyelocyte, then the stage of a stab neutrophil begins. A mature neutrophil is segmented. In the normal state of the body, myelocytes and metamyelocytes in the blood should be absent. Segmented neutrophils should make up 47-72% of the total number of leukocytes, and stab – 1-6%. When immunity is weakened, the proportion of stab nuclei increases, in this case the body sends still immature neutrophils to fight the infection. An analysis with such a result is called a stab shift.

Stress, intoxication, inflammation, bacterial infection, cancer also increase the number of neutrophils in the blood.

Eosinophils

Eosinophils neutralize immune complexes caused by foreign allergens. The norm of eosinophils is 1-5% of the total. An increase in this indicator indicates an allergic reaction or a parasitic infection (primarily an infection with worms).

Basophils

The normal content in the blood is: 0-1% of the total.

Lymphocytes

Lymphocytes are the main cells of the immune system that recognize and destroy the invading agent. This is how the body fights viruses. The normal level of lymphocytes is 19-37% of the total. This figure is higher in children than in adults. At the age of one month to two years, the main type of leukocytes is lymphocytes. By the age of five, the number of leukocytes is already comparable to the number of neutrophils. Children at the age of 15 still have more lymphocytes than adults.

With a viral infection, with toxoplasmosis, tuberculosis, syphilis, there is an increased content of lymphocytes in the blood. A reduced number of lymphocytes indicates HIV infection and a depressed state of the immune system.

Monocytes

Monocytes stay in the blood for about 30 hours. Then they move from the bloodstream to tissues, where they turn into macrophages in order to finally destroy bacteria and tissues that have died from inflammation. The norm of monocytes is 3-11% of the total. An increased number of monocytes is a specific sign of mononucleosis, and is also characteristic of tuberculosis, sarcoidosis, syphilis, rheumatoid arthritis, indolent and long-term diseases.

ESR – erythrocyte sedimentation rate

Compared to plasma, red blood cells are a heavier fraction of the blood. Therefore, when the test tube is vertical, its contents are divided into two parts: in the lower part – thick and dark erythrocytes, and in the upper part – light plasma. The erythrocyte sedimentation rate is measured in mm/hour. Norm: for men – 2-10 mm / hour, for women – 2-15 mm / hour. In children, pregnant women and the elderly, normal values ​​​​are different.

The erythrocyte sedimentation rate increases with an increase in their mass, that is, there is a strong bonding between them. The most common cause of such bonding is an inflammatory process. As a rule, the stronger the inflammation, the higher the ESR.

With an increase in ESR, autoimmune diseases occur in the body, blood, liver and biliary tract, and there may also be the following diseases:

  • heart attack;
  • stroke;
  • tuberculosis;
  • malignant tumors;
  • thyrotoxicosis;
  • diabetes mellitus.

Preparing for a complete blood count

  1. Two weeks before the test, it is important to stop taking medicines for laboratory testing. If the medications taken are vital, then the doctor adjusts the treatment, because some drugs can affect blood parameters.
  2. The day before the study, alcohol, fatty, spicy and fried foods should be excluded, physical and emotional stress should be avoided, and KLA should not be taken after an x-ray examination, physiotherapy, sunbathing.
  3. Dinner on the eve of the study no later than 22.00.
  4. It is advisable to donate blood for general analysis in the morning on an empty stomach. Biological material for both capillary and venous blood can serve. Before this, you can not smoke, drink coffee, tea. Drinking water is allowed in a volume of not more than 0.5 liters. If the analysis is taken during the day, then after the last meal, approximately 5 hours should pass.
  5. Women, undergoing a routine examination, it is advisable to postpone the delivery of the KLA until the end of menstruation.

The procedure for taking the KLA

  1. Blood sampling for general analysis in both a child and an adult is almost the same.