Why take a general blood test and how to decipher its results

General blood test and its interpretation

The indicators of a general fasting blood test are assessed (the price of the test is available to everyone) by quantity, percentage and quality. They evaluate “red blood cells” - red blood cells, which, with the help of hemoglobin, carry oxygen throughout the body. Also, the indicators of the general blood test of a child and an adult, which are deciphered in children and adults at prices below average, are carried out by us, help to evaluate all types of white blood cells - leukocytes and blood platelets - platelets. The former are responsible for many processes in the body related to the functioning of the immune system, and the latter are responsible for the ability of blood to clot.

Neutrophils

{banner_banstat1}
These cells occupy 50-70% of the total number of white blood cells. A significant increase in their number can occur as a natural reaction of the body when:

inflammation;
intoxication with heavy metals;
infections caused by various viruses, microorganisms or fungi;
the appearance of neoplasms;
heart attacks of various internal organs;
tissue necrosis;
stressful situations or excessive physical exertion;
diabetes mellitus;
postoperative conditions.

A decrease in the number of neutrophils below normal is observed when:

influenza, hepatitis, smallpox, rubella;
weakened immune system;
anaphylactic shock;
increased levels of thyroid hormones;
diseases of the circulatory system, anemia, leukemia;
congenital or drug-induced neutropenia.

General blood test: interpretation in adults

General clinical blood test: the norm of red blood cells is from 3.7 to 5.1 per 10 to 12 cells per 1 liter, the concentration of hemoglobin in them is 120-140 g/l in women and 130-160 g/l in men.

The blood test is general and its interpretation requires an assessment of the shape of the red blood cells, which normally represent a biconcave disc. Changes in these indicators may indicate iron deficiency and anemia, or blood thickening. Indicators of a general blood test and their norm help determine the type of anemia, its possible cause, etc.

The number of “young” red blood cells - reticulocytes - in a general fasting blood test is in the range of 0.2-1.2%. They increase with increased hematopoiesis, accelerated destruction of mature red blood cells (hemolysis) and decrease with anemia, kidney disease, thyroid disease, consequences of radiation exposure, etc.

Lymphocytes

{banner_banstat2}
The norm of cells that provide the immune response and memory of the body, recognizing foreign bodies, is 20-40% of the total number of wbc.

An increase in their number is observed in the following situations:

for severe infectious diseases: HIV, toxoplasmosis, viral infections and hepatitis, whooping cough and others;
diseases of the circulatory system;
severe intoxication due to poisoning with toxic substances (arsenic, lead, tetrachloroethane);
taking medications such as narcotic painkillers, phenytoin, valproic acid.

A decrease in the number of lymphocytes is noted:

for some congenital diseases;
acute infections;
immunodeficiency;
renal failure;
diseases of the lymphatic system;
aplastic anemia;
milliary tuberculosis.

General blood test interpretation: ESR and leukocytes

An increase in ESR, or erythrocyte sedimentation rate (normally 1-10 mm per hour in men and 2-15 mm/hour in women), helps detect signs of an inflammatory response.

The total number of leukocytes is 4-9 per 10 to the 9th power of cells per liter. The optimal ratio of fasting blood count indicators is normal for different types of leukocytes:

· For neutrophils - band 1-6% - segmented 47-72%

· For basophils 0-1%

· For monocytes 2-9%

· For eosinophils 0-5%

· For lymphocytes 18-40%

Changing the number of different types of white blood cells can help determine the presence of a viral or bacterial infection, an inflammatory reaction, atypical changes in cells in the bone marrow, a parasitic disease, an allergy, etc.

What do violations of norms in a blood test indicate?

Violations of the above OAC norms in children may indicate either a slight illness in the child or the development of a serious and sometimes fatal disease.

Only a doctor can evaluate the totality of all factors, including the full picture of the analysis performed, the general condition of the baby, his age, the presence or absence of somatic diseases or congenital conditions, etc.

Do not try to independently evaluate the results obtained and draw conclusions, much less self-medicate. Delay in receiving quality and professional treatment can cost your child his life.

Leukemia

Leukemia refers to cancers of the blood, the causes of which have not yet been fully determined. Leukemia (or leukemia) is a malignant tumor process in the hematopoietic and lymphatic tissue.

The likelihood of a complete recovery and return of the child to normal life directly depends on the timing of seeking medical help. What could be a signal that there are serious problems? Deviations in the general blood test:

a significant drop in red blood cell levels;
decreased platelet levels (2.5 times lower than normal);
drop in hemoglobin level (sometimes 3 times);
depending on the form of the disease, the leukocyte count can be highly elevated or, conversely, catastrophically low;
a sharp increase in ESR.

Allergic manifestations

Any allergic manifestations, from the most minor to those requiring urgent medical attention, are reflected in the indicators of a general blood test.

The presence of foreign allergens in the body does not go unnoticed.

the number of leukocytes increases;
ESR increases slightly;
the number of eosinophils (one of the types of leukocytes), which are considered the main indicator of allergies in a blood test, increases sharply;
the level of ferritin, a specific protein, increases as the body’s response to the inflammatory process;
all other indicators remain practically within normal limits.

Photo source: shutterstock.com

Thrombocytosis

A number of diseases, the main indicator of which can be considered a change in the composition of the blood, where platelets are significantly increased (in some cases, the level of platelets can be increased by 3-4 times). Among the most common causes of thrombocytosis may be:

presence of tumor diseases;
severe blood loss;
acute inflammation or infectious diseases;
disruption (at the gene level) of the production of activated protein C, which ensures the fluid properties of blood.

Worm infestations

Infection with parasites, if not treated in a timely manner, can have very serious consequences. Some specialists from European medical organizations believe that the presence of helminthic infestation (worms) in the human body reduces its lifespan by 10-15 years.

If infection with parasites (for example, Giardia) occurs, this immediately affects the composition of the child’s blood. The child’s body is especially sensitive to this type of infection, so based on the results of a child’s blood test, the following conclusions can be drawn:

hemoglobin levels decrease;
the level of eosinophils increases;
there is a significant increase in ESR.

Atypical leukocytes

The appearance of atypical leukocytes in a child’s analysis (differences in shape, size, color, change in nucleus) may indicate:

about the presence of a viral or bacterial infection in the child’s body (for example, sore throat);
about intoxication of the body;
about the development of pathological tumor processes or the presence of genetic pathology.

Hypochromic anemia

Hypochromia or hypochromic anemia is a violation of the color of a blood smear (red blood cells) taken for analysis. Hypochromia is closely related to another disorder, microcytosis - the predominance of small red blood cells in the blood.

Such violations indicate the presence of a systemic disease that provokes the appearance of one of the types of anemia.

Mononucleosis

Mononucleosis is an acute viral disease that requires urgent medical treatment.

the level of lymphocytes increases (by more than 40%);
the level of monocytes increases (by more than 10%).

General clinical blood test for a child interpretation

Children's bodies continue to develop and adapt to the changes associated with growing up. Therefore, the data of a general fasting blood test in children of different age groups are different.

A general clinical blood test for a child under one year of age does not differ in price from an adult. Interpretation: Number of erythrocytes - 4.3-7.6 per 10 to 12 cells/l, reticulocytes - 3-51%, hemoglobin concentration - 180-240 g/l, platelets - 180-490 per 10 to 9 cells/ l, leukocyte level – 8.5-24.5 per 10 to 9 degrees, ESR – 2-4 mm/hour.

The ratio of types of leukocytes: eosinophils - 0.5-6%, basophils - 0-1%, band netrophils 1-17%, and segmented ones - 45-80%, lymphocytes 12-36%, monocytes - 2-12%;

General blood test in children (the price is quite affordable) older than 1 year:

The number of erythrocytes decreases - 3.6-4.9 per 10 in 12 cells/l, hemoglobin - 110-135 g/l, reticulocytes - 3-15%, leukocytes - 6.0-12.0 per 10 in 9 degrees. ESR becomes closer to adult levels - 4-12 mm/hour.

Eosinophils

{banner_banstat3}
The normal level of eosinophils should not exceed 1-5% of the total wbc.

A blood test shows an increased content of these cells in the following cases:

for allergic reactions, manifested in the form of bronchial asthma, hay fever, eczema;
for drug allergies;
diseases caused by protozoa;
for parasitic infestations;
acute phases of severe infectious diseases;
malignant neoplasms;
lung diseases: sarcoidosis, pneumonia and others.

A decrease in the number of eosinophils is observed:

in stressful situations, physical stress;
at the initial stages of inflammatory processes;
for injuries, surgical interventions;
for burns;
in case of intoxication with heavy metals or chemical compounds;
on the first day after myocardial infarction.
with severe purulent processes.

Monocytes

{banner_banstat4}
The normal level of monocytes in the blood is 3-9%.

An increased content of these cells manifests itself as:

granulomatosis;
inflammation of the larynx or nasopharynx;
infections caused by various viruses or fungi;
blood diseases;
pain in the right hypochondrium caused by an increase in liver size.

A lack of monocytes develops against the background of iron deficiency anemia, lack of B vitamins, folic acid and is observed in the following situations:

with aplastic anemia;
the presence of purulent infections;
during surgical interventions, childbirth;
while taking corticosteroids and chemotherapy.

An extensive study of the qualitative and quantitative composition of blood, which provides characteristics of red blood cells and their specific indicators (MCV, MCH, MCHC, RDW), leukocytes and their varieties in percentage (leukocyte formula) and platelets.

Microscopy of the leukocyte formula is always performed as part of the analysis.

English synonyms

Complete blood count (CBC) with differential.

Research method

SLS (sodium lauryl sulfate) - method
Conductometric method
Microscopy
Flow cytometry

What biomaterial can be used for research?

Venous, capillary blood.

How to properly prepare for research?

Eliminate alcohol from your diet for 24 hours before the test.
Children under 1 year of age should not eat for 30-40 minutes before the test.
Children aged 1 to 5 years should not eat for 2-3 hours before the test.
Do not eat for 8 hours before the test; you can drink clean still water.
Avoid physical and emotional stress for 30 minutes before the test.
Do not smoke for 30 minutes before the test.

General information about the study

A clinical blood test with a leukocyte formula is one of the most frequently performed tests in medical practice. Today, this study is automated and allows you to obtain detailed information about the quantity and quality of blood cells: red blood cells, leukocytes and platelets. From a practical point of view, the doctor should primarily focus on the following parameters of this analysis:

Hb (hemoglobin) – hemoglobin;
MCV (mean corpuscular volume) – average volume of an erythrocyte;
RDW (RBC distribution width) – distribution of red blood cells by volume;
total number of red blood cells;
total platelet count;
total leukocyte count;
leukocyte formula - the percentage of different leukocytes: neutrophils, lymphocytes, monocytes, eosinophils and basophils.

Determining these parameters makes it possible to diagnose conditions such as anemia/polycythemia, thrombocytopenia/thrombocytosis and leukopenia/leukocytosis, which can either be symptoms of a disease or act as independent pathologies.

When interpreting the analysis, the following features should be taken into account:

In 5% of healthy people, blood test results deviate from the accepted reference values. On the other hand, the patient may show a significant deviation from his usual indicators, which at the same time remain within the accepted norms. For this reason, test results must be interpreted in the context of each individual's individual normal performance.
Blood counts vary by race and gender. Thus, in women the number and quality characteristics of red blood cells are lower, and the number of platelets is higher than in men. For comparison: men – Hb 12.7-17.0 g/dl, erythrocytes 4.0-5.6×1012/l, platelets 143-332×109/l, women – Hb 11.6-15.6 g /dl, red blood cells 3.8-5.2×1012/l, platelets 169-358×109/l. In addition, hemoglobin, neutrophils and platelets are lower in dark-skinned people than in white people.

What is the research used for?

For diagnosis and control of treatment of many diseases.

When is the study scheduled?

During a preventive examination;
if the patient has complaints or symptoms of any disease.

What do the results mean?

Reference values

Component	Floor	Age	Reference values
White blood cells (WBC), *10^9/l		0-1 year	6.0 — 17.5
		1-2 years	6.0 — 17.0
		2-4 years	5.5 — 15.5
		4-6 years	5.0 — 14.5
		6-10 years	4.5 — 13.5
		10-16 years	4.5 — 13.0
		More than 16 years	4.0 — 10.0
Red blood cells (RBC), *10^12/l	female	0-14 days	3.9 — 5.9
	male	0-14 days	3.9 — 5.9
	male	1-4 months	3.5 — 5.1
	female	1-4 months	3.5 — 5.1
	male	4-6 months	3.9 — 5.5
	female	4-6 months	3.9 — 5.5
	male	6-9 months	4.0 — 5.3
	female	6-9 months	4.0 — 5.3
	male	9-12 months	4.1 — 5.3
	female	9-12 months	4.1 — 5.3
	male	1-3 years	3.8 — 4.8
	female	1-3 years	3.8 — 4.8
	male	3-6 years	3.7 — 4.9
	female	3-6 years	3.7 — 4.9
	male	6-9 years	3.8 — 4.9
	female	6-9 years	3.8 — 4.9
	male	9-12 years	3.9 — 5.1
	female	9-12 years	3.9 — 5.1
	male	12-15 years	4.1 — 5.2
	female	12-15 years	3.8 — 5.0
	male	15-18 years old	4.2 — 5.6
	female	15-18 years old	3.9 — 5.1
	male	18-45 years old	4.3 — 5.7
	female	18-45 years old	3.8 — 5.1
	male	45-65 years	4.2 — 5.6
	female	45-65 years	3.8 — 5.3
	male	More than 65 years	3.8 — 5.8
	female	More than 65 years	3.8 — 5.2
	female	14-30 days	3.3 — 5.3
	male	14-30 days	3.3 — 5.3
Hemoglobin (HGB), g/l	male	0-14 days	134 — 198
	female	0-14 days	134 — 198
	male	14-30 days	107 — 171
	female	14-30 days	107 — 171
	male	1-2 months	94 — 130
	female	1-2 months	94 — 130
	male	2-4 months	103 — 141
	female	2-4 months	103 — 141
	male	4-6 months	111 — 141
	female	4-6 months	111 — 141
	male	6-9 months	114 — 140
	female	6-9 months	114 — 140
	male	9-12 months	113 — 141
	female	9-12 months	113 — 141
	male	1-5 years	110 — 140
	female	1-5 years	110 — 140
	male	5-10 years	115 — 145
	female	5-10 years	115 — 145
	male	10-12 years	120 — 150
	female	10-12 years	120 — 150
	male	12-15 years	120 — 160
	female	12-15 years	115 — 150
	male	15-18 years old	117 — 166
	female	15-18 years old	117 — 153
	male	18-45 years old	132 — 173
	female	18-45 years old	117 — 155
	male	45-65 years	131 — 172
	female	45-65 years	117 — 160
	male	More than 65 years	126 — 174
	female	More than 65 years	117 — 161
Hematocrit (HCT), %	male	0-14 days	41 — 65
	female	0-14 days	41 — 65
	male	14-30 days	33 — 55
	female	14-30 days	33 — 55
	male	1-2 months	28 — 42
	female	1-2 months	28 — 42
	male	2-4 months	32 — 44
	female	2-4 months	32 — 44
	male	4-6 months	31 — 41
	female	4-6 months	31 — 41
	male	6-9 months	32 — 40
	female	6-9 months	32 — 40
	male	9-12 months	33 — 41
	female	9-12 months	33 — 41
	male	1-3 years	32 — 40
	female	1-3 years	32 — 40
	male	3-6 years	32 — 42
	female	3-6 years	32 — 42
	male	6-9 years	33 — 41
	female	6-9 years	33 — 41
	male	9-12 years	34 — 43
	female	9-12 years	34 — 43
	male	12-15 years	35 — 45
	female	12-15 years	34 — 44
	male	15-18 years old	37 — 48
	female	15-18 years old	34 — 44
	male	18-45 years old	39 — 49
	female	18-45 years old	35 — 45
	male	45-65 years	39 — 50
	female	45-65 years	35 — 47
	male	More than 65 years	37 — 51
	female	More than 65 years	35 — 47
Mean erythrocyte volume (MCV), fL	female	0-12 months	71 — 112
	male	0-12 months	71 — 112
	female	1-5 years	73 — 85
	male	1-5 years	73 — 85
	female	5-10 years	75 — 87
	male	5-10 years	75 — 87
	female	10-12 years	76 — 94
	male	10-12 years	76 — 94
	female	12-15 years	73 — 95
	female	15-18 years old	78 — 98
	female	18-45 years old	81 — 100
	female	45-65 years	81 — 101
	female	More than 65 years	81 — 102
	male	12-15 years	77 — 94
	male	15-18 years old	79 — 95
	male	18-45 years old	80 — 99
	male	45-65 years	81 — 101
	male	More than 65 years	81 — 102
Avg. sod. hemoglobin in er-te (MCH), pg	female	0-14 days	30 — 37
	male	0-14 days	30 — 37
	female	14-30 days	29 — 36
	male	14-30 days	29 — 36
	female	1-2 months	27 — 34
	male	1-2 months	27 — 34
	female	2-4 months	25 — 32
	male	2-4 months	25 — 32
	female	4-6 months	24 — 30
	male	4-6 months	24 — 30
	female	6-9 months	25 — 30
	male	6-9 months	25 — 30
	female	9 months — 1 g.	24 — 30
	male	9 months — 1 g.	24 — 30
	female	1-3 years	22 — 30
	male	1-3 years	22 — 30
	female	3-6 years	25 — 31
	male	3-6 years	25 — 31
	female	6-9 years	25 — 31
	male	6-9 years	25 — 31
	female	9-15 years	26 — 32
	male	9-15 years	26 — 32
	female	15-18 years old	26 — 34
	male	15-18 years old	27 — 32
	female	18-45 years old	27 — 34
	male	18-45 years old	27 — 34
	female	45-65 years	27 — 34
	male	45-65 years	27 — 35
	female	More than 65 years	27 — 35
	male	More than 65 years	27 — 34
Avg. conc. hemoglobin in air (MCHC), g/l		0-1 years	290 — 370
		1-3 years	280 — 380
		3-12 years	280 — 360
		12-19 years old	330 — 340
		More than 19 years	300 — 380
Distribution erith. along V - standard deviation (RDW-SD), fL	37 — 54
Distribution erith. according to V - coefficient. Variance (RDW-CV), %		More than 6 months	11.6 — 14.8
		0-6 months	14.9 — 18.7
	female	0-10 days	99 — 421
	male	0-10 days	99 — 421
	female	10-30 days	150 — 400
	male	10-30 days	150 — 400
	female	1-6 months	180 — 400
	male	1-6 months	180 — 400
	female	6 months — 1 g.	160 — 390
	male	6 months — 1 g.	160 — 390
	female	1-5 years	150 — 400
	male	1-5 years	150 — 400
	female	5-10 years	180 — 450
	male	5-10 years	180 — 450
	female	10-15 years	150 — 450
	male	10-15 years	150 — 400
	female	More than 15 years	150 — 400
	male	More than 15 years	150 — 400
Distribution platelet count by volume (PDW), fL	10 — 20
Mean platelet volume (MPV), fL	9.4 — 12.4
Large platelet ratio (P-LCR), %	13 — 43
Neutrophils (NE), 10^9/l		0-4 years	1.5 — 8.5
		4-8 years	1.5 — 8.0
		8-16 years	1.8 — 8.0
		More than 16 years	1.8 — 7.7
Lymphocytes (LY), *10^9/l		0-1 years	2.0 — 11.0
		1-2 years	3.0 — 9.5
		2-4 years	2.0 — 8.0
		4-6 years	1.5 — 7.0
		6-8 years	1.5 — 6.8
		8-10 years	1.5 — 6.5
		10-16 years	1.2 — 5.2
		More than 16 years	1.0 — 4.8
Monocytes (MO), *10^9/l		0-1 years	0.05 — 1.1
		1-2 years	0.05 — 0.6
		2-4 years	0.05 — 0.5
		4-16 years	0.05 — 0.4
		More than 16 years	0.05 — 0.82
Eosinophils (EO), *10^9/l		0-1 years	0.05 — 0.4
		1-6 years	0.02 — 0.3
		More than 6 years	0.02 — 0.5
Basophils (BA), *10^9/l	0 — 0.08
Neutrophils, % (NE%), *10^9/l		0-1 years	16 — 45
		1-2 years	28 — 48
		2-4 years	32 — 55
		4-6 years	32 — 58
		6-8 years	38 — 60
		8-10 years	41 — 60
		10-16 years	43 — 60
		More than 16 years	47 — 72
Lymphocytes, % (LY%)		0-1 years	45 — 75
		1-2 years	37 — 60
		2-4 years	33 — 55
		4-6 years	33 — 50
		6-8 years	30 — 50
		8-10 years	30 — 46
		10-16 years	30 — 45
		More than 16 years	19 — 37
Monocytes, % (MO%)		0-1 years	4 — 10
		1-2 years	3 — 10
		More than 2 years	3 — 12
Eosinophils, % (EO%)		0-1 years	1 — 6
		1-2 years	1 — 7
		2-4 years	1 — 6
		More than 4 years	1 — 5
Basophils,% (BA%)	female	0 — 1.2
Basophils,% (BA%)	male	0 — 1.2
Neutrophils, 10^9/l		0-4 years	1.5 — 8.5
		4-8 years	1.5 — 8.0
		8-16 years	1.8 — 8.0
		More than 16 years	1.8 — 7.7
Lymphocytes, *10^9/l		0-1 years	2.0 — 11.0
		1-2 years	3.0 — 9.5
		2-4 years	2.0 — 8.0
		4-6 years	1.5 — 7.0
		6-8 years	1.5 — 6.8
		8-10 years	1.5 — 6.5
		10-16 years	1.2 — 5.2
		More than 16 years	1.0 — 4.8
Monocytes, *10^9/l		0-1 years	0.05 — 1.1
		1-2 years	0.05 — 0.6
		2-4 years	0.05 — 0.5
		4-16 years	0.05 — 0.4
		More than 16 years	0.05 — 0.82
Eosinophils, *10^9/l		0-1 years	0.05 — 0.4
		1-6 years	0.02 — 0.3
		More than 6 years	0.02 — 0.5
Basophils, *10^9/l	0 — 0.08
Neutrophils: rods. (%)	0 — 5
Neutrophils: segment. (SEG%)		0-1 years	16 — 45
		1-2 years	28 — 48
		2-5 years	32 — 55
		5-7 years	38 — 58
		7-8 years	41 — 60
		8-12 years	43 — 60
		12-16 years old	45 — 60
		More than 16 years	47 — 72
Lymphocytes, % (LY%)		0-1 years	45 — 75
		1-2 years	37 — 60
		2-4 years	33 — 55
		4-6 years	33 — 50
		6-8 years	30 — 50
		8-10 years	30 — 46
		10-16 years	30 — 45
		More than 16 years	19 — 37
Monocytes, % (MO%)		0-1 years	4.0 — 10
		1-2 years	3.0 — 10
		More than 2 years	3.0 — 12
Eosinophils, % (EO%)		0-1 years	1 — 6
		1-2 years	1 — 7
		2-4 years	1 — 6
		More than 4 years	1 — 5
Basophils,% (BA%)	female	0 — 1
Basophils,% (BA%)	male	0 — 1

Interpretation of the analysis:

Anemia

A decrease in hemoglobin and/or red blood cells indicates the presence of anemia. Using the MCV indicator, you can perform a primary differential diagnosis of anemia:

MCV less than 80 fl (microcytic anemia). Causes: iron deficiency anemia;
thalassemia;
anemia of chronic disease;
sideroblastic anemia.

Considering that the most common cause of microcytic anemia is iron deficiency, when identifying microcytic anemia, it is recommended to determine the concentration of ferritin, as well as serum iron and total serum iron-binding capacity. It is recommended to pay attention to the RDW indicator (increased only in iron deficiency anemia) and platelet count (often increased in iron deficiency anemia).

MCV 80-100 fl (normocytic anemia). Causes:
anemia in chronic renal failure - chronic renal failure;
hemolysis;
anemia due to iron or vitamin B12 deficiency.

To exclude hidden bleeding, a stool test for occult blood is recommended. To exclude iron or vitamin B12 deficiency as a cause of normocytic anemia, determine iron and vitamin B12 in the blood. To exclude chronic renal failure, tests for creatinine and blood urea are performed. To exclude hemolytic anemia - tests for haptoglobin, LDH, indirect bilirubin and reticulocytes.

MCV more than 100 fl (macrocytic anemia). Causes:
medications (hydroxyurea, zidovudine);
deficiency of vitamin B12 and folic acid.

Marked macrocytosis (MCV greater than 110 fl) usually indicates a primary bone marrow disease.

To exclude vitamin B12 deficiency as a cause of macrocytic anemia, homocysteine and vitamin B12 tests are performed.

Thrombocytopenia

Causes:

thrombocytopenic purpura/hemolytic-uremic syndrome;
DIC syndrome (disseminated intravascular coagulation);
drug thrombocytopenia (co-trimoxazole, procainamide, thiazide diuretics, heparin);
hypersplenism;
idiopathic thrombocytopenic purpura.

For the differential diagnosis of diseases occurring with thrombocytopenia, a coagulogram, an analysis for HIV infection, antinuclear antibodies and blood protein electrophoresis may also be required.

It should be remembered that in pregnant women, platelets can normally decrease to 75-150×109/l.

Leukopenia

For the differential diagnosis of leukopenia, both the absolute number of each of the 5 main lineages of leukocytes and their percentage (leukocyte formula) are important.

Neutropenia. A decrease in neutrophils of less than 0.5 × 109/l is severe neutropenia. Causes:

congenital agranulocytosis (Kostmann syndrome);
drug neutropenia (carbamazepine, penicillins, clozapine and others);
infections (sepsis, viral infection);
autoimmune neutropenia (SLE, Felty's syndrome).

Lymphopenia. Causes:

tuberculosis.
chronic renal failure;
autoimmune lymphopenia (SLE, rheumatoid arthritis, sarcoidosis);
viral infection (HIV);
drug-induced lymphopenia (glucocorticosteroids, monoclonal antibodies);
acquired variable immunodeficiency;
congenital lymphopenia (Bruton agammaglobulinemia, severe combined immunodeficiency, DiGeorge syndrome);

Polycythemia

Increase in Hb and/or Ht concentration and/or red blood cell count:

polycythemia vera is a myeloproliferative disease; in the blood test, in addition to erythrocytosis, thrombocytosis and leukocytosis are observed;
relative polycythemia (bone marrow compensatory response to hypoxia in COPD or ischemic heart disease; excess erythropoietin in renal cell carcinoma).

For the differential diagnosis of polycythemia, a study of erythropoietin levels is recommended.

Thrombocytosis

Causes:

primary thrombocytosis (malignant disease of the myeloid lineage of the bone marrow, including essential thrombocytosis and chronic myeloid leukemia);
secondary thrombocytosis after removal of the spleen, during an infectious process, iron deficiency anemia, hemolysis, trauma and malignant diseases (reactive thrombocytosis).

An increase in Hb, MCV, or total leukocyte count suggests primary thrombocytosis. The degree of thrombocytosis, as a rule, does not allow differential diagnosis of primary and secondary thrombocytosis, since even a very significant increase in platelets (more than 1000 × 109 l) can also be observed with reactive thrombocytosis. Additional tests may also be recommended: blood ferritin and C-reactive protein.

Leukocytosis

The first step in interpreting leukocytosis is to evaluate the leukocyte count. Leukocytosis can be caused by an excess of immature leukocytes (blasts) in acute leukemia or mature, differentiated leukocytes (granulocytosis, monocytosis, lymphocytosis).

Granulocytosis - neutrophilia. Causes:

leukemoid reaction (reactive neutrophilia in the presence of infection, inflammation, use of certain medications);
myeloproliferative disease (eg, chronic myelogenous leukemia).

An increase in the percentage of band neutrophils of more than 6% indicates the presence of infection, but can also be observed in chronic myeloid leukemia and other myeloproliferative diseases.

Granulocytosis - eosinophilia. Causes:

primary eosinophilia (hypereosinophilic myeloproliferative syndrome);
secondary eosinophilia (parasitosis, helminthiasis, allergies, vasculitis, lymphoma).

Additional tests will depend on your medical history, but should at a minimum include a stool test for helminth eggs.

Granulocytosis - basophilia. Causes:

chronic basophilic leukemia.

Monocytosis. Causes:

myeloproliferative disease, such as CML;
reactive monocytosis (chronic infections, granulomatous inflammation, radiation therapy, lymphoma).

Lymphocytosis. Causes:

reactive lymphocytosis (viral infection); Virus-specific laboratory tests are recommended;
lymphocytic leukemia (acute and chronic).

A clinical blood test with a leukocyte formula is a screening method that can be used to preliminarily assess the state of bone marrow function and suspect or exclude many diseases. This analysis, however, does not always make it possible to establish the cause of the changes, the identification of which, as a rule, requires additional laboratory tests, including pathomorphological and histochemical studies. The most accurate information can be obtained by dynamic monitoring of changes in blood parameters.