A hemogram – an automatic analysis of blood cells – with a leukogram (white blood cell count) is a complex analysis that measures haemoglobin concentration in the blood, and counts and describes the blood cells: erythrocytes, leukocytes and thrombocytes.
A hemogram contains the following parameters:
Erythrocytes and haemoglobin
Erythrocytes, or red blood cells, contain haemoglobin and provide the body with oxygen. Haemoglobin is a protein compound that contains iron and gives the blood its red colour. Its task is to transport oxygen from the lungs to tissues.
High levels of erythrocytes and/or haemoglobin are found in the blood of smokers, those who have been in low oxygen conditions for long periods of time (e.g., in high altitudes), and where one has lung, heart and certain blood disorders.
Low levels of erythrocytes and/or haemoglobin occur in anaemias of various causes.
Haematocrit
Haematocrit expresses the ratio of the volume of blood cells to the total volume of blood plasma and characterises the viscosity of the blood. It allows for an indirect assessment of fluid balance in the body. The haematocrit values are primarily influenced by the number of erythrocytes and haemoglobin levels but they also depend on the volume of blood plasma, which in turn is affected by the body’s fluid balance.
High haematocrit values occur in conditions that cause an increase in erythrocytes and haemoglobin levels and in case of severe dehydration.
Low haematocrit values occur in anaemia.
Leukocytes
Leukocytes, or white blood cells, are the body’s defence cells. There are five types of such cells circulating in the blood: neutrophils, eosinophils, basophils, monocytes and lymphocytes. The leukogram shows how many different leukocytes circulate in the blood. Each specific leukocyte has a specific role to play in the body’s defence mechanism.
The number of leukocytes and the result of the leukogram make it possible to assess whether the body has any ongoing inflammations or infections (viral, bacterial), allergies; whether it is an acute process or is already in the healing phase. A disruption in the number and relationship of leukocytes indicates a possible blood disorder.
Higher leukocyte counts are more common after bacterial inflammations and infections, as well as after eating, physical exercise and severe stress.
Leukocyte depletion mainly occurs in viral infections.
Thrombocytes
Thrombocytes (platelets) are involved in blood clotting.
Elevated platelet (thrombocyte) counts are associated with leukocyte changes in bacterial infections, iron deficiency or posthaemorrhagic anaemia.
Low platelet (thrombocyte) counts can be caused by viral infections, the use of certain medications, alcoholism, vitamin B12 and folate deficiency, and liver and autoimmune diseases, among other causes.

CRP (C-reactive protein) is a protein that allows to assess the presence and activity of an inflammatory process in the body. CRP is produced by the liver in the acute phase of inflammation. Its concentration changes very rapidly in the blood in response to inflammation.
Along with the assessment of lipids (cholesterols, triglycerides), the risk of cardiovascular diseases and the presence of inflammation in the wall of a calcified blood vessel can be determined.
CRP levels greater than 10 mg/L indicate an inflammatory process in the body.
Reference values (cardiovascular risk assessment):
CRP (mg/L) Risk
<1 Low 1-3 Moderate >3 High
>5 Refers to an inflammatory process. Inflammatory or infectious diseases must be ruled out.

Ferritin is found in the cells of the liver, spleen and bone marrow and reflects the body’s iron stores. The body requires iron to synthesise haemoglobin and ensure the transport of oxygen to the tissues, to regulate cell growth and development, and for heart, muscle and nerve tissue function.
Ferritin levels in the blood decrease in the early stages of iron deficiency. The recommended range for ferritin in the blood serum is >50 ug/l.
Ferritin is also a so-called acute phase protein; its levels in the blood increase during inflammation. In this case, the normal or increased concentration of ferritin does not accurately reflect the body’s iron stores, and this should be taken into account when interpreting the results. Additional tests for iron deficiency can also be performed in anaemic patients with inflammation.
Low levels of ferritin indicate iron deficiency, which may include symptoms such as excessive fatigue, weakness, dizziness, general feeling of weakness, decreased ability to combat colds, decreased muscular capacity and performance, memory impairment, learning difficulties, fear of cold, pale skin, brittle hair and nails, and pale complexion. Together with changes in erythrocytes and haemoglobin, low ferritin levels indicate the possibility and cause of anaemia.
High ferritin levels indicate excess iron in the body, which results in deposition syndromes, triggering allergies, liver and pancreatic damage, joint pain and other conditions.

Alanine aminotransferase is an enzyme that is mostly found in liver cells and to a lesser extent in cardiac and skeletal muscle cells, kidney tissue and elsewhere in the body. When liver cells are damaged, the activity of this enzyme in the blood increases.
High ALAT levels in the blood are due to liver disease.
Moderate increases in ALAT levels in the blood may be due to liver cell damage with a variety of causes: e.g., the use of certain medicines, obesity, alcoholism and muscle damage.

Gamma-glutamyl transferase GGT is an enzyme that regulates the transport of amino acids into cells. It is found in kidney tissue, liver, pancreas, intestines and elsewhere in the body. Serum GGT is predominantly derived from the liver and bile ducts. GGT is naturally higher in men than in women.
GGT levels are affected by persistent alcohol abuse and some medications.
Elevated GGT levels occur in liver and biliary tract diseases, as well as in case of obesity, infectious mononucleosis, hyperthyroidism and diabetes. Elevated GGT levels may also occur in pancreatitis, liver and pancreatic tumours. An increase in GGT also indicates prolonged alcohol abuse.

Creatinine is a by-product of muscle metabolism and is mainly excreted by the kidneys. The level of creatinine in the blood depends on its production, i.e., the person’s muscle mass and physical activity, and the ability of the kidneys to clear the blood of waste products. The more intense the muscle work, the more creatinine is produced. Because creatinine is produced in a relatively constant amount during normal physical activity, its concentration in the blood depends on kidney function.
To assess renal clearance, the estimated Glomerular Filtration Rate (eGFR) is calculated from creatinine in individuals over 18 years of age. The CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formula is used, which expresses the glomerular filtration rate in mL/min /1.73 m2 per standard body surface area. This formula does not take into account the body mass of a particular person, but it does take into account his age, gender and race. As renal function decreases, creatinine accumulates and the eGFR value decreases. eGFR values may decrease from the age of 40 onwards without any indication of renal impairment.
High levels of creatinine indicate high muscle mass, intense physical activity and decreased renal function. It is important to know that eating large amounts of meat up to 7 hours before giving blood can increase creatinine values by about 10%.
Low levels of creatinine are due to prolonged starvation, muscle atrophy or loss of muscle mass, and a lack of physical activity.

Creatinine is a by-product of muscle metabolism and is mainly excreted by the kidneys. The level of creatinine in the blood depends on its production, i.e., the person’s muscle mass and physical activity, and the ability of the kidneys to clear the blood of waste products. The more intense the muscle work, the more creatinine is produced. Because creatinine is produced in a relatively constant amount during normal physical activity, its concentration in the blood depends on kidney function.
To assess renal clearance, the estimated Glomerular Filtration Rate (eGFR) is calculated from creatinine in individuals over 18 years of age. The CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formula is used, which expresses the glomerular filtration rate in mL/min /1.73 m2 per standard body surface area. This formula does not take into account the body mass of a particular person, but it does take into account his age, gender and race. As renal function decreases, creatinine accumulates and the eGFR value decreases. eGFR values may decrease from the age of 40 onwards without any indication of renal impairment.
High levels of creatinine indicate high muscle mass, intense physical activity and decreased renal function. It is important to know that eating large amounts of meat up to 7 hours before giving blood can increase creatinine values by about 10%.
Low levels of creatinine are due to prolonged starvation, muscle atrophy or loss of muscle mass, and a lack of physical activity.

Glucose or blood sugar is the body’s main source of energy. Blood glucose is kept stable in the body. After a meal, its levels return to baseline within 2-4 hours. When there is a need for more energy, the body produces glucose from proteins or lipids.
High glucose levels indicate a disruption of carbohydrate metabolism and the possibility of diabetes. High levels of exercise, stress, burns and infections can also cause the blood sugar levels to rise.
Low glucose levels can occur if the amount of carbohydrates in the diet is not enough for physical exercise.

Glycated haemoglobin is the part of haemoglobin that is associated with glucose in the blood. It shows the average blood glucose level within 6-8 weeks before sampling. The analysis helps to monitor the progression of the disease in individuals with both type 1 and type 2 diabetes. In addition, glycated haemoglobin helps to assess the risk of developing diabetes. The result is given as both concentration and percentage.
Elevated glycated haemoglobin values indicate an increased risk of diabetes or already established diabetes.
Low glycated haemoglobin values indicate hypoglycaemia, which is an abnormal level of blood sugar and is a condition that leads to a reduction in the lifespan of erythrocytes (haemolytic anaemia, recent or chronic blood loss, pregnancy in women).

Glycated haemoglobin is the part of haemoglobin that is associated with glucose in the blood. It shows the average blood glucose level within 6-8 weeks before sampling. The analysis helps to monitor the progression of the disease in individuals with both type 1 and type 2 diabetes. In addition, glycated haemoglobin helps to assess the risk of developing diabetes. The result is given as both concentration and percentage.
Elevated glycated haemoglobin values indicate an increased risk of diabetes or already established diabetes.
Low glycated haemoglobin values indicate hypoglycaemia, which is an abnormal level of blood sugar and is a condition that leads to a reduction in the lifespan of erythrocytes (haemolytic anaemia, recent or chronic blood loss, pregnancy in women).

High cholesterol level is one of the biggest health risks in Estonia and worldwide. Therefore, every adult person should know and monitor their blood cholesterol levels, especially from the age of 30.
Cholesterol is an indispensable and vital component of the body. It is a building block of cell membranes and a precursor for the production of many hormones and vitamin D. Cholesterol is derived from animal feed, synthesised by the liver and excreted in the bile. Cholesterol levels are largely affected by diet.
Cholesterol is present in the blood in lipoproteins: chylomicrons, VLDL, IDL, LDL and HDL lipoproteins. Cholesterol test determines the total amount of cholesterol in different lipoproteins.
Increased cholesterol levels in the blood cause atherosclerosis and are among the main risk factors for cardiovascular diseases. Higher than recommended cholesterol levels can be caused by a high-fat and cholesterol-rich diet, biliary obstruction, decreased renal function, hypothyroidism, diabetes, obesity and familial hypercholesterolemia.
Decreased cholesterol levels may occur as a result of the consumption of vegetable fats, malnutrition or malabsorption, liver disease and hyperthyroidism.

LDL cholesterol (low-density lipoprotein) is responsible for transporting cholesterol to tissues. LDL is known as ‘bad cholesterol’ because its high levels in the blood cause atherosclerotic changes in the medium- and small-diameter arteries, disturbing the blood supply to various organs. Atherosclerosis of the coronary arteries that supply blood to the heart can cause angina (chest pain) or heart attack, or stroke if the blood vessels in the brain are damaged.
Elevated LDL-cholesterol levels are an important risk factor for cardiovascular diseases. LDL levels may increase in the case of diabetes, hypothyroidism and decreased renal function.

HDL cholesterol (high-density lipoprotein) is responsible for transporting cholesterol back from the tissues to the liver. It is known as ‘good cholesterol’ because it helps remove excess cholesterol from the blood, thereby reducing the risk of atherosclerosis.
Low levels of HDL cholesterol are a major risk factor for cardiovascular diseases. This can be due to acute illness, trauma, diabetes, liver disease, anaemia, hypothyroidism or renal impairment.

Triglycerides are an important source of energy for the body. The body makes triglycerides from edible fats, but they are also formed in the liver and adipose tissue. Triglycerides are deposited and stored in the adipose tissue. To determine triglycerides levels, it is important to fast for 10-14 hours before giving blood.
Elevated triglyceride levels indicate impaired lipid metabolism and are an important risk factor for cardiovascular diseases. The level of triglycerides in blood may increase in case of obesity, diabetes, hypothyroidism, alcoholism, pancreatitis and chronic liver or kidney disease.

Uric acid is the end product of purine metabolism. Purines are natural organic substances containing nitrogen. They are vital for the production of DNA, RNA and various enzymes. Purines are obtained from food (meat, fatty fish, seafood, peas, beans, beer), while the formation and deposition of uric acid is promoted by alcohol consumption and water loss.
Uric acid is found in all tissues of the human body, but its accumulation can be caused by genetic predisposition, the consumption of foods rich in uric acid and alcohol, as well as some medications. Uric acid is an important antioxidant.
In case of high levels of uric acid in the blood, it begins to deposit in the tissues as crystals. Such crystals can form in joints, cartilage, tendons, kidneys and other parts of the body, causing acute inflammation. When inflammation occurs in the joint of the big toe, it is called gout. Men and older women are most at risk. The high levels of uric acid in the urine can lead to the development of kidney stones.
Elevated levels of uric acid may indicate a risk of gout and kidney stones, rapid severe weight loss or tissue damage.

Thyroid-stimulating hormone (TSH) regulates the synthesis and release of thyroid hormones. Thyroid hormones (T3 and T4) are involved in the regulation of the body’s metabolism. The hormone test is applicable in screening for thyroid diseases. Thyroid disease is more common in women. In men, the clinical picture of the disease is much more hidden.
High TSH values indicate hypothyroidism and the decreased production of thyroid hormones. In hypothyroidism, the body’s metabolism is slower than normal. Symptoms include weight gain, constipation, chronic fatigue and apathy, slow heart rate, high cholesterol, cold intolerance, hair loss and dry skin.
Low TSH values indicate hyperthyroidism and the overproduction of thyroid hormones. In hyperthyroidism, the body’s metabolism is accelerated. Symptoms include weight loss, heart palpitation, irritability (readiness to cry), hand tremors, intolerance to heat (e.g., sauna), constant sweating unrelated to physical exercise, and photosensitive and enlarged, slightly swollen eyes.

Vitamin B12 (cobalamin) is a cobalt-containing water-soluble vitamin, which plays an important role in the synthesis of nucleic acids, amino acids, proteins and myelin (the insulating membrane surrounding nerve cells). It is required for the synthesis of haemoglobin in the bone marrow and for normal neurological function.
The vitamin is found only in animal-source foods, but its absorption is inhibited by atrophic gastritis and other diseases of the gastrointestinal tract, excessive consumption of alcohol and coffee, smoking, oral contraceptives, and laxatives. The absorption of vitamin B12 often decreases with age.
Vitamin B12 deficiency can be caused by low food intake of vitamin B12 (vegetarians), gastrointestinal diseases, changes in the intestinal microflora, broad tapeworm infection and other factors.
Chronic vitamin deficiency causes anaemia and various types of nerve damage.

Folate is a water-soluble B-group vitamin (B9), which, together with vitamin B12, is vital for the normal metabolism of proteins, fats and carbohydrates, cell regeneration and damage prevention. It is also involved in DNA synthesis and repair. Folate deficiency primarily affects rapidly proliferating tissues – haematopoiesis, mucous membranes, skin and bone tissue. It is also important in ensuring the quality and quantity of sperm. Folate is also involved in reducing the risk of cardiovascular diseases by lowering homocysteine levels in the blood.
Folate can be obtained only through food, as the body does not produce it itself. Folate is heat sensitive and decomposes quickly during cooking. The absorption of folic acid is reduced by smoking, alcohol, coffee, some medicines and concomitant chronic diseases.
The manifestation of folate deficiency is the development of anaemia, which can be accompanied by neurological, mental and sensitivity disorders. Furthermore, in childhood and during puberty, folate deficiency can affect the normal development of the body, inhibiting growth. Lower sperm counts have been observed in men with low folate levels.

Vitamin D is a fat-soluble steroid hormone. There are two main forms of vitamin D: D2 and D3.
Vitamin D2 is not synthesised by the body; instead, it is obtained from food (plants and some mushrooms).
Vitamin D3 is of animal origin (mainly fish), but the largest portion of vitamin D3 is synthesised in the skin upon exposure to ultraviolet light. Ultraviolet B (UVB) radiation in summer around midday on the hands and face for 10-15 minutes results in the synthesis of 800-1000 units of previtamin D3 in the skin, which is enough to cover the daily needs of an adult person.
The circulating metabolite 25 (OH) of vitamin D, or calcidiol, is measured in the blood and is the best indicator of vitamin D supply in the body.
Vitamin D affects calcium metabolism, blood clotting, nervous tissue function, strengthens the immune system and heart, and lowers blood sugar levels and blood pressure. The role of this vitamin in muscle work is to help maintain balance and support coordination.
Low levels of vitamin D interfere with the intestinal absorption of calcium and phosphates, which increases the risk of osteoporosis (bone loss).
There is an association between vitamin D deficiency (< 50 nmol/l) and the incidence of viral diseases, multiple sclerosis, hypertension, rheumatoid arthritis, diabetes and other autoimmune diseases.

The prostate-specific antigen PSA is a glycoprotein produced only in the prostate. Its production is regulated by male hormones. In a normal prostate, PSA levels depend on its size, and as the gland enlarges, more PSA is produced. PSA tests are used for the early detection of prostate cancer and to evaluate the effectiveness of treatment. In case of prostate cancer, the increase in PSA levels is rapid, while in case of benign processes it is slower.
PSA levels in the blood are normally very low, but increase in case of benign prostatic hyperplasia and inflammation, and especially in prostate cancer. PSA levels are highly affected by factors that irritate prostate (ejaculation, prostate massage, prolonged cycling), which must be taken into account when giving a blood test. PSA levels in the blood also increase with age, so normal values are age-specific.

In men, testosterone is the main male hormone produced in the testicles. Most of the circulating testosterone is bound to proteins, and only 1-3% of the hormone is in free or active form. Testosterone is one of the most important regulators in the male body: its receptors are present in many different cells, which means that this male hormone is involved in the functioning of most cells.
Testosterone affects sperm development, prostate function, development of potency and secondary sex characteristics (e.g., beard, moustache, more developed musculature, taller height, etc.), as well as muscle mass and performance.
Low testosterone levels in men occur due to hypogonadism (gonads not working normally), alcoholism, smoking, obesity, intense physical exercise, certain medications or oestrogen therapy. With age, testosterone levels also tend to decrease.
High testosterone levels occur in adrenal and testicular tumours as well as in hyperthyroidism. Artificially, testosterone levels can be increased with anabolic steroids, which are used to stimulate rapid muscle growth.