Anemia

Anemia is defined as a decrease in the concentration of hemoglobin in 1 liter of peripheral blood to a value lower than 135 g in men and lower than 120 g in women. A lower hemoglobin value is accompanied by reduced hematocrit (the proportion of hemoglobin relative to total blood volume) and a decreased number of erythrocytes. Oxygen is delivered to tissues after binding to hemoglobin, whose amount is reduced, resulting in tissue hypoxia (lack of oxygen). The few red blood cells present are not able to ensure sufficient oxygen transport to all tissues, to which the body responds with compensatory mechanisms such as shortness of breath, increased heart rate, etc. Despite these mechanisms, certain tissues and organs do not receive adequate oxygenation, and therefore the symptoms of anemia include pallor of the skin and conjunctivae, fatigue, weight loss, failure to thrive, headaches, loss of appetite, palpitations, the already‑mentioned shortness of breath, or collapse. Jaundice accompanies a sudden onset of anemia caused by red blood cell breakdown.

Causes:

• increased blood loss – post‑hemorrhagic (acute bleeding, gastrointestinal bleeding from ulcers or tumors)
• impaired blood formation (iron deficiency, vitamin B12 deficiency, folic acid deficiency, aplastic anemia, myeloblastic anemia, anemia of chronic disease, decreased thyroid function, kidney diseases – reduced production of erythropoietin, bone marrow damage by toxins, radiation, tumors, or fibrosis)
• increased breakdown of erythrocytes (congenital and acquired hemolytic anemias, thalassemia, drug‑induced hemolytic anemia)

Diagnosis:

The diagnosis of anemia can be established only by blood tests, specifically by determining hemoglobin levels, the number and size of red blood cells, and possibly bilirubin levels in cases of red blood cell breakdown. A blood smear is necessary for microscopic evaluation of the shape, size, and density of all blood cell components.

Iron‑deficiency anemia (caused by insufficient intake, impaired absorption, or poor utilization of iron) is diagnosed by measuring serum/blood iron levels. Iron exists in blood in two forms: as bound (functionally used) and as storage iron. Iron is found, for example, in breast milk, certain types of vegetables and fruits, and meat. Iron passes through the intestinal mucosa into the blood and then to blood‑forming organs. A congenital or acquired disorder may occur at any point along this “pathway.” Treatment in this case consists of iron supplementation, sometimes even in injectable form. Anemia may also arise from other deficiencies, such as copper deficiency, folic acid deficiency (medically: megaloblastic anemia), congenital pernicious anemia, anemia due to deficiency of certain B vitamins, and others.

Congenital anemias have their cause in disorders of blood‑forming organs such as the bone marrow; they may be associated with other congenital defects and require complex diagnostic evaluation and treatment. Anemias occurring as accompanying conditions of other underlying diseases are usually associated with immune or hormonal disorders, and their diagnosis and treatment depend on the primary disease. Anemias due to increased blood loss or red blood cell loss may be caused by breakdown triggered by various factors. Exsanguination is caused by external factors such as injury, and symptoms may appear with delay. Red blood cell breakdown may be caused by medications, diseases (e.g., viral and infectious diseases), or toxic substances (e.g., animal poisons). Disorders of red blood cell hemoglobin are often congenital and lead not only to changes in its levels but also in its composition. All types of rare forms require complex diagnostics and therapy.

• slabosť
• poruchy imunity
• porucha hormonálneho riadenia