HEMOLYSIS - destruction of red blood cells, accompanied by the release of hemoglobin from them. In this case, blood or a suspension of red blood cells turns into a clear red liquid (lacquer blood). The causes of hemolysis may be abnormalities of the red blood cells themselves or the effects of external factors (serum antibodies, damage to red blood cells, infectious agents). The physical factors causing hemolysis include the action of high and low temperatures, ultrasound, the chemical ones include hemolytic poisons, some drugs, etc. Hemolysis can occur during transfusion of incompatible blood, injections of hypotonic solutions, as a result of hereditary insufficiency of red blood cell enzyme systems, due to the formation of autoantibodies directed against erythrocyte antigens, and when using certain medications (antibiotics, quinine, isoniazid, dopegitis, etc.).
Hemolysis can occur in the blood (intravascular hemolysis) and in organs (intracellular hemolysis). Normally, mainly intracellular hemolysis is observed, while part of the red blood cells is destroyed daily, mainly in the bone marrow and spleen, and the released hemoglobin turns into bilirubin. With increased hemolysis, the formation of bilirubin and its excretion with bile increases, as well as the excretion of urobilin, sterkobilin and other urobilinoids with feces and urine; clinically frequent jaundice and splenomegaly. If a lot of hemoglobin is released during intravascular hemolysis and the haptoglobin system cannot cope with its processing, hemoglobinemia and hemosiderinemia occur, sometimes hemoglobinuria. Intravascular hemolysis may be accompanied by fever, chills, tachycardia, back pain. The immediate consequence of hemolysis is hemolytic anemia, which can be combined with a change in the number of leukocytes, platelets, the formation of blood clots in the vascular bed, and the development of cholelithiasis. A sharp increase in the degree of hemolysis (hemolytic crisis) usually leads to the development of anemia or its deepening.