Symptoms of acute posthemorrhagic anemia consist of two syndromes - collaptoid and anemic, caused by a sharp decrease in the BCC. Signs of the collaptoid syndrome prevail over the anemic one.
Causes of acute posthemorrhagic anemia: Bleeding from the umbilical vessels (trauma to the umbilical cord vessels, lifting the newborn above the level of the placenta with the umbilical cord not clamped); Defective care of the umbilical cord remnant (cutting of the umbilical vessels with a Ragovin clamp, insufficiently tight ligation of the umbilical cord remnant, too vigorous removal of the umbilical cord remnant at the moment of its falling off)
Minor blood loss in older children does not cause significant clinical symptoms and is relatively well tolerated. Significant blood loss is less well tolerated by children than by adults.
Paroxysmal nocturnal hemoglobinuria (Marchiafava-Micheli disease) is a rare form of acquired hemolytic anemia, occurring with a frequency of 1:50,000 in the population.
Hemolytic anemias associated with mechanical damage to the erythrocyte membrane occur in patients with aortic valve prostheses due to intravascular destruction of erythrocytes.
Cases of hemolytic anemia have been described after the bite of bees, scorpions, spiders, snakes (in particular, vipers). Very common and dangerous are poisonings by mushrooms, especially morels, fraught with severe acute hemolysis.
Drug-induced hemolytic anemia develops as a result of exposure to many drugs that cause hemolysis. There are 3 known mechanisms for the development of drug-induced (immune) hemolytic anemia.
Immune hemolytic anemias are a heterogeneous group of diseases in which blood or bone marrow cells are destroyed by antibodies or sensitized lymphocytes directed against their own unmodified antigens.
Transfusion therapy for sickle cell disease is associated with increased blood viscosity until Hb S levels are significantly reduced; hematocrit should not exceed 25-30% before initiating red blood cell transfusion.
The hemogram reveals normochromic hyperregenerative anemia - the hemoglobin concentration is usually 60~80 g/l, the number of reticulocytes is 50-150%. Peripheral blood smears usually contain erythrocytes that have undergone irreversible "sickle formation" - sickle-shaped erythrocytes; aniso- and poikilocytosis, polychromatophilia, ovalocytosis, micro- and macrocytosis are also detected, Cabot rings and Jolly bodies are found.
