All are features of Intravasular hemolysis except ?
Ans. is 'a' i.e., Thrombocytopenia Hemolytic anemia o Hemolytic anemia is anemia due to hemolysis, i.e. the abnormal breakdown of red blood cells. o Hemolytic anemia has the following features ? 1.A shoened red cell life span, i.e. premature destruction of red cells. 2.Elevated erythropoietin level and inceased erythropoiesis in the marrow and other sites, to compensate the loss of red cells --> characterized by increased reticulocyte count. 3. Accumulation of the products of hemoglobin catabolism due to an increased rate of red cell destruction. o Hemolysis may occur either inside the blood vessels (intravascular hemolysis) or within the mononuclear phagocytic system of spleen, liver or bone marrow (extravascular hemolysis). Intravascular hemolysis o Due to destruction of RBC, hemoglobin is released into blood --> Hemoglobinemia. o Excess of hemoglobin may be excreted by kidney --> hemoglobinuria. Some of the hemoglobin is reabsorbed in kidney and is conveed to hemosiderin which is then excreted --> hemosiderinuria. o Free hemoglobin in plasma bound to haptoglobin and this complex is rapidly cleared by mononuclear phagocytic system --> Decreased heptoglobin. o When heptoglobin is depleted, free hemoglobin is oxidized to methemoglobin --> methemoglobinemia. Excess heme groups are catabolized to bilirubin within the mononuclear phagocytic system --> Increased indirect bilirubin and jaundice. LDH is stored in the blood. During hemolysis this enzyme is released in the blood Increased serum LDH.
Thrombocytopenia
Hemosiderinuria
Decreased haptoglobin
Raised indirect bilirubin