Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 13-09: Hemolytic Anemias + Key Features Download Section PDF Listen +++ ++ Generally classified according to whether the defect is intrinsic or extrinsic to the red blood cell (RBC) Intrinsic defects have been described in all components of the red blood cell, including the membrane, enzyme systems, and hemoglobin; most of these disorders are hereditary External factors are immune and microangiopathic hemolytic anemias and infections of red blood cells + Clinical Findings Download Section PDF Listen +++ ++ Symptoms of anemia Jaundice, pigment gallstones, cholecystitis in chronic cases Palpable spleen + Diagnosis Download Section PDF Listen +++ ++ Serum haptoglobin may be low but is neither specific nor sensitive Reticulocytosis present unless second disorder (infection, folate deficiency) superimposed on hemolysis Transient hemoglobinemia occurs with intravascular hemolysis Hemoglobinuria occurs when capacity for reabsorption of hemoglobin by renal tubular cells exceeded Positive urine hemosiderin test indicates prior intravascular hemolysis Hemoglobinemia and methemalbuminemia occur with severe intravascular hemolysis Indirect bilirubin elevated, total bilirubin elevated to ≤ 4 mg/dL; higher bilirubin elevations may indicate hepatic dysfunction Serum lactate dehydrogenase is elevated in microangiopathic hemolysis; may be elevated in other hemolytic anemias + Treatment Download Section PDF Listen +++ ++ See Treatment of specific anemias Folic acid, 1 mg orally once daily Transfusions possible