• A congenital hemolytic anemia caused by defects of the erythrocyte membrane, enzyme deficiencies, or hemoglobinopathies.
  • A familial congenital hemolytic anemia characterized by numerous abnormally shaped erythrocytes which are generally spheroidal. The erythrocytes have increased osmotic fragility and are abnormally permeable to sodium ions.
  • An autosomal dominant inherited disorder characterized by the presence of smaller than normal, sphere-shaped erythrocytes. It results in hemolytic anemia and splenomegaly.
  • Autosomal dominant trait marked by splenomegaly, jaundice, and fragile, spheroid erythrocytes which are prematurely cleared by the spleen; anemia is usually mild; treatment is splenectomy.
  • Hemolytic anemia due to various intrinsic defects of the erythrocyte.
  • Includes hereditary erythrocyte membrane defects, enzyme deficiencies, hemoglobin abnormalities, stem cell defects (paroxysmal nocturnal hemoglobinuria), and alloimmune (rh) disease of newborn.