Hereditary RBC membrane disorders

• Hereditary spherocytosis

  • Most frequent; due to decreased RBC deformability due to abnormalities of the cytoskeletal protein spectrin (and/or ankyrin)

  • AD inheritance in 75% of cases; AR inheritance associated with more severe disease (may come from a spontaneous mutation, so don’t rely on family history)

  • C/S: jaundice, splenomegaly, pigment gallstone formation, and mild to moderate chronic hemolysis which may be worsened by infection, resulting in a hemolytic or aplastic crisis

  • May be confirmed with an osmotic fragility test (lysis in hypotonic saline), but this is not specific…the diagnosis is one of exclusion

  • Splenectomy may be beneficial if hemolysis is severe

• Hereditary elliptocytosis – similar to spherocytosis and is also due to an abnormal RBC structural protein

Category: Medical Subject Notes , Pathology Notes