ABSTRACT
This chapter describes intrinsic red cell abnormalities that affect the red cell membrane and the membrane skeleton. Hereditary spherocytosis (HS) is produced by mutations in the genes encoding several different component proteins of the membrane skeleton. HS ranges in clinical severity from life-threatening neonatal anemia to mild, compensated hemolysis that eludes clinical detection entirely. In the evaluation of all anemia patients, especially those with suspected hemolytic anemia, examination of the peripheral blood smear is of paramount importance. Patients with HS may require red cell transfusions for a plastic crisis, chronic folate administration to ward off megaloblastic crisis, or cholecystectomy for biliary lithiasis. Hereditary elliptocytosis (HE) is a very heterogeneous group of genetic disorders that share the common characteristic of elongated, elliptical erythrocytes. The plethora of mutations and genes involved in HE precludes the routine application of genetic testing to patients with HE.
