Hereditary spherocytosis is a rare disease amenable to cure. About two in 10,000 persons in the northern part of United States are affected by the hemolytic process, which is usually transmitted by an affected parent to half of his children. The defect, although not completely understood, is manifest in the abnormally rounded erythrocyte (spherocyte) which the spleen traps and destroys preferentially. In most cases the increased rate of cell destruction can be compensated by expansion of the bone marrow, and splenectomy stops hemolysis, although the spherocytes remain.
Hereditary spherocytosis is often unrecognized by the physician and the family. In kinships in which spherocytosis has not been recognized, more than 90% of the affected family members give no history of the condition. If one or more members of the family is known to have the disease, less than half of the remaining affected family members give a positive history. Unless the