Red cell abnormalities in a kindred with an uncommon form of hereditary spherocytosis.

Red cell acetylcholinesterase (AChE) and Na, + K ~adenosinetriphosphatase (ATPase) activities, cell 2,3 diphosphoglycerate (2,3 DPG) and adenosinetriphosphate (ATP) content and filterability ratio were studied in two children (with moderate hemolytic anemia and marked spherocytosis) and their parents. Patients’ parents have no medical problem but evidenced discrete spherocytosis on peripheral smear. Except some increased apparent red cell rigidity detected in the father, all the parameters studied in both parents were found to be normal, as compared to healthy controls. In contrast, red cell rigidity, 2,3-DPG and ATP levels and Na, + K + ATPase activity were increased in both children, whereas AChE activity was similar to values of normal subjects. These observations suggest that both affected patients suffered from homozygous hereditary spherocytosis linked to an apparently recessively inherited red cell membrane defect.