The Familial Aplastic Crisis in Hereditary Spherocytosis. Urocanic Acid and Formiminoglutamic Acid Excretion Studies in a Case with Megaloblastic Arrest

A case of herditary spherocytosis who presented with an aregenerative crisis is reported. Evidence of megaloblastic hemopoiesis was present and was accompanied by the urinary excretion of large amounts of urocanic acid following oral dose of histidine hydrochloride. The severe illness in this patient was accompanied by a reticulocytopenia in a younger sister who, however, remained well clinically.