[Hereditary spherocytosis associated with severe hypophosphatemia in patients recovering from aplastic crisis].

This is a report about two cases of hereditary spherocytosis complicated by severe hypophosphatemia, while recovering from aplastic crisis. Case #1: A 31-year-old male, who had jaundice and splenomegaly since the age of 15 and who has a son diagnosed with hemolytic anemia, was admitted because of fever lymphadenopathy, and jaundice. A diagnosis of hereditary spherocytosis was made based on microspherocytes observed in his peripheral blood smear. After admission, the anemia became more serious for a few days and he was considered suffering from bone marrow aplastic crisis. His serum phosphorus level fell to 0.5 mg/dl on the second day, but it rapidly returned to normal as reticulocyte counts rose. Case #2: A 29-year-old male with known transient jaundice and splenomegaly suffered from fever, anemia and jaundice, but recovered two weeks later. Laboratory examination revealed positive human Parvovirus B19 (HPV-B19) DNA, anti-HPV-19 IgM and IgG-antibody. His serum phosphorus level fell to 1.2 mg/dl on the eighth day, but it rose in the same manner as seen in case #1. The fall in serum phosphorus is probably due to its shift to the erythroblasts during erythroid hyperplasia.