Two cases of red cell aldolase deficiency associated with hereditary hemolytic anemia in a japanese family

Abstract
Two cases of red cell aldolase deficiency associated with congenital nonspherocytic hemolytic anemia are reported. The proband is a fourteen‐month‐old Japanese boy. Consanguineous marriage was not proven but probable in this family, as the parents were born in the same small island. The proband had moderate to mild anemia aggravated by upper respiratory infections, 1 cm hepatomegaly and 2.5 cm splenomegaly, but was unremarkable in other respects and has thus far not shown mental or growth retardation. He did not have dysmorphic features. The red cell aldolase activity was 6% of the normal mean. The enzyme was unstable with respect to heat, and Km for fructose 1,6‐diphosphate (F‐1,6‐DP) was high. The parents and other heterozygotes showed intermediate activity between that of the proband and that of normal subjects. Red cell F‐1,6‐DP concentration in this case was remarkably increased. Red cell glucose consumption, and lactate formation, as well as hexose monophosphate shunt activity, were decreased as compared with a comparable reticulocyte‐rich hereditary spherocytosis patient. Hexose monophosphate shunt activity was assumed to be decreased due to inhibition of glucose 6‐phosphate dehydrogenase by a high concentration of F‐1,6‐DP in his red cells. As a result of family study, another homozygous aldolase deficiency case associated with hemolytic anemia was found. He is 13 years old and a nephew of the proband's paternal grandmother. His hemolytic anemia also is moderate to mild and aggravated by upper respiratory infections. He does not seem to have mental or growth retardation, nor does he possess dysmorphic features.