Abstract
δ-aminolevulinic acid (ALA) synthetase activity in erythroblasts has been measured by the new method developed in our laboratory in 5 patients with sideroblastic anemia. These patients were admitted in the Tokyo University Hospital, Nagoya University Hospital, Okayama University Hospital, and Toranomon Hospital. Diagnosis of the sideroblastic anemia had been established in these hospitals. The ALA-synthetase activity was markedly reduced to almost deficient level in one case, moderately decreased in 2 cases, and normal in 2 cases. In the case with markedly decreased ALA-synthetase activity, incorporation of 14C-glycine into heme in erythroblasts was also markedly reduced. Decrease in hemesynthetase activity in erythroblasts of this case, however, was slight as compared to the decrease in ALA-synthetase activity. The authors believe that this is the first case of sideroblastic anemia with proven deficiency of ALA-synthetase activity.
