Abstract
A case of acquired primary sideroblastic anemia in a 63-year-old Japanese male was reported.
He was admitted to the Toranomon Hospital in March 1966, because of anemia. Peripheral blood showed moderate normochromic anemia with hypersideremia. Examination of bone marrow revealed normoblastic hyperplasia with partially defective hemoglobin formation. Sideroblasts were markedly increased, over half of them were ringed sideroblasts.
In electron-microscopic study, a large quantity of iron was demonstrated in swollen mitochondria surrounding nucleus of erythroblasts. Although the life-span of the patient's erythrocytes estimated by the radio-chromium method was moderately reduced, neither signs nor laboratory data suggesting a certain type of hemolytic anemias could be obtained.
Erythrocyte coproporphyrin content was normal, and the amount of erythrocyte protoporphyrin exceeded the normal. The results of ALA synthetase, ALA dehydrase and heme synthetase assays in erythroblasts all came out normal.
It was speculated that a disturbance in iron incorporation into heme in erythroblast mitochondria might be responsible for the cause of this type of anemia.
