[X-linked sideroblastic anemia].

A 20-year-old man presented with microcytic hypochromic anemia (hemoglobin: 9.3 g/dl, MCV: 82.0 fl, MCHC: 29.5 g/dl) and dimorphism RBCs in circulating blood (RDW: 26.8%). Ringed sideroblasts accounted for 29.5% of bone marrow erythroblasts. Iron overload was also observed. Because the patient had a clear family history of anemia, he was given a diagnosis of X-linked sideroblastic anemia. The activity of delta-aminolevulinic acid synthase (ALAS) in bone marrow erythroblasts was low. However, we did not detect mutation of the gene for ALAS. The patient has responded well to a treatment regimen consisting of oral vitamin B6, Fe-chelation therapy, and phlebotomy.