OBJECTIVETo analyze the clinical and laboratory features of patients with congenital dyserythropoietic anemia type I (CDA-I), and improve the clinical diagnostic accuracy.

METHODSThe clinical and hematological features of 5 patients diagnosed as CDA-I in our hospital between July 2002 and July 2007 were analyzed retrospectively, and the related literatures was reviewed.

RESULTSFive CDA-I patients, 1 male and 4 females, all had a long history of varied degree of chronic anemia. One patient had congenital malformations, 3 jaundice and 4 hepatosplenomegaly. Bone marrow specimens invariably showed hypercellularity due to erythroid hyperplasia with megaloblastic changes, irregularly shaped nuclear, and chromatin bridges in 0.2% to 0.6% of all erythroblasts. All the 5 patients' bone marrow erythroblasts showed spongy heterochromatin appearances (swiss-cheese) with electron microscopy examination. There was no morphologic abnormality in the granulocytes and megakaryocytes. Serum ferritin levels were increased in 3/4 patients. One patient had been misdiagnosed as hereditary spherocytosis and performed splenectomy in the local hospital with no improvement in Hb level.

CONCLUSIONSCDA-I is a rare congenital anemia characterized by ineffective erythropoiesis, jaundice, hepatosplenomegaly and iron overload, and may be misdiagnosed. Keeping these manifestations in mind should avoid misdiagnosis.