New variant of congenital dyserythropoietic anemia with trilineage myelodysplasia.

We report the case of a male infant with a variant of congenital dyserythropoietic anemia (CDA), who developed severe hyperbilirubinemia on the day of birth, subsequent severe anemia, and hyperferritinemia. Bone marrow and laboratory examinations revealed features of CDA including trilineage myelodysplasia and erythroblasts with a binucleated nuclear morphology and ineffective erythropoiesis. The CDA in this patient was assumed to be a new variant type because of: the lack of internuclear chromatin bridges in the erythroblasts with abnormal nuclear morphology; a negative acid serum test; the presence of erythrocyte antigen I, and the effect of splenectomy. Trilineage myelodysplasia in CDA is not known. An abnormality in the stem cells was suggested to be the cause of CDA in this case.