New sporadic case of congenital dyserythropoietic anemia type III in an aged woman: detailed description of ultrastructural findings.

We describe a new case of congenital dyserythropoietic anemia (CDA) type III. This least common type of CDA was diagnosed at the age of 59 in a 70-year-old woman who suffered from a young age from mild macrocytic anemia, while the long follow up since diagnosis documented a benign clinical course. No family history of blood diseases was obtained and no anemia was documented in the medical records of any of her four children. The bone marrow (BM) examination on light microscopy revealed a severe erythroid hyperplasia with the presence of giant multinucleated erythroblasts. Ultrastructural examination of the BM disclosed the presence of many large multinucleated erythroblasts bearing a variety of ultrastructural findings: nuclear clefts, autophagic vacuoles, iron-loaded mitochondria, and intracytoplasmic myelin figures. In addition, extensive hyperlobulation of the nucleus and partial loss of nuclear membrane with "spilling" of nuclear material to the adjacent cytoplasm was also noted in some of the erythroblasts. These last two findings have not been previously described in CDA III.