Congenital dyserythropoietic anaemia type III: an electron microscopic study.

The morphological features of erythroblasts in congenital dyserthropoietic anaemia (CDA) type III were studied by electron microscopy. Typical findings included clefts and blebs within the nuclear region, autolytic areas within cytoplasm, iron-filled mitochondria and myelin figures. The findings resembled those reported in other dyserythropoietic anaemias particularly in CDA type I; the main morphologic features which distinguished the two types were lack of spongy appearance of the chromatin, lack of cytoplasmic organelles within the nuclear region and intact nuclear envelope in CDA type III.