[Ultrastructure of erythroid cells in a case of congenital dyserythropoietic anaemia type II (author's transl)].

The ultrastructure of erythroblasts in a case of congenital dyserythropoietic anaemia type II with a negative serum-lysis test is described. The well known symptoms in electronmicroscopy in CDA type I and II are faced to our findings. Morphological changes of hypolemmal cisterns are described and their possible meaning is discussed.