Atypical hereditary ovalocytosis associated with defective dyserythropoietic anemia.

The cases of a child and his mother affected by chronic anemia with atypical elliptocytosis are reported. When adolescent the mother underwent splenectomy, with an incomplete response. Anemia was characterized by a morphological picture of ovalocytosis associated with a significant percentage of spherocytes in the peripheral blood of the child and spiculated red cells in that of the splenectomized mother. Bone marrow aspirates of the child showed a striking erythropoietic hyperplasia with marked decrease of mature cells and dyserythropoietic features. Reticulocyte count was rather low. Ferrokinetics showed ineffective erythropoiesis. Biochemical studies on red blood cell membrane cytoskeleton showed that beta-spectrin, alpha-spectrin and protein 4.1, which are usually altered in hereditary elliptocytosis (HE), were normal in our cases. This report confirms the hypothesis of Torlontano who postulated the existence of a distinct atypical form of HE associated with ineffective and dysplastic erythropoiesis.