1. Red cells from three patients of different families with heteditary elliptocytosis were transfused and their survival followed by the Ashby technic of differential agglutination.
2. Life span of elliptocytes was normal in two cases.
3. A life span of forty-five days was obtained with the elliptocytes of a third patient who presented other evidence of hemolysis in the absence of anemia.
4. In two recipients with sickle cell anemia the survival of the transfused elliptocytes was also followed by counting the number of elliptocytes in sickle cell preparations. Rough agreement between the results of the Ashby and visual technics was obtained. There was no evidence of transformation from the elliptocytic into normal shape.
5. Elliptocytes from patients with hemolytic elliptocytosis were morphologically indistinguishable from elliptocytes with normal life span.
6. No hemoglobin abnormalities have yet been demonstrated in hereditary elliptocytosis. The basic defect responsible for hemolytic elliptocytosis remains unknown.
7. Symptomatic ovalocytosis occurs in many types of anemia, and must be differentiated from hereditary elliptocytosis.
8. The place of hereditary elliptocytosis in the classification of familial hemolytic diseases is discussed (table 4) and similarities to the other hereditary hemotic anemias are pointed out. It is shown that the red cell life span (and genetic) pattern of hereditary elliptocytosis resembles closely that found in thalassemia. As in thalassemia major, microspherocytosis and increased osmotic fragility due to red tell fragmentation may occur in cases of hemolytic elliptocytosis. Increased life span of these "fragmentation-spherocytes" after splenectomy may partially explain the success of the operation in hemolytic elliptocytosis.
9. No treatment is required for hereditary nonhemolytic elliptocytosis. Splenectomy is advised for "decompensated" hemolytic elliptocytosis.