An ultrastructural study of the red pulp of the spleen and the liver in unstable hemoglobin hemolytic anemia.

Electron microscopic observations on the process of red cell destruction in the spleen and liver of a patient with congenital Heinz body hemolytic anemia, associated with a new variant of unstable hemoglobin, are reported. Two major mechanisms of destruction of Heinz body-containing red cells were noted. One was phagocytosis of these cells in toto by cordal macrophages. The other mechanism though less significant quantitatively, was intravascular hemolysis of injured red cells in the splenic microvasculature. In the liver, phagocytosis of damaged red cells by Kupffer cells was rate and there was no evidence of intravascular hemolysis in this organ. These morphological findings, together with almost complete recovery from hemolysis following splenectomy, indicated that Heinz body-containing red cells were removed from the circulation predominantly by the spleen. In contrast to experimental Heinz body anemia in animals, Heinz bodies were present even in the nucleated cells.