Hereditary Spherocytosis : II. Observations on the Role of the Spleen

1. Three patients with hereditary spherocytosis and 1 patient with the Fanconi syndrome (pancytopenia and multiple congenital abnormalities) were transfused prior to splenectomy with normal erythrocytes of types which could be differentiated serologically from those of the recipients. The proportions of donated and patient’s cells in peripheral blood and in blood washed from the minced spleens were determined by differential agglutination, and the osmotic and mechanical fragilities of the two types of cells in peripheral and splenic blood were measured by differential agglutination of the corpuscles remaining in each test tube after partial hemolysis had occurred.

2. In each case of hereditary spherocytosis the proportion of recipient’s cells was much higher in splenic than in peripheral blood, indicating selective retention of the thicker corpuscles within the spleen. Osmotic fragility of thie patient’s red cells was much greater in samples of splenic mince blood than in peripheral venous samples, while the fragility of the donated red corpuscles was normal or nearly normal in both splenic and peripheral blood.

In the patient exhibiting the Fanconi syndrome, on the other hand, neither the patient’s red cells nor donated red cells were retained to any extent in the spleen and the fragility of neither type of cell was altered.

3. Spleens removed surgically from 3 patients with idiopathic thrombocytopenic purpura were perfused with mixtures of normal A or B cells and group O cells drawn from a splenectomized individual with hereditary spherocytosis. During perfusion the spheroidal cells were selectively removed from the mixtures and at the end of each experiment red cells of this type predominated in the blood samples washed from the minced spleens. A fourth excised spleen was perfused with a mixture of two types of normal cells, neither of which was retained to any extent by the spleen during perfusion. The perfusion experiments show that spleens from patients with nonhemolytic disease are also capable of selective trapping of spheroidal cells.

4. The experiments described indicate that the spleen acts as a filter and trap and as an "incubator" in accelerating destruction of red corpuscles in patients with hereditary spherocytosis.