ELECTRON MICROSCOPIC STUDIES OF THE SPLEEN AND LIVER IN HEREDITARY SPHEROCYTOSIS

Electron microscopic findings of the red pulp of the spleen and liver from three patients with hereditary spherocytosis have been reported.
The sinus lumen of the spleen contained various amounts of red cell with reduced deformability. Pronounced engorgement of erythrocytes in the cordal space and various stages of erythrophagocytosis by the cordal macrophages were characteristic findings. The sinus lining cells also showed erythrophagocytosis and contained numerous dense bodies. Cordal macrophages and fibrous elements seemed to be more increased in the older patient.
Acid phosphatase activity of varied intensity was demonstrated in the erythrophagocytic vacuoles of cordal macrophages. As the intracellular degradation progressed, more intense activity of this enzyme was noted, indicating their lysosomal origin.
Splenic conditioning and enhanced destruction of defective red cells in the spleen were the main cause of hemolysis in hereditary spherocytosis.
In the liver, erythrophagocytosis by the Kupffer cells was also not infrequently noted, but the liver was estimated to play a minor role in HS.
The mechanism of hemolysis and the role of the spleen and liver in elimination of hereditary spherocytes have been discussed.