Control of auto-immune thrombocytopenia by removal of an atrophic spleen: a case report.

We report a patient with systemic lupus erythematosus in whom resection of a completely atrophic spleen (weight 5 g) reversed steroid-refractory thrombocytopenia. The spleen plays a central role in the pathogenesis of autoimmune thrombocytopenia by synthesizing antibodies directed against autologous platelets and by sequestering these immunoglobulin-coated cells. Both functional disturbances occur without splenic enlargement, and splenectomy wll, in selected cases, improve thrombocytopenia. A similar rise in platelet count may follow resection of much smaller masses of splenic tissue such as splenunculi. We have, however, been unable to find documentation of this phenomenon after removal of a completely atrophic spleen.