Splenic Function in Amyloidosis

Abstract

Thirteen of 62 patients (21%) with biopsy-proven amyloidosis seen between 1971 and 1983 had evidence of functional hyposplenism, as defined by the presence of Howell-Jolly bodies on blood smear and anatomic presence of the spleen. The latter was established by various imaging procedures, surgery, or autopsy. The patients with functional hyposplenism (9 men, 4 women) ranged between 33 and 79 years of age. Proteinuria, hepatomegaly, gastrointestinal bleeding, and cardiovascular manifestations were common presenting findings. Twelve patients exhibited Howell-Jolly bodies initially and 9 were anemic. In no case was there evidence of megaloblastic dyspoiesis. Eleven patients had a plasma cell dyscrasia; the light chain component in all was lambda. Marrow plasmacytosis ranged between 3 and 50%; no patient had lytic bone lesions or hypercalcemia. Surgery or autopsy in 8 patients disclosed spleen weights between 110 and 500 grams; all were extensively replaced with amyloid. Three patients had normal spleen scans and normal size spleens at autopsy. None of the patients with functional hyposplenism developed pneumococcal infections and one has survived for 70 months. Although splenic function is generally unaltered or increased in the presence of infiltrative lesions, amyloidosis occasionally causes splenic hypofunction which may serve as a useful diagnostic clue. We are unaware of any instance of functional hypersplenism with amyloidosis.