Systemic lupus erythematosus and Castleman's disease.

Lymphadenopathy is a common finding in systemic lupus erythematosus (SLE), yet lymphoid malignancy is rare. Typically, adenopathy associated with SLE responds to glucocorticoid therapy. We evaluated a patient with a diagnosis of SLE who had progressive lymphadenopathy despite receiving aggressive corticosteroid therapy for SLE associated thrombocytopenia. Histopathology initially revealed an aggressive plasmacytosis characteristic of Castleman's disease (CD). CD, or angiofollicular hyperplasia, is a rare lymphoproliferative neoplasm that has features overlapping many autoimmune diseases. This disorder should be considered in autoimmune diseases with unremitting or progressive adenopathy.