A 47-year-old man presented with fever of unknown origin, generalized weakness, edema, and renal failure. He had left-sided pleural effusion, generalized lymphadenopathy, multiple nontender cutaneous nodules, hepatomegaly, renal failure, and hypergammaglobulinemia. Axillary lymph node biopsy showed findings consistent with Castleman disease of the hyaline vascular type associated with interfollicular plasmacytosis. A renal biopsy performed in view of proteinuria and acute renal failure showed hypercellular glomeruli with capillary loop thickening and double contours consistent with membranoproliferative glomerulonephritis. Skin nodule biopsy showed a glomeruloid hemangioma characterized by dermal proliferation of capillary loops in a nodular manner resembling a glomerulus. He experienced clinical and biochemical remission with steroids. Discontinuation of steroid therapy was associated with recurrence of renal failure, reappearance of nodules, lymphadenopathy, and appearance of bony lytic lesions. Biopsy of bony lytic lesions showed plasmacytoma. The patient achieved complete remission on treatment with steroids and cyclophosphamide and is free of symptoms at the end of 40 months of follow-up. To our knowledge, this is the first case report of the occurrence of membranoproliferative glomerulonephritis, glomeruloid hemangioma of the skin, and plasmacytoma in a patient with multicentric Castleman disease without human immunodeficiency virus infection.