POEMS syndrome with renal plasmacytoma and classic polyarteritis nodosa: a case report.

POEMS syndrome is a rare conglomeration of disorders associated with plasma cell dyscrasia. The acronym POEMS is derived from main features of the syndrome namely 'polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin lesions'. Other clinical features include presence of sclerotic bone lesions, Castleman's disease, papilledema, pleural effusion, edema, ascites, erythrocytosis and thrombocytosis. Myeloma is the most common plasma cell dyscrasia associated with POEMS syndrome. Renal involvement is rare and renal biopsy is characterized by glomerular involvement with membranoproliferative glomerulonephritis and endothelial injury. We report a case of a 67-year-old male who presented with clinical features satisfying the diagnostic criteria of POEMS syndrome and had rapidly progressive renal failure. Renal biopsy showed extensive interstitial infiltration by plasma cells and concomitant presence of classic polyarteritis nodosa. Although association with small-vessel vasculitis has been reported in patients with POEMS syndrome, to the best of our knowledge, this is the first report of POEMS syndrome associated with medium-sized vessel vasculitis.