Glomerulonephritis, non-Hodgkin's lymphoma and leucocytoclastic vasculitis

2 cases of active focal proliferative glomerulonephritis, lymphocytic malignant lymphoma and leucocytoclastic vasculitis are described. 1 presented with the nephrotic syndrome and progressive renal impairment, the other with acute renal failure. Cryoglobulins were detected in the serum of 1 patient, but not in that of the other. Initial renal and skin biopsies in the 2 patients were strikingly similar. As well as demonstrating glomerular lesions, the renal biopsies contained interstitial lymphomatous infiltrate which, in 1 case, was initially incorrectly interpreted and resulted in delay in specific treatment. Immunosuppressive therapy markedly improved renal function and induced remission of the vasculitis and lymphoma. Repeat renal biopsy in 1 case confirmed regression of the glomerulonephritis. A common immunological aetiology may explain the co-existence of these three conditions in the 2 patients.