[Renal failure associated with polyarteritis nodosa]

We reported 5 patients with renal failure associated with polyarteritis nodosa (PN). In all patients the renal dysfunction became apparent from 2 to 4 weeks after the onset of fever or neuromuscular symptoms with laboratory findings supporting marked inflammatory process and took the course of either acute or rapidly progressive renal failure. The clinical diagnoses on admission were variable; fever of unknown origin, peptic ulcer disease, polyneuritis multiplex, disseminated intravascular coagulation and Buerger's disease. Microscopic examination of the kidneys in 3 by renal biopsy and in 2 by autopsy revealed crescentic glomerulonephritis without immunoglobulin deposit, segmental necrotizing glomerulonephritis, marked inflammatory infiltrate around the glomeruli, granulomatous lesion, tubular necrosis and cortical necrosis other than necrotizing vasculitis. The outcomes were favorable with prednisolone monotherapy in two patients who had biopsy-proven diagnosis and treatment early in the course. Of all PN the prevalence of renal involvement is considered to be about 70%, the prognosis of which has been considered very poor. However it seems possible to alter fatal outcome of this disease by starting treatment with confident histological proof early in the disease process.