We report on a patient who suffered from psoriasis vulgaris and psoriatic arthritis and developed nephrotic syndrome after long-term therapy with non-steroidal anti-inflammatory drugs. Membranous nephropathy with tubulointerstitial and vascular (intimal hyperplasia) changes were found on renal biopsy using optical, immunofluorescent and electron microscopy. Treatment with methylprednisolone "pulse" therapy (1 g/24 h during 3 days) and continuing with prednisone 0.5 mg/kg/24 h was ineffective and end-stage renal failure developed 6 months after the diagnosis had been established.