Chronic nephrotoxicity of anti-inflammatory drugs used in the treatment of arthritis.

We determined the consumption of non-steroidal anti-inflammatory drugs (NSAIDs) and the prevalence of chronic renal impairment and renal papillary necrosis (RPN) in patients with various types of arthritis. Ninety-four patients with chronic arthritis who had consumed more than 1000 capsules and/or tablets of NSAIDs were studied. Renal profiles and radiological investigations such as intravenous urogram (IVU), ultrasonography (US) and computed tomography (CT) were performed to look for evidence of RPN. Twelve patients did not complete the study. Ten of the 82 patients who had completed the study (12.2%) had radiologic evidence of RPN. Five out of 53 patients (9.4%) with rheumatoid arthritis, three out of 11 patients (27.3%) with gouty arthritis and two out of seven patients (28.6%) with osteoarthritis had RPN. Renal impairment (serum creatinine levels of 125-451 mumol/l) was found in 20 patients (24.4%). The patients had consumed 1000-26,300 capsules and/or tablets over a period ranging from 1 yr to more than 30 yr. Patients with chronic arthritis who consume excessive amount of NSAIDs are at risk of developing RPN and chronic renal impairment.