Acute interstitial nephritis with glomerulopathy due to nonsteroidal anti-inflammatory agents: a review of its clinical spectrum and effects of steroid therapy.

We reviewed case reports of patients who developed acute renal failure and/or nephrotic range proteinuria in the course of receiving treatment with nonsteroidal anti-inflammatory agents (NSAIA). Those cases that contained information sufficient to confirm the diagnosis of acute interstitial nephritis with glomerulopathy (AING), including a suggestive clinical syndrome with appropriate renal biopsy findings, were further analyzed to achieve a more complete description of this clinical entity and its responsiveness to steroid treatment. Analysis of the cases that fulfilled the inclusion criteria confirmed that the disorder is twice as common in women and occurs mainly in elderly people, usually after long-term use of NSAIAs for musculoskeletal problems. Fenoprofen was implicated in 47% of the cases. Evidence of systemic hypersensitivity was uncommon. Two thirds of the cases displayed clinical and/or histological evidence of both acute interstitial nephritis and increased glomerular permeability. These findings strongly suggest that this condition is distinct from other drug-induced "allergic" acute interstitial nephritides. In the absence of complicating factors, all patients improved following discontinuation of the offending agents. No evidence was found to suggest that steroid therapy altered the clinical course of this process.