Nonsteroidal antiinflammatory drug induced acute granulomatous interstitial nephritis

Background: Acute interstitial nephritis is a common cause of acute kidney injury (AKI). The granulomatous inflammation is rarely but often manifests as a form of a granulomatous interstitial nephritis (GIN) in the kidney. Acute granulomatous interstitial nephritis is mainly associated with drugs, infection and autoimmune diseases. Case presentation: A 44-year-old-male visited our out-patient department with symptoms of nausea, vomiting, and general weakness that had developed over the previous 2 weeks. He had history of medication, nonsteroidal anti-inflammatory drugs. On admission to the general ward, his serum creatinine level was markedly elevated. GIN was confirmed by renal biopsy and 30 mg of corticosteroid per day was immediately initiated. Subsequently, his serum creatinine level and uremic symptoms dramatically decreased. Conclusion: Acute granulomatous interstitial nephritis is a rare but important disease on AKI. As long as we can carefully exclude infectious diseases as the cause of granulomatous lesion, acute granulomatous interstitial nephritis can be treated with steroid regardless of the etiologies. Since there is no proven treatment for the GIN yet, we can carefully suggest that moderate to high dosage corticosteroid can be helpful for prognosis in case of acute granulomatous interstitial nephritis of patients with AKI.