Acute Interstitial Nephritis after Single Dose of Ketorolac.

Acute interstitial nephritis (AIN) is an immunologically mediated cause of acute kidney injury (AKI), most often drug-induced, with NSAIDs being a leading culprit. We present a 39-year-old woman who developed biopsy- proven AIN following a single intramuscular dose of ketorolac, an exceptionally short latency likely due to prior sensitization. Despite lacking classic systemic features, she exhibited non-oliguric AKI that improved rapidly with corticosteroids. This case underscores that NSAID-induced AIN can occur even after minimal exposure, highlighting the importance of early recognition, drug withdrawal, and timely steroid therapy to optimize renal recovery.