Acute Renal Failure Unmasking Tubulointerstitial Nephritis and Uveitis (TINU) Syndrome in A Young Male: A Case Report and Literature Review

Background: Tubulointerstitial nephritis and uveitis (TINU) syndrome is a rare and underdiagnosed cause of acute kidney injury (AKI) in young patients. It combines acute interstitial nephritis with uveitis and is frequently overlooked because renal and ocular manifestations may occur asynchronously. Case Presentation: We report the case of a previously healthy 25-year-old military man admitted for unexplained AKI, with a peak serum creatinine of 5.2 mg/dL and urea 0.64 g/L. Laboratory evaluation revealed a tubular profile with low-grade proteinuria (320 mg/day), sterile urine, and normal electrolytes. Inflammatory markers were mildly elevated (CRP 15 mg/L), while immunology and infectious serologies were negative. Renal ultrasound showed normal-sized kidneys without obstruction. A history of sporadic NSAID intake for back pain was noted. Ophthalmological consultation, prompted by suspicion of TINU, revealed bilateral non-granulomatous anterior uveitis. Renal biopsy was deferred because of progressive recovery under therapy. Management and Outcome: The patient received intravenous rehydration and oral prednisone (1 mg/kg/day) for nephritis and topical corticosteroids for uveitis. Dialysis was not required. Renal function improved within three weeks, with serum creatinine returning to 1.5 mg/dL. Ocular inflammation resolved completely. At early follow-up, no relapses were observed. Conclusion: This case illustrates a typical presentation of TINU syndrome in a young adult with AKI. The asynchrony between renal and ocular findings emphasizes the need for multidisciplinary collaboration. NSAID exposure may have contributed as a potential trigger. Early recognition and corticosteroid therapy led to full recovery.