An Atypical Presentation of Tubulointerstitial Nephritis With Uveitis ( <scp>TINU</scp> ) in an Older Patient Requiring Emergency Dialysis: A Case Report

Tubulointerstitial nephritis with uveitis (TINU) is an immune-mediated systemic disorder most commonly described in adolescents and young adults, and its recognition in older patients remains challenging. We report the case of a 58-year-old woman who presented with systemic symptoms and rapidly progressive acute kidney injury. Renal function deteriorated significantly, necessitating emergency hemodialysis. Renal biopsy demonstrated acute tubulointerstitial nephritis with diffuse interstitial inflammation and minimal fibrosis. During hospitalization, ocular symptoms were identified, and a comprehensive ophthalmologic examination confirmed intermediate uveitis, establishing the diagnosis of TINU syndrome. Treatment with standard-dose corticosteroid therapy resulted in rapid clinical improvement, recovery of urine output, and discontinuation of dialysis within a short period. Renal function and ocular inflammation improved in parallel. Corticosteroids were gradually tapered without relapse. At long-term outpatient follow-up on September 15, 2025, the patient remained clinically stable, with serum creatinine levels ranging from 60 to 70 μmol/L and no recurrence of uveitis. This case highlights an atypical presentation of TINU in an older patient complicated by severe acute kidney injury requiring dialysis and underscores the importance of considering TINU in patients with unexplained acute kidney injury and ocular manifestations, regardless of age. Early recognition and appropriate immunosuppressive therapy are essential for favorable renal and ocular outcomes.