A Rare Case of Tubulointerstitial Nephritis and Uveitis Syndrome Treated with a Multi-Specialty Approach

BACKGROUND It is important for an ophthalmologist and nephrologist to look for hidden causes of uveitis and nephritis, respectively. Delay in diagnosis leads to increased morbidity and failure to systemically manage the patient results in future recurrence of disease. It is likely that TINU remains underdiagnosed and could potentially account for some of the cases of idiopathic uveitis, especially when greater than 50% of uveitis cases have no identifiable cause. Fewer than 300 cases of tubulointerstitial nephritis and uveitis (TINU) syndrome have been reported. In TINU syndrome, inflammation affects the renal tubules, interstitial tissue, and uveal tract. Its pathogenesis remains poorly understood. CASE REPORT We report a rare case of TINU syndrome in a 23-year-old female who was treated using a multispecialty approach. Her primary care physician diagnosed her with proteinuria and acute kidney injury and referred her to the nephrologist, who later referred her to the ophthalmologist. A left kidney biopsy confirmed acute interstitial nephritis. Following the discovery of a "pink eye", the patient was referred to ophthalmology and diagnosed with anterior uveitis, confirming TINU syndrome. Without the additional findings of uveitis, the diagnosis would have been missed. Resolution was obtained through steroid therapy. CONCLUSIONS Correctly diagnosing TINU syndrome requires a multispecialty approach and may not be obvious upon initial presentation. Therefore, the ophthalmologist needs to consider TINU in the differential diagnosis for a patient with bilateral uveitis and evaluate a urinalysis for proteinuria as part of the work up.