Clinical and Genetic Features of Tubulointerstitial Nephritis and Uveitis Syndrome with Long-Term Follow-Up

PURPOSE: To investigate the clinical manifestations, prognosis, and HLA-type of tubulointerstitial nephritis and uveitis syndrome (TINU) with long-term follow-up. METHODS: Clinical data of five patients with TINU were retrospectively reviewed. RESULTS: The mean age was 15.8 years. The mean follow-up periods were 54.0 months. The initial subjective symptoms were bulbar injection (100%), ocular pain (80%), and blurred vision (60%). The medical department that the patients visited first was ophthalmology in 4 (80%) cases. Urinalysis showed the characteristic increase of the β2 microglobulin in all (100%) patients. Uveitis and nephritis were diagnosed within 1 week from each other. Although two showed recurrences, the topical and systemic steroid treatment with mean duration of 14.1 months brought the resolution of nephritis and uveitis in all patients. Recurrence-free periods ranged from 12 to 71 months. The final visual outcome was 20/20 or better in all cases. HLA-DR4 or the allele of DRB1(∗)04 was present in all (100%) patients. CONCLUSIONS: TINU should be considered in the differential diagnosis in young patients with uveitis of unknown origin and renal dysfunction. Urinary β2 microglobulin level and HLA typing may help in the diagnosis of TINU. The prognosis for patients with TINU is generally good with steroid treatment.