TINU Syndrome: round trip from the eye to the kidney

Key words: TINU, Uveitis, Tubulointerstitial nephritis, Urine stix

TINU stands for TubuloInterstitial Nephritis and Uveitis syndrome. The effective incidence of the disease is unknown, but it probably still remains largely underestimated. This can be explained by the frequent existence of a time-gap between the occurrence of the two conditions. In addition while uveitis is generally symptomatic with the classical clinical presentation of red and painful bilateral eyes, nephritis is often silent. As to their evolution the nephritic involvement tends to be self-limiting, while uveitis can progress to permanent eye damage and requires the use of topic and systemic corticosteroids and sometimes immunosuppressant drugs. It is advised to perform a simple urine stix in all new cases of uveitis and to repeat it during the follow-up of apparently idiopathic uveitis. On the other hand it is important to seek an ophtalmological evaluation in all the cases of unexplained tubulointerstitial nephritis to rule out the presence of a silent uveitis.