Urinary neopterin levels in uveitis: is it a new activity marker?

PURPOSE: Neopterin is an immunologic marker for the activation of the cell-mediated immune system and it is found to be elevated in autoimmune diseases. We aimed in this study to investigate the relationship between urinary neopterin levels and disease activity in patients with uveitis. METHODS: 31 patients with active uveitis and 13 patients with inactive uveitis were compared with 27 age and sex matched controls. Disease activity was evaluated by clinical examination and fundus florescein angiography findings. Samples were studied with High Performance Liquid Chromatography. RESULTS: Urinary neopterin levels in patients with active uveitis, inactive uveitis and control subjects were 274 +/- 98, 179 +/- 61 and 166 +/- 38 micromol/mol creatinine respectively (p < 001). The difference between active uveitis, inactive uveitis and control groups were statistically significant (p < 001). CONCLUSIONS: Urinary neopterin levels are found to be increased in patients with active uveitis. Neopterin can be used as a biochemical activity marker to support the clinical findings in patients with uveitis.