Assessment of Serum Uric Acid Levels in Multiple Sclerosis during Disease-Modifying Treatment

Abstract

Objective: Uric acid is a potent endogenous antioxidant and scavenger of peroxynitrite (PN), which hypothesized to be involved in the pathogenesis of multiple sclerosis (MS). Some studies reported lower levels of UA in MS patients compared with controls, whereas other studies found no difference. The main purpose of this analysis was to verify the hypothesis on lower serum levels of UA in MS patients compared with controls.Materials and methods: We examined 80 patients with clinically defined MS, according to the McDonald’s criteria and 53 patients of controls group (non-inflammatory neurological diseases, excluding vascular disorders). Uric acid concentration was determined by using a commercially available enzymatic colorimetric assay according to the manufacturer’s instructions.Results: Serum UA levels of MS patients were significantly lower (4.2 ± 1.1 mg/dl) when compared with control group (4.9 ± 1.4 mg/dl, P=0.0092). Correlation between MS duration and serum UA concentration did not reach statistical significance, however the tendency showing that patients who are suffering from this disorder for a longer time have lower serum UA concentration was observed. Moreover, we found a statistically significant correlation between disease duration and UA concentration in a subgroup of patient who did not have a history of mitoxantrone intake (P<0.0321).Conclusion: Although we do not know exactly whether and how uric acid is involved in MS pathogenesis, data suggest that UA concentration is lower in MS patients than in control group. It seems that low uric acid levels indicate patients with a higher risk of disease progression. Whether or not UA concentration can be useful as a biomarker in MS requires further study.