Dynamic Thiol/Disulphide Homeostasis as Oxidative Stress Marker in Ankylosing Spondylitis and Undifferentiated Spondyloarthropathy.

AIM: Seronegative spondyloarthropathies (SpA) are a group of chronic diseases, characterized by axial inflammation, oligoarthritis, and enthesitis. Oxidative stress may contribute to a wide range of diseases such as rheumatologic diseases including SpA. This prospective case-control study was designed to compare the thiol-disulfide levels as a marker of oxidative stress in SpA patients with healthy controls.

METHODS

A total of 144 patients who were diagnosed as undifferentiated spondyloarthropathy (UspA, n=97), ankylosing spondylitis (AS, n=47), and 80 healthy controls were included. Serum native thiol (NT), total thiol (TT), disulfide (D) levels were measured with the fully automated Erel?s method. NT/TT, D/TT, and D/NT ratios were calculated. Thiol-disulfide levels were compared between SpA groups and healthy controls.

RESULTS

NT and NT/TT ratios were found to be significantly lower in the SpA group. (p<0.001). Disulfide, D/NT, and D/TT ratios were found to be significantly higher in the SpA group (p <0.001 for each comparison). In pairwise comparisons between SpA subgroups, NT and TT levels were lower in USpA group compared to AS group (P=0.021). Serum disulfide levels were higher in USpA group compared to AS group (P=0,004). Anti-tumor necrosis factor (Anti-TNF) group had lower TT measurements compared to the classical disease-modifying anti-rheumatic drugs (cDMARD) group in patients with SpA (P=0.039).

CONCLUSION

Thiol-disulfide balance is disturbed in favor of disulfide in SpAs patients compared to healthy volunteers. Native and total thiol measurements correlate with acute phase reactants and might be used to monitor disease activity. Anti-TNF therapy might control the oxidative degenerative process better than the classical DMARD in SpA patients.