Studying zonulin levels in patients with inflammatory bowel disease and peripheral arthritis

BACKGROUND: Currently, disruption of the barrier function of the intestinal mucosa is considered one of the key mechanisms in the pathogenesis of extraintestinal manifestations of inflammatory bowel diseases, especially damage to the musculoskeletal system.

AIM: To study the relationship between the level of zonulin in blood serum and the parameters of the immune status in patients with inflammatory bowel diseases in combination with peripheral arthritis.

MATERIALS AND METHODS: 97 patients with ulcerative colitis and Crohn’s disease have been examined, with peripheral arthritis verified in 47 patients; the control group included 50 patients without peripheral arthritis. Zonulin, tumor necrosis factor α, interleukin-1β, -10, -17A, -23 were determined in blood serum using standard kits for direct enzyme immunoassay.

RESULTS: Patients with peripheral arthritis were younger with an earlier onset of inflammatory bowel diseases (p < 0.001). When assessing the concentration of serum zonulin in the patients with and without arthritis, no significant differences have been found. In the patients with peripheral arthritis, zonulin concentration directly correlated with the level of interleukin-17A (r = 0.323; p = 0.039), interleukin-23 (r = 0.321; p = 0.041).

CONCLUSIONS: According to the data obtained, the use of zonulin as a marker of peripheral arthritis in inflammatory bowel diseases is not recommended. Nevertheless, the correlation of zonulin and the concentrations of interleukin-17А and -23 demonstrates its role in the regulation of mucosal immunity in the development of extraintestinal manifestations of inflammatory bowel diseases.