Salivary interleukin-17A and interleukin-18 levels in patients with Celiac disease and periodontitis

Background: Previous studies have shown that IL-17A and IL-18 are elevated in the serum and intestinal mucosa of celiac disease patients and were correlated with the severity of villous atrophy and inflammation. The aim of this study was to investigate the levels of salivary interleukin-17A, interleukin -1beta, and interleukin-18 in celiac disease patients under gluten-free diet with and without periodontitis and compare them with healthy controls.Methods: A total of 23 participants with confirmed serological analysis of celiac disease (CD) and 23 control subjects were involved in this study. Celiac disease patients were on a gluten-free diet (GFD) for at least one year and had no other autoimmune disorders. Demographic data, periodontal examination, unstimulated whole saliva collection and enzyme-linked immunosorbent assay for salivary interleukin-17A, interleukin-1 beta, and interleukin-18 levels were performed. Spearman's correlation analysis was used to evaluate the associations between CD markers in patients under GFD and their periodontal clinical findings.Results: Periodontal findings showed significantly lower values in celiac disease patients under gluten-free diet than control subjects (p=0.001). No significant difference was observed regarding salivary IL-17A, IL-18 and IL-1B between celiac disease and control subjects. However, all interleukins levels were higher in periodontitis patients in both celiac and the control group. IL_1Beta level was significantly higher in periodontitis patients than non-periodontitis patients in the control group (p=0.035). Negative significant correlations were observed between serum IgA level and plaque index (r=-0.460, p=0.010), and gingival index (r=-0.396, p=0.030) in CD patients under gluten-free diet. Conclusion: Celiac disease patients under gluten-free diet had better periodontal health than control subjects, but increased salivary IL-17A, IL-18 and IL-1B levels is associated with periodontitis. Serum IgA level was significantly inversely associated with periodontitis clinical manifestations and with salivary inflammatory mediators in CD patients under GFD.</p