Expression of cytokines in the gingival crevicular fluid and serum from patients with inflammatory bowel disease and untreated chronic periodontitis

Background and Objective: Previous studies have reported an increased prevalence/severity of chronic periodontitis in patients with inflammatory bowel disease. However, the pathogenesis of periodontal lesions in such patients has not been characterized. The aim of this pilot study was to characterize the pattern of expression of cytokines in the gingival crevicular fluid and serum from patients with untreated chronic periodontitis and Crohn's disease, ulcerative colitis and systemically healthy controls. Material and Methods: Fifteen patients with Crohn's disease, 15 patients with ulcerative colitis and 15 controls participated in the study. All subjects had been diagnosed with untreated chronic periodontitis. The clinical parameters evaluated were clinical attachment loss, bleeding on probing and percentage of plaque. The gingival crevicular fluid was sampled from four shallow and four deep periodontal sites of each patient. The concentrations of the cytokines interleukin (IL)-1 beta, IL-4, IL-6, IL-10, IL-12p40, IL-12p70, interferon-gamma and tumor necrosis factor-alpha were measured using a commercially available Lincoplex kit and the concentration of IL-18 was measured using an ELISA. Results: Multiple comparisons analysis showed that clinical attachment loss, bleeding on probing, percentage of plaque and volume of gingival crevicular fluid were similar across the groups. The concentration of IL-4 in the gingival crevicular fluid differed significantly between groups in shallow sites (p = 0.046), with higher values found for the controls. In serum, the concentration of IL-18 was also significantly different between groups, with lower values found for controls (p = 0.018). Conclusion: This study showed a higher concentration of IL-18 in serum, but not in the gingival crevicular fluid, from periodontitis patients with Crohn's disease or ulcerative colitis compared with controls. The expression of cytokines was similar in the gingival crevicular fluid from patients with untreated chronic periodontitis who also had Crohn's disease or ulcerative colitis and in systemically healthy controls with untreated chronic periodontitis.