Background: Crohn disease (CD) is a chronic inflammatory bowel disease often accompanied by periodontal symptoms. Based on its function in immune response, tumor necrosis factor (TNF)-α and its genetic variants have been discussed as risk indicators in inflammatory processes. Therefore, the aim of the present study is to investigate the impact of TNF-α polymorphisms on periodontal parameters and inflammatory lesions of oral mucosa as a characteristic of CD.
Methods: A total of 142 patients with CD were included in the study. Oral soft tissue alterations and periodontal parameters were assessed. Genotypes, alleles, and haplotypes of TNF-α polymorphisms (rs1800629, cDNA-308G > A; and rs361525, cDNA-238G > A) were determined by polymerase chain reaction with sequence-specific primers (PCR-SSP).
Results: Patients with CD who exhibit more severe oral soft tissue alterations were significantly more often A allele carriers of rs361525 than G allele carriers (14.2% versus 2.2%; P <0.001). Furthermore, A allele carriers had a higher mean periodontal probing depth (P <0.05), mean clinical attachment level (P <0.05), and sites with bleeding on probing (not significant). Similar results were obtained when evaluating A allele-containing genotypes (AG + AA) and haplotypes (GA). In multivariate analyses considering age, sex, smoking, and medication as confounders, the A allele was proven to be an independent risk indicator for oral soft tissue alterations in patients with CD. No genotype-dependent influence of rs1800629 was observed.
Conclusion: The TNF-α A allele of rs361525 represents a significant risk indicator for oral soft tissue alterations in patients with CD.
Keywords: Crohn disease; inflammation; periodontitis; polymorphism, single nucleotide; tumor necrosis factor-alpha.