Detection of Helicobacter Pylori in Oropharyngeal Diseases

Abstract

Objective: Helicobacter pylori (HP) is a well-known gastric pathogen. Recently it was also found in the oropharyngeal tissue. The direct impact of HP on oropharyngeal pathogenesis was not satisfactorily proven. HP strains differ according to the virulence factor genes carried. The presented study focused on detection and genotyping of oropharyngeal HP. Method: A total of 104 patients were enrolled. The blood and tissue specimens from patients with tonsillar cancer (n = 41), chronic tonsillitis (n = 38), and obstructive sleep apnea syndrome (OSAS) (n = 25) were collected. Anti-HP antibody levels were detected. Detection of HP strains and genotyping for establishment of cagA and vacA genes status was performed by real-time PCR. Results: Serum antibodies were positive in 32 (78.05%) cancer patients, 13 (34.21%) chronic tonsillitis patients, and 18 (72%) OSAS patients. Statistically significant differences were found between tumor and tonsillitis groups and between OSAS and tonsillitis groups (Chi-square, P = .0001, P = .0049). 56 specimens (23 carcinoma, 20 chronic tonsillitis, and 13 OSAS) were investigated using real-time PCR. Tissue specimens were positive in 17 (73.91%) tumors, 14 (70.0%) tonsillitis, and 9 (69.23%) OSAS. No statistically significant differences were found among all groups. PCR genotyping of oropharyngeal HP strains showed the majority of s1b (56.7%) and m2 (59.5%) alleles of vacA and low presence of cagA gene (13.5%). Conclusion: Oropharyngeal HP was found in a high number of cases. Its distribution among different pathologies does not support the hypothesis of its direct carcinogenic potential. Presence of less virulent strains confirms this finding. The possibility of influencing local immune response leading to chronic inflammation or idiopathic hypertrophy of tonsillar tissue was not excluded.