Background: Helicobacter pylori causes gastric inflammation secondary to the mucosal release of cytokines and tumour necrosis factor-alpha.
Aims: To investigate whether serum levels of tumor necrosis factor-alpha correlate with Helicobacter pylori infection, CagA antibodies, 13C-urea breath test results, endoscopic, and histological findings.
Methods: Endoscopy (with gastric biopsies), 13C-urea breath test, and serological assay of CagA antibodies and tumour necrosis factor-alpha were performed in 172 dyspeptic patients.
Results: A total of 126 patients (73.2%) were infected; of the 126 patients, 84 with CagA antibodies (66.7%) showed a higher prevalence rate of duodenal ulcer (p = 0.03), more severe neutrophil infiltration (p = 0.03) and higher bacterial colonization (p = 0.03) than those without antibodies. CagA+ and CagA- groups differed also in 13C-urea breath test results (p = 0.03). A significant difference in serum tumour necrosis factor-alpha levels was observed between infected and uninfected individuals (p = 0.03) as well as between CagA+ and CagA- patients (p = 0.002).
Conclusions: Helicobacter pylori infection is associated with increased serum levels of tumour necrosis factor-alpha. Subjects who harbour CagA positive strains have more severe mucosal damage, higher bacterial colonization, higher probability of developing duodenal ulcer and higher serum levels of tumour necrosis factor-alpha than those infected with CagA- strains.