Introduction: Helicobacter pylori vacA and cagA genes are associated with higher virulence. TNF-α has an important role in host defense against H. pylori infection.

Aim. The purpose of this study was to investigate the relationship between TNF-α serum levels with cagA and vacA genes in H. pylori infection.

Methods: A cross sectional study was done on eighty patients that consecutively admitted to endoscopy unit. Diagnosis of H. pylori infection was based on rapid urease test. Serum samples were obtained to determine circulating TNF-α level. Polymerase chain reaction was done to examine H. pylori vacA and cagA genes. Data analysis was carried-out using SPSS version 22 with 95% CI and p value <0.05 was considered statistically significant.

Results: There were 45 (56.3%) patients infected with Helicobacter pylori. There were 33 (73.3%) patients with H. pylori cagA positive. Serum TNF-α levels in patients with the H. pylori positive were significantly higher compared to the patients with negative H. pylori. Serum level of TNF-α were significantly higher in cagA positive than negative.

Conclusion: The more virulence of H. pylori, cagA gene, the higher serum TNF-α levels were found.

Keywords: Helicobacter pylori, TNF-α, cagA gene, vacA gene, gastritis.