Comparison of anti-H.pylori therapeutic responses in two groups of patients with and without cagA Ab

CagA antigen is found in 60-80% of Helicobacter Pylori organisms. It seems that CagA positive strains have more virulance. The aim of this study was to compare the eradication rate of CagA positive and CagA negative genotypes using current quadruple regimens.

The patients who had positive results for Helicobacter Pylori after endoscopy in Hazrat-Rasool Hospital were enrolled into the study. In 56 patients with positive rapid urease test (RUT), Anti CagA was determined and a 2-week quadruple regimen (Omeprazole, Amoxicilin, Metronidazole, and Bismuth) was prescribed. The UBT was performed two months after the end of treatment.

Of 56 patients who were infected with Helicobacter Pylori, 36 (64.3%) had CagA antibody. 15 (26.8%) patients had positive UBT and 41 (73.2%) patients had negative tests. The success rate of treatment was 69.44% (25 patients) in CagA positive and 80% (16 Patients) in CagA negative participants. This difference was not statistically significant (P=0.533).

The presence of CagA is associated with higher success rate in conventional triple regimens but sufficient data for quadruple therapeutic regimens are not available. We did not find any association between CagA positivity and eradication rate of H.pylori.