Relationship Between Drug Resistance and cagA Gene in Helicobacter pylori

Abstract

Background: Currently, there are evidences for the existence of diverse strains of Helicobacter pylori with different levels of virulence. In other way, the most important reason of therapeutic failure is resistance to the antibiotics. Objectives: The aim of this study was to evaluate the relationship between H. pylori drug resistance and the presence of cagA gene. Patients and Methods: Gastric biopsy specimens were cultured for H. pylori isolation. Resistance to antimicrobial agents, including clarithromycin, metronidazole, and amoxicillin were detected by modified disk agar diffusion tests. The cagA gene was detected using PCR, and the results were analyzed by χ2 and Fishers exact tests using SPSS software version 16. Results: A total of 123 H. pylori-positive patients (68 males, 55 females, mean age 35 ± 18 years old) were studied. The rate of resistance to clarithromycin, metronidazole and amoxicillin were 17.07, 78.86 and 27.64%, respectively. In this study, the cagA was detected in 84 of 123 strains (68.3%). The frequency of resistance to clarithromycin, metronidazole and amoxicillin in cagA positive confirmed microorganisms were, 16 (13.01%), 67 (54.47%) and 24 (19.51%), respectively. While the results for cagA negative ones were 5 (4.06%), 30 (24.39%) and 10 (8.13%), respectively. Conclusions: Our results indicated that the overall antibiotic resistance of H. pylori was high, and the relationship between drug resistance and cagA status was not statistically significant. Therefore, different treatment regimens are not recommended for patients with H. pyloricagA positive infections.

Primary antibiotic resistance and its relationship with cagA and vacA genes in Helicobacter pylori isolates from Algerian patients

“…The vac A s 1 m 1/ cag A+ genotype is associated with more severe gastric diseases due to the fact that strains with this genotype cause severe inflammation with increased production of IL-1β and TNF-α, inducing inhibitors of secretion of hydrochloric acid and increase gastric pH; conditions that may favor the action of antibiotics. 56 The metronidazole resistance had relation with the presence of cag A genotype in our study, this data disagree with those reported by Khan et al 57 where they found that the absence of cag A gene contributes in the acquisition of resistance. Apparently, infected patients with vac A s 1 m 1/ cag A+ resistant strains are at increased risk of progression to more severe conditions by failure in H. pylori eradication.…”

Comparative Evaluation of RUT, PCR and ELISA Tests for Detection of Infection with Cytotoxigenic H. pylori

“…12, 36 Hence, all the samples were screened for the presence of cag A gene by PCR using two pairs of specific primers related to C-terminus and N-terminus of the cag A protein. The results indicated that all but one patient were infected with cag A-positive strains.…”

Exploring the potential of Cinnamomum zeylanicum oil against drug resistant Helicobacter pylori-producing cytotoxic genes

“…Korona- Glowniak et al (2019) reported that cagA and vacAs1 genotypes were present in 75 and 62.5% of MDR H. pylori strains, respectively. Ghotaslou et al (2013a) found no link between antibiotic resistance and the cagA gene. Except for metronidazole, which had a significant relationship with the cagA gene, Bachir et al (2018) found no association between vacA or cagA genotypes and drug resistance.…”