Prevalence, antibiotic resistance and molecular characterization of virulence factors of Helicobacter pylori strains isolated from patients with dyspepsia.

Abstract

Helicobacter pylori is a major pathogen infecting over half of the global population, causing conditions like gastritis, ulcers, gastric cancer, and lymphoid tissue lymphoma. This study investigated the prevalence of H. pylori in 100 gastric biopsy samples from patients with dyspepsia and analyzed antibiotic resistance and virulence genes (cagA, vacA, iceA, and babA) using polymerase chain reaction (PCR). Diagnosis was performed via PCR, culture, rapid urease test, and histopathological examination, with antibiotic susceptibility assessed through the E-test method.The study was conducted between September 2022 and February 2023. The study found that 34% of samples were PCR-positive for H. pylori, while culture, histology examination, and rapid urease test showed positivity rates of 23%, 53%, and 63%, respectively. Alarmingly, antibiotic resistance was prevalent, with 100% resistance to clarithromycin and metronidazole, 39.1% to tetracycline, and 34.8% to levofloxacin. Virulence gene analysis revealed high positivity rates: cagA (53%), babA (29%), iceA1 (20.6%), iceA2 (41.2%), and vacA (97.1%), with the vacA s1m2 allele variant being most common (55.8%).These findings underscore the significant role of virulence factors like cagA and vacA in H. pylori pathogenesis and the severity of related diseases. The study highlights the urgent need for routine antimicrobial susceptibility testing to guide treatment amidst escalating antibiotic resistance. It also emphasizes the value of molecular diagnostics, such as PCR, for accurate and rapid detection of H. pylori and its virulence determinants. These insights are critical for improving the management of H. pylori-associated diseases and combating antibiotic resistance globally.