Helicobacter pylori cagA and vacA genes in dyspeptic Ghanaian patients

Abstract

Background: Helicobacter pylori infection is prevalent in Ghana. The development of gastro-duodenal disease is dependent on virulence of the infecting strain, host susceptibility and environmental factors. Helicobacter pylori cagA and vacA strains induce more inflammation, ulceration and oncogenesis. Here, for the first time we present data on H. pylori cagA and vacA genes and their association with gastro-duodenal disease in Ghana. A total of 159 patients with dyspepsia at Korle-Bu Teaching Hospital, Accra, were investigated for H. pylori with urease-CLO, of which 113 (71.1%) were positive. Genomic DNA was extracted from antral biopsies using QIAGEN DNeasy kit. Detection of H. pylori vacA and cagA genes were determined by PCR as previously described. Results: In total, 110 (69.2%) vacAs1, 71 (44.7%) vacAm1, 35 (22.0%) vacAm2, 77 (48.4%) cagA-(hydrophilic region) and 109 (68.6%) cagA-(internal duplication region) were detected. In multivariate analysis, duodenal ulcer was more likely than other diagnoses to have detectable cagA-(hydrophilic region) (OR 3.1 CI 1.2-7.9) or vacAs1m1 (OR 6.5 CI 1.2-34.0). Conclusions: Majority of biopsies were colonized with H. pylori harboring both cagA and vacA. H. pylori cagA-(internal duplication region) was more prevalent than cagA-(hydrophilic region). Duodenal ulcer was more likely than other diagnoses to have detectable cagA-(hydrophilic region) or vacAs1m1.