VacA genotyping directly from gastric biopsy specimens and estimation of mixed Helicobacter pylori infections in patients with duodenal ulcer and gastritis

Scand J Gastroenterol. 1999 Aug;34(8):743-9. doi: 10.1080/003655299750025651.

Abstract

Background: The vacA genotypes and the cagA gene status were investigated in 80 Helicobacter pylori-infected patients with duodenal ulcer (DU) and 49 with gastritis only.

Methods: Lysates of gastric biopsy specimens were used directly for polymerase chain reaction-based detection.

Results: The ml subtype was found in 36% and 31% and the m2 in 36% and 46% of specimens from patients with DU and gastritis, respectively (P > 0.05). In 15% of samples the midregion remained unclassified. The prevalence rate of s1 subtypes was higher in cases of DU (69%) than in gastritis (43%) (P < 0.0001); the opposite correlation was observed for s2. The cagA gene was detected in 80% of patients with DU and in 52% of those with gastritis (P < 0.0001). Infections with multiple H. pylori strains exceeded 50% in both groups.

Conclusions: These results suggest that vacA s1 genotype and cagA+ status are associated with higher DU prevalence and that mixed H. pylori infections are very common in our geographic region.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Bacterial*
  • Bacterial Proteins / genetics*
  • Biopsy
  • Duodenal Ulcer / microbiology*
  • Duodenal Ulcer / pathology
  • Gastric Mucosa / pathology
  • Gastritis / microbiology*
  • Gastritis / pathology
  • Genotype
  • Helicobacter Infections / microbiology*
  • Helicobacter Infections / pathology
  • Helicobacter pylori / genetics*
  • Humans
  • Polymerase Chain Reaction
  • Statistics, Nonparametric

Substances

  • Antigens, Bacterial
  • Bacterial Proteins
  • VacA protein, Helicobacter pylori
  • cagA protein, Helicobacter pylori