Genotypic, phenotypic, and clinical characteristics of isolates ofHelicobacter pylori from San Luis, Argentina

ThevacA andcagA genotypes ofHelicobacter pylori exhibited distinct geographic distribution and correlation with severity of disease. In the above genotypes (obtained from 150H. pylori-positive patients — 139 with gastritis, 10 with ulcer and 1 patient with gastric cancer) combinationsvacA s1/m1 and s2/m2 were detected using PCR in 75 and 25% of isolates, respectively, in patients with chronic gastritis. The of s1/m1 and s2/m2 combinations were also detected from ulcers (60 and 40%, respectively). ThecagA was detected in 30% of isolates. Concentrated culture supernatants of 7 (64%) out of 11H. pylori strains induced vacuolization in Vero cells in titers ranging from 1 : 5 to 1 : 40. ThevacA s1 genotype was significantly associated with, but not predictive of the presence of vacuolating cytotoxin activity and thecagA gene.