Frequency of <it>vacA</it>, <it>cagA </it>and <it>babA2 </it>virulence markers in <it>Helicobacter pylori </it>strains isolated from Mexican patients with chronic gastritis

• Main Authors: Negrete Erasmo (Author), Camacho Ausencio (Author), Cortés José (Author), Rodríguez Cristina (Author), Arroniz Salvador (Author), Rodríguez Raymundo (Author), Monroy Eric (Author), Paniagua Gloria (Author), Vaca Sergio (Author)
• Format: Book
• Published: BMC, 2009-04-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.1186/1476-0711-8-14; 1476-0711
• Keywords: Therapeutics. Pharmacology; RM1-950; Infectious and parasitic diseases; RC109-216; Microbiology; QR1-502
• Source: Annals of Clinical Microbiology and Antimicrobials, Vol 8, Iss 1, p 14 (2009)

<p>Abstract</p> <p>Background</p> <p><it>Helicobacter pylori </it>has been strongly associated with chronic gastritis, peptic and duodenal ulcers, and it is a risk factor for gastric cancer. Three major virulence factors of <it>H. pylori </it>have been described: the vacuolating toxin (VacA), the cytotoxin-associated gene product (CagA) and the adhesion protein BabA2. Since considerable geographic diversity in the prevalence of <it>H. pylori </it>virulence factors has been reported, the aim of this work was to establish the <it>H. pylori </it>and <it>vacA</it>, <it>cagA </it>and <it>babA2 </it>gene status in 238 adult patients, from a marginal urban area of Mexico, with chronic gastritis.</p> <p>Methods</p> <p><it>H. pylori </it>was identified in cultures of gastric biopsies by nested PCR. <it>vacA </it>and <it>cagA </it>genes were detected by multiplex PCR, whereas babA2 gene was identified by conventional PCR.</p> <p>Results</p> <p><it>H. pylori</it>-positive biopsies were 143 (60.1%). All <it>H. pylori </it>strains were <it>vacA</it>⁺; 39.2% were <it>cagA</it>⁺; 13.3% were <it>cagA</it>⁺<it>babA2</it>⁺and 8.4% were <it>babA2</it>⁺. Mexican strains examined possessed the <it>vacA s1, m1 </it>(43.4%), <it>s1, m2 </it>(24.5%), <it>s2, m1 </it>(20.3%) and <it>s2, m2 </it>(11.9%) genotypes.</p> <p>Conclusion</p> <p>These results show that the Mexican patients suffering chronic gastritis we have studied had a high incidence of infection by <it>H. pylori</it>. Forty four percent (63/143) of the <it>H. pylori </it>strains analyzed in this work may be considered as highly virulent since they possessed two or three of the virulence markers analyzed: <it>vacA s1 cagA babA2 </it>(9.8%, 14/143), <it>vacA s1 babA2 </it>(4.9%, 7/143), and <it>vacA s1 cagA </it>(29.4%, 42/143). However, a statistically significant correlation was not observed between <it>vacAs1</it>, <it>cagA </it>and <it>babA2 </it>virulence markers (χ²test; P > 0.05).</p>