Helicobacter pylori vacA and cagA genotypes in patients from northeastern Brazil with upper gastrointestinal diseases.
Helicobacter pylori causes chronic gastric inflammation and significantly increases the risk of duodenal and gastric ulcer disease and distal gastric carcinoma. In this study, we evaluated the Helicobacter pylori vacA and cagA genotypes in patients from a Brazilian region where there is a high prevalence of gastric cancer. Polymerase chain reaction (PCR) was used to investigate vacA mosaicism and cagA status in the gastric mucosa of 134 H. pylori-positive patients, including 76 with gastritis: 28 with peptic ulcer disease and 30 with gastric cancer. The s1m1 variant was the predominant vacA genotype observed, whereas the s1 allele was more frequently observed in patients with more severe diseases associated with H. pylori infection [p = 0.03, odds ratio (OR) = 5.72, 95% confidence interval (CI) = 1.15-38.60]. Furthermore, all of the s1 alleles were s1b. Mixed vacA m1/m2 strains were found more frequently in patients with gastric cancer and a cagA-positive status was significantly associated with gastric cancer (p = 0.016, OR = 10.36, 95% CI = 1.35-217.31). Patients with gastric cancer (21/21, 100%, p = 0.006) or peptic ulcers (20/21, 95%, p = 0.02) were more frequently colonised by more virulent H. pylori strains compared to gastritis patients (41/61, 67.2%). In conclusion, in the northeastern of Brazil, which is one of the regions with the highest prevalence of gastric cancer in the country, infection with the most virulent H. pylori strains, carrying the cagA gene and s1m1 vacA alleles, predominates and is correlated with more severe H. pylori-associated diseases.
Unidade de Pesquisas Clínicas, Universidade Federal do Ceará, Fortaleza, CE, Brazil.
Meyssa Quezado de Figueiredo
MQ
Cavalcante
Cicero Igor Simões
CI
Silva
Manuel Bonfim
MB
Braga-Neto
Andréa Bessa Campelo
AB
Fialho
André
A
Nunes Fialho
Alzira Maria C
AM
Barbosa
Francisco Will Saraiva
FW
Cruz
Gifone A
GA
Rocha
Dulciene Maria Magalhães de
DM
Queiroz
Lucia Libanez Bessa Campelo
LL
Braga
D000328:Adult; D000942:Antigens, Bacterial / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D001938:Brazil; D005260:Female; D005756:Gastritis / Q000382:microbiology; D005838:Genotype; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000382:microbiology; D016133:Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000382:microbiology
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori