Prevalence of cagA and vacA genes in isolates from patients with Helicobacter pylori-associated gastroduodenal diseases in Recife, Pernambuco, Brazil

Memórias do Instituto Oswaldo Cruz

Carlos Aa Brito²  Lenôra Mb Silva²  Norma Jucá¹  Nilma C Leal²  Wayner De Souza²  Dulciene Queiroz¹  Francisco Cordeiro¹  Norma Lucena Silva² 

[1] ,Fundação Oswaldo Cruz Centro de Pesquisas Aggeu Magalhães Departamento de ImunologiaRecife PE ,Brazil

关键词: cagA;    vacA;    genotype;    Helicobacter pylori;    Recife;    Brazil;   

DOI  :  10.1590/S0074-02762003000600018

来源: SciELO

【 摘 要 】

Geographical differences in the prevalence of Helicobacter pylori genes and their association with disease severity have been identified. This study analyzes the prevalences of the cagA gene and alleles of the vacA gene in H. pylori-associated gastroduodenal diseases in isolates from Recife, PE, Brazil. Gastric biopsy of 61 H. pylori-positive patients were submitted to DNA extraction and gene amplification by polymerase chain reaction. Among the 61 patients, 21 suffered from duodenal ulcer (DU) and 40 from gastritis (GT). The prevalence of H. pylori strains harbouring the cagA gene was higher in the DU group (90.5%) than in the GT group (60%) (p = 0.02). The vacA gene was amplified in 56 out of 61 biopsies, of which 43 (76.8%) contained bacteria carrying the s1 allele and 13 (23.2%) the s2. However, the prevalence of the vacA s1 genotying was the same in either DU or GT group. The majority of the s1-typed strains, 39 (90.7%) out of 43, were subtype s1b. In resume there was a strong association between the H. pylori cagA+ gene and DU. However, there were no differences between the DU and GT groups in relation to the vacA s1 and s2 alleles distribution, albeit the subtype s1b was predominat.

【 授权许可】

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