Prevalence of Helicobacter pylori cagA, iceA and babA2 alleles in Brazilian patients with upper gastrointestinal diseases.
Helicobacter pylori is an important human pathogen associated with gastrointestinal diseases such as gastritis, gastric and duodenal ulcer (peptic ulcer disease, PUD), and gastric cancer. A number of pathogenic factors have been described for this bacterium, and some of them have been proposed as markers for the prediction of the clinical outcome. However, with the exception of the cag and vacA status, there is no universal consensus regarding the importance of the other virulence factors. Therefore, the aim of this study was to investigate the status of H. pylori strains regarding the babA and iceA alleles, as well as the cagA genotype, to reveal any association between these genotypes and clinical outcomes in Brazilian patients. The great majority (92.6%) of the strains were typed as iceA1, while 40.4% were found to possess the babA2 allele. The cagA gene was detected in 73.4% of the strains. The iceA2 and cagA genotypes were associated with PUD, while iceA1 was negatively correlated with PUD. However, considering the high percentage of strains typed as iceA1, these associations must be treated with caution. No clinical entity was associated with the babA2 allele. These results suggest that iceA1 is not a good marker for the diseases associated with H. pylori infection in Brazil. Further studies are needed in order to elucidate the relevance of the babA status, because other studies performed in Brazil have associated the babA2 allele with clinical outcomes. These results also indicate the existence of regional differences in the H. pylori genotypes and their association with clinical outcomes.
Gatti
Luciano Lobo
LL
Laboratório de Genética e Biologia Molecular, Faculdade de Medicina de Marília (FAMEMA), Brazil. lobogatti@yahoo.com.br
Módena
José Luiz Proença
JL
Payão
Spencer Luiz Marques
SL
Smith
Marília de Arruda Cardoso
Mde A
Fukuhara
Yara
Y
Módena
José Luiz Pimenta
JL
de Oliveira
Ricardo Brandt
RB
Brocchi
Marcelo
M
D018829:Adhesins, Bacterial / Q000235:genetics*; D000483:Alleles; D000942:Antigens, Bacterial / Q000235:genetics*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D001706:Biopsy; D001938:Brazil; D005260:Female; D005767:Gastrointestinal Diseases / Q000209:etiology* / Q000473:pathology; D041981:Gastrointestinal Tract / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000472:pathogenicity; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D014774:Virulence / Q000235:genetics
D018829:Adhesins, Bacterial; D000942:Antigens, Bacterial; C400429:BabA protein, Helicobacter pylori; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori; C063113:ice nucleation protein