title: HELICOBACTER PYLORI INFECTION IN PATIENTS WITH DIFFERENT GASTROINTESTINAL DISEASES FROM NORTHERN BRAZIL.
abstract: BACKGROUND
  The mechanisms whereby Helicobacter pylori produces different pathological manifestations in the stomach and duodenum are not fully understood. Considering the geographic diversity in the prevalence of virulence factors of this microorganism and their association with the development of different diseases, the search for pathogenicity markers such as CagA and VacA alleles by molecular techniques has intensified.
  
  
  OBJECTIVE
  To investigate the presence of H. pylori infection and the frequency of different genotypes of this bacterium in patients with gastrointestinal diseases from Northern Brazil, and to establish their association with the histopathological findings.
  
  
  METHODS
  In a prospective study, samples were collected from 554 patients with different gastrointestinal diseases (gastritis, duodenal ulcer, gastric ulcer, and gastric cancer) seen at a referral hospital attending the entire State of Pará, located in the metropolitan region of Belém. Data such as gender and age obtained with an epidemiological questionnaire were analyzed. The presence of H. pylori and the bacterial genotype were investigated by PCR. Gastric biopsies were assessed histologically.
  
  
  RESULTS
  The prevalence of H. pylori infection was 91%. Infection was more frequent among patients with gastric ulcer and gastric cancer. In these groups, there was a predominance of men and older patients when compared to the other two groups studied. The predominant bacterial genotype was s1m1cagA+, which was more frequent among patients with gastric ulcer, duodenal ulcer and gastric cancer. A significant association was observed between s1m1cagA+ strains and a higher degree of inflammation, neutrophil activity and development of intestinal metaplasia.
  
  
  CONCLUSIONS
  The present study demonstrates a high incidence of H. pylori infection in the patients analyzed, especially among those with gastric ulcer and gastric cancer. Virulent s1m1cagA+ strains predominated and were associated with more severe lesions.
authors: Universidade Federal do Pará, Belém, PA, Brasil.
authors: Igor Dias Ferreira
authors: ID
authors: Vinagre
authors: Universidade Federal do Pará, Belém, PA, Brasil.
authors: André Lima de
authors: AL
authors: Queiroz
authors: Departamento de Gastroenterologia, Hospital Santo Antonio Maria Zaccaria, Bragança, PA, Brasil.
authors: Mário Ribeiro da
authors: MR
authors: Silva Júnior
authors: Departamento de Clínica Médica, Hospital Ofir Loiola, Belém, PA, Brasil.
authors: Ruth Maria Dias Ferreira
authors: RM
authors: Vinagre
authors: Universidade Federal do Pará, Belém, PA, Brasil.
authors: Luisa Caricio
authors: LC
authors: Martins
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D001938:Brazil; D005260:Female; D005767:Gastrointestinal Diseases / Q000382:microbiology*; D005838:Genotype; D016481:Helicobacter Infections / Q000175:diagnosis / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori