title: Multiple cag genotypes of Helicobacter pylori isolates colonize the oesophagus in individual hosts in a Venezuelan population.
abstract: OBJECTIVE
  Multiple Helicobacter pylori strains colonize and coexist in the stomach of one single patient, carrying heterogeneous distributions of cag genotypes. The oesophagus provides a niche for H. pylori colonization; however, little is known about its adaptive role.
  
  
  METHODS
  Using PCR for cagA, cagE and virB11 genes from cag-pathogenicity island (PAI) and Etest for antimicrobial susceptibility test, we determined cag-PAI genotypes associated with H. pylori virulence, when positive cultures were matching in both the stomach and the oesophagus (96 isolates; 8 out of 80 dyspeptic patients).
  
  
  RESULTS
  The stomach showed complete cag-PAI islands in 77 % of the isolates, whereas the oesophagus showed complete cag-PAI islands only in 44 % of the isolates. Expression of CagA and interleukin 8 correlated with inflammatory processes and histopathological changes in the stomach, but not in the oesophagus. Different cag-PAI profiles were found in both mucosae of an individual host, and at least one oesophagus profile corresponded to one profile identified in stomach. The antibiotic resistance profiles showed variability in the colonization by single or mixed H. pylori isolates in the gastric and oesophageal mucosa both intra- and inter-individuals.
  
  
  CONCLUSIONS
  These results demonstrate colonization with multiple H. pylori isolates in the oesophageal mucosa, like those found in the stomach of individual hosts. H. pylori was characterized by a dominant partial island, low interleukin 8 induction with lower histopathological damage and lower antibiotic resistance, suggesting that the microenvironmental changes in individual hosts select less virulent isolates in the oesophagus than in the stomach. New approaches to ensure effective eradication therapy in multi-resistant H. pylori strains must be developed.
authors.affiliation: Laboratorio de Fisiología Gastrointestinal, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
authors.forename: Jessy
authors.initials: J
authors.lastname: Peña
authors.affiliation: Instituto de Inmunología, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela.|Laboratorio de Fisiología Celular, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
authors.forename: Héctor
authors.initials: H
authors.lastname: Rojas
authors.affiliation: Laboratorio de Fisiología Gastrointestinal, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
authors.forename: Nelson
authors.initials: N
authors.lastname: Reyes
authors.affiliation: Laboratorio de Fisiología Gastrointestinal, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
authors.forename: Milagro
authors.initials: M
authors.lastname: Fernández-Delgado
authors.affiliation: Laboratorio de Fisiología Gastrointestinal, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
authors.forename: María-Alexandra
authors.initials: MA
authors.lastname: García-Amado
authors.affiliation: Laboratorio de Fisiología Gastrointestinal, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
authors.forename: Fabián
authors.initials: F
authors.lastname: Michelangeli
authors.affiliation: Laboratorio de Fisiología Gastrointestinal, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Miranda, Venezuela.
authors.forename: Monica
authors.initials: M
authors.lastname: Contreras
mesh_terms: D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D004947:Esophagus / Q000382:microbiology*; D005260:Female; D044404:Genomic Islands; D005838:Genotype; D060005:Genotyping Techniques; D016481:Helicobacter Infections / Q000175:diagnosis / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics*; D054884:Host-Pathogen Interactions; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D014687:Venezuela
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C508606:CXCL8 protein, human; D004269:DNA, Bacterial; D016209:Interleukin-8; C103937:PicB protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori