title: Bacterial biota in reflux esophagitis and Barrett's esophagus.
abstract: OBJECTIVE
  To identify the bacterial flora in conditions such as Barrettos esophagus and reflux esophagitis to determine if they are similar to normal esophageal flora.
  
  
  METHODS
  Using broad-range 16S rDNA PCR, esophageal biopsies were examined from 24 patients [9 with normal esophageal mucosa, 12 with gastroesophageal reflux disease (GERD), and 3 with Barrettos esophagus]. Two separate broad-range PCR reactions were performed for each patient, and the resulting products were cloned. In one patient with Barrettos esophagus, 99 PCR clones were analyzed.
  
  
  RESULTS
  Two separate clones were recovered from each patient (total = 48), representing 24 different species, with 14 species homologous to known bacteria, 5 homologous to unidentified bacteria, and 5 were not homologous (<97% identity) to any known bacterial 16S rDNA sequences. Seventeen species were found in the reflux esophagitis patients, 5 in the Barrettos esophagus patients, and 10 in normal esophagus patients. Further analysis concentrating on a single biopsy from an individual with Barrettos esophagus revealed the presence of 21 distinct bacterial species. Members of four phyla were represented, including Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria. Microscopic examination of each biopsy demonstrated bacteria in intimate association with the distal esophageal epithelium, suggesting that the presence of these bacteria is not transitory.
  
  
  CONCLUSIONS
  These findings provide evidence for a complex, residential bacterial population in esophageal reflux-related disorders. While much of this biota is present in the normal esophagus, more detailed comparisons may help identify potential disease associations.
authors.affiliation: Department of Pathology, New York University School of Medicine, New York, NY 10016, USA. zhiheng.pei@med.nyu.edu
authors.forename: Zhiheng
authors.initials: Z
authors.lastname: Pei
authors.forename: Liying
authors.initials: L
authors.lastname: Yang
authors.forename: Richard M
authors.initials: RM
authors.lastname: Peek
authors.forename: Steven M
authors.initials: SM
authors.lastname: Jr Levine
authors.forename: David T
authors.initials: DT
authors.lastname: Pride
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Blaser
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D001471:Barrett Esophagus / Q000382:microbiology*; D001483:Base Sequence; D016022:Case-Control Studies; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D004942:Esophagitis, Peptic / Q000382:microbiology*; D004947:Esophagus / Q000382:microbiology; D006801:Humans; D008875:Middle Aged; D010802:Phylogeny
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal