Barrett's esophagus and gastro-esophageal reflux disease (GERD) are precursors of esophageal adenocarcinoma.
There is an esophageal biofilm, which changes in disease, but its role in aetiopathogenesis remains unclear.
Dr Dillon and colleagues from the United Kingdom defined the esophageal microbiota of patients with GERD, Barrett's esophagus and esophageal adenocarcinoma compared with controls, and investigated mucosal responses related to the microbiota.
Cultural analysis identified the dominant bacterial species from a subset of each disease group.
Based on this, molecular techniques were used to define the cohort.
|Campylobacter concisus was the dominant species|
|Alimentary Pharmacology & Therapeutics|
The research team analyzed host responses in tissues and co-culture experiments.
A total of 111 species belonging to 26 genera were isolated.
The team found a significant decrease in bacterial counts in the GERD and Barrett's esophagus groups for all genera except Campylobacter, which colonized GERD and Barrett's patients in increasing numbers.
Campylobacter concisus was the dominant species.
The team did not observe this relationship in the cancer group.
Significant increases in IL-18 were seen in GERD and Barrett's esophagus colonized by Campylobacter.
Dr Dillon's team concludes, "This study defines differences in the esophageal biofilm in disease states, revealing the emergence of C. concisus as the dominant new colonist in the refluxed esophagus."
"We also associate the presence of these bacteria with increased expression of cytokines related to carcinogenesis."