Professor Hazel Mitchell and colleagues from Australia conducted a comprehensive global systematic review and meta-analysis on the association between Helicobacter pylori infection and IBD.
As bacterial antigen cross-reactivity has been postulated to be involved in this association, published data on enterohepatic Helicobacter spp, and Campylobacter spp and IBD was also analyzed.
The team searched electronic databases up to 2015 for all case-control studies on H. pylori infection/enterohepatic Helicobacter spp/Campylobacter spp and IBD.
Analyses comprizing patients with Crohn's disease (CD), UC and IBD unclassified, showed a consistent negative association between gastric H. pylori infection and IBD.
|Antibiotics influenced the magnitude of this association|
The researchers found that this association appears to be stronger in patients with CD and IBD unclassified than UC.
Stratification by age, ethnicity and medications showed significant results.
The research team found that in contrast to gastric H. pylori, non H. pylori-enterohepatic Helicobacter spp, and Campylobacter spp, in particular C. concisus and C. showae, increase IBD risk.
Professor Mitchell's team concludes, "H. pylori infection is negatively associated with IBD regardless of ethnicity, age, H. pylori detection methods and previous use of aminosalicylates and corticosteroids."
"Antibiotics influenced the magnitude of this association."
"Closely related bacteria including enterohepatic Helicobacter spp and Campylobacter spp increase the risk of IBD."
"These results infer that H. pylori might exert an immunomodulatory effect in IBD."