Professor Hazel Mitchell and colleagues 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 Helicobacter pylori infection/enterohepatic Helicobacter spp/Campylobacter spp and IBD.
Analyses comprizing patients with Crohn's disease, ulcerative colitis and IBD unclassified, showed a consistent negative association between gastric Helicobacter pylori infection and IBD.
|Helicobacter pylori might exert an immunomodulatory effect in IBD|
The researchers noted that this association appears to be stronger in patients with Crohn's disease, and IBD unclassified than ulcerative colitis.
The team showed significant results after stratification by age, ethnicity and medications.
In contrast to gastric Helicobacter pylori, non Helicobacter pylori-enterohepatic Helicobacter spp and Campylobacter spp, in particular C. concisus and C. showae, increase IBD risk.
Professor Mitchell's team comments, "Helicobacter pylori infection is negatively associated with IBD regardless of ethnicity, age, Helicobacter 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 Helicobacter pylori might exert an immunomodulatory effect in IBD."