The Controversies of the Relationship Between Helicobacter Pylori Infection and Inflammatory Bowel Disease: A Review

Background: The relationship between Helicobacter pylori (H. pylori) infection and inflammatory bowel disease (IBD) remains controversial. While H. pylori is a well-established pathogen in gastroduodenal diseases, emerging evidence suggests it may exert immunomodulatory effects that influence the pathogenesis and clinical course of IBD.Objective: This review aims to explore the association between H. pylori infection and IBD, focusing on infection prevalence among IBD patients, the potential protective or harmful roles of H. pylori, and the impact of eradication therapy on IBD onset and activity. Methods: A comprehensive literature search was conducted using PubMed up to May 25, 2025, including clinical studies, meta-analyses, systematic reviews, and observational data. A total of 40 studies met the inclusion criteria and were critically reviewed. Results: The majority of studies indicate a significantly lower prevalence of H. pylori infection among patients with IBD compared to the general population. Several meta-analyses support a potential protective effect, particularly in Crohn’s disease and among CagA-positive H. pylori strains. However, data on the impact of eradication therapy on IBD progression remain inconclusive. Some studies suggest a higher relapse risk post-eradication, while others report no change in disease activity. Variability in outcomes may be influenced by geographic, demographic, and methodological differences, as well as disease activity at the time of eradication. Conclusion: Although numerous studies support an inverse association between H. pylori infection and IBD, the nature and direction of this relationship remain unclear. Given the complex interplay between host immunity, gut microbiota, and antibiotic exposure, the decision to eradicate H. pylori in IBD patients should be individualized. Further prospective studies are needed to clarify the immunological and microbiological mechanisms underlying this association and to inform clinical guidelines.