Overlap between irritable bowel syndrome and inflammatory bowel disease

Area of Science:

• Gastroenterology
• Immunology
• Microbiology

Background:

• Irritable bowel syndrome (IBS) is associated with increased colonic inflammatory cells, distinct from inflammatory bowel disease (IBD).
• This low-grade inflammation predominantly involves mast cells, especially in female IBS patients.
• Inflammation pathways include infection, stress, food allergy, and gut microbiota alterations.

Purpose of the Study:

• To investigate the characteristics and contributing factors of low-grade mucosal inflammation in IBS.
• To explore the relationship between gut permeability, visceral hypersensitivity, and post-infective IBS.
• To identify risk factors for post-infective IBS, including psychological and microbiological elements.

Main Methods:

• Analysis of colonic mucosal inflammatory cell profiles in IBS patients.
• Assessment of gut permeability in small and large bowels.
• Review of risk factors for post-infective IBS, encompassing local, microbiological, and psychological aspects.

Main Results:

• IBS mucosa exhibits inflammation quantitatively less than IBD, with a predominance of mast cells.
• Post-infectious IBS is characterized by low-grade inflammation and prolonged increases in gut permeability.
• Psychological factors like stress, anxiety, and depression are identified as risk factors for post-infective IBS.

Conclusions:

• Low-grade mucosal inflammation, particularly mast cell-driven, is a feature of IBS.
• Increased gut permeability and visceral hypersensitivity are linked to IBS, especially post-infective forms.
• Further large-scale trials are needed to validate therapeutic strategies targeting these inflammatory changes in IBS.