Microbiome Composition in Microscopic Colitis: A Systematic Review

Area of Science:

• Gastroenterology
• Microbiome Research
• Immunology

Background:

• Microscopic colitis (MC) is an increasingly diagnosed cause of chronic diarrhea.
• The pathogenesis of MC is not fully understood, necessitating research into its associated microbiota.
• Risk factors for MC are prevalent, further supporting the need for etiological studies.

Approach:

• A systematic review and meta-analysis of eight case-control studies was conducted.
• Literature search performed across PubMed, Scopus, Web of Science, and Embase databases.
• Risk of bias assessed using the Newcastle-Ottawa Scale.

Key Points:

• A consistent finding across studies was a reduction in the Akkermansia genus in fecal samples of MC patients.
• Inconsistencies in other taxonomic findings were noted, potentially due to varying analytical approaches and taxonomic resolutions.
• Alpha diversity analysis suggested potential similarities between MC and other diarrheal conditions, while beta diversity showed no significant differences compared to healthy or diarrheal populations.

Conclusions:

• While the microbiome composition in MC may differ from healthy individuals, there is no consensus on specific taxa involved.
• Further research should investigate factors influencing microbiome alterations in MC and their relationship with other diarrheal diseases.
• Standardized methodologies are needed for consistent microbiome profiling in MC research.