Variations in gut microbiota in celiac disease patients: a systematic review.

Aim: This review aims to summarize the characteristics of gut microbiota in celiac patients and assess its composition compared to healthy controls.

Background: The gut microbiota influences the regulation of host immunity. Accordingly, alterations in the intestinal microbiota, also known as dysbiosis, have been studied in various gastrointestinal disorders, including celiac disease.

Methods: We conducted a systematic review of available studies over the last decade (2013-2023). The comprehensive search was performed using various academic databases. The selected studies focused on the analysis of gut microbiota from duodenal and/or fecal samples and included both pediatric and adult populations.

Results: Twenty-two articles were included following PRISMA guidelines: nine on fecal microbiota, six on duodenal microbiota, and seven on both. The findings revealed significant differences in bacterial prevalence associated with celiac disease across 17 studies, with celiac patients showing altered microbial diversity characterized by an increase in pathogenic bacteria and a decrease in beneficial bacteria such as Bifidobacterium and Lactobacillus, compared to healthy controls. However, other studies showed no significant distinction between groups of children affected by celiac disease and control groups. Some articles also highlight the effect of a gluten-free diet on the composition of the gut microbiota.

Conclusion: Current data on the composition of the gut microbiome in patients with celiac disease is characterized by considerable heterogeneity and inconsistency. This highlights the need for a thorough and holistic approach to understand better these variations and their impact on the health of people with celiac disease.