First Insights into the Gut Microbiota of Mexican Patients with Celiac Disease and Non-Celiac Gluten Sensitivity

Gluten-related disorders (GRDs) are common chronic enteropathies and increasing evidence suggests an involvement of the gut microbiota. We examined the gut microbiota in Mexican people afflicted with GRDs. Ultra-high-throughput 16S marker sequencing was used to deeply describe the duodenal and fecal microbiota of patients with celiac disease (CD, n = 6), non-celiac gluten sensitivity (NCGS, n = 12), and healthy subjects (n = 12) from our local area. Additionally, we also investigated the changes in gut microbiota after four weeks on a gluten-free diet (GFD) in a subset of patients from whom paired samples were available. Despite a high inter-individual variability, significant differences in various microbial populations were identified. The linear discriminant analysis (LDA) effect size (LEfSe) method revealed that the genus Actinobacillus and the family Ruminococcaceae were higher in the duodenal and fecal microbiota of NCGS patients, respectively, while Novispirillum was higher in the duodenum of CD patients (p < 0.05, LDA score > 3.5). Interestingly, paired samples from NCGS patients showed a significant difference in duodenal Pseudomonas between the baseline period (median: 1.3%; min/max: 0.47-6.8%) and the period after four weeks on GFD (14.8%; 2.3-38.5%, p < 0.01, Wilcoxon signed-rank test). These results encourage more research on GRDs in Mexico.