Key clinical point: A novel microbial signature distinguished children with celiac disease from healthy controls.
Major finding: Eleven operational taxonomic units (OTUs) were less abundant in fecal samples from children with treated and untreated celiac disease than in healthy controls. The microbial signature was diagnostic for celiac disease with an error rate of 21.5% (P < .001 compared with random classification).
Study details: Gas chromatography and 16S ribosomal RNA sequencing of fecal samples from 141 children: 20 with new-onset celiac disease, 45 with an established diagnosis who were on a gluten-free diet, 19 unaffected siblings, and 57 healthy children. Also, a prospective study of fecal samples from 13 newly diagnosed children after 6 and 12 months on a gluten-free diet.
Disclosures: Nutricia Research Foundation, the Biotechnology and Biological Sciences Research Council, and The Catherine McEwan Foundation provided funding. Three coinvestigators disclosed ties to Nutricia, 4D Pharma, Abbvie, Janssen, Takeda, Celltrion, and several other pharmaceutical companies. One coinvestigator reported chairing the working group for ISLI Europe. The remaining investigators reported having no conflicts of interest.
Zafeiropoulou K et al. Gastroenterology. 2020 Aug 10;S0016-5085(20)35023-X. doi: 10.1053/j.gastro.2020.08.007.
It is well known that gluten ingestion in genetically susceptible individuals does not guarantee celiac disease, and research over the past decade has searched for environmental triggers. Gut microbiota play a role in activation of innate immunity, which leads to the adaptive immune response and the small bowel damage that is characteristic of celiac disease. The authors of this study sought to identify whether there is a distinct microbial pattern among celiac disease patients, both those with treated and untreated disease, in comparison with healthy controls and healthy siblings.
The authors identified three groups of bacterial taxa: 1) unique to celiac disease independent of treatment, 2) new-onset disease and treatment responsive, and 3) reflective of diet changes and not unique to disease. Within the first group, 11 distinct operational taxonomic units (OTUs) could highly predict celiac disease regardless of treatment. From these results, we cannot determine if the microbial signature is a result of disease or a contributor to disease development; however, it reinforces that this unique signature is present at diagnosis and identifies taxa for further investigation.
A significantly different microbial profile and metabolites were identified in subjects on gluten-free diets. The consequences of the gluten-free diet are an important consideration when committing a patient to this life-long therapy. The microbiome changes may play a role in persistent symptoms and the increased health conditions we see in treated celiac disease. Those on a gluten-free diet have other micronutrient deficiencies in addition to microbiome changes and the health sequelae of this are not fully understood. A gluten-free diet focused on restoring the normal gut flora through probiotic or gluten-free prebiotic or fiber supplementation in celiac disease patients could prove beneficial.
Dawn Wiese Adams, MD, MS, is assistant professor and medical director, Center for Human Nutrition, department of gastroenterology, hepatology, and nutrition, Vanderbilt University Medical Center, Nashville, Tenn. She has no conflicts of interest.