MICROPRUNG : Intestinal Microbiota Analysis in Patients With or Without Hirschsprung's Associated EnteroColitis

Hirschsprung disease is a congenital abnormality due to the lack of migration of neural crest cells in myenteric and submucosal plexi of the bowel wall. The consequence is the absence of parasympathetic control of the distal bowel from the anal sphincter to various levels. The most common type of Hirschsprung disease alters the rectosigmoid (80%). The incidence is around 1/5000 live births. This anomaly requires a surgical ablation of the aganglionic segment.

Regardless of the surgical complications, patients with Hirschsprung disease are exposed to the risk of Hirschsprung Associated EnteroColitis (HAEC). This variable risk, 4-54%, is responsible to a major part of Hirschsprung disease morbimortality. Its onset is more frequent during the first two years of life and then decrease with age.

Its pathogenesis remains unclear but could be due to intestinal homeostasis breakdown that involves microbiota, intestinal barrier, immune system and enteric nervous system. This breakdown of the mutual benefit relation due to microbiota or bowel anomaly is known to be responsible of Crohn's disease onset. Some studies emphasize the role of microbiota in the pathogenesis of HAEC, but the techniques or the methodology with small numbers of patients limit any conclusion or clinical use.

The study hypothesizes microbiota is a major factor in HAEC onset and in their functional bowel problems. Considering HAEC is more frequent the first two years, it's thought that intestinal microbiota changes with time in those patients. This project is innovative because it will use high throughput sequencing methods and analysis for microbiome analysis on fecal samples from a multicenter cohort of patients at various ages.

Multicentre transversal study.

This study has the potential to significantly modify clinical practice for Hirschsprung disease patients: a better care for HAEC and functional troubles thanks to a better understanding of their microbiota, targetted antibiotic treatment for HAEC, prophylactic treatment of patients at high risk of HAEC.