Intestinal Microbiota in Hirschsprung Disease.

Area of Science:

• Gastroenterology
• Microbiology
• Pediatric Surgery

Background:

• Hirschsprung disease (HD) is a congenital disorder affecting the large intestine, often associated with gastrointestinal dysfunctions.
• Hirschsprung-associated enterocolitis (HAEC) is a severe complication of HD, with poorly understood underlying mechanisms.
• The gut microbiome's role in intestinal health and disease is increasingly recognized, particularly in pediatric conditions.

Purpose of the Study:

• To characterize the gut microbiota profiles in patients with Hirschsprung disease (HD).
• To evaluate the relationship between microbiota composition, postoperative bowel function, and the incidence of Hirschsprung-associated enterocolitis (HAEC).

Main Methods:

• Retrospective analysis of patients who underwent surgery for HD between 1987 and 2011.
• Collection of data through bowel function questionnaires and clinical follow-up.
• Fecal DNA extraction for microbiota profiling, fecal calprotectin (FC) measurement, and lactase (LCT) genotyping, compared with healthy controls.

Main Results:

• Patients with HD exhibited significantly decreased microbial richness and altered composition compared to healthy controls.
• A notable increase in Proteobacteria was observed in HD patients, suggesting a reduced carbohydrate degradation potential.
• While 77% of patients had a history of HAEC, no active HAEC or elevated FC was noted at sampling; genetic lactase deficiency was present in 17% without correlation to symptoms.

Conclusions:

• Patients with HD, particularly those with a history of HAEC, present a significantly altered intestinal microbiome characterized by reduced richness and specific bacterial expansions.
• The observed dysbiosis may be intrinsic to HD or a consequence of factors like antibiotic use.
• Further research is necessary to elucidate the causal relationship between the HD microbiome and disease progression or complications.