Evaluation of diagnostic factors used to refer children with constipation for rectal biopsies.

PURPOSE: Children with constipation and suspected Hirschsprung's disease are referred for rectal biopsy. Since this is an invasive procedure, appropriate indications should be applied to minimize the number of "unnecessary" biopsies. METHODS: We reviewed all constipated children who underwent a rectal biopsy to diagnose a possible Hirschsprung's disease at a tertiary referral hospital over a 6-year period (2013-2018). We registered clinical and demographic factors in these children and conducted correlation and multivariate regression analysis to evaluate the relation between these factors and a diagnosis of Hirschsprung's disease. RESULTS: We identified 225 children, aged 0-17 years. In total, Hirschsprung's disease was diagnosed in only 49/225 (22%). Among the 49 children with Hirschsprung's disease, 29 (59%) were diagnosed in the neonatal period. Among girls, HD was confirmed in only 10/101 (10%) children, and only 1 of these 10 girls was older than 6 months at the time of the biopsy. The following factors correlated significantly with Hirschsprung's disease diagnosis in children older than 1 month: "male sex", "failure to thrive", "gross abdominal distention plus vomiting" and "fulfils the Rome 4 criteria for functional constipation". CONCLUSION: In children referred for rectal biopsy, the factors most indicative of Hirschsprung's disease were "male sex", "failure to thrive", "gross abdominal distention plus vomiting" and "fulfils the Rome 4 criteria for functional constipation". Notably, the prevalence of Hirschsprung's disease decreased with the increasing age of the children. Girls referred for a biopsy rarely had Hirschsprung's disease, especially those older than 1 month.

"Too much guts and not enough brains": (epi)genetic mechanisms and future therapies of Hirschsprung disease - a review.

Hirschsprung disease is a neurocristopathy, characterized by aganglionosis in the distal bowel. It is caused by failure of the enteric nervous system progenitors to migrate, proliferate, and differentiate in the gut. Development of an enteric nervous system is a tightly regulated process. Both the neural crest cells and the surrounding environment are regulated by different genes, signaling pathways, and morphogens. For this process to be successful, the timing of gene expression is crucial. Hence, alterations in expression of genes specific for the enteric nervous system may contribute to the pathogenesis of Hirschsprung's disease. Several epigenetic mechanisms contribute to regulate gene expression, such as modifications of DNA and RNA, histone modifications, and microRNAs. Here, we review the current knowledge of epigenetic and epitranscriptomic regulation in the development of the enteric nervous system and its potential significance for the pathogenesis of Hirschsprung's disease. We also discuss possible future therapies and how targeting epigenetic and epitranscriptomic mechanisms may open new avenues for novel treatment.