Patients with anorectal malformation and Hirschsprung's disease

Dysganglionosis and aganglionosis have been frequently described in biopsies of the distal bowel in patients with anorectal malformation (ARM). They are interpreted as a developmental disorder of the anorectum. The true association of total colonic aganglionosis and anorectal malformation has not been reported before. The aim of this study was to explore the true association of anorectal malformation and Hirschsprung's disease with or without trisomy 21.

A retrospective study of all patients diagnosed with anorectal malformation in our institute from 1986-2008 was performed. All patients with anorectal malformation and Hirschsprung's disease were included in the study. Rectal biopsies were taken from multiple sites, including the rectum, left, transverse, right colon and appendix. The diagnosis of aganglionosis was proven histopathologically by the absence of ganglion cells with or without acetylcholinesterase staining. Specimens were examined by at least two experienced consultant pathologists.

Aganglionosis was confirmed in three patients out of 53 patients with anorectal malformation. Two had Down's syndrome. All were males and presented with high anorectal malformation without fistula. The clinical presentation was intestinal obstruction, necrotizing enterocolitis and failure to thrive. The level of aganglionosis was up to the left colon in two and total colonic with ileal involvement in one. One of the children with Down's syndrome and total colonic aganglionosis died. Another had correction of a congenital heart disease, colostomy and is awaiting definitive surgery. The third case is continent at the age of 22 years with a Malone stoma after pull-through of ARM and a subsequent Duhamel procedure.

The association between ARM and intestinal dysganglionosis is not rare. We recommend not using the distal rectal pouch and parts of the fistula in the reconstruction of anorectal malformations as this may solve the constipation if the pathology is limited. In cases of aganglionosis beyond the rectal pouch and fistula, surgical intervention is needed. Delay in diagnosis may lead to morbidity or even mortality.