Hirschsprung Disease Overview – RETIRED CHAPTER, FOR HISTORICAL REFERENCE ONLY

NOTE: THIS PUBLICATION HAS BEEN RETIRED. THIS ARCHIVAL VERSION IS FOR HISTORICAL REFERENCE ONLY, AND THE INFORMATION MAY BE OUT OF DATE.

Clinical characteristics: Hirschsprung disease (HSCR), or congenital intestinal aganglionosis, is a birth defect characterized by complete absence of neuronal ganglion cells from a portion of the intestinal tract. The aganglionic segment includes the distal rectum and a variable length of contiguous proximal intestine. In 80% of individuals, aganglionosis is restricted to the rectosigmoid colon (short-segment disease); in 15%-20%, aganglionosis extends proximal to the sigmoid colon (long-segment disease); in about 5%, aganglionosis affects the entire large intestine (total colonic aganglionosis). Rarely, the aganglionosis extends into the small bowel or even more proximally to encompass the entire bowel (total intestinal aganglionosis). HSCR is considered a neurocristopathy, a disorder of cells and tissues derived from the neural crest, and may occur as an isolated finding or as part of a multisystem disorder. Affected infants frequently present in the first two months of life with symptoms of impaired intestinal motility such as failure to pass meconium within the first 48 hours of life, constipation, emesis, abdominal pain or distention, and occasionally diarrhea. However, because the initial diagnosis of HSCR may be delayed until late childhood or adulthood, HSCR should be considered in anyone with lifelong severe constipation. Individuals with HSCR are at risk for enterocolitis and/or potentially lethal intestinal perforation.

Diagnosis/testing: The diagnosis of HSCR requires histopathologic demonstration of absence of enteric ganglion cells in the distal rectum. Suction biopsies of rectal mucosa and submucosa are the preferred diagnostic test in most centers because they can be performed safely without general anesthesia. Syndromes associated with HSCR are diagnosed by clinical findings, cytogenetic analysis, or in some cases, by specific molecular or biochemical tests. Isolated HSCR (i.e., HSCR in the absence of related systemic findings) is a disorder associated with pathogenic variants in a number of genes.

Genetic counseling: Recurrence risk depends on the underlying cause.

Management: Treatment of manifestations: Resection of the aganglionic segment and anastomosis of proximal bowel to the anus ("pull-through") is the standard treatment for HSCR. Individuals with extensive intestinal aganglionosis who develop irreversible intestinal failure may be candidates for intestinal transplantation.