Paediatrics: Hirschsprung’s disease

Hirschsprung’s disease

The incidence of HSD is 1/5000 live births. It may be familial and associated with trisomy 21.

•   It is caused by a failure of ganglion cells to migrate into the hindgut.

•   This defect leads to an absence of co-ordinated bowel peristalsis and functional intestinal obstruction at the junction (‘transition zone’) between normal bowel and the distal aganglionic bowel.

•   In 80% of cases the transition zone is in the rectum or sigmoid—short segment disease.

•   In 20% of cases the entire colon is involved—long segment disease.

•   Occasionally, children with short segment disease present in childhood with chronic constipation.

Diagnosis

•   Usually presents within the first few days of life with low intestinal obstruction, i.e. failure to pass meconium, abdominal distension, and bile-stained vomiting. 99% of normal newborns pass meconium within 24hr of delivery.

•   AXR: distal intestinal obstruction.

•   Rectal biopsy: no ganglion cells in the submucosa.

Surgical treatment

Many surgeons now perform a single stage pull-through in the neonatal period, managing initial intestinal obstruction with rectal washouts, but traditionally a 3-stage procedure is used.

•   Defunctioning colostomy, with multiple biopsies to confirm the site of the transition zone.

•   Pull-through procedure to bring ganglionic bowel down to the anus.

•   Closure of colostomy.

Outcome

•   The long-term results are generally satisfactory with approximately 75% of children acquiring normal bowel control, 15–20% partial control, and 5% who never gain control and may end up with a permanent stoma.

Most important complication of HSD is enterocolitis. A dramatic gastroenteritic illness characterized by abdominal distension, bloody watery diarrhoea, circulatory collapse, and septicaemia. Condition usually associated with Clostridium difficile toxin in the stools. Mortality 710%.