Hirschsprung Disease Management
A 2-month-old boy has 5 days of no bowel motion, abdominal distension, and bilious vomiting. He first passed meconium on the fourth day of life and has needed suppositories since. Heart rate is 172 beats/min and capillary refill 3 seconds. Rectal examination produces an explosive gush of foul liquid stool. Radiography shows dilated bowel loops with no rectal gas. Which is the most appropriate next step in management?
- A.Empirical oral metronidazole for 7 days
- B.Prescription of oral lactulose twice daily
- C.Advice on a high fiber weaning diet
- D.Referral for surgical assessment and rectal biopsyCorrect
Explanation
This infant has Hirschsprung disease with a mechanical distal obstruction, and the correct action is urgent surgical referral rather than any medical treatment for constipation. Delayed passage of meconium beyond 48 hours, chronic obstructive symptoms, faltering growth, bilious vomiting, and the explosive decompression of stool after rectal examination together make the diagnosis, which is confirmed by rectal suction biopsy showing absent ganglion cells. Because the obstruction is anatomical and functional rather than dietary, laxatives and fiber cannot relieve it and may worsen distension and precipitate perforation. Initial management combines nasogastric decompression, intravenous fluids for the tachycardia and delayed capillary refill, rectal irrigations, and prompt surgical evaluation, with a leveling colostomy if the neonate is unstable. Definitive treatment is a pull-through procedure resecting the aganglionic segment and anastomosing ganglionated bowel to the anus, commonly a Swenson, Duhamel, or Soave operation, often performed once the child reaches a suitable weight. The most feared complication is Hirschsprung associated enterocolitis, which presents with fever, explosive foul stools, abdominal distension, and sepsis and requires broad spectrum intravenous antibiotics, decompression, and resuscitation, not an oral antibiotic course. Any infant with obstructive symptoms and a history of delayed meconium passage needs surgery, not laxatives.
Why each option
- A.
- Oral metronidazole is inadequate; suspected Hirschsprung associated enterocolitis needs intravenous broad spectrum antibiotics with decompression and resuscitation.
- B.
- Lactulose treats functional constipation and will worsen distension in an anatomically obstructed aganglionic bowel.
- C.
- Dietary fiber has no role in an obstructed 2-month-old who is not yet weaned and cannot overcome aganglionosis.
- D.
- Correct. Distal mechanical obstruction from Hirschsprung disease requires surgical evaluation with confirmatory rectal biopsy and definitive pull-through surgery.
Reference: Nelson Textbook of Pediatrics, 22nd ed., 2024
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