A 2-day-old neonate has failed to pass meconium, with abdominal distension and bilious vomiting. Suction rectal biopsy shows absence of ganglion cells in the submucosal (Meissner's) and myenteric (Auerbach's) plexuses with hypertrophied nerve trunks. The diagnosis is Hirschsprung disease. What determines the extent of surgical resection?

• A Length of the distended bowel segment on contrast enema
• B Extent of the aganglionic segment confirmed by intraoperative frozen section biopsies to identify the transition zone ✓
• C Age of the patient; short-segment disease in neonates never requires surgery
• D The level of obstruction seen on plain abdominal X-ray

Explanation

In Hirschsprung disease, the extent of the aganglionic segment (recto-sigmoid most common, but may extend to total colonic aganglionosis) determines the required resection extent. Intraoperative frozen section biopsies at multiple levels confirm the presence of normal ganglion cells at the proximal resection margin before pull-through anastomosis. The transition zone (area between normal and aganglionic bowel) can be unreliable on contrast enema and must not be used alone to define the extent of resection.

Reference: Bailey & Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.