A 2-day-old neonate is found to have abdominal distension and failure to pass meconium. Plain X-ray shows a 'soap bubble' appearance in the right iliac fossa. What is the MOST likely diagnosis?

• A Hirschsprung's disease
• B Necrotising enterocolitis
• C Jejunal atresia
• D Meconium ileus ✓

Explanation

The 'soap bubble' or 'ground glass' appearance on plain X-ray in the right iliac fossa of a neonate with intestinal obstruction and failure to pass meconium is pathognomonic of meconium ileus — caused by inspissated meconium obstructing the terminal ileum, typically in cystic fibrosis (present in ~90% of cases). Hirschsprung's disease typically shows dilated proximal colon with a narrow segment and is confirmed by rectal biopsy. Jejunal atresia shows a 'triple bubble' or multiple air-fluid levels. NEC predominantly affects premature neonates and shows pneumatosis intestinalis.

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.