A 3-day-old neonate passes a large amount of mucus per rectum followed by no stool. Abdominal X-ray shows multiple dilated loops with air-fluid levels. A contrast enema demonstrates microcolon with reflux of contrast into the terminal ileum where multiple filling defects are seen. The diagnosis is:

• A Hirschsprung disease
• B Meconium ileus ✓
• C Meconium plug syndrome
• D Small left colon syndrome

Explanation

Meconium ileus presents with failure to pass meconium, microcolon (unused colon), and inspissated meconium pellets in the terminal ileum seen as filling defects on contrast enema. Meconium ileus is pathognomonic of cystic fibrosis in over 90 percent of cases. Hirschsprung disease shows a transition zone. Meconium plug syndrome shows normal-sized colon with plugs that often pass spontaneously. Small left colon syndrome is seen in infants of diabetic mothers.

Reference: Coran's Pediatric Surgery, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.