✅ Model Answer:
• Findings: Midline, central abdominal wall defect with membranous sac (amnion and peritoneum) covering herniated viscera (bowel and liver). Umbilical cord inserts into sac.
• Diagnosis: Exomphalos (omphalocele).
• Difference from gastroschisis: Omphalocele – sac, midline, cord inserts into sac, associated anomalies common; Gastroschisis – no sac, right-sided, normal cord insertion.

✅ Model Answer:
• Failure of lateral body wall folds to close during 4th-5th week of gestation → herniation through umbilical ring.
• Midgut normally herniates into umbilical cord (physiological herniation) at 6-8 weeks and returns by 10-12 weeks. In omphalocele, intestines (and sometimes liver) fail to return.
• Herniated viscera covered by sac composed of amnion and peritoneum.
• Umbilical cord inserts into apex of sac.

✅ Model Answer:
• Exomphalos minor (small omphalocele): Defect <5 cm, contains only small bowel → primary fascial closure.
• Exomphalos major (giant omphalocele): Defect >5 cm, contains liver plus other viscera, abdominal cavity small (viscero-abdominal disproportion) → staged closure (silo) or conservative management.
• This infant has exomphalos major (liver-containing, large sac).

✅ Model Answer:
• Cardiac defects (most common, 30-50%): VSD, ASD, TOF, HLHS.
• Chromosomal anomalies (30%): Trisomy 13, 18, 21.
• Beckwith-Wiedemann syndrome (10-15%): visceromegaly, macroglossia, macrosomia, hypoglycemia, ear creases/pits, tumor risk.
• Pentalogy of Cantrell: omphalocele + sternal cleft + diaphragmatic hernia + pericardial defect + cardiac anomaly.
• OEIS complex: Omphalocele, Exstrophy, Imperforate anus, Spinal defects.

✅ Model Answer:
1. Protect sac: Cover with sterile, moist, non-adherent dressing + sterile plastic bag (bowel bag). Do NOT attempt to reduce sac.
2. Place infant in sterile plastic bag (neck down) to maintain warmth.
3. Orogastric (OG) tube – continuous low suction to decompress stomach.
4. IV fluids and broad-spectrum antibiotics (ampicillin + gentamicin + metronidazole).
5. Monitor blood glucose (hypoglycemia – suspect Beckwith-Wiedemann).
6. Investigations: Blood gas, electrolytes, glucose. Echocardiogram, renal ultrasound.
7. Urgent pediatric surgery consultation.

✅ Model Answer:
• Hypoglycemia risk due to Beckwith-Wiedemann syndrome (hyperinsulinism).
• Management: Frequent blood glucose monitoring (every 1-2 hours). IV dextrose infusion (6-8 mg/kg/min) if hypoglycemic. Diazoxide (10-15 mg/kg/day) for hyperinsulinism.
• Untreated hypoglycemia causes brain injury.

✅ Model Answer:
• Primary fascial closure: For small (<5 cm) defects (exomphalos minor) after reduction of viscera.
• Staged closure (silo placement): For exomphalos major (large defect, liver-containing) due to viscero-abdominal disproportion. Spring-loaded or preformed silo placed for gradual reduction over 3-10 days.
• Conservative (non-surgical) management: For giant omphalocele or severe associated anomalies – allow epithelialization, delayed repair.

✅ Model Answer:
• BWS: Overgrowth syndrome due to abnormal imprinting on chromosome 11p15.5 (IGF2 and CDKN1C genes).
• Features: Macroglossia (large tongue), omphalocele/umbilical hernia (50%), macrosomia, neonatal hypoglycemia, ear creases/pits, visceromegaly, hemihyperplasia.
• Tumor risk: Wilms tumor (nephroblastoma), hepatoblastoma, neuroblastoma, adrenocortical carcinoma.
• Surveillance: Abdominal US q3 months until age 7 years; serum AFP q3 months until age 4 years.

✅ Model Answer:
1. Echocardiogram – rule out CHD (30-50%).
2. Renal ultrasound – renal anomalies (agenesis, cystic dysplasia).
3. Spine X-ray/ultrasound – vertebral anomalies.
4. Karyotype/microarray – trisomies 13,18,21.
5. Methylation analysis (11p15.5) – Beckwith-Wiedemann syndrome.
6. Ophthalmology exam – if BWS suspected.

✅ Model Answer:
• Initially NPO – NG/OG tube on suction, IV fluids and parenteral nutrition.
• After surgical closure: Enteral feeds started when bowel function returns (passage of flatus/stool, decreasing NG output) – typically 5-10 days after primary closure, longer after silo.
• Start with small volume continuous feeds, progress to bolus.
• In BWS with macroglossia: Feeding difficulty may require NG or gastrostomy feeds temporarily.

✅ Model Answer:
• Isolated exomphalos minor: Excellent prognosis, normal survival, normal GI function.
• Exomphalos major: Higher morbidity, prolonged ventilation, feeding difficulties. Overall survival >90%.
• Beckwith-Wiedemann syndrome: Normal intelligence (85-90%). Requires tumor surveillance (abdominal US q3 months until age 7, AFP q3 months until age 4). Hypoglycemia usually resolves.

✅ Model Answer:
• “Your baby has exomphalos – a hole in the belly where intestines and liver are covered by a sac.”
• “Large tongue and large size suggest Beckwith-Wiedemann syndrome – an overgrowth syndrome that increases risk of low blood sugar and later kidney or liver tumors.”
• “We will protect the sac, start IV fluids, antibiotics, and monitor blood sugar closely.”
• “Surgery may be done in one operation or gradually using a plastic silo. The outlook is good. Most babies survive.”
• “Long-term follow-up: blood sugar management, tumor screening (abdominal US every 3 months until age 7 years).”
• “This is not your fault. We have a team of specialists to support your family.”