Which midline defect is covered by amnion and peritoneum, with a mass entering the umbilical cord and AFP normal or elevated?

• A. Omphalocele
• B. Gastroschisis
• C. Wilms tumor
• D. Multicystic dysplastic kidney

Answer: (A)

Omphalocele is a midline abdominal wall defect where abdominal viscera herniate at the base of the umbilical cord and are protected by a sac formed from amnion and peritoneum. This membrane-covered herniation around the umbilicus, with the cord inserting at the edge of the defect, is the hallmark distinguishing feature. AFP levels can be normal or elevated depending on the size of the defect and associated anomalies. By contrast, gastroschisis lies to the side of the umbilicus, with bowel exposed and no covering membrane, and Wilms tumor or multicystic dysplastic kidney are renal conditions, not abdominal wall herniations.