Which lethal autosomal recessive syndrome presents with oligohydramnios, infantile polycystic kidney disease, bladder not visualized, and encephalocele?

• A. Meckel-Gruber syndrome
• B. Triploidy
• C. Down syndrome
• D. Turner syndrome

Answer: (A)

This pattern is classic for a lethal fetal syndrome that is autosomal recessive and presents with a triad of anomalies: occipital encephalocele, bilateral cystic or polycystic kidneys with resulting oligohydramnios, and often nonvisualization of the bladder due to impaired renal function. Those features together point to Meckel-Gruber syndrome. It is known for the combination of central nervous system malformations (encephalocele), severe renal dysplasia with oligohydramnios, and hepatic or other organ anomalies, leading to a perinatal lethality.

Other conditions listed do not routinely show this same constellation. Triploidy can involve multiple anomalies and hydropic changes, but the specific triad of occipital encephalocele with infantile polycystic kidneys and absent bladder is most characteristic of Meckel-Gruber. Down syndrome and Turner syndrome have distinct ultrasound and clinical patterns that do not align with this combination.