Multicystic renal dysplasia; a perinatal autopsy examination of a neonate

Multicystic renal dysplasia is a rare developmental anomaly of the kidney, often associated with urinary tract obstruction and incompatible with long-term survival when bilateral. Early recognition through antenatal imaging and confirmation by post-mortem examination are crucial for accurate diagnosis and genetic counselling. We present a case of a 31-year-old P2C0 mother who delivered a baby at 36 weeks of gestation. The antenatal ultrasound scan performed at 16 weeks revealed oligohydramnios, and a subsequent foetal anomaly scan showed multicystic kidneys with absent liquor. Further imaging suggested lower urinary tract obstruction, leading to progressive renal impairment and pulmonary hypoplasia. The baby died a few hours after birth. Post-mortem examination revealed a non-syndromic baby with bilateral cystic kidneys, left ureteric atresia, lung hypoplasia, and a large ostium secundum atrial septal defect. Microscopically, both kidneys showed variably sized cysts lined by cuboidal epithelial cells, surrounded by immature mesenchymal stroma with primitive tubules, glomerular structures, and focal cartilage islands. The diagnosis of bilateral multicystic renal dysplasia with left ureteric atresia was made. This case highlights the diagnostic value of foetal autopsy in elucidating the underlying pathology of congenital renal anomalies and its pivotal role in reproductive counselling for future pregnancies.