Abstract
Polycystic kidney disease includes many different disease entities; however, inborn error of organic acid metabolism is not usually a prime suspect. We report our experience with polycystic kidneys and thickened myocardium in newborn siblings with the further diagnosis of glutaric aciduria type II in the younger sister. Both female fetuses were found to have enlarged hyperechoic kidneys and thickened myocardium on fetal ultrasound in two singleton pregnancies. Both were delivered at term by cesarean section due to reduced amniotic fluid and developed metabolic acidosis on the same day. In the older sister, autosomal recessive polycystic kidney disease was suspected based on negative family history, clinical course, and renal histological findings. However, the younger sister was confirmed to have glutaric aciduria type II through urine and fibroblasts analyses. Therefore, the older sister was also suspected to have the same disease. Although polycystic kidneys and cardiac steatosis are associated with glutaric aciduria type II, cardiac lesion has not been described as a requisite extrarenal lesion for the differential diagnosis of polycystic kidney disease. The combination of enlarged hyperechoic kidneys and thickened myocardium on fetal ultrasound suggests glutaric aciduria type II, and organic acid analysis should be conducted on amniotic fluid or postnatal urine to make the diagnosis.
