Ischiospinal dysostosis (ISD) is a recently described entity characterized by ischial hypoplasia and spinal segmental anomalies. Nephroblastomatosis that may manifest radiologically as 'polycystic kidney disease' has been regarded as a syndromic constituent of ISD. We report two children with ISD associated with 'renal cystic disease'. One child had multiple renal cysts resembling radiologically adult polycystic kidney disease, leading to renal dysfunction, whereas the other a solitary renal cyst with normal renal function. Renal malformations in ISD may be variable, ranging from diffuse nephroblastomatosis to a solitary renal cyst.