Multicystic dysplastic kidney and pelviureteric junction obstruction.

Two infants with nonfunctioning antenatally detected multicystic dysplastic kidneys developed acute renal failure in conjunction with pelviureteric obstruction of the contralateral kidney at 9 and 14 months of age, respectively. The initial postnatal ultrasounds had shown mild pelvic dilatation in both cases. Clinicians need to be aware of the possibility of late obstruction. We suggest that it is good practice to review patients with antenatally detected urinary tract abnormalities and equivocal investigations at joint nephrouroradiology meetings.