Early medullary cystic disease: a urographic diagnosis?

Excretory urography of a patient with an early stage of medullary cystic disease demonstrated an inhomogeneous, streaky nephrogram confined to the medulla, presumably due to accumulation of contrast material in dilated tubules. This was seen best one to two hours after contrast injection and may represent a specific urographic finding which does not appear to have been described previously in this condition.