DDX of abnormalities of renal ascent

Approach to the DDX of abnormalities of renal ascent: 

  • When a kidney is either absent from its renal fossa or appears abnormally rotated in its renal fossa, the patient should be investigated for abnormalities of renal ascent
  • Ultrasound is the modality of choice to look for an ectopic kidney in the pelvis and along the path of renal ascent
  • If a kidney cannot be found by ultrasound and a definitive diagnosis of renal agenesis is required, DMSA renal scintigraphy or MRI of the abdomen may be use