Since 1995 - Non Profit Healthcare Advice

Extra Renal Pelvis



My son is 10 years old. Complains of severe backache. MRI/ ultrasound orthopeadic and neurology exams done. All clear. I was however discovered that he has an extra renal pelvis. What is the best way to move forward? Should it be removed? What are the risks involved? Will it east the pain? Can surgery be avoided? Thank you!


Urine produced by the kidney drains into the renal pelvis, which collects the urine until it flows down through the ureters into the urinary bladder. In most individuals the renal pelvis is small. Occasionally it is enlarged and protrudes out from the kidney, called an extrarenal pelvis; the term extrarenal simply means that it is protruding out, but the implication is that this is a normal anatomic variant.

If the back pain is only on that side, in the flank area, is intermittent and severe, then the finding of an extrarenal pelvis could be a sign of intermittent obstruction to the upper urinary tract where the renal pelvis joins the ureter. One way to determine whether this is the case would be to do a renal sonogram at the time of the flank or back pain. In that case, it should show more severe hydronephrosis (swelling of the renal pelvis and calyces of the kidney).

For more information:

Go to the Urinary Disorders health topic.