Case Study - December 2009

This is a 69-year-old woman with a history of left renal calculi who presented with recurrent left flank pain and a Proteus urinary infection.
- What does the CT scan show?
- What further investigations need to be performed?
- How should the condition be managed?
Reveal Answer
Open answer There is no fixed answer to this question, however your response should be similar to the one below:
- The CT shows an 8mm calculus in the lower pole of the left kidney but, in addition, shows a dilated left renal pelvis with a normal ureter below, suggestive of pelviureteric junction (PUJ) obstruction
- The best means of confirming the obstruction would be a diuresis renogram (MAG3); a retrograde ureterogram would also ensure that the ureter itself is normal
- Treatment would be by pyeloplasty (open or laparoscopic), endopyelotomy (retrograde or antegrade) or balloon dilatation of the ostructing segment at the PUJ. To prevent further stone growth (due to Proteus), she should commence long-term, low-dose antibiotic treatment until definitive surgery has been performed.
The patient was referred for further shockwave lithotripsy, which she had undergone before, without any appreciation that there was an underlying obstruction which would preclude stone elimination.