Flexible ureteroscopy for lower calyceal stones in a horseshoe kidney – Is it the new treatment of choice?

Abstract

IntroductionThe efficacy of retrograde intrarenal surgery (RIRS) for the treatment of disorders in a horseshoe kidney has not been sufficiently studied so far. We report on our experience with this method for the treatment of lower-pole calculi in patients with a horse-shoe kidney. Patients and methodsThe files of 9 patients who underwent RIRS for lower calyceal stones in horseshoe kidneys between April 2012 and December 2014 were retrospectively analyzed. The stone-free status, postoperative complications, operative time and duration of hospitalization were assessed. ResultsIn total, 12 renal units with lower calyceal stones were treated, as 3 patients had stones in both kidneys. In 8 renal units complete stone clearance could be achieved in one sitting (67.7%), while in 3 renal units 2 sittings were necessary in order to achieve stone clearance. One patient with a stone sized 18mm still had residual stones after two sittings and, therefore, underwent percutaneous nephrolithotomy (PCNL) for stone clearance. No major complications (Clavien–Dindo grades III–V) were encountered. ConclusionRIRS for the treatment of stone disease in horseshoe kidneys has been shown to be a relatively safe and effective procedure. However, due to the anatomical abnormality, a second look may be needed to render the patient completely stone-free.