Ureteroscopic treatment of patients with small, painful, non-obstructing renal stones: the small stone syndrome

Abstract

Although it is thought that renal colic results from urinary tract obstruction, some patients evaluated for renal colic are found to have no source for their pain other than small, non-obstructing renal calyceal stones. We refer to this as "the small stone syndrome". We aim to determine if small non-obstructing calyceal stones may also cause pain and that treatment may relieve this pain. A retrospective chart review was performed to identify patients with non-obstructing calyceal stones (≤ 4 mm in diameter) evaluated for flank pain and treated by ureteroscopy. Patients completed a follow-up questionnaire regarding pre- and postoperative pain and quality of life (QOL). 13 patients were included in the analysis. Mean stone diameter was 3 mm (range 1.5 - 4.0 mm). Following ureteroscopy, 11 (85%) patients reported complete resolution of pain and 2 (15%) reported partial resolution. 12 patients were able to describe preoperative and postoperative QOL and of these, 8 (67%) had improved QOL, 4 (33%) had no change, and none reported worsening. Follow-up imaging was available in 10 patients: stone free in 6 (60%), reduction in stone size in 3 (30%), and stone unchanged in 1 (10%). Ureteroscopic treatment of painful small, non-obstructing renal calyceal stones achieved complete or partial resolution of pain in all patients and improvement in QOL in a majority of patients.