Prognostic factors for the safety and efficacy of retrograde laser lithotripsy: Data from a contemporary series of 155 consecutive patients with single and multiple lithiasis of the urinary tract.

Treatment of large and multiple stones located in the ureter and/or the kidney may be challenging. The aim of the current study was to evaluate the results and complications of retrograde endoscopic lithotripsy for stones located in the urinary tract and to determine prognostic factors for treatment outcome. From April 2017 to March 2020, eligible patients for the active treatment of ureterolithiasis with or without concomitant nephrolithiasis <20 mm were enrolled in the study. The prognostic factors for the stone free rate (SFR) after the 1st and subsequent sessions and overall complications were assessed. Patients were divided into single or multiple lithiasis groups (groups A and B respectively). A comparison between these two groups was then conducted. Overall, 237 stones were detected in 155 patients, representing a mean burden of 1.53 stone per patient. The mean total stone size was 14.7 mm, the initial SFR was 80% and the final SFR (after a mean of 1.23 session per patient) was 94.2%. The rate of complications was 26.4%. Multivariative analysis revealed that preoperative stenting and total stone size were independent prognostic factors of initial SFR, while no independent factors were determined for final SFR. Age, total size and stones in the lower calyx were independent factors for complications. In group A and B, 114 and 41 cases with solitary and multiple stones were included, respectively. Excluding operation time (P=0.002), no significant differences were recorded in terms of initial (P=0.255) and final SFR (P=0.056), hospital stay (P=0.308), mean number of treatments (P=0.757) and the rate of complications (P=0.218) between the two groups. In conclusion, retrograde endoscopic management of multiple lithiasis has a favorable outcome irrespective of stone location. Older patients with higher burdens and stones in the lower calyx should be treated with caution.