Efficacy and safety of fURS in stones larger than 20 mm: is it still the threshold?

Comparison of Shock Wave Lithotripsy and Flexible Ureterorenoscopy in the Treatment of 10-20 mm Lower Pole Stone: Prospective Non-randomized Study

INTRODUCTION

The objective of the study is to clarify the efficiency, safety, and limitations of shock wave lithotripsy (SWL) and flexible ureterorenoscopy (f-URS) in the management of lower pole stones (LPS).

METHODS

The present study was planned prospectively in a non-randomized manner. Patients who had LPS between 10 and 20 cm in size were enrolled in the study. Patient demographic characteristics, stone-related parameters, complications, and success were noted. Patients who underwent SWL and patients who underwent f-URS were compared according to demographic characteristics, procedure-related parameters, complications, and success rate.

RESULTS

A total of 82 patients matched the study inclusion criteria, with 44 patients treated with SWL and 38 patients treated with f-URS. The time between diagnosis and the end of the treatment was 29.2 days in the SWL group and 15.2 days in the f-URS group (p = 0.001). The success rate was 89.5% with f-URS and 72.7% with SWL (p = 0.036). Receiver operating curve analysis revealed that a stone size larger than 14 mm in the lower pole was significantly associated with SWL failure (area under the curve [AUC]: 0.711, p = 0.033), and a stone size larger than 16 mm was a predictive factor for f-URS failure.

CONCLUSION

The present study found that f-URS had a significantly higher stone-free rate in the management of 10-20 mm LPS compared to SWL. For the first time, this study showed that the time between diagnosis and the end of treatment was significantly shorter with f-URS. Moreover, LPS larger than 14 mm and 16 mm were predictive factors for SWL and f-URS failure, respectively.

Risk factors for infectious complications after retrograde intrarenal surgery - a systematic review and narrative synthesis

Introduction

Infectious complications are among the most frequent and significant complications in retrograde intrarenal lithotripsy. To date, review articles have covered complications after a ureteroscopy, but not after retrograde intrarenal surgery (RIRS), specifically. Because the complications and risk factors are different for a ureteroscopy and RIRS, we aimed to identify variables related to the occurrence of infectious complications post-RIRS.

Material and methods

This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. We included original studies that described 100 or more procedures published in 2014–2021. We extracted data and performed a narrative synthesis to explore and interpret differences between the studies.

Results

We selected 17 studies for analysis, including 10 from 2019–2021. Infectious complications after RIRS were observed in 2.8–7.5% of patients (mean 7.1%). We found seven independent risk factors associated with infectious complications after RIRS: long operative time, recent history of positive urine culture or urinary tract infection or antibiotic use, pyuria/nitrites, small caliber of ureteral access sheath, struvite stone, high irrigation rate, and comorbidities.

Conclusions

If an increased rate of infectious complications is found at a RIRS center, countermeasures should include restrictions on operative time and irrigation rate, and consideration of larger access sheaths, especially for patients with abnormal urine results or with struvite stones or with a history of urinary tract infection or co-morbidities.