Introduction:
The global prevalence of urolithiasis tends to increase worldwide,
leading to the need for safe and effective treatment
methods1. In parallel with the advances in technology,
flexible ureterorenoscopes, effective lithotripters and innovations in
auxiliary equipment have enabled the treatment most of the renal stones
with flexible ureterorenoscope with no need for open surgery or
percutaneous nephrolithotomy)2. Although the
percutaneous nephrolithotomy (PNL) is recommended as first-line
treatment for renal stones larger than 20 mm in size, flexible
ureterorenoscopy (FURS) or shock wave lithotripsy (SWL) may be
considered as a treatment method for stones larger than 20 mm in size
according to EAU-2019 guideline on urolithiasis especially in case that
PNL is not an option because of other reasons3.
Due to the increasing spread of FURS, it should be addressed in all
aspects, including infection rates. Postoperative infections seem one of
the most common complications of FURS and the parameters that affect
infective complications following FURS were analysed in some studies in
the literature4,5. However, the effect of operation
time (OT) and the relationship of the ureteral access sheath (UAS) with
the infection rates is unclear in this size of renal stones.
We aimed to investigate the relationship of the OT and the UAS usage
with the infection rates and to determine a cut-off value in terms of
OT, where infection rates increase more, by using ROC curve analysis.