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The effect of ideal urine culture time on urinary infections after flexible ureteroscopy: A match-pair case-control
Mehmet Çağlar Çakıcı1, Özgür Kazan1, Muhammet Çiçek1
1Department of Urology, Istanbul Medeniyet University Goztepe Training and Research Hospital, Istanbul, Turkey.
Aims:
To investigate the effect of the ideal period (Δ-day), which is a period between the sterile urine culture and initiation of flexible ureteroscopy (f-URS), on postoperative urinary tract infections (UTI) in our tertiary referral centre.
Methods:
After obtaining the approval of the local ethics committee, retrospective data were collected for all f-URS procedures performed between January 2017 and March 2019. Patients that developed UTI were matched in 1:1 proportion with patients that did not develop UTI based on their demographic and stone characteristics. The group of patients with postoperative UTI was compared with the control group.
Results:
A total of 916 f-URS cases that had all required data were analysed. Sixty-eight patients with postoperative UTI were determined and a total of 136 patients were included in the study after match-pair. We found that if the Δ-day is longer than 2 weeks, the possibility of postoperative urinary infection rates increases with statistical significance (P = .006). According to our subgroup analysis, postoperative UTI was more common if the Δ-day >14 days. ROC curve analysis provided a 14.5-day period as a cut-off value of Δ-day for postoperative UTI.
Conclusions:
The present study is the first to examine the impact of the Δ-day for f-URS on postoperative UTIs. In brief, prolonging the Δ-day, especially if Δ-day >14 days, leads to an increase in the rates of postoperative UTI. We conclude that it is preferred to either perform the f-URS in the early period after the urine culture analysis or doing the urine culture analysis shortly before the surgery.
Insights
Delaying flexible ureteroscopy (f-URS) after sterile urine culture increases postoperative urinary tract infection (UTI) risk. Performing f-URS within 14 days of urine culture is recommended to minimize infection rates.
Area of Science:
- Urology
- Infectious Diseases
- Surgical Outcomes
Background:
- Postoperative urinary tract infections (UTIs) are a common complication following flexible ureteroscopy (f-URS).
- The optimal timing between sterile urine culture and f-URS initiation to minimize UTI risk is not well-established.
Purpose of the Study:
- To investigate the impact of the interval (Δ-day) between sterile urine culture and f-URS on postoperative UTI rates.
- To identify an ideal time window to reduce infection risk in patients undergoing f-URS.
Main Methods:
- Retrospective analysis of 916 f-URS cases performed between January 2017 and March 2019.
- 1:1 matched-pair analysis comparing patients with and without postoperative UTI based on demographics and stone characteristics.
- Receiver Operating Characteristic (ROC) curve analysis to determine the optimal Δ-day cut-off.
Main Results:
- A total of 136 patients (68 with UTI, 68 controls) were included after matching.
- A statistically significant increase in postoperative UTI rates was observed when the Δ-day exceeded 2 weeks (P = .006).
- ROC analysis identified a Δ-day of 14.5 days as the cut-off value for increased UTI risk.
Conclusions:
- Prolonging the interval (Δ-day) between sterile urine culture and f-URS, particularly beyond 14 days, significantly increases the risk of postoperative UTIs.
- It is recommended to perform f-URS promptly after urine culture or to conduct urine culture shortly before the procedure to mitigate infection risk.
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