Bridging the knowledge gap: past, present and future of antibiotic use for ureteral stents

OBJECTIVE

To evaluate the available literature on ureteric stent-related infections, the use of antibiotics and bacterial colonisation to identify the current incidence of stent-related infections, unveil knowledge gaps and generate potential hypotheses for future research.

METHODS

A literature review was conducted using PubMed, Cochrane and urological association websites identifying relevant English literature published between 1983 and January 2024.

RESULTS

There is a worldwide lack of guidelines for antibiotic prophylaxis for stent placement, exchange or extraction. In patients with a negative preoperative urine culture undergoing ureteroscopy and stent placement, it may be considered to only provide prophylaxis in presence of risk factors. However, in pre-stented patients a preoperative urine culture is important to guide prophylaxis during endourological surgery. During stent indwell time, antibiotic prophylaxis does not show any advantage in preventing urinary tract infections (UTIs). There is no strong evidence to support the use of antibiotics at time of stent removal. In the absence of any clear evidence, management strategies for treating UTIs in patients with ureteric stents vary widely. Stent exchange could be considered to remove the biofilm as a potential source of bacteria. Stent culture can help to guide treatment during infection as urine culture and stent culture can differ.

CONCLUSION

In terms of good antibiotic stewardship, urologists should be aware that unnecessary use of antibiotics provokes bacterial resistance. There is a great need for further research in the field of antibiotic prophylaxis and stent-related infections to develop evidence that can help shape clear guidelines for this very common urological practice.

Recent advances in the treatment of renal stones using flexible ureteroscopys

Upper urinary tract stones are a common urological disease that can be treated by flexible ureteroscopy (FURS) through the natural urinary tract, in addition to extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy. The advantages of FURS are less trauma, faster recovery, and fewer complications, while its disadvantages include poor results of lithotripsy and stone extraction when dealing with larger stones, and prolonged operation time. Over the last two decades, the emergence of new technologies such as FURS combined with negative pressure suction, robot-assisted FURS, and artificially intelligent FURS, coupled with improvements in laser technology (the use of thulium fiber lasers and the invention of single-use flexible ureteroscopes (su-fURS) suitable for primary level application, have significantly increased the global adoption of FURS. This surge in usage holds a promising future in clinical application, benefiting a growing number of patients with renal calculi. Accompanied by changes in technical concepts and therapeutic modalities, the scope of indications for FURS is broadening, positioning it as a potential primary choice for urolithiasis treatment in the future. This review outlines the progress in employing FURS for the treatment of renal calculi in order to generate insights for further research.

Urinary tract infection after flexible ureterorenoscopy for urolithiasis in patients with positive treated preoperative urinalysis

Prevalence of kidney stones is increasing worldwide, flexible ureterorenoscopy (f-URS) is the most common surgical treatment. Postoperative urinary tract infection (PUTI) is the primary complication. Some risk factors are classically associated with PUTI, especially preoperative positive urinalysis (POPU). We aimed to identify risk factors for PUTI after f-URS for urolithiasis in patients with treated POPU, and to identify the different pre and postoperative pathogens. Retrospective, single-center study of all f-URS for urolithiasis between January 2004 and December 2020. Procedures with treated POPU were categorized as PUTI or no PUTI (NPUTI). We examined demographics, preoperative, perioperative and postoperative characteristics in each group. Among 1934 procedures analyzed, 401 (20.7%) had POPU; these were categorized into NPUTI (n = 352, 87.8%) and PUTI (n = 49, 12.2%). By univariate analysis, only preoperative stenting duration (76.3 in NPUTI group vs 107.7 days in PUTI group, p = 0.001) was significantly associated with a higher risk of PUTI in univariate analysis. Germ distribution was similar in both groups. We compared pre- and postoperative microbiological data for interventions with PUTI, and found that only 8.7% of pathogens were identical between pre and postoperative urinalysis. Our study shows that the rate of PUTI is higher for patients with a POPU and that preoperative stent duration is the sole risk factor in patients with POPU. The low concordance rate (8.7%) between POPU and post-operative pathogens highlights the need for further research on obtaining sterile preoperative urinalysis, or performing intraoperative culture (urines, stent or stone), to treat PUTI early with an adapted antibiotic therapy.

A comparative study of flexible ureteroscopic lithotripsy for upper urinary tract stones in patients with prior urosepsis following emergency drainage via retrograde ureteral stent or percutaneous nephrostomy

BACKGROUND

Patients with urosepsis associated with upper urinary tract stones require further stone management after emergency drainage.

OBJECTIVE

To evaluate the safety and efficacy of elective flexible ureteroscopic lithotripsy (F-URSL) for upper urinary tract stones in patients with prior urosepsis who have undergone emergency drainage using retrograde ureteral stent(RUS) or percutaneous nephrostomy (PCN).

METHOD

Between January 2017 and December 2021, clinical data were collected for 102 patients who underwent elective F-URSL following emergency drainage for urosepsis caused by upper ureteral or renal stones. The patients were categorized into two groups based on the drainage method used: the RUS group and the PCN group. The collected data included patient demographics, stone parameters, infection recovery after emergency drainage, and clinical outcomes post F-URSL. Subsequently, the data underwent statistical analysis.

RESULTS

A total of 102 patients were included in the statistical analysis, with 58 (56.86%) in the RUS group and 44 (43.14%) in the PCN group. Among the patients, 84 (82.35%) were female and 18 (17.65%) were male, with an average age of 59.36 years. Positive urine cultures were observed in 71 (69.61%) patients. Successful drainage was achieved in all patients in both groups, and there were no significant differences in the time required for normalization of white blood cell count (WBC) and body temperature following drainage. Additionally, all patients underwent F-URSL successfully, and no statistically significant differences were observed between the two groups in terms of operative time, stone-free rates, postoperative fever, and postoperative hospital stay.

CONCLUSION

Both RUS and PCN have been established as effective approaches for managing urosepsis caused by upper urinary tract stones. Furthermore, the impact of these two drainage methods on the subsequent management of stones through elective F-URSL has shown consistent outcomes.

Does gender influence retrograde intrarenal surgery (RIRS) outcomes? Data from the Flexible Ureteroscopy Outcomes Registry (FLEXOR)

INTRODUCTION AND OBJECTIVES

As well established flexible ureteroscopy (RIRS). There is still no evidence if gender can have any influence on the outcomes and complication when performing. This study aims to evaluate the role that gender has in performing flexible ureteroscopy from a large series of patients.

METHODS

This study retrospectively analyzed patients who underwent RIRS for renal stones from January 2018 to August 2021 within the multicentric FLEXOR registry. Demographics, stone characteristics, perioperative findings, results and complications were analyzed and compared between gender groups.

RESULTS

A total of 6669 patients were included, 66.1% were male and 33.9% were female. Stone characteristics was comparable between groups. Female patients had significant higher fever and positive urine culture rates (12% vs. 8% and 37% vs. 34%). Also, females had a slight longer hospital stay (3.8 vs. 3.5 days; P < 0.001) and more residual fragments after the procedure (23.03% vs. 20.97 (P = 0.032). Overall complications were slightly significantly higher in women (15.74% vs. 14% (P = 0.042)) mainly at the expense of fever rates (6.9% vs. 5.7%) whereas the risk of sepsis was similar in both groups. A multivariate analysis showed that larger stone size, multiple and lower pole stones seem to have a negative impact in the incidence of residual stones and complications.

CONCLUSION

Our real life global study reflects that female gender may have a correlation with a slightly increased residual fragment rate and overall low grade complications. However, women can safely be treated with RIRS with no increased the rate of sepsis with appropriate care.

Influencing factors of acute kidney injury following retrograde intrarenal surgery

PURPOSE

To investigate the influencing factors of acute kidney injury (AKI) following retrograde intrarenal surgery (RIRS).

METHODS

The data of patients who underwent RIRS for kidney stones between January 2018 and June 2022 at two tertiary centers were retrospectively analyzed. Demographic data of patients were obtained. According to kidney disease: Improving Global Outcomes (KDIGO) criteria, those with and without AKI were divided into two groups. Preoperative, intraoperative, and postoperative predictive factors of patients were investigated between the groups. In addition, the influencing factors of AKI were examined by multivariate analysis.

RESULTS

This study included 295 (35.7%) women and 532 (64.3%) men. The mean age was 50.03 ± 15.4 years (range 18-89), and mean stone size was 15.5 ± 6.1 mm (range 6-47). Overall, 672 of patients (81.3%) were stone-free after the initial treatment. According to KDIGO, 110 of patients (13.3%) had AKI during the postoperative period. Univariate analysis showed that stone size (P = .003), previous stone surgery (P = .010), renal malformations (P = .017), high operative time (P =  < .001), high preoperative creatinine value (P = .036), intraoperative complications (P = .018), and postoperative urinary tract infection (P = .003) had significant influence on the AKI after RIRS. Multivariate analysis excluded previous stone surgery, high preoperative creatinine value, renal malformations, and intraoperative complications from the logistic regression model, whereas other factors maintained their statistically significant effect on AKI, indicating that they were independent predictors.

CONCLUSIONS

Stone size, operative time, postoperative urinary tract infection, and diabetes mellitus are significant predictors of AKI. During RIRS, urologists should consider the factors that increase the risk of AKI and evaluate the treatment outcomes based on these factors.

RIRS with disposable or reusable scopes: does it make a difference? Results from the multicenter FLEXOR study

Introduction

With several single-use ureteroscopes now available, our aim was to analyze and compare data obtained globally from high-volume centers using both disposable and reusable flexible ureteroscopes and see if indeed in real-world practice either scope has a distinct advantage.

Methods

Retrospective analysis was performed on the FLEXOR registry, which was created as a TOWER group (Team of Worldwide Endourological Researchers, research wing of the Endourological Society) endeavor. Patients who underwent retrograde intrarenal surgery (RIRS) for renal stones from January 2018 to August 2021 were enrolled from 20 centers globally. A total of 6663 patients whose data were available for analysis were divided into Group 1 (Reusable scopes, 4808 patients) versus Group 2 (Disposable scopes, 1855 patients).

Results

The age and gender distribution were similar in both groups. The mean stone size was 11.8 mm and 9.6 mm in Groups 2 and 1, respectively (p < 0.001). Group 2 had more patients with >2 cm stones, lower pole stones and of higher Hounsfield unit. Thulium fiber laser (TFL) was used more in Group 2 (p < 0.001). Patients in Group 2 had a slightly higher stone-free rate (SFR) (78.22%) and a lower number of residual fragments (RFs) compared with Group 1 (p < 0.001). The need for further treatments for RF and overall complications was comparable between groups. On multivariate analysis, overall complications were more likely to occur in elderly patients, larger stone size, lower pole stones, and were also more when using disposable scopes with longer operative time. RFs were significantly higher (p < 0.001) for lower pole, larger, harder, multiple stones and in elderly.

Conclusion

Our real-world practice observations suggest that urologists choose disposable scopes for bigger, lower pole, and harder stones, and it does indeed help in improving the single-stage SFR if used correctly, with the appropriate lasers and lasing techniques in expert hands.

Infection after ureteroscopy for ureteric stones: analysis of 71 305 cases in the Hospital Episode Statistics database

OBJECTIVES

To investigate the burden of infectious complications following ureteroscopy (URS) for ureteric stones on a national level in England using data from the Hospital Episodes Statistics (HES) data warehouse.

MATERIALS AND METHODS

A retrospective cohort was identified and followed up in HES during the period April 2013 to March 2020 for all procedure codes relating to ureteroscopic stone treatment (M27.1, M27.2, M27.3). Treatment episodes relating to the first URS ('index ureteroscopy') for each patient were further analysed. All subsequent admissions within 30 days were also captured. The primary outcome was diagnosis of urinary tract infection (UTI; including all codes relating to a UTI/sepsis within the first 30 days of index URS). Secondary outcomes were critical care attendance, attendance at the accident and emergency department (A&E) within 30 days, and mortality.

RESULTS

A total of 71 305 index ureteroscopies were eligible for analysis. The median age was 55 years, and 81% of procedures were elective and 45% were undertaken as day-cases. At the time of index URS, 16% of patients had diabetes, 0.5% had coexisting neurological disease and 40% had an existing stent/nephrostomy. Overall, 6.8% of the cohort (n = 4822) had a diagnosis of UTI within 30 days of index URS (3.9% immediately after surgery). A total of 339 patients (0.5%) required an unplanned stay in critical care during their index URS admission; 8833 patients (12%) attended A&E within 30 days. Overall mortality was 0.18% (60 in-hospital, 65 within 30 days); 40 deaths (0.056%) included infection as a contributing cause of death.

CONCLUSION

We present the largest series evaluating infectious complications after ureteroscopic stone treatment. The procedure is safe, with low inpatient infective complication and critical care admission rates.

QSOFA and SOFA scores are valuable tools for predicting postoperative sepsis resulting from ureteroscopic lithotripsy (URSL)

The sequential organ failure assessment (SOFA) and quick sequential organ failure assessment (qSOFA) scores are new tools which are used to assess sepsis based on the Third International Consensus Definitions for Sepsis and Septic Shock Task Force. This study aimed to evaluate the feasibility of using the SOFA and qSOFA to predict post-ureteroscopic lithotripsy (URSL) sepsis. Patients who underwent URSL due to ureteral stone obstruction were retrospectively reviewed using SOFA and qSOFA scores. Patient characteristics including age, gender, comorbidities, American Society of Anesthesiologists Classification, stone burden, stone location, hydronephrosis status, infectious status, preoperative SOFA and qSOFA score were collected. Preoperative factors were analyzed to determine if they were correlated with postoperative sepsis. A total of 830 patients were included in this study, of whom 32 (3.9%) had postoperative sepsis. Multivariate analysis revealed that older age, proximal ureteral stones, severe hydronephrosis, and high preoperative qSOFA or SOFA score were significantly associated with postoperative sepsis. The areas under the curves of a qSOFA score ≥ 1 and SOFA score ≥ 2 for predicting postoperative sepsis were 0.754 and 0.823, respectively. Preoperative qSOFA and SOFA scores are convenient and effective for predicting post-URSL sepsis. Further preventive strategies should be performed in these high-risk patients.

Risk of Sepsis in Retrograde Intrarenal Surgery: A Systematic Review of the Literature

Context

Objective

Evidence acquisition

Evidence synthesis

Conclusions

Patient summary

Does time elapsed between urine culture and retrograde intrarenal surgery affect the rate of systemic inflammatory response syndrome?

OBJECTIVE

To identify the preoperative and intraoperative factors that might cause systemic inflammatory response syndrome (SIRS) after retrograde intrarenal surgery (RIRS), and to investigate the effect of time elapsed between the date of performing preoperative bladder urine culture (PBUC) and surgery date on postoperative SIRS.

MATERIALS AND METHODS

Four hundred sixty-seven patients who had RIRS between January 2013 and June 2020 constituted the target population of this study. PBUC were obtained from all patients before undergoing surgery. Postoperatively, patients were closely monitored for fever and other signs of SIRS. Univariate and multivariate logistic regression analysis were performed to reveal the predictive factors for SIRS after RIRS.

RESULTS

The entire study cohort consisted of 467 patients. The rate of SIRS was 5.6%. In univariate analysis, the rate of DM, recurrent urinary tract infection (UTI) history, surgical time, and stone burden were significant predictive factors for SIRS. In multivariate analysis, the rate of recurrent UTI history, surgical time and stone burden were observed to be statistically significant predictive factors. Time elapsed between the date of performing PBUC and surgery date was not different between the SIRS group and the normal group.

CONCLUSION

We conclude that the time between the date of performing PBUC and surgery date is not an influential factor for SIRS. Clarifying this issue with prospective studies may be useful, as endourologists frequently encounter this situation in daily practice.

Retrospective Analysis of the Risk Factors and Drug Resistance of Pathogenic Bacteria in Systemic Inflammatory Response Syndrome After Ureteroscopic Holmium Laser Lithotripsy for Impacted Ureteral Calculi

Objective

To investigate the risk factors, pathogen distribution, and drug resistance of systemic inflammatory response syndrome (SIRS) after holmium laser ureteroscopic lithotripsy for impacted ureteral calculi (HLULIUC).

Patients and Methods

The clinical data of 293 patients with HLULIUC in our hospital from October 2017 to February 2021 were retrospectively collected, including age, BMI, stone size, operation time, urine routine, urine culture, basic illness, complete blood count, liver and kidney function, etc. Patients were divided into SIRS and non-SIRS groups according to whether they had SIRS or not. Then the differences in clinical data, blood and urine bacterial culture results, and drug resistance between the two groups were analyzed.

Results

The incidence of SIRS after HLULIUC was 17.75%. Logistic regression analysis showed that the risk factors of SIRS after HLULIUC include ureteral calculi≥1cm (OR=2.839, 95% CI=1.341–5.647, P=0.021), long operation time (OR=4.534, 95% CI=2.597–12.751, P=0.017), diabetes mellitus (OR=3.137, 95% CI=1.142–7.319, P=0.012), increased preoperative C-reactive protein (OR=1.864, 95% CI=1.05–4.347, P=0.032), and positive urine leukocytes (OR=3.514, 95% CI=1.7237–9.734, P=0.007) and culture (OR=6.034, 95% CI=3.097–15.751, P<0.001) before operation. The main pathogens causing SIRS after HLULIUC were Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, and Pseudomonas aeruginosa. The pathogenic bacteria are sensitive to drugs including piperacillin/tazobactam, meropenem, tigecycline, teicoplanin, vancomycin, and imipenem. The resistance rates to quinolones (such as levofloxacin) and to the second- and third-generations of cephalosporins were as high as 52.94%–90.19%.

Conclusion

Ureteral calculi≥1cm, long operation time, diabetes, increased C-reactive protein, and preoperative positive urine leukocytes and culture are independent risk factors of SIRS after HLULIUC. Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, and Pseudomonas aeruginosa are the main pathogenic bacteria for SIRS after HLULIUC. The pathogenic bacteria are sensitive to drugs, including piperacillin/tazobactam, meropenem, tigecycline, teicoplanin, vancomycin, and imipenem.

Impact of eliminating urethral catheterization following ureterorenoscopic lithotripsy

OBJECTIVES

To show that elimination of a urethral catheter in ureterorenoscopic lithotripsy cases is not disadvantageous.

METHODS

We reviewed 164 non-catheterized patients (experimental group) and 656 catheterized patients (control group) with renal or ureteral stones treated at our institution. Inclusion criteria were initial operation, patient age 18 to 75 years, no dysuria, and no preoperative febrile urinary tract infection due to calculi. The primary areas of evaluation were patient background, stone characteristics, perioperative factors, and postoperative evaluation results.

RESULTS

The proportion of women was significantly lower (24.4% vs 37.2%; P = 0.01) and the proportion of multiple stone cases was significantly higher (34.9% vs 19.2%; P < 0.001) in the experimental as compared to the control group, while there were no significant differences for patient background or stone characteristics. The percentages of short-term preoperative stent insertion (72.0% vs 33.0%; P = 0.009) and negative preoperative urine culture cases (58.0% vs 23.0%; P < 0.001) were significantly higher in the experimental than in the control group, with no differences regarding other perioperative factors. There was no significant difference for complete stone clearance rate between the groups (P = 0.339), while only one patient underwent re-catheterization and there were no cases of urinary retention. Interestingly, the rate of postoperative febrile urinary tract infection was significantly lower (P = 0.024) in the experimental (5.7%) than in the control (9.0%) group.

CONCLUSION

Postoperative urethral catheterization can be eliminated in low-risk ureterorenoscopic lithotripsy cases, although additional studies are needed.

Post-Ureteroscopy Infections Are Linked to Pre-Operative Stent Dwell Time over Two Months: Outcomes of Three European Endourology Centres

Background: The aim of this study is to investigate outcomes of pre-operative stent dwell time on infectious complications following ureteroscopy and stone treatment to identify a time cut-off. Material and Methods: Three tertiary referral centres in Europe retrospectively collected outcomes of ureteroscopy and laser fragmentation (URSL) for all patients with pre-operative indwelling ureteric stents over a period of up to 5 years. Data was collected on patient details, stone demographics, stent dwell time, complications and stone free rate (SFR). Matching for age, sex, operative time, stone size and post-operative stent insertion. To examine for a threshold effect, monthly cut-offs were used to compare post-ureteroscopic febrile UTIs. Binomial logistic regression was used (SPSS v.24) with a significance level set at 0.0036. The risk ratio (RR) with a 95% confidence interval (CI) and the number needed to harm (NNH) are reported. Results: There were 467 patients with a pre-operative stent for analysis. These patients (n = 315) were matched to non-stented controls after excluding 152 patients to achieve adequate matching. There was a significant difference in rates of post-ureteroscopic febrile UTI between stented vs non-stented patients (RR = 2.67, 95% CI: 1.10–6.48, p = 0.03). On adjustment, a dwell time of more than two months was associated with an increased risk of post-ureteroscopic febrile UTI (RR = 3.94, 95% CI: 1.30–12.01, p = 0.02), this increased risk rose with longer dwell time. At stent time longer than four months was associated with a significantly increased risk of post-ureteroscopic febrile UTI (5% vs. 15%, RR = 3.09, 95% CI: 1.56–6.10, p = 0.001), with the number needed to harm at 10. Conclusions: Overall infectious complication rates from URSL are low. The risk of post-operative UTI after four months of dwell time is nearly tripled compared to less than four months.

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.

Flexible Ureterorenoscopy under Spinal Anesthesia: Focus on Technique, Results, Complications, and Patients' Satisfaction from a Large Series

INTRODUCTION

Although spinal anesthesia (SA) may reduce postoperative morbidity, most urologists perform flexible ureterorenoscopy (fURS) under general anesthesia (GA). The objective of our study is to provide technical details, results, complications, and patients' satisfaction with fURS performed under exclusive SA.

METHODS

We analyzed all consecutive fURS performed under SA to treat renal stones from March 2011 to February 2017. Details of technique, operative time, outcomes, need for further treatments, complications, and patients' satisfaction were evaluated.

RESULTS

Two hundred thirty-four fURS under SA were considered. SA was performed through L2-L3 vertebral interspace in 64.1%. Patients were discharged the same day of surgery. Mean stone burden was 13.5 ± 6.6 mm and mean operative time 76.9 ± 34.6 min. Single-procedure SFR was 69.7%. Further treatments were performed in 22.8%. 96.6% had no anesthesia-related complications. No Clavien-Dindo grade ≥ IIIb complications were noticed. 99.6% of patients were satisfied with SA. No cases of conversion from SA to GA occurred.

CONCLUSION

fURS can be performed safely and efficiently under SA, taking into account a few details of the technique. Patients' satisfaction with SA is very high, and complications are rare. Although SA is usually adopted in unfit patients for GA, it may be considered as a viable alternative in fit patients.

Prevention and Management of Infectious Complications of Retrograde Intrarenal Surgery

Kidney stone disease (KSD) is a commonly encountered ailment in urologic practice. Urinary tract infection (UTI) is commonly associated with KSD, both as an etiology (e.g., struvite and carbonate apatite stones), and as a complication (i.e., obstructive pyelonephritis and post-operative UTI). Indeed, a significant portion of the economic burden of KSD is skewed toward stones associated with infection. UTI is the most common post-operative complication related to stone intervention with progression to urosepsis as a rare but serious consequence. Risk for infection is influenced by a variety of factors including co-morbid conditions, anatomic abnormalities, prior surgical procedures, and local anti-microbial susceptibility. Understanding these risks and the proper steps to mitigate them is an essential component in reducing post-operative morbidity and mortality. Retrograde intrarenal surgery is routinely used for the treatment of KSD. The objective of this review article is to examine the current literature and guidelines for the prevention and management of stone-related infectious complications associated with retrograde intrarenal surgery. Special attention will be given to the incidence, etiology, and antibiotic prophylaxis choice in the management of stone-related infections. Intraoperative risk mitigation techniques will be discussed in conjunction with the management of post-operative infections. Antibiotic stewardship and the potential benefits of reduced empiric antibiotic treatment will also be discussed.

Risk Factors for Urosepsis After Ureteroscopy for Stone Disease: A Systematic Review with Meta-Analysis

Introduction: Urosepsis is a serious potential complication of ureteroscopic procedures for stone disease, yet the risk factors for this complication are not well characterized. The purpose of this systematic review with meta-analysis was to identify potential risk factors for urosepsis after ureteroscopy (URS) for stone disease. Materials and Methods: We performed systematic searches of Medline, Embase, and the Cochrane Central Register of Controlled Trials for studies reporting at least one prospectively defined risk factor for urosepsis after URS. Studies that only reported rates of isolated fever, urinary tract infection (UTI), or pooled infectious complications were excluded. The risk factors evaluated in this review were age, sex, body mass index, diabetes mellitus, ischemic heart disease, recent UTI, pyuria, hydronephrosis, stone history, stone size, preoperative stent placement, preoperative positive urine culture, and procedure time. A random effects meta-analysis model with inverse variance weighting was used where the statistic of interest was the odds ratio for dichotomous variables and the mean difference for continuous outcomes. Results: In 13 studies (5 prospective) with 5597 patients, the pooled incidence of postoperative urosepsis was 5.0% (95% confidence interval: 2.4-8.2). Six risk factors were statistically associated with increased postoperative urosepsis risk-preoperative stent placement (odds ratio = 3.94, p < 0.001, 6 studies), positive preoperative urine culture (odds ratio = 3.56, p < 0.001, 6 studies), ischemic heart disease (odds ratio = 2.49, p = 0.002, 2 studies), older age (mean difference = 2.7 years, p = 0.002, 6 studies), longer procedure time (mean difference = 9 minutes, p = 0.02, 1 study), and diabetes mellitus (odds ratio = 2.04, p = 0.04, 6 studies). Conclusions: Current evidence suggests that among patients undergoing URS for treatment of stone disease, the risk of postoperative urosepsis was 5.0%. Older age, diabetes mellitus, ischemic heart disease, preoperative stent placement, a positive urine culture, and longer procedure time were associated with increased postoperative urosepsis risk. These results will assist urologists with preoperative risk stratification before ureteroscopic procedures.

Urinary Tract Infection After Robot-assisted Laparoscopic Pyeloplasty: Are Urine Cultures and Antibiotics Helpful?

OBJECTIVE

To evaluate how variations in peri-operative urine culture (UCx) and antibiotic prophylaxis utilization following robot assisted laparoscopic pyeloplasty (RALP) affect post-RALP urinary tract infection (UTI) rates in children, then use data to generate a standardized care pathway.

METHODS

Patients undergoing RALP at a single institution from January 2014 to October 2018 were retrospectively reviewed. Patients with vesicoureteral reflux, neurogenic bladder, intermittent catheterization, <=2 months follow-up after stent removal, or age >=18 years were excluded. UCx use, UCx results, and pre- and post-RALP antibiotic use were recorded. The primary outcome was symptomatic UTI, tracked until 60 days after stent removal. UTI was defined as presence of fever or urinary symptoms, a positive UCx with >=10,000 colony forming units of one uropathogen, and a positive urinalysis.

RESULTS

A total of 152 patients were included (72% male [73% circumcised], 61% white, and 23% Hispanic). One underwent a re-operative pyeloplasty, yielding 153 encounters. Eight patients (5.2%; 95% CI 1.7-8.7%) developed post-RALP UTI. Uncircumcised status and use of pre-operative prophylactic antibiotics were associated with post-RALP UTI (P = .03 and P < .01, respectively). Use of post-RALP antibiotics, whether prophylactic or therapeutic, was not associated with lower UTI rates (P = .92). Positive pre-RALP UCx and positive intra-operative stent removal UCx were associated with higher UTI rates (P = .03 and P < .01, respectively).

CONCLUSION

UTI occurred in 5.2% of our cohort of >150 patients. As post-RALP antibiotic use was not associated with lower UTI rates, prophylactic antibiotics may be reserved for patients with risk factors. A standardized care pathway could safely reduce unnecessary utilization of UA/UCx and antibiotics.

[Bacteriological correlation of urinary stones and preoperative urine culture: Is there a significant impact on postoperative infectious risk? (Moroccan experience)]

AIM

The objectives of this study were to evaluate the impact of preoperative urine culture and the infected nature of stones on the occurrence of postoperative urinary sepsis.

MATERIAL AND METHODS

A prospective monocentric study included 29 patients operated on for urolithiasis between January and June 2018.

RESULTS

Postoperative urinary sepsis was observed in 4 patients (14%). Urinary colonization rate on preoperative CBU exam was 27.6% (8 of 29) while the rate of colonized stones was 31% (9 of 29). The occurrence of urinary sepsis was observed in 37.5% (3 of 8) of patients with urinary colonization, compared to 44.4% of patients with colonized stones (4 of 9). By comparing the bacteriological results observed during sepsis, the germs isolated in postoperative urine were the same found in the culture of stones. The chemical nature of the colonized stones was mainly calcium oxalate (monohydrate, dihydrate) P=0.02. There was a statistically significant correlation between the preoperative urine culture, the bacteriological culture of stones and the postoperative urinary sepsis (P=0.05, P=0.005) respectively.

CONCLUSION

Our study demonstrated a strong association between the bacteriological culture of stones and postoperative urinary sepsis superior to preoperative urine culture. It makes it possible to anticipate the occurrence of sepsis in patients requiring many endoscopic treatments. However, several multicentric prospective series may prove necessary to validate these results.

LEVEL OF EVIDENCE

3.