[Prognostic factors for severe infection after flexible ureteroscopy: Clinical interest of urine culture the day before surgery?]

Understanding the Role of Ureteral Access Sheath in Preventing Post-Operative Infectious Complications in Stone Patients Treated with Ureteroscopy and Ho:YAG Laser Lithotripsy: Results from a Tertiary Care Referral Center

INTRODUCTION AND OBJECTIVES

The use of ureteral access sheaths (UAS) limits the irrigation-induced increase in intrarenal pressure during ureteroscopy (URS). We investigated the relationship between UAS and rates of postoperative infectious complications in stone patients treated with URS.

MATERIALS AND METHODS

Data from 369 stone patients treated with URS from September 2016 to December 2021 at a single institution were analyzed. UAS (10/12 Fr) placement was attempted in case of intrarenal surgery. The chi-square test was used to assess the relationship between the use of UAS and fever, sepsis, and septic shock. Univariable and multivariable logistic regression analyses tested the association of patients' characteristics and operative data and the rate of postoperative infectious complications.

RESULTS

Full data collection of 451 URS procedures was available. Overall, UAS was used in 220 (48.8%) procedures. As for postoperative infectious sequalae, we recorded fever (n = 52; 11.5%), sepsis (n = 10; 2.2%), and septic shock (n = 6; 1.3%). Of those, UAS was not used in 29 (55.8%), 7 (70%), and 5 (83.3%) cases, respectively (all p > 0.05). At multivariable logistic regression analysis, performing URS without UAS was not associated with the risk of having fever and sepsis, but it increased the risk of septic shock (OR = 14.6; 95% CI = 1.08-197.1). Moreover, age-adjusted CCI score (for fever-OR = 1.23; 95% CI = 1.07-1.42, sepsis-OR = 1.47; 95% CI = 1.09-1.99, and septic shock-OR = 1.61; 95% CI = 1.08-2.42, respectively), history of fever secondary to stones (for fever-OR = 2.23; 95% CI = 1.02-4.90) and preoperative positive urine culture (for sepsis-OR = 4.87; 95% CI = 1.12-21.25) did emerge as further associated risk factors.

CONCLUSIONS

The use of UAS emerged to prevent the onset of septic shock in patients treated with URS, with no clear benefit in terms of fever and sepsis. Further studies may help clarify whether the reduction in fluid reabsorption load mediated by UAS is protective against life-threatening conditions in case of infectious complications. The patients' baseline characteristics remain the main predictors of infectious sequelae in a clinical setting.

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.

Single-use flexible ureteroscopes: update and perspective in developing countries. A narrative review

Flexible ureteroscopy is a well-established method for treatment of urinary stones but flexible ureteroscopes are expensive and fragile devices with a very limited lifetime. Since 2006 with the advent of digital flexible ureteroscopes a great evolution has occurred. The first single-use flexible ureteroscope was launched in 2011 and new models are coming to the market. The aim of this article is to review the characteristics of these devices, compare their results with the reusable devices and evaluate the cost-benefits of adopting single-use flexible ureteroscopes in developing countries.

Risk Factors of Urinary Tract Infection After Ureteral Stenting in Patients with Renal Colic During Pregnancy

Introduction: To investigate risk factors associated with urinary tract infection (UTI), following ureteral stenting, for patients with renal colic during pregnancy. Patients and Methods: Patients with renal colic during pregnancy who underwent ureteral stenting in The First Affiliated Hospital of Guangzhou Medical University between 2009 and 2019 were examined retrospectively. Ureteral stenting patients who had UTIs after hospital discharge and before delivery were classified as the infected group. Multivariate logistic regression analysis was used to assess the risk factors associated with UTI after ureteral stenting. Results: A total of 102 patients were enrolled into the study. Mean age was 30 years (interquartile range [IQR]: 26-33 years) and mean gestation age was 22 weeks (IQR: 18-28 weeks). UTI occurred in 21 patients (20.6%). Compared with noninfected patients, infected patients had a higher rate of positive urine culture (52.4% vs 13.6%, p = 0.000), kidney stones ≥10 mm (81% vs 35.8%, p = 0.000), residual stones after ureteral stenting (71.4% vs 43.2%, p = 0.021), and different surgical indications and gestational ages (18 vs 23 weeks, p = 0.00). Multifactor analysis showed that gestational age, positive urine culture (odds ratio [OR] = 6.233, 95% confidence interval [CI]: 1.830-21.227), and stones ≥10 mm (OR = 0.124, 95% CI: 0.031-0.495) were independent risk factors for UTI after ureteral stenting in patients with renal colic. In the infection group, Escherichia coli was the most commonly found organism (47.4%). Conclusions: Gestational age, positive urine culture before surgery, and stone ≥10 mm were risk factors for UTI after ureteral stenting in pregnant patients with renal colic. E. coli was the main pathogen of UTI after this procedure. Preoperative anti-infection treatment needs to be based on drugs that are sensitive to E. coli.

[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.

Predictors of emergency department attendance following ureterorenoscopy for urolithiasis

BACKGROUND

We sought to determine the rate of emergency department (ED) attendance for complications after ureterorenoscopy (URS) for stone disease and to identify risk factors for ED attendance after URS.

METHODS

An analysis of all patients undergoing URS over 12 months at a single institution was performed. Patient demographics, preoperative and intraoperative variables associated with postoperative complications and subsequent ED attendance were collected. Logistic regression analyses were performed to determine predictors of URS complications presenting to ED.

RESULTS

In total, 202 ureteroscopies were performed on 142 patients for urolithiasis. The mean age was 50.73 ± 13.93 and 66% were male. The incidence of re-presentation to ED was 14.8% (n = 30). Patients presented with postoperative pain (n = 10; 4.95%), pyrexia (n = 9; 4.46%), urinary tract infection (UTI) (n = 7, 3.47%), haematuria (n = 3, 1.49%) and urosepsis (n = 1; 0.5%). Significant risk factors for ED attendance included preoperative stent dwell time > 30 days (P = 0.004), recently treated positive preoperative urine culture (P < 0.0001), stone size ≥ 13 mm (P = 0.043), stone location mid-ureter (P = 0.036) and female gender (P = 0.005). The following factors did not predict ED attendance, stent omission, access sheath utilization and operation duration.

CONCLUSION

Risk factors for ED attendance after URS include prolonged pre-stent dwell time, stone size ≥ 13 mm, treatment for a positive preoperative urine culture, mid-ureteric stone location and female gender. Urologists should be aware of these findings to decrease the risk of emergency re-presentation after elective URS surgery.

A comprehensive literature-based equation to compare cost-effectiveness of a flexible ureteroscopy program with single-use versus reusable devices

PURPOSE

To critically review all literature concerning the cost-effectiveness of flexible ureteroscopy comparing single-use with reusable scopes.

MATERIALS AND METHODS

A systematic online literature review was performed in PubMed, Embase and Google Scholar databases. All factors potentially affecting surgical costs or clinical outcomes were considered. Prospective assessments, case control and case series studies were included.

RESULTS

741 studies were found. Of those, 18 were duplicated and 77 were not related to urology procedures. Of the remaining 646 studies, 59 were considered of relevance and selected for further analysis. Stone free and complication rates were similar between single-use and reusable scopes. Operative time was in average 20% shorter with digital scopes, single-use or not. Reusable digital scopes seem to last longer than optic ones, though scope longevity is very variable worldwide. New scopes usually last four times more than refurbished ones and single-use ureterorenoscopes have good resilience throughout long cases. Longer scope longevity is achieved with Cidex and if a dedicated nurse takes care of the sterilization process. The main surgical factors that negatively impact device longevity are lower pole pathologies, large stone burden and non-use of a ureteral access sheath. We have built a comprehensive fi nancial costeffective decision model to fl exible ureteroscope acquisition.

CONCLUSIONS

The cost-effectiveness of a fl exible ureteroscopy program is dependent of several aspects. We have developed a equation to allow a literature-based and adaptable decision model to every interested stakeholder. Disposable devices are already a reality and will progressively become the standard as manufacturing price falls.

Next-Generation Single-Use Ureteroscopes: An In Vitro Comparison

INTRODUCTION

Single-use ureteroscopes have been gaining popularity in recent years. We compare the optics, deflection, and irrigation flow of two novel single-use flexible ureteroscopes-the YC-FR-A and the NeoFlex-with contemporary reusable and single-use flexible ureteroscopes.

METHODS

Five flexible ureteroscopes, YC-FR-A (YouCare Tech, China), NeoFlex (Neoscope, Inc., USA), LithoVue (Boston Scientific, USA), Flex-Xc (Karl Storz, Germany), and Cobra (Richard Wolf, Germany), were assessed in vitro for image resolution, distortion, field of view, depth of field, color representation, and grayscale imaging. Ureteroscope deflection and irrigation were also compared.

RESULTS

The YC-FR-A showed a resolution of 5.04 lines/mm and 4.3% image distortion. NeoFlex showed a resolution of 17.9 lines/mm and 14.0% image distortion. No substantial difference was demonstrated regarding the other optic characteristics between the two. Across all tested ureteroscopes, single-use or reusable, the digital scopes performed best with regard to optics. The YC-FR-A had the greatest deflection at baseline, but lacks two-way deflection. The NeoFlex had comparable deflection at baseline to reusable devices. Both ureteroscopes had substantial loss of deflection with instruments in the working channel. The YC-FR-A had the greatest irrigation rate. The NeoFlex has comparable irrigation to contemporary ureteroscopes.

CONCLUSIONS

The YouCare single-use fiberoptic flexible ureteroscope and NeoFlex single-use digital flexible ureteroscope perform comparably to current reusable ureteroscopes, possibly making each a viable alternative in the future. Newer YouCare single-use flexible ureteroscopes with a digital platform and two-way deflection may be more competitive, while the NeoFlex devices are undergoing rapid improvement as well. Further testing is necessary to validate the clinical performance and utility of these ureteroscopes, given the wide variety of single-use devices under development.

Analysis of Factors' Association with Risk of Postoperative Urosepsis in Patients Undergoing Ureteroscopy for Treatment of Stone Disease

INTRODUCTION

To investigate which patient, stone, infective, and surgical factors were most likely to increase the risk of postoperative urosepsis within 28 days of ureteroscopy (URS) and laser stone fragmentation for ureteral or renal stones.

METHODS

Data were collected prospectively in a single National Health Service institution. A logistic regression model was used to assess the association of factors with postoperative urosepsis. Two matched-pair analyses were used to assess the risk of postoperative urosepsis in patients with (a) an emergency presentation to hospital with urosepsis in the 90 days preceding URS and (b) a positive midstream sample of urine (MSSU) identified, but who were asymptomatic at preoperative assessment, who then received an appropriate course of antibiotics.

RESULTS

Four hundred sixty-two consecutive patients were included in the study. Thirty-four patients (7.4%) had an episode of urosepsis within 28 days of their operation. A positive preoperative MSSU was significantly associated with postoperative urosepsis on multivariable analysis, despite appropriate treatment with a preoperative course of antibiotics: odds ratio (OR) 4.88, 95% confidence interval (CI) 2.11, 11.31, p < 0.001. The presence of diabetes mellitus, presence of ischemic heart disease, patient American Society of Anesthesiologists score, same-session bilateral URS, and stone volume were the other variables significantly associated with postoperative infection on univariable analysis, but these ceased to be significantly associated on multivariable analysis. Subgroup analysis found that a positive MSSU in both patients with a preoperative ureteral stent and those without was significantly associated with postoperative urosepsis, however, the OR was much lower for the stented group (OR 3.23 vs OR 16.67). On matched-pair analysis, patients with a positive preoperative MSSU were significantly more likely to have postoperative urosepsis compared to controls (OR 17.46, 95% CI 2.18, 139.80, p = 0.007). There was no significant difference in the OR of postoperative urosepsis in patients who had a preceding urine infection requiring hospital admission in the 90 days preceding URS (OR 0.60, 95% CI 0.19, 1.92, p = 0.39).

CONCLUSIONS

Positive preoperative MSSU was significantly associated with postoperative urosepsis by logistic regression and matched-pair analysis. These higher risk patients should be counseled appropriately before surgery, and should be the focus of vigilant postoperative monitoring. The study suggests particular caution in patients with a positive preoperative MSSU without a preoperative ureteral stent.