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

The Application of Next-Generation Sequencing in Preoperative Evaluation for Urologic Stone Surgery

Introduction: Next-generation sequencing (NGS) is a new molecular technique for identifying microorganisms. Treating bacteriuria in patients undergoing stone removal procedures is important for preventing postoperative urinary tract infection (UTI). The objective of this study is to assess the usefulness of preoperative urine NGS testing by comparing NGS with standard urine culture in predicting postoperative UTI after ureteroscopic lithotripsy (URSL) and percutaneous nephrolithotomy (PCNL). Materials and Methods: This prospective study was conducted from February 16, 2022, to January 11, 2024. Sixty subjects who underwent URSL or PCNL were included. Preoperative voided urine samples were collected for urine culture and tested by MicroGenDX for urine polymerase chain reaction (PCR) and urine NGS. Stone specimens obtained intraoperatively were also sent for stone culture and MicrogenDx. Patients were monitored for 4 weeks post-operation for recording clinical outcomes related to infections and complications. Results: Twenty-six (43.3%) male and 34 (56.7%) female participants were included. Twenty-six (43.3%) patients underwent PCNL (15 standard PCNL and 11 mini PCNL), and 34 (56.7%) underwent URSL. Standard urine culture identified positive results in 26 cases (43.3%), PCR for 17 cases (28.3%), and NGS for 31 cases (51.7%). The overall postoperative UTI rate was 6 (10%). Standard urine culture demonstrated a sensitivity of 50%, specificity of 57.4%, and accuracy of 56.7%. Positive predictive value (PPV) was notably poor at 11.5%. Urine NGS showed a higher sensitivity of 83.3%, specificity of 53.7%, accuracy of 55%, and PPV of 16.7%. Conclusion: Urine NGS significantly improves the sensitivity of detecting microorganisms in preoperative urine compared with standard urine culture. Despite its high sensitivity and capability to identify nonculturable bacteria, using NGS alongside standard urine culture is recommended. This parallel approach harnesses the strengths of both methods. Integrating NGS into standard practice could elevate the quality of care, especially for patients at high risk of UTIs, such as those undergoing invasive stone removal procedures.

Using fosfomycin to prevent infection following ureterorenoscopy in response to shortage of cephalosporins: a retrospective preliminary study

BACKGROUND

In 2019, the shortage of cefazolin led to the demand for cefotiam and cefmetazole exceeding the supply. The Department of Nephro-urology at Nagoya City University Hospital used fosfomycin as a substitute for perioperative prophylaxis. This retrospective preliminary study evaluated the efficacy of fosfomycin and cefotiam for preventing infections following ureterorenoscopy.

METHODS

The study included 182 patients who underwent ureterorenoscopy between January 2018 and March 2021). Perioperative antibacterial treatment with fosfomycin (n = 108) or cefotiam (n = 74) was administered. We performed propensity score matching in both groups for age, sex, preoperative urinary catheter use, and preoperative antibiotic treatment.

RESULTS

The fosfomycin and cefotiam groups (n = 69 per group) exhibited no significant differences in terms of patients' median age, operative duration, preoperative urine white blood cell count, preoperative urine bacterial count, and the rate of preoperative antibiotic treatment. In the fosfomycin and cefotiam groups, the median duration of postoperative hospital stay was 3 and 4 days, respectively; the median maximum postoperative temperature was 37.3 °C and 37.2 °C, respectively. The fosfomycin group had lower postoperative C-reactive protein levels and white blood cell count than the cefotiam group. However, the frequency of fever > 38 °C requiring additional antibiotic administration was similar.

CONCLUSIONS

During cefotiam shortage, fosfomycin administration enabled surgeons to continue performing ureterorenoscopies without increasing the complication rate.

Recurrent UTI in Women-Risk Factors and Management

Urinary tract infections (UTIs) are common in women; more than 50% of women will be diagnosed with a UTI in her lifetime. Many of these women will go on to develop recurrent UTI. Nevertheless, evidence-based prevention of recurrent UTI is under-utilized. Here, the authors provide detailed practical advice on UTI prevention with a thorough review of the evidence. Non-antibiotic prevention measures discussed include increased fluid intake, vaginal estrogen therapy, methenamine, and cranberry. Antibiotic prophyalxis for carefully selected patients is also discussed.

Urinary Tract Infection Predictors in Patients Undergoing Retrograde IntraRenal Surgery for Renal Stones: Does the Instrument Make the Difference?

Background: Retrograde intrarenal surgery (RIRS) using flexible ureterorenoscopes is a cornerstone approach for renal stone removal, yet it carries a significant risk of postoperative urinary tract infection (UTI). With the emergence of single-use ureterorenoscopes, there is growing interest in their potential to mitigate this risk. This study aimed to compare the postoperative infection rates between single-use and multi-use ureterorenoscopes in RIRS procedures and to identify predictors of postoperative UTI. Methods: Data were collected from 112 consecutive patients who underwent RIRS for renal stones between March 2022 and September 2023. Peri-operative variables including age, gender, body mass index (BMI), stone size, stone location, type of ureterorenoscope, Hounsfield Units (HU), pre-operative hydronephrosis, laboratory analysis, and operative time were evaluated. Univariate and multivariate logistic regression analyses were performed to assess the predictors of postoperative UTI. Results: Of the cohort, 77 surgeries (68.7%) utilized multi-use ureterorenoscopes, while 35 (31.3%) utilized single-use devices. Stone diameter, number of stones, type of ureterorenoscope, and operative time were significant predictors of postoperative UTI in the univariate analysis. Multivariable logistic regression showed that operative time (OR, 1.3; 95% CI, 0.55-0.99; p = 0.03) and type of ureterorenoscope (multi-use vs. single-use) (OR, 1.14; 95% CI, 1.08-1.2; p < 0.001) were independent predictors of postoperative UTI. Conclusions: In conclusion, this study highlights that multi-use ureterorenoscopes and prolonged operative time are associated with an increased risk of postoperative UTI in RIRS procedures. Careful pre-operative evaluation and meticulous patient selection are essential to minimize the occurrence of postoperative UTIs and optimize patient outcomes in RIRS for renal stones.

Influence of preoperative urine culture and bacterial species on urogenital sepsis after ureteral flexible lithotripsy in patients with upper urinary tract stones

Objective

This retrospective study aims to identify risk factors for urogenic sepsis in patients with upper urinary tract stones following ureteral flexible lithotripsy (FURL). Additionally, we analyze the clinical characteristics of bacterial infections post-surgery.

Methods

A total of 759 patients who underwent FURL at the Urology Department of Zunyi Medical University were included. Univariate and multivariate Logistic regression analyses were conducted to identify independent risk factors for urogenic sepsis post-FURL. The distribution of bacteria based on preoperative urine cultures was also analyzed. Statistical analysis was performed using R4.2.2 software.

Results

Of the 759 patients, positive preoperative urine culture, urine nitrite positivity, urine white blood cell count (WBC) ≥ 200 cells/μL, residual stones, and neutrophil-to-lymphocyte ratio (NLR) were found to be independent risk factors for urogenic sepsis after FURL. Among the 164 patients with positive preoperative urine cultures, 32 developed urogenic sepsis post-surgery, with 68.75% having positive preoperative cultures. The leading pathogens causing postoperative urogenic sepsis were Escherichia coli (E. coli), Enterococcus faecium, Proteus mirabilis, and Klebsiella pneumoniae. The probabilities of progression to urogenic sepsis were as follows: E. coli 19% (n = 12), Enterococcus faecium 43% (n = 3), Proteus mirabilis 33.3% (n = 1), and Klebsiella pneumoniae 33.3% (n = 1). The ages of affected patients were 47.17 ± 13.2, 53.7, 41, and 79 years, respectively. Rates of comorbid diabetes were 36.4, 66.7, 50, 100%, with nitrite positivity rates at 72.7, 33.3, 50, 0%. Ten female patients were infected with E. coli, while patients infected with Klebsiella pneumoniae had an NLR of 7.62.

Conclusion

Positive preoperative urine culture, urine nitrite positivity, urine WBC ≥ 200 cells/μL, residual stones, and NLR are independent risk factors for urogenic sepsis after FURL. Escherichia coli is the predominant pathogen post-FURL, with notable female prevalence and nitrite-positive urine in infections. Enterococcus faecium infections are associated with diabetes.

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.

Confirmation of negative urine culture status after appropriate antibiotic treatment prior to endourological stone procedures: Is it really necessary?

To evaluate the necessity of confirmation for a negative urine culture test outcome after an appropriate antibiotic regimen for urinary tract infection (UTI) prior to endoscopic stone removal procedures. 170 cases receiving an appropriate antibiotic treatment for culture proven UTI based on test outcomes before endoscopic stone removal were evaluated in two groups: Group 1 (n = 85) Patients in whom a second urine culture test was performed to ensure "negative urine culture" status prior to the procedures after receiving antibiotic therapy and Group 2 (n = 85). Patients receiving the same antibiotic therapy without any additional urine culture test before the procedures. Cases were comparatively evaluated with respect to the statistical significance of post-operative infective complications (fever, sepsis), duration of hospital stay and readmission rates during early post-operative period. Our findings demonstrated no significant difference regarding the rate of infective complications (presence of fever, incidence of septic findings), hospitalization period and readmission rates between the two groups. Although the presence of a negative urine status has been confirmed by urine culture test in group 1 cases, no additional urine culture test was performed with this aim in group 2 cases (negative urine culture was confirmed only with urinalysis) and the outcomes regarding the infective problems were found to be similiar. Our current findings indicate that a second urine culture test may not be a "must" if the patients receive an appropriate antibiotic regimen based on the sensitivity test outcomes for a reasonable time period.

2022 Recommendations of the AFU Lithiasis Committee: Ureteroscopy and ureterorenoscopy

Technical advances, including miniaturization, have improved the deflection and optical performance of the ureteroscopes, and the availability of dedicated disposable devices have led to their increasing use for kidney and ureteral stone management. Ureterorenoscopy brings diagnostic evidence through the endoscopic description of stones and renal papillary abnormalities. Currently, intracorporeal lithotripsy during ureterorenoscopy is based on laser sources. Routine ureteral stenting is not necessary before ureterorenoscopy, especially because preoperative stenting for>30 days is considered as an independent risk factor of infection. Ureteral access sheaths allow the easy and repeated access to the upper urinary tract and thus facilitate ureterorenoscopy. Their use improves vision, decreases intrarenal pressure, and possibly reduces the operative time, but they may cause ureteral injury. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether or not the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis [EAU 2022]) and their adaptability to the French context.

In vivo ureteroscopic intrarenal pressures and clinical outcomes: a multi-institutional analysis of 120 consecutive patients

OBJECTIVES

To evaluate the pressure range generated in the human renal collecting system during ureteroscopy (URS), in a large patient sample, and to investigate a relationship between intrarenal pressure (IRP) and outcome.

PATIENTS AND METHODS

A prospective multi-institutional study was conducted, with ethics board approval; February 2022-March 2023. Recruitment was of 120 consecutive consenting adult patients undergoing semi-rigid URS and/or flexible ureterorenoscopy (FURS) for urolithiasis or diagnostic purposes. Retrograde, fluoroscopy-guided insertion of a 0.036-cm (0.014″) pressure guidewire (COMET™ II, Boston Scientific, Marlborough, MA, USA) to the renal pelvis was performed. Baseline and continuous ureteroscopic IRP was recorded, alongside relevant operative variables. A 30-day follow-up was completed. Descriptive statistics were applied to IRP traces, with mean (sd) and maximum values and variance reported. Relationships between IRP and technical variables, and IRP and clinical outcome were interrogated using the chi-square test and independent samples t-test.

RESULTS

A total of 430 pressure traces were analysed from 120 patient episodes. The mean (sd) baseline IRP was 16.45 (5.99) mmHg and the intraoperative IRP varied by technique. The mean (sd) IRP during semi-rigid URS with gravity irrigation was 34.93 (11.66) mmHg. FURS resulted in variable IRP values: from a mean (sd) of 26.78 (5.84) mmHg (gravity irrigation; 12/14-F ureteric access sheath [UAS]) to 87.27 (66.85) mmHg (200 mmHg pressurised-bag irrigation; 11/13-F UAS). The highest single pressure peak was 334.2 mmHg, during retrograde pyelography. Six patients (5%) developed postoperative urosepsis; these patients had significantly higher IRPs during FURS (mean [sd] 81.7 [49.52] mmHg) than controls (38.53 [22.6] mmHg; P < 0.001).

CONCLUSIONS

A dynamic IRP profile is observed during human in vivo URS, with IRP frequently exceeding expected thresholds. A relationship appears to exist between elevated IRP and postoperative urosepsis.

Optimal Dwelling Time for Ureteral Stents Placed for Passive Dilation after Impassable Ureteroscopy

INTRODUCTION

The aim of the study was to determine the correlation between the dwelling time for a ureteral stent placed for passive dilation after impassable ureteroscopy and success and complications.

METHODS

A retrospective evaluation was made of patients who underwent stent placement after impassable ureteroscopy and a repeat ureteroscopy due to kidney stones. A total of 161 patients were included in the study between 2015 and 2022. Demographic, clinical, preoperative, and perioperative data were collected. Logistic regression analyses were performed on the data showing a significant difference in the univariate analyses performed to determine the predictive factors of ureteroscopy after the stent dwelling period in terms of stone-free status and perioperative complications.

RESULTS

Stone-free status was achieved in 110 (68.3%) of 161 patients, and perioperative complications were observed in 41 (25.4%). Factors that affected the stone-free status were determined as the dwelling time and the S-ReSC score, while factors affecting perioperative complications were the stent dwelling time and the operation time. The stone-free rates were observed to increase from 46.4% in the first 2 weeks to 72.9% after the 2nd week, an increase of 1.5-fold. Perioperative complications were determined at the rate of 17.5% during the first 5 weeks and increased 2.1-fold to 37.5% after the 5th week.

CONCLUSION

It can be recommended that great care is taken during the stent dwelling period and ureteroscopy should be performed within 5 weeks (14-35 days) but no earlier than 2 weeks, so as not to affect the success of the procedure.

Use of artificial intelligence for sepsis risk prediction after flexible ureteroscopy: a systematic review

INTRODUCTION

flexible ureteroscopy is a minimally invasive surgical technique used for the treatment of renal lithiasis. Postoperative urosepsis is a rare but potentially fatal complication. Traditional models used to predict the risk of this condition have limited accuracy, while models based on artificial intelligence are more promising. The objective of this study is to carry out a systematic review regarding the use of artificial intelligence to detect the risk of sepsis in patients with renal lithiasis undergoing flexible ureteroscopy.

METHODS

the literature review is in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The keyword search was performed in MEDLINE, Embase, Web of Science and Scopus and resulted in a total of 2,496 articles, of which 2 met the inclusion criteria.

RESULTS

both studies used artificial intelligence models to predict the risk of sepsis after flexible uteroscopy. The first had a sample of 114 patients and was based on clinical and laboratory parameters. The second had an initial sample of 132 patients and was based on preoperative computed tomography images. Both obtained good measurements of Area Under the Curve (AUC), sensitivity and specificity, demonstrating good performance.

CONCLUSION

artificial intelligence provides multiple effective strategies for sepsis risk stratification in patients undergoing urological procedures for renal lithiasis, although further studies are needed.

Single-dose fosfomycin could prevent infectious complications after retrograde intrarenal surgery: A prospective study

BACKGROUND

In this study, we aimed to show the protective effect of a single-dose Fosfomycin from infective complications against the standard usage of cephalosporine before retrograde intrarenal surgery.

MATERIAL

A total of 186 patients who underwent retrograde intrarenal surgery between 2020 and 2021, included the study. Patients were divided into two groups: group 1(n=49), patients who received an oral dose of 3g Fosfomycin tromethamine powder administered 4-6h before the operation; and group 2 (n=137): patients who received Cephalosporin 30min before surgery and an additional dose 6h after surgery.

RESULTS

The median age and stone size were significantly higher in the cephalosporin group (P=0.006 and P=0.008, respectively). There was no statistically significant difference between the groups in terms of postoperative fever and postoperative UTI (P=0.408 and P=0.438). Additionally, no patient developed sepsis. and no adverse event was seen in either group. Preoperative urinary tract infection (UTI) and previous Extracorporeal Shock Wave lithotripsy (ESWL) were independent risk factors and increased postoperative infectious complications (O.R. 2.929 95% C.I. 0.723, P<0.001, and O.R. 2.860 95% C.I. 0.985, P=0.004, respectively).

CONCLUSION

Infectious is still one of the important complications after RIRS, and preoperative UTI is an independent risk factors for infections. Fosfomycin monotherapy could be sufficient and is also effective in patients with preoperative culture positive.

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.

Comparison between Retrograde Flexible Ureteroscopy and Percutaneous Nephrolithotomy for the Treatment of Renal Stones of 2-4 cm

Background and objectives: Renal stones are widespread, with a lifetime prevalence of 10% in adults. Flexible ureteroscopy enables urologists to treat lower calyx stones or even complex renal stones through the natural orifice and achieve an acceptable stone-free rate. Hence, we analyzed the effectiveness and safety of FURS versus PCNL in treating renal stones between 20 and 40 mm in diameter. Materials and methods: We retrospectively analyzed 250 consecutive patients with large renal solitary stones (stone burden between 2 and 4 cm) from 1 January 2019 to 31 December 2020. The patients were divided into two groups: group 1 (125 patients), in which the patients were treated by a retrograde flexible ureteroscopic approach, and group 2 (125 patients), in which we used percutaneous nephrolithotomy. Stone characteristics and anatomical data were observed based on the computed tomography (CT) and/or KUB (Kidney-ureter-Bladder) radiography imaging archive. Results: The mean stone burden was 26.38 ± 4.453 mm in group 1 and 29.44 ± 4.817 mm in group 2. The stone-free rate after the first ureteroscopy was higher for the PNL(percutaneous nephrolithotomy) group (90.4%) than the F-URS group (68%). After two sessions of ureteroscopy, the SFR was 88.8% in the first group, and after three procedures, the SFR rose to 95.2%. The overall complication rate was higher in group 1 than in group 2 (18.4% vs. 16.8%), but without statistical relevance (p > 0.5). Furthermore, we encountered more grade III and IV complications in the PNL group (8.8% vs. 4.8%, p < 0.05). Conclusion: Flexible ureteroscopy proves to be efficient in treating renal stones over 2 cm. However, the patients must be informed that more than one procedure might be necessary to overcome the entire stone burden.

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

Predictors and Healthcare Utilization of Sepsis Post-Ureteroscopy in a US-Based Population : Results from the Endourological Society TOWER Collaborative

Purpose To investigate the incidence, predictive factors, and healthcare utilization of sepsis post-ureteroscopy (URS) in patients enrolled in commercial insurance plans. Materials and Methods A retrospective claims analysis was conducted using the IBM® MarketScan® commercial database. Patients ≥18 years were included if they had URS between January 2015-October 2019 and developed sepsis within 30 days of URS. Multivariate logistic regression was used to identify various clinical and demographic predictors of sepsis post-URS. All-cause healthcare utilization (i.e., inpatient admissions and intensive care unit stays) and all-cause healthcare costs up to 1 month post-septic event were measured. Results Among the 104,100 URS patients meeting the inclusion criteria, 5.5% developed sepsis. Patients with diabetes (OR=1.52; p<0.0001), older age (age 55-64 versus 18-34; OR=1.35; p<0.0001), baseline sepsis (OR=3.51; p<0.0001), baseline inpatient visits (OR=1.17; p=0.0012), and higher Elixhauser comorbidity scores (OR=1.09; p<0.0001) had a significantly higher likelihood of developing sepsis post-URS. In septic patients, 94.8% required inpatient care and 35% were admitted to the ICU. Mean hospital stay for septic patients was 6.86 days. Average all-cause healthcare cost per patient at 1 month in the septic cohort was $49,625 versus $17,782 in the non-septic cohort indicating an incremental all-cause cost of $31,843 (p<0.0001). Conclusions A total of 5.5% of commercially insured patients undergoing URS developed sepsis post-URS. Diabetes, older age, baseline sepsis, baseline inpatient visit, and higher comorbidity score were all found to be independent predictors of post-URS sepsis. Patients with sepsis post-URS had higher healthcare utilization and costs indicating that sepsis is both a significant clinical and economic event.

Ureteral calculi lithotripsy for single ureteral calculi: can DNN-assisted model help preoperatively predict risk factors for sepsis?

OBJECTIVES

To explore the utility of radiomics and deep learning model in assessing the risk factors for sepsis after flexible ureteroscopy lithotripsy (FURL) or percutaneous nephrolithotomy (PCNL) in patients with ureteral calculi.

METHODS

This retrospective analysis included 847 patients with treatment-naive proximal ureteral calculi who received FURL or PCNL. All participants were preoperatively conducted non-contrast computed tomography scans, and relevant clinical information was meanwhile collected. After propensity score matching, the radiomics model was established to predict the onset of sepsis. A deep learning model was also adapted to further improve the prediction accuracy. Performance of these trained models was verified in another independent external validation set including 40 cases of ureteral calculi patients.

RESULTS

The overall incidence of sepsis after FURL or PCNL was 5.9%. The least absolute shrinkage and selection operator (LASSO) regression analysis revealed 26 predictive variables, with an overall AUC of 0.881 (95% CI, 0.813-0.931) and an AUC of 0.783 (95% CI, 0.766-0.801) in external validation cohort. Judicious adaption of a deep neural network (DNN) model to our dataset improved the AUC to 0.920 (95% CI, 0.906-0.933) in the internal validation. To eliminate the overfitting, external validation was carried out for DNN model (AUC = 0.874 (95% CI, 0.858-0.891)).

CONCLUSIONS

The DNN was more effective than the LASSO model in revealing risk factors for sepsis after FURL or PCNL in single ureteral calculi patients, and females are more susceptible to sepsis than males. Deep learning models have the potential to act as gatekeepers to facilitate patient stratification.

KEY POINTS

• Both the least absolute shrinkage and selection operator (LASSO) and deep neural network (DNN) models were shown to be effective in sepsis prediction. • The DNN model achieved superior prediction capability, with an AUC of 0.920 (95% CI, 0.906-0.933). • DNN-assisted model has potential to serve as a gatekeeper to facilitate patient stratification.

Effectiveness and Safety of Ureteroscopic Lithotripsy in Young, Old-Old, and Oldest Old Patients

Objectives: To investigate the efficacy and safety of ureteroscopic lithotripsy (URSL) in young, old-old, and oldest old patients. Materials and Methods: We enrolled 157 patients who underwent URSL. We divided the patients into young (<65 years), old-old (65-84 years), and oldest old (≥85 years) groups and compared the safety of surgery between young vs old-old and young vs oldest old, separately. Results: In the <65 group, 65 to 85 group, and ≥85 group, respectively, the mean stone diameters were 8.9 ± 4.9, 10.8 ± 7.7, and 11.4 ± 6.3 mm; mean operative time was 76.6 ± 33.1, 86.7 ± 44.7, and 84.0 ± 44.5 min; the stone-free rates were 95.9%, 94.4%, and 96.3%; and the complication rates were 8.2%, 9.8%, and 3.7%. Conclusions: In this study, we showed the feasibility and safety of URSL for elderly people. Although oldest old (≥85 years) people had multiple comorbidities with low performance status, URSL could be performed with acceptable complication rates. Clinical Trial Registration Number: 1809-1.

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.

Can We Identify Patients in Danger of Complications in Retrograde Intrarenal Surgery?-A Retrospective Risk Factors Analysis

Retrograde intrarenal surgery (RIRS) is an innovative and effective method of kidney stones treatment, as it had great influence on the development of endoscopy in urology. The increasing prevalence of urolithiasis together with the rapid development of endourology leads to a rise in the number of procedures related to the disease. Flexible ureteroscopy is constantly being improved, especially regarding the effectiveness and safety of the procedure. The purpose of this study is to evaluate intraoperative and early post-operative complications of RIRS in the treatment of kidney stones. A retrospective analysis of medical records was performed. A series was comprised of 207 consecutive operations performed from 2017 to 2020. Complications occurred in 19.3% (n = 40) of patients. Occurrence according to the Clavien-Dindo scale was: 11.1% for grade I, 5.8% for grade II and 2.4% for grade IV. Infectious complications included SIRS (5.3%, n = 11) and sepsis (2.4%, n = 5). Statistical analysis revealed a correlation between acute post-operative infections and positive midstream urine culture, history of chronic or recurrent urinary tract infections, and increased body mass index (BMI). Furthermore, a significant correlation was observed between pain requiring the use of opioids with BMI over 25. Consequently, history of urinary tract infections, positive pre-operative urine culture, and increased BMI are considered risk factors and require appropriate management.

The active guidewire technique versus standard technique as different way to approach ureteral endoscopic stone treatment

BACKGROUND

One of the greatest challenges in semi-rigid ureteroscopies, for both stones and tumors, is the control of endoscopic vision and the maintenance of low intracavitary liquid pressure. We present a comparison between two operative techniques: in the first method an ordinary guide wire (diameter 0.032'') is used for the procedure; in the second one a 5 Fr ureteral catheter replaces the guidewire (we called it "Active guidewire") Methods We compared 50 semirigid ureteroscopies (sURS) performed using the active guidewire with another 50 procedures conducted with a classic guidewire. We evaluated the difference in operating times, quality of endoscopic vision, periprocedural infections rate and stone-free rate.

RESULTS

The use of active guidewire has considerably reduced the standardized operating times per unit stone-volume by about 39%. Vision quality has improved considerably thanks to the continuous flow in-and-out. Consequently, periprocedural infections decreased (3% vs 30%) and the stone-free rate rose from 86% to 92%.

DISCUSSION AND CONCLUSIONS

Employing an "active guidewire" instead of the standard guidewire, the risk of complications related to high pressures and operating time is considerably lower, as well as better treatment quality thanks to the cleaner vision. This technique has proven to be safe as well as easy to apply, and in our belief is to be preferred whenever the ureter accepts without forcing, both the presence of the catheter and the semi-rigid 7 F ureteroscope.

Optimum duration of ureteral prestenting dwelling time in children undergoing retrograde intrarenal surgery

INTRODUCTION AND OBJECTIVES

Ureteral prestenting before retrograde intrarenal surgery (RIRS) causes passive dilatation of the ureter, improves stone-free rate and is associated with shorter operative time. However, the presence of a ureteric stent may increase the risk for septic complications, which accelerates with increased dwelling time duration. The aim of the present study is to explore the impact of ureteral prestenting timing in a group of children undergoing retrograde intrarenal surgery (RIRS) on perioperative outcomes and complication rates and to define the optimum duration of prestenting dwelling time.

PATIENTS AND METHODS

A retrospective study on 60 children aged less than 14 years, presented with upper tract urinary stones, who were subdivided into two groups: Group 1 and 2, each included 30 children who had undergone RIRS after ureteric stenting for two weeks and four weeks respectively. Success of ureteroscope introduction, operative time, stone free rate (SFR), intraoperative and postoperative complications and number of retreatment procedures after definitive RIRS were recorded and compared between the two treatment groups.

RESULTS

Ureteric access was successfully obtained in all children in both groups. Patients in group 1 and 2 had a SFR of 86.6% and 90%, respectively (p = 0.199). The mean operative time of group 1 and 2 were 56.5 and 52.9 min (p = 0.612). Postoperative UTI rates increased with prolonged dwelling time from 6.7% in group 1 to 30% in group 2. No patient in both groups developed high grade complications.

CONCLUSIONS

Increasing prestenting dwelling time from two to four weeks had no statistically significant effect on the successful ureteroscopic access nor the stone free rate in children undergoing RIRS. Reducing the ureteric stent dwelling time minimizes the rate of postoperative UTI without compromising the success of operative outcomes.

Commentary in response to BMC Urology publication entitled "Infection-related hospitalization following ureteroscopic stone treatment: results from a surgical collaborative"

This Commentary is in response to the BMC Urology publication entitled "Infection-related hospitalization following ureteroscopic stone treatment: Results from a surgical collaborative". This study utilized a registry with prospectively recorded standardized data elements named Reducing Operative Complications from Kidney Stones, part of the Michigan Urological Surgery Improvement Collaborative, to identify risk factors of infection-related hospitalization after ureteroscopy for stone treatment. The study included 1817 primary URS procedures for urinary stones in 11 practices in Michigan. They found 43 patients (2.4%) were hospitalized with an infection-related complication and 3 patients died during their hospitalization (0.2% mortality rate). Just over 20% of patients did not have a pre-operative urinalysis or urine culture, representing a deviation from guideline recommendations. Also, in the hospitalized group, none of the 12 patients (27.9%) who had a positive pre-operative urinalysis or urine culture received pre-operative treatment. A multivariable analysis identified higher Charleston Comorbidity Index, history of recurrent urinary tract infection, increasing stone size, intraoperative complications, and fragments left in-situ as independent risk factors for hospitalization from an infection after ureteroscopy. This commentary discusses caveats to the data as well as short-comings of the study. It also reviews more broadly infection after ureteroscopy, includes findings from similar studies, and highlights guideline recommendations to reduce infection risk.

Antimicrobial Selection for Transurethral Procedures Across the United States: A State-by-State Antibiogram Evaluation

OBJECTIVE

To evaluate optimal regimens for perioperative antimicrobial prophylaxis in transurethral procedures by examining antimicrobial susceptibility patterns in the United States.

MATERIALS AND METHODS

Through several methods, we attempted to attain an antibiogram for each state. We focused on microbes known to cause infections after transurethral surgeries and antibiotics referred to in current or prior recommendations and compared susceptibility rates across states using Kruskal Walis tests and the Dwass, Steel, Critchlow-Fligner tests. We also examined susceptibility to (non-ceftazidime) third generation cephalosporins.

RESULTS

Data is included from 40 states. For each microbe studied, there was significant variability in sensitivity to antibiotics studied. Current first line recommendations for antimicrobial prophylaxis include first generation cephalosporins with 82%, 80%, and 87% mean coverage for E coli, Proteus, and Klebsiella respectively and trimethoprim-sulfamethoxazole with 74%, 80%, and 93% coverage, respectively. Susceptibility to aminoglycosides is 91%, 92%, and 96%, respectively and to third generation cephalosporin, it is 92%, 99%, and 94%.

CONCLUSION

Current first line recommended antimicrobials for prophylaxis in transurethral procedures provide overall poor predicted coverage based on our database of antibiograms. Alternatives exist that have higher predicted susceptibility, though clinical significance of this and risk of resultant antimicrobial resistance is unknown. Urologists should consider local patterns when selecting antimicrobial prophylaxis for their 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.

Percutaneous Nephrolithotomy Can Reduce the Incidence of Sepsis Compared with Flexible Ureteroscopy in Treating Solitary Proximal Ureteral Stone Patients with Positive Urine Culture

Background

Sepsis is a potentially lethal complication for both flexible ureteroscopy (fURS) and percutaneous nephrolithotomy (PCNL). This study is aimed at comparing the sepsis rate after fURS and PCNL and the risk factors for sepsis in patients with solitary proximal ureteral stone.

Methods

We reviewed the data of patients with calculi between 10 mm to 20 mm who underwent fURS or PCNL surgery from Tongji Hospital's database. A total of 910 patients were eligible with 412 fURS cases and 498 PCNL cases. We used univariate analysis and multivariate logistic regression analysis to identify the risk factors for sepsis. Subgroup analysis was performed using logistic regression analysis.

Results

In the cohort, 27 (6.6%) and 19 (3.8%) patients developed sepsis after fURS and PCNL, respectively. Multivariate analysis shows that the risk factors for sepsis are fURS (OR = 3.160, P = 0.004), serum WBC ≥ 10,000 cells/μL (OR = 3.490, P = 0.008), albumin − globulin ratio < 1.2 (OR = 2.192, P = 0.029), positive urine culture (OR = 6.145, P < 0.001), and prolonged operation time (OR = 1.010, P = 0.046). Subgroup analysis was conducted using potential risk factors: stone size, serum WBC, urine culture, and albumin-globulin ratio (AGR). In subgroup of positive urine culture, patients were more likely to develop sepsis after fURS than PCNL.

Conclusions

PCNL may be a better choice than fURS to reduce postoperative sepsis, especially for patients with positive urine culture.

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.

Predictors and Strategies to Avoid Mortality Following Ureteroscopy for Stone Disease: A Systematic Review from European Association of Urologists Sections of Urolithiasis (EULIS) and Uro-technology (ESUT)

CONTEXT

While kidney stone disease is common and ureteroscopy (URS) is perceived as minimally invasive, there is mortality associated with treatment.

OBJECTIVE

The aim of this review was to ascertain the number of mortalities from URS for stone disease over the past three decades, identify relevant patient risk factors and predictors of mortality, and summarise the key recommendations so that similar instances can be avoided, and lessons can be learnt.

EVIDENCE ACQUISITION

A systematic literature search was conducted following Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) methodology for English-language article reporting on data from 1990 to December 2020. Data collated from each study included patient and stone characteristics, number of mortalities, and cause of death.

EVIDENCE SYNTHESIS

Fifteen studies met our inclusion criteria and revealed a total of 72 mortalities from ten countries. The age range of reported patients varied from 21 to 89 yr, with over 60% being above 65 yr of age and 97% with some comorbidity. Based on available data, death reports in females were three times more than those in males. The stone size ranged from 10 to 38 mm. Treatment of larger stones corresponded to a longer operative time, with procedural duration varying from 30 to 120 min. Of the reported causes of mortality in 42 patients, the aetiology was sepsis in over half of the patients, with other causes being cardiac-related, respiratory-related, multiorgan failure, and haemorrhagic complications.

CONCLUSIONS

Although the reported URS mortality rate seems to be low, there has been a rise in deaths over the past decade. Efforts must be made to have preoperative urine culture, and reduce operative time and stage procedures in patients with a large stone burden. Care must be taken in patients with robust preoperative assessment, intraoperative techniques, and postoperative monitoring for early detection of complications with interdisciplinary management of complex cases.

PATIENT SUMMARY

We reviewed the risk factors associated with postureteroscopy mortality and ways to minimise this. Evidence shows that although reported mortality remains low, there seems to be an increase in mortality in the past decade and urologists must remain vigilant of this.

Effectiveness of Flexible Ureterorenoscopy Versus Extracorporeal Shock Wave Lithotripsy for Renal Calculi of 5-15 mm: Results of a Randomized Controlled Trial

Background

Primary flexible ureterorenoscopy (URS) and extracorporeal shock wave lithotripsy (SWL) are treatment options in patients with renal calculi of 5-15 mm.

Objective

To compare effectiveness, complication rates, and pain scores between primary URS and SWL.

Design setting and participants

Between 2011 and 2016, patients with renal calculi between 5 and 15 mm were randomized to undergo either primary URS or SWL.

Outcome measurements and statistical analysis

Stone-free rate and size of residual fragments assessed by computed tomography after 3 mo, complications, and pain scores were evaluated.

Results and limitations

The study was prematurely closed after randomizing 44 patients due to poor accrual. The 3-mo stone-free rate and mean residual stone size were, respectively, 61% and 1.8 mm after URS and 48% and 2.4 mm after SWL. Early post-treatment pain scores were significantly higher after URS than after SWL on day 1 (3.3 vs 1.6, p =  0.02) and day 7 (5.2 vs 3.4, p =  0.04), but were no longer detectable after 3 wk and 3 mo, respectively. One Clavien-Dindo grade II complication was observed after URS (5%) and SWL (4%), while one (4%) grade IIIb complication was observed after SWL.

Conclusions

URS appears to be associated with higher early post-treatment discomfort, which could be associated with routine postoperative stenting. Owing to premature closure of this trial, the power was insufficient to formally compare URS and SWL; however, the present data might be informative to counsel patients about treatment outcomes and allow future meta-analyses.

Patient summary

This study was ended prematurely, but it contributes data about efficacy and side effects of different treatment options in patients with renal calculi.

The Comprehensive Complication Index (CCI) for improved reporting of complications in endourological stone treatment

The Clavien-Dindo Classification (CDC) lacks a combined score of multiple complications in one patient. The comprehensive complication index (CCI) circumvents this problem making it a valuable instrument to optimize quality control. We aimed to introduce and validate CCI in the treatment of urolithiasis. 60 day postoperative complications of 327 consecutive patients undergoing percutaneous nephrolitholapaxy (PNL) and ureterorenoscopy (URS) between 2017 and 2019 were retrospectively assessed and graded according to CDC. CCI was calculated for each patient. Overall morbidity scores of CCI and CDC were compared. Correlation analyses between the two scores and length of hospital stay (LOS) were performed. A multivariate analysis was performed to identify predictive factors for complications. Sample size calculation for an imaginary clinical trial was compared between CCI and CDC. A significant difference in overall morbidity between CCI and CDC was revealed for PNL (p < 0.001) and URS (p = 0.001). There was no statistically significant difference in comparing correlations between cumulative CCI and LOS versus non-cumulative CDC and LOS for both cohorts. Operating time > 90 min, maximum stone size, positive preoperative urine culture and PNL type (p < 0.001) were predictive factors for postoperative complications in PNL, while urine culture (p = 0.02) was for URS. Sample size calculation based on CCI resulted in a significant reduction of required patients for PNL (- 48%) and URS (- 84%) compared to CDC. CCI could successfully be validated in endourological stone treatment with the advantage of assessing complications in their entirety compared to CDC. CCI can significantly reduce the required sample size in future clinical trials.

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.

Infection-related hospitalization following ureteroscopic stone treatment: results from a surgical collaborative

Background

Unplanned hospitalization following ureteroscopy (URS) for urinary stone disease is associated with patient morbidity and increased healthcare costs. To this effect, AUA guidelines recommend at least a urinalysis in patients prior to URS. We examined risk factors for infection-related hospitalization following URS for urinary stones in a surgical collaborative.

Methods

Reducing Operative Complications from Kidney Stones (ROCKS) is a quality improvement (QI) initiative from the Michigan Urological Surgery Improvement Collaborative (MUSIC) consisting of academic and community practices in the State of Michigan. Trained abstractors prospectively record standardized data elements from the health record in a web-based registry including patient characteristics, surgical details and complications. Using the ROCKS registry, we identified all patients undergoing primary URS for urinary stones between June 2016 and October 2017, and determined the proportion hospitalized within 30 days with an infection-related complication. These patients underwent chart review to obtain clinical data related to the hospitalization. Multivariable logistic regression analysis was performed to determine risk factors for hospitalization.

Results

1817 URS procedures from 11 practices were analyzed. 43 (2.4%) patients were hospitalized with an infection-related complication, and the mortality rate was 0.2%. Median time to admission and length of stay was 4 and 3 days, respectively. Nine (20.9%) patients did not have a pre-procedure urinalysis or urine culture, which was not different in the non-hospitalized cohort (20.5%). In hospitalized patients, pathogens included gram-negative (61.5%), gram-positive (19.2%), yeast (15.4%), and mixed (3.8%) organisms. Significant factors associated with infection-related hospitalization included higher Charlson comorbidity index, history of recurrent UTI, stone size, intra-operative complication, and procedures where fragments were left in-situ.

Conclusions

One in 40 patients are hospitalized with an infection-related complication following URS. Awareness of risk factors may allow for individualized counselling and management to reduce these events. Approximately 20% of patients did not have a pre-operative urine analysis or culture, and these findings demonstrate the need for further study to improve urine testing and compliance

Association between ureteric stent dwell time and urinary tract infection

BACKGROUND

Ureteric stone obstruction commonly presents to the emergency department, with definitive management often involving ureteroscopy and laser lithotripsy. Insertion of a ureteric stent prior to staged lithotripsy is commonly performed in the public healthcare system. Foreign bodies in the urinary tract are also known to increase urinary tract infection (UTI) risk. This study aims to evaluate the association between stent dwell time and UTI prior to lithotripsy.

METHODS

The medical records of all patients who were treated for ureteric stones with initial stent insertion and staged lithotripsy, from 1 January 2018 to 30 June 2019 at a single tertiary centre, by eight urologists were retrospectively reviewed. Demographic features, disease factors and urine culture data were collected and analysed.

RESULTS

Of the 172 patients (median age 56.7 years) identified, one-third had a positive pre-stent urine culture. Twenty-three percent had a positive pre-lithotripsy urine culture with 38% of females compared with 15% of males having a positive culture (P = 0.001). Only 4.3% of patients had a pre-lithotripsy UTI when the stent dwell time was less than 1 month compared with 26.2% when ureteric stents were in situ for longer than 1 month (P = 0.021). The correlation between ureteric stent dwell time and pre-lithotripsy UTI was not linear. Patient comorbidities, stone size, burden and location were not statistically correlated to pre-lithotripsy UTI.

CONCLUSION

In delayed two-staged surgical management of acute urolithiasis, optimal ureteric stent dwell time is less than 1 month to reduce pre-lithotripsy UTI. Female gender is an independent risk factor for pre-lithotripsy UTI.

Flexible ureteroscopy and laser lithotripsy for renal stones 2 cm or greater: A single institutional experience

With improvements in endoscopy and laser technology, flexible ureteroscopy (FURS) has been a viable treatment option for large renal stones. Here, we share our experience of the FURS treatment for renal stones 2 cm or greater.We evaluated 251 consecutive patients who underwent FURS and holmium laser lithotripsy for renal stones 2 cm or greater between January 2015 and April 2019. Stone size was defined as the longest axis on non-contrast computed tomography. Data were retrospectively collected from electronic medical records. Patient demographics, stone clearance rates and perioperative complications were evaluated.There were 165 male patients and 86 female patients with an average age of 46.9 years (range 22-80 years). Mean stone size was 2.7 cm and the average number of procedures was 1.4 (range 1-5). The stone-free rate at the end of the first, second and third procedure was 61.9%, 82.9%, and 89.5%, respectively. The final stone-free rate decreased as stone size grows, and it was only 58.3% for kidney stones larger than 4 cm after an average of 2.3 procedures. The lowest clearance rates were observed in lower calyx calculi (87.2%) and multiple calyx calculi (83.5%). The overall complication rate was 15.1%, and the most common complication was postoperative fever (9.6%). One patient required blood transfusion, owing to postoperative coagulation disorders induced by urosepsis.Single or staged FURS is a practical treatment option for the renal stones sized 2 to 4 cm with acceptable efficacy and safety. Stone clearance rate of FURS treatment is mainly affected by stone size and location.

Albumin-globulin ratio: a novel predictor of sepsis after flexible ureteroscopy in patients with solitary proximal ureteral stones

Background

To identify predictors of sepsis after flexible ureteroscopy (fURS) in patients with unilateral, solitary, proximal ureteral stones and evaluate the association between albumin-globulin ratio (AGR) and sepsis.

Methods

Overall, 759 patients who underwent fURS were retrospectively enrolled. Univariate and multivariate logistic regression analyses were performed to identify predictors of sepsis after fURS in patients with solitary proximal ureteral stones. Then A nomogram was generated using the predictors.

Results

Sepsis occurred in 43 patients (5.7%), and 6 (0.8%) of them developed septic shock. Univariate analysis showed that age, female sex, albumin concentration, globulin concentration, AGR, pre-operative fever, white blood cell (WBC) count, urine culture (UC) result, urine WBC count, and urine nitrite result were predictors of sepsis. Multivariate analysis identified AGR <1.2 [odds ratio (OR) =2.810, 95% confidence interval (CI): 1.245-6.342, P=0.013] and positive UC (OR =10.520, 95% CI: 4.489-24.653, P<0.001) as independent predictors. When AGR <1.2 and positive UC were combined, area under the receiver operator characteristic curve was 0.825. Then patients were categorized by different AGR level ("≥1.4", "1.2-1.4", "1.0-1.2", "<1.0"), and corresponding sepsis rates were 27.7%, 9.8%, 4.5% and 2.5%.

Conclusions

Positive UC and low AGR were independent predictors of post-fURS sepsis. Cautious pre-operative evaluation and optimized treatment strategy should be considered to minimize infectious complications.

Pressurized-Bag Irrigation Versus Hand-Operated Irrigation Pumps During Ureteroscopic Laser Lithotripsy: Comparison of Infectious Complications

Introduction and Objectives: A variety of irrigation systems are available during ureteroscopy. We sought to compare gravity-driven pressure bags with hand-operated irrigation pumps in terms of postoperative complications after ureteroscopy with lithotripsy. Methods: A retrospective analysis of 234 patients undergoing flexible ureteropyeloscopy with laser lithotripsy by 24 supervised trainees over 4 years at a single teaching institution. Patients were divided into those who had procedures performed by using gravity-driven pressure bags fixed at 60 to 204 cm H₂O, vs those who had procedures performed by using a hand-operated irrigation pump capable of delivering 1 to 10 mL per flush. Variables including surgical duration, hypotension, fever, sepsis, and hematuria were extracted from the charts, along with the surgical techniques utilized. Statistical analyses included chi-squared tests and Student's t-tests. Results: There were no differences in gender, age, indication, or stone size in the two groups. Postoperative systemic inflammatory response syndrome was significantly greater in the hand-assisted n = 11/144 (7.6%) compared with the fixed irrigation group n = 1/90 (1.1%); p = 0.032. Emergency room presentations were greater in the hand irrigation group, n = 46/144 (32%) vs n = 12/90 (13%) in the pressure-bag irrigation, p = 0.002. Postoperative fever was also greater in the hand pump irrigation cohort compared with the continuous pressure cohort (13/144 [9%] vs 1/90 [1%], p = 0.011). No statistical difference was found between the two groups with respect to stone clearance and subsequent procedures required (p = 0.123). Conclusions: This analysis suggests that using continuous flow irrigation at a fixed maximum pressure of 150 mmHg (204 cm H₂O) or less may result in decreased pain, infection, and sepsis compared with handheld pressure irrigation.

[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.

Preoperative urine nitrite versus urine culture for predicting postoperative fever following flexible ureteroscopic lithotripsy: a propensity score matching analysis

PURPOSE

Multiple studies have reported that preoperative positive urine culture is an independent risk factor for postoperative fever (POF) after ureteroscopy (URS). Urine nitrite is associated urinary tract infections (UTIs). However, none of studies has explored the role of urine nitrite in the prediction of POF after flexible URS (fURS).

METHODS

Patients who underwent fURS by the same surgeon between 2009 and 2019 were screened. Sensitivity and specificity of urine culture and urine nitrite were calculated. Propensity score (PS) matching was performed to get a baseline-balanced retrospective cohort to avoid potential bias. Receiver operating characteristic-area under the curve (ROC-AUC) calculated was used to determine the predictive power of models. Decision curve analysis (DCA) was plotted to obtain the clinical benefit of the models.

RESULTS

Poseoperative fever (POF) is defined as the temperature of the patient higher than 38 ℃ within 72 h after operation, with no sign of infection in other systems. 31(2.8%) of 1095 cases had POF after fURL. Urine nitrite had a better specificity than urine culture for POF diagnosis (P < 0.001). After the PS matching, a well-balanced cohort of 24 POF group and 96 no-POF group was produced. The mean AUC from the bootstrap resampling method for urine nitrite model (AUC: 0.8736; 95% CI: 0.8731-0.8743) was significantly increased than that of the urine culture model (AUC: 0.8385; 95% CI: 0.8378-0.8392). The application of two kinds of POF predicting models could bring clinical net benefit when the probability is < 35%. However, urine nitrite model showed a better clinical net benefit acquirement compared to the urine culture model.

CONCLUSION

Preoperative positive urine nitrite may play a pivotal role in the prediction of POF after fURS and needs to be validated by future evidence.

Preoperative urine culture - Is it necessary to prevent infectious complications following ureterorenoscopy?

To prevent postoperative infectious complications, a urinary tract infection should be either diagnostically excluded or treated prior to ureterorenoscopy (URS). URS is a frequently performed endoscopic surgery for urological stone removal. Although the urinary dipstick test represents a simple and cost-effective method to gain information about the presence of urinary tract infection, the prevailing procedure is the more expensive and more time-consuming method of urine culture. The aim of this retrospective single-center study was to compare two strategies of perioperative prophylaxes prior to URS and to evaluate their impact on postoperative infectious complications: I) Obtaining a urine culture in every patient prior to URS or II) only in case of a positive dipstick test. Therefore, we retrospectively compared 201 patients in two cohorts undergoing URS. In one cohort a urine culture was obtained only in case of a positive dipstick test of midstream urine sample and in the second cohort a urine culture was prepared for every patient regardless of the dipstick's test results. The study's end point was determined as "infectious failure" (IF), if more than one of the following criteria are fulfilled: postoperative fever, elevation of inflammation laboratory values, significant prolongation of hospital stay and readmission within short-notice. Simple and multiple logistic regressions were performed to evaluate the influence of patient characteristics and preoperative urine analysis strategy on the occurrence of IF. Patients with a score of the American Society of Anesthesiologists (ASA) > 2 had a nearly statistically higher risk (p = .09) to develop an IF than healthier patients with an ASA score ≤ 2. Prestenting was determined as a significant predictive factor (p = .04) for a postoperative IF. No difference in patients with or without IF was detected regarding the two preoperative urine analysis strategies. Sensitivity of dipstick test was 87.5% and the negative predictive value was 89.66%. We found that a negative urine dipstick test result obtained prior to URS eliminated the need for urine culturing in predicting postoperative infectious complication. This approach can reduce preoperative preparation-time and costs without affecting postoperative complication outcomes.

Risk Factors for Systemic Inflammatory Response Syndrome Induced by Flexible Ureteroscope Combined with Holmium Laser Lithotripsy

Objective

To investigate the risk factors of systemic inflammatory response syndrome (SIRS) induced by flexible ureteroscope combined with Holmium laser lithotripsy. Patients and Methods. The clinical data from 216 consecutive patients who had undergone flexible ureteroscope combined with Holmium laser lithotripsy between August 2015 and May 2019 were retrospectively analyzed. To identify the risk factors of systemic inflammatory response syndrome induced by flexible ureteroscope combined with Holmium laser lithotripsy, the cases were divided into two groups according to whether they developed postoperative SIRS: SIRS group (21 cases) and non-SIRS group (195 cases). Age, gender, body mass index, stone size, surgery time, stone location, hydronephrosis, urine culture, hospital stay, stone-free rate, ureteral access sheath, and diabetes mellitus were collected. Univariate analysis was performed to calculate the potential factors. In order to determine the independence of the various factors, factors that potentially contributed to SIRS were compared between the SIRS group and the non-SIRS group. Furthermore, multivariate logistic regression analysis was used to identify the risk factors of systemic inflammatory response syndrome induced by flexible ureteroscopic lithotripsy.

Results

All patients were successfully treated with flexible ureteroscopic lithotripsy. The incidence of SIRS after flexible ureteroscopic lithotripsy was 9.7%. The univariate analysis demonstrated the potential risk factors of systemic inflammatory response syndrome induced by flexible ureteroscopic lithotripsy were stone size (p = 0.002), surgery time (p = 0.002), surgery time (p = 0.002), surgery time (p = 0.002), surgery time (p = 0.002), surgery time (p = 0.002), surgery time (p = 0.002), surgery time (p = 0.002), surgery time (.

Conclusions

Stone size, surgery time, urine culture, and ureteral access sheath are independent risk factors for SIRS induced by flexible ureteroscopic lithotripsy. Patients with these high-risk factors should be carefully evaluated to reduce systemic inflammatory response syndrome.

Predictors of Urinary Infections and Urosepsis After Ureteroscopy for Stone Disease: a Systematic Review from EAU Section of Urolithiasis (EULIS)

PURPOSE OF REVIEW

To present the latest evidence related to the predictors of urinary tract infections (UTIs) and urosepsis after ureteroscopy (URS) for stone disease.

RECENT FINDINGS

Our review suggests that almost half of all post-URS complications are related to infectious complications although reported rates of urosepsis were low. The use of antibiotic prophylaxis, treatment of pre-operative UTI, and low procedural time seem to reduce this risk. However, the risk is higher in patients with higher Charlson comorbidity index, elderly patients, female gender, long duration of pre-procedural indwelling ureteric stents and patients with a neurogenic bladder and with high BMI. Infectious complications following ureteroscopy can be a source of morbidity and potential mortality. Although majority of these are minor, efforts must be taken to minimise them especially in high-risk patients. This includes the use of prophylactic antibiotics, limiting stent dwell and procedural time, prompt identification and treatment of UTI and urosepsis, and careful planning in patients with large stone burden and multiple comorbidities.

The Role of Antegrade Irrigation via Percutaneous Nephrostomy on Surgical Outcomes in Semirigid Ureteroscopy among Patients with Upper Ureteral Stones

Objective

We aimed to investigate the role of antegrade irrigation via percutaneous nephrostomy on surgical outcomes in retrograde ureteroscopy in patients with upper ureter stones.

Materials and Methods

In this retrospective study, we analyzed 134 patients who underwent retrograde semirigid ureteroscopy for upper ureter stones between August 2012 and December 2017. Patients were divided into two groups: retrograde irrigation group (conventional URS) and antegrade irrigation group (using percutaneous nephrostomy). Operation time, postoperative hospital stay, complications, and stone-free rate were measured for each patient after ureteroscopy.

Results

The mean age in the retrograde irrigation and antegrade irrigation groups was 53.3 and 60.7 years, respectively (p=0.007). The operation time was 60.8 min vs. 43.0 min (p=0.002), and stone-free rate was 82.0 % vs. 95.5 % (p=0.033). Stone size, laterality, the proportion of male patients, and urinary tract infection prevalence were comparable between the groups. In the subgroup analysis of stone size >10 mm, the antegrade irrigation group had a shorter operation time and a higher stone-free rate. For stone size of 5-10 mm, operation time in the antegrade irrigation group was shorter and the stone-free rate between the two groups was comparable.

Conclusion

Antegrade irrigation via percutaneous nephrostomy during ureteroscopy has a higher stone-free rate with a shorter operation time without an increased urinary tract infection risk. Therefore, if percutaneous nephrostomy is necessary before ureteroscopy, antegrade irrigation of external fluid via percutaneous nephrostomy is strongly recommended.

The utility of preoperative and intraoperative cultures for guiding urosepsis empirical treatment

Objective:

Endoscopic upper urinary tract instrumentation is a common urological procedure; often associated with prior ureteric stenting and postoperative urosepsis. This study aimed to explore the clinical utility of preoperative urine and intraoperative urine and ureteric stent cultures in the management of urosepsis post upper urinary tract instrumentation.

Methods:

Prospective study involving pre-stented patients whose upper urinary tract was instrumented at a single centre between 2017 and 2018. Five cultures were collected per patient. Patients were tracked for development of postoperative urosepsis.

Results:

The study included 227 patients, with a 5.7% postoperative urosepsis rate. Risk of urosepsis was significantly associated with female gender, steroid use and having a colonized preoperative urine culture, intraoperative bladder urine or stent-end culture, or kidney urine culture. Patients with a colonized intraoperative bladder urine were 11 times more likely to develop urosepsis and were colonized with the same organism isolated from urosepsis cultures for 50% of cases.

Conclusions:

To our knowledge this is the largest cohort study which analyses five different urinary tract cultures and the relationship with postoperative urosepsis. A positive intraoperative bladder urine culture is an independent predictor of postoperative urosepsis development and causative organism, which could guide antibiotic management for these patients. Level of Evidence 3-b