Pre- and Postoperative Predictors of Infection-Related Complications in Patients Undergoing Percutaneous Nephrolithotomy

Risk factors and prediction model for postoperative complications in patients with struvite stones after percutaneous nephrolithotomy and flexible ureteroscopy

OBJECTIVE

To analyze the risk factors for complications in patients with struvite stones following percutaneous nephrolithotomy (PCNL) or flexible ureteroscopy (fURS), and to establish a nomogram for postoperative complications in patients following PCNL.

METHODS

A retrospective analysis was conducted on patients with struvite stones after PCNL and fURS at the Department of Urology, Peking University People's Hospital, from January 2012 to March 2022. The common pathogens and antimicrobial susceptibilities in preoperative midstream urine culture were analyzed. Logistic regression analyses were used to evaluate the risk factors. Receiver-operating characteristic (ROC) curve, calibration plots, and decision curve analysis (DCA) were used to assess the discrimination, accuracy, and practicability of the nomogram.

RESULTS

332 patients with struvite stones received one-stage PCNL or fURS, including 243 cases of PCNL and 89 cases of fURS. 72 patients (21.69%) developed postoperative complications. The most common pathogens in preoperative urine cultures were Escherichia coli, Proteus mirabilis, and Enterococcus faecalis. Multivariate logistic regression analysis showed that preoperative hemoglobin (OR = 0.981, P = 0.042), staghorn stone (OR = 4.226, P = 0.037), and positive preoperative midstream urine culture (OR = 2.000, P = 0.043) were independent risk factors for postoperative complications in patients following PCNL. The nomogram showed good performance in discrimination, accuracy, and applicability.

CONCLUSION

Preoperative hemoglobin, staghorn stone, and positive preoperative midstream urine culture were independent risk factors for postoperative complications in patients with struvite stones following PCNL. A nomogram was developed to predict the probability of postoperative complications.

Machine learning models to predict systemic inflammatory response syndrome after percutaneous nephrolithotomy

OBJECTIVE

The objective of this study was to develop and evaluate the performance of machine learning models for predicting the possibility of systemic inflammatory response syndrome (SIRS) following percutaneous nephrolithotomy (PCNL).

METHODS

We retrospectively reviewed the clinical data of 337 patients who received PCNL between May 2020 and June 2022. In our study, 80% of the data were used as the training set, and the remaining data were used as the testing set. Separate prediction models based on the six machine learning algorithms were created using the training set. The predictive performance of each machine learning model was determined by the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity and specificity using the testing set. We used coefficients to interpret the contribution of each variable to the predictive performance.

RESULTS

Among the six machine learning algorithms, the support vector machine (SVM) delivered the best performance with accuracy of 0.868, AUC of 0.942 (95% CI 0.890-0.994) in the testing set. Further analysis using the SVM model showed that prealbumin contributed the most to the prediction of the outcome, followed by preoperative urine culture, systemic immune-inflammation (SII), neutrophil to lymphocyte ratio (NLR), staghorn stones, fibrinogen, operation time, preoperative urine white blood cell (WBC), preoperative urea nitrogen, hydronephrosis, stone burden, sex and preoperative lymphocyte count.

CONCLUSION

Machine learning-based prediction models can accurately predict the possibility of SIRS after PCNL in advance by learning patient clinical data, and should be used to guide surgeons in clinical decision-making.

High-Risk Patients Undergoing Holmium Laser Enucleation of the Prostate Have Fewer Infections with a Longer Course of Preoperative Antibiotics

Introduction: There are minimal data to guide antibiotic management of patients undergoing holmium laser enucleation of the prostate (HoLEP) for benign prostatic hyperplasia. Specifically, management of high-risk patients who are catheter dependent or have positive preoperative urine cultures varies widely. We aimed to evaluate the effect of preoperative antibiotic duration on infectious complications in high-risk patients undergoing HoLEP. Methods: A multi-institutional retrospective review of patients undergoing HoLEP between 2018 and 2023 at five institutions was performed. Patients were defined as high risk if they were catheter-dependent (indwelling urethral catheter, self-catheterization, or suprapubic tube) or had a positive preoperative urine culture. These patients were categorized into long course (>3 days) or short course (≤3 days) of preoperative antibiotics. The primary outcome was 30-day infectious complications defined as a positive urine culture with symptoms. A t-test or Wilcoxon rank-sum test was used for continuous variables and Fisher's exact test was used for categorical variables. Logistic regression analysis was conducted to identify associations with infectious complications. Results: Our cohort included 407 patients, of which 146 (36%) and 261 (64%) were categorized as short course and long course of preoperative antibiotics, respectively. Median preoperative antibiotic duration was 1 day (interquartile range [IQR]: 0, 3 days) and 7 days (IQR: 5, 7 days) in the short and long cohorts, respectively. Thirty-day postoperative infectious complications occurred in 11 (7.6%) patients who received a short course of antibiotics and 5 (1.9%) patients who received a long course of antibiotics (odds ratio 0.24, 95% confidence interval 0.07-0.67; p = 0.009). Variables such as age, positive urine culture, and postoperative antibiotic duration were not significantly associated with postoperative infection after propensity score weighting. Conclusion: In high-risk patients undergoing HoLEP, infectious complications were significantly lower with a long course vs short course of antibiotics. Further prospective trials are needed to identify optimal preoperative antibiotic regimens.

Construction of an alignment diagram model for predicting calculous obstructive pyonephrosis before PNL

Background

To develop a model for the accurate prediction of calculous obstructive pyonephrosis prior to percutaneous nephrolithotomy (PNL), leading to early local anaesthesia microchannel nephrostomy for drainage of pyonephrosis.

Methods

By comparing the differences in baseline clinical indicators between the pyonephrosis group and nonpyonephrosis groups, independent risk factors were screened out, and a diagnostic alignment diagram model for predicting calculus obstructive pyonephrosis before PNL was established.

Results

Multivariate regression analysis showed that preoperative blood neutrophil count (Neu), serum creatinine level (Scr), serum albumin level (Alb), urine nitrite (UN), hydronephrosis density (HD) and fever history within one month (HFWOM) were independent risk factors for calculous obstructive pyonephrosis. The AUC value of the receiver operating characteristic (ROC) curve was 0.929. The calibration curves showed that the predictive model was well corrected and that the predictive model had strong consistency. Decision analysis curves showed good clinical efficacy of the model.

Conclusion

The alignment diagram model accurately predicts patients with preoperative calculous obstructive pyonephrosis in the PNL and provides an evidence-based basis for early renal microchannel nephrostomy.

A novel post-percutaneous nephrolithotomy sepsis prediction model using machine learning

OBJECTIVES

To establish a predictive model for sepsis after percutaneous nephrolithotomy (PCNL) using machine learning to identify high-risk patients and enable early diagnosis and intervention by urologists.

METHODS

A retrospective study including 694 patients who underwent PCNL was performed. A predictive model for sepsis using machine learning was constructed based on 22 preoperative and intraoperative parameters.

RESULTS

Sepsis occurred in 45 of 694 patients, including 16 males (35.6%) and 29 females (64.4%). Data were randomly segregated into an 80% training set and a 20% validation set via 100-fold Monte Carlo cross-validation. The variables included in this study were highly independent. The model achieved good predictive power for postoperative sepsis (AUC = 0.89, 87.8% sensitivity, 86.9% specificity, and 87.4% accuracy). The top 10 variables that contributed to the model prediction were preoperative midstream urine bacterial culture, sex, days of preoperative antibiotic use, urinary nitrite, preoperative blood white blood cell (WBC), renal pyogenesis, staghorn stones, history of ipsilateral urologic surgery, cumulative stone diameters, and renal anatomic malformation.

CONCLUSION

Our predictive model is suitable for sepsis estimation after PCNL and could effectively reduce the incidence of sepsis through early intervention.

Comparative Effectiveness Randomized Clinical Trial Using Next-generation Microbial Sequencing to Direct Prophylactic Antibiotic Choice Before Urologic Stone Lithotripsy Using an Interprofessional Model

Background

Next-generation sequencing (NGS) methods for microbial profiling have increased sensitivity to detect urinary pathogens.

Objective

To determine whether NGS microbial profiling can be used to guide antibiotic prophylaxis and reduce infection compared with the standard of care.

Design setting and participants

A prospective randomized controlled clinical trial of patients undergoing urologic stone interventions at an academic health center from December 2019 to January 2022 was conducted. Urine was collected at the preoperative visit for standard culture and intervention NGS diagnostics. Evaluable patients were culture negative, met 2-wk follow-up, and did not cancel surgery. Of 240 individuals (control = 121, intervention = 119), 83 control and 74 intervention patients were evaluable.

Intervention

Microbial findings (paired quantitative polymerase chain reaction and NGS) were sent to an infectious disease pharmacist to recommend prophylactic antimicrobial regimen.

Outcome measurements and statistical analysis

The primary outcome was postoperative urinary infection within the follow-up period (Fisher's exact test). The primary outcome was analyzed by modified intent-to-treat (mITT) and per-protocol analyses. Secondary endpoints considered included positive culture concordance, antibiotic use, and adverse events. Additional post hoc analyses investigated factors contributing to infection (univariate logistic regression).

Results and limitations

The intervention significantly reduced postsurgical urinary infection risk by 7.1% (-0.73%, 15%) compared with the standard of care in the mITT analysis (1.4% vs 8.4%, p = 0.045) or by 8.5% (0.88%, 16%) compared with the per-protocol analysis (0% vs 8.5%, p = 0.032). NGS-guided treatment altered the distribution of antibiotics used (p = 0.025), and antibiotics poorly matched with NGS findings were associated with increased infection odds (odds ratio [OR] = 5.9, p = 0.046). Women were at greater odds to develop infection (OR = 10, p = 0.03) and possessed differentiated microbial profiles (p < 0.001).

Conclusions

Urinary microbial NGS-guided antibiotic prophylaxis before endoscopic urologic stone lithotripsy improves antibiotic selection to reduce healthcare-associated urinary infections; however, treatment efficacy may be limited by the ability to adhere to the recommended protocol.

Patient summary

We investigated whether microbial DNA sequencing could improve the selection of antibiotics before kidney stone surgery in patients not known to have any bacteria in the urine on standard culture. We found that using microbe DNA to guide antibiotic choices decreased postoperative infection rate and may encourage individualized use of available antibiotics.

Percutaneous nephrolithotomy in patients with incidental encountered purulent urine at initial puncture

We are reporting the 39 patients' outcomes who underwent percutaneous nephrolithotomy and purulent urine encountered at the initial steps of surgery. Of 873 patients who underwent PCNL, 48 had purulent fluid during the initial puncture. After excluding those at risk for infection, we studied 39 patients' preoperative and postoperative variables-including postoperative day (POD) 1, 3, 5 fevers. In group 1, 21 patients had a nephrostomy tube placed, and PCNL was postponed. In group 2, 18 patients had successful stone removal in the first session. All surgeries were successful, with no septic events during follow-up. No significant differences in preoperative variables were found. 14% and 22% of patients in groups 1 and 2 had infected fluid (p = 0.470). Four patients in group 1 (19%) and seven patients in group 2 (38.9%) had a high fever (≥ 38 C) on POD1 (p = 0.171), and 1 (5%) in group 1 and 3 (17%) in group 2 had high fever on POD 3 (p = 0.22). No patients remained with high fever on POD5. Mild sepsis was diagnosed in 9.5% of group 1 and 16% of group 2 (p = 0.820), and hospitalization time differed significantly (p < 0.001). Stone size and operation time were correlated with postoperative fever, and prolonged hospital stays were associated with positive blood cultures and postponed procedures. PCNL with proper technique and antibiotics can lead to quicker recovery and reduced hospitalization time in selected patients with pus in their pelvicalyceal system.

Regulatory effect of Pseudomonas aeruginosa mannose-sensitive hemagglutinin on inflammation and immune function in percutaneous nephrolithotomy patients with upper urinary tract calculi complicated with infection

Objective

To study the effect of an injection of Pseudomonas aeruginosa mannose-sensitive hemagglutinin (PA-MSHA) on inflammation and immune function in patients with upper urinary tract calculi complicated by infection who have undergone percutaneous nephrolithotomy.

Methods

We retrospectively recorded the clinical data of patients with upper urinary tract calculi complicated by infection who have undergone Percutaneous nephrolithotomy(PCNL) in the Department of Urology, 2nd Affiliation Hospital of Kunming Medical University, from March to December 2021. Clinical data include general condition, laboratory index, CT, postoperative body temperature, heart rate, respiration, SIRS, sepsis, etc. Patients were divided into treated and control groups according to whether they had received a preoperative PA-MSHA injection. The two groups were compared for indices of inflammation and complications of infection after PCNL. Pre- and post-operative lymphocyte subsets and immunoglobulin changes were compared.

Results

115 patients were included in the study, including 43 in the treatment group and 72 in the control group. After Propensity Score Matching, 90 patients were divided into treatment (n=35) and control (n=55) groups. The postoperative inflammation index was higher in the treatment group than in the control group (P<0.05). The incidence of postoperative SIRS was higher in the treatment group than control (P<0.05). There were no cases of sepsis in either group. The double-positive T cells lymphocyte subsets were higher in the treatment group than in the control group ((P<0.05). Pre- and post-operative changes in immune function: total T lymphocyte count reduced, NK and NKT cell count increased in the control group, double-positive T cell count increased in the treatment group, IgG, IgA, IgM, complement C3 and C4 count reduced in both groups post-operatively.

Conclusion

This study found that patients with upper urinary tract calculi and infection treated with antibiotic-based PA-MSHA before percutaneous nephrolithotomy had an increased inflammatory response after surgery, which may play a role in the prevention and treatment of sepsis. The percentage of double-positive T cells in the peripheral blood was increased after PA-MSHA treatment, which may have an immunomodulatory and protective effect in PCNL patients with stones complicated by infection.

A retrospective study using machine learning to develop predictive model to identify urinary infection stones in vivo

Preoperative diagnosis of urinary infection stones is difficult, and accurate detection of stone composition can only be performed ex vivo. To provide guidance for better perioperative management and postoperative prevention of infection stones, we developed a machine learning model for preoperative identification of infection stones in vivo. The clinical data of patients with urolithiasis who underwent surgery in our hospital from January 2011 to December 2015 and January 2017 to December 2021 were retrospectively analyzed. A total of 2565 patients were included in the study, and 1168 eligible patients with urinary calculi were randomly divided into training set (70%) and test set (30%). Five machine learning algorithms (Support Vector Machine (SVM), Multilayer Perceptron (MLP), Decision Tree (DT), Random Forest Classifier (RFC), and Adaptive Boost (AdaBoost)) and 14 preoperative variables were used to construct the prediction model. The performance measure was the area under the receiver operating characteristic curve (AUC) of the validation set. The importance of 14 features in each prediction model for predicting infection stones was analyzed. A total of 89 patients (5.34%) with infection stones were included in the validation set. All the five prediction models showed strong discrimination in the validation set (AUC: 0.689-0.772). AdaBoost model was selected as the final model (AUC: 0.772(95% confidence interval, 0.657-0.887); Sensitivity: 0.522; Specificity: 0.902), UC positivity, and urine pH value were two important predictors of infection stones. We developed a predictive model through machine learning that can quickly identify infection stones in vivo with good predictive performance. It can be used for risk assessment and decision support of infection stones, optimize the disease management of urinary calculi and improve the prognosis of patients.

A nomogram for predicting postoperative urosepsis following retrograde intrarenal surgery in upper urinary calculi patients with negative preoperative urine culture

Retrograde intrarenal surgery (RIRS) is one of the main surgical methods for upper urinary calculi, but severe complications of infection may occur after surgery. This study aimed to establish and validate a preoperative nomogram for predicting postoperative urosepsis following retrograde intrarenal surgery to treat upper urinary calculus in patients with a negative preoperative urine culture. We retrospectively recruited 1767 patients with negative preoperative urine cultures who underwent retrograde intrarenal surgery to treat upper urinary calculi from January 2017 to April 2022. The independent risk factors for urosepsis include a solitary kidney, positive urine nitrite, operative time ≥ 75 min, history of recurrent urinary tract infections, and history of diabetes were identified by univariate analysis and multivariate binary logistic regression analysis, which construct a nomogram. The receiver operating characteristic curve of the nomogram for predicting urosepsis was 0.887 in the training cohort and 0.864 in the validation cohort, respectively. The calibration curve and decision curve analysis demonstrated great consistency and clinical utility of the nomogram. Therefore, the nomogram combining preoperative independent risk factors can predict the probability of a postoperative urosepsis following retrograde intrarenal surgery in patients with a negative preoperative urine culture, which could help urologists take preventive measures in advance after surgery to avoid more serious complications of infection.

The influencing factors of infectious complications after percutaneous nephrolithotomy: a systematic review and meta-analysis

Infection is the most common complications of percutaneous nephrolithotomy (PCNL) in treating urinary calculi. However, the risk factors for developing infectious complications after surgery have not been clarified, and the predictive value of some factors is controversial. This study aimed to assess the risk factors for postoperative infectious complications of PCNL. We performed a systematic search of PubMed, Web of Science, Cochrane Library, and EMBASE to obtain studies reporting risk factors for postoperative infection complications after PCNL. In this review, demographic factors, laboratory test factors, and perioperative factors were evaluated. The odds ratio (OR) or mean difference (MD) with a 95% confidence interval (CI) was calculated to assess the risk factors. A total of 18 studies were included, with a total of 7161 study patients with a mean age of 46.4 to 55.5 years and an incidence of infectious complications after PCNL ranging from 2.4% to 40.4%. Twelve factors were identified as independent risk factors for post-PCNL infection complications (P < 0.05), female (OR = 1.60, 95% CI 1.23-2.07), positive urine culture (UC) (OR = 3.16, 95% CI 2.11-4.74), positive renal pelvis urine culture (RPUC) (OR = 5.81, 95% CI 1.75-19.32), positive stone culture (SC) (OR = 5.11, 95% CI 1.46-17.89), positive urine leukocyte (OR = 3.61, 95% CI 2.45-5.34), infected stones (OR = 7.00, 95% CI 1.27-38.55), elevated blood leukocyte (MD = 0.71, 95% CI 0.31-1.10), elevated neutrophil-to-lymphocyte ratio (NLR) (MD = 0.55, 95% CI 0.43-0.66), preoperative stenting (OR = 1.55, 95% CI 1.10-2.20), multiple puncture access (OR = 2.58, 95% CI 1.75-3.82), prolonged operative time (MD = 10 20, 95% CI 4.80-15.60), and postoperative residual stone (OR = 1.56, 95% CI 1.24-1.98). Female, UC positivity, RPUC positivity, SC positivity, urine leukocyte positivity, infected stones, elevated peripheral blood leukocytes, elevated NLR, preoperative stent implantation, multiple puncture channels, prolonged operation time, and postoperative residual stones were identified as independent risk factors for infection complications after PCNL.

International Alliance of Urolithiasis (IAU) Guideline on percutaneous nephrolithotomy

The International Alliance of Urolithiasis (IAU) would like to release the latest guideline on percutaneous nephrolithotomy (PCNL) and to provide a clinical framework for surgeons performing PCNLs. These recommendations were collected and appraised from a systematic review and assessment of the literature covering all aspects of PCNLs from the PubMed database between January 1, 1976, and July 31, 2021. Each generated recommendation was graded using a modified GRADE methodology. The quality of the evidence was graded using a classification system modified from the Oxford Center for Evidence-Based Medicine Levels of Evidence. Forty-seven recommendations were summarized and graded, which covered the following issues, indications and contraindications, stone complexity evaluation, preoperative imaging, antibiotic strategy, management of antithrombotic therapy, anesthesia, position, puncture, tracts, dilation, lithotripsy, intraoperative evaluation of residual stones, exit strategy, postoperative imaging and stone-free status evaluation, complications. The present guideline on PCNL was the first in the IAU series of urolithiasis management guidelines. The recommendations, tips and tricks across the PCNL procedures would provide adequate guidance for urologists performing PCNLs to ensure safety and efficiency in PCNLs.

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.

Nomogram for predicting risk factor of urosepsis in patients with diabetes after percutaneous nephrolithotomy

Background

Urosepsis is an infectious complication after percutaneous nephrolithotomy (PCNL). This study aimed to analyze the perioperative factors related to urosepsis after PCNL for upper urinary calculi and establish a nomogram to predict the probability of postoperative urosepsis based on the risk factors.

Methods

The Clinical data of one-stage PCNL for upper urinary stones in patients already diagnosed with type 2 diabetes between June 2010 and June 2020 were retrospectively analyzed. The patients were divided into two groups according to whether urosepsis occurred after surgery, and univariate and multivariate logistic regression analyses evaluated the risk factors for urosepsis. Moreover, the corresponding nomogram prediction model was determined by the regression coefficient.

Results

All 366 patients with diabetes underwent one-stage PCNL. Seventy-one (19.4%) patients had urosepsis after surgery, and their hospitalization time was longer than that of patients without urosepsis. Moreover, the incidence of non-infection-related complications was higher. Multivariate logistic regression analysis revealed four independent risk factors associated with postoperative urosepsis, including positive urine nitrite (odds ratio [OR] = 3.326, P = 0.007), positive urine culture (OR = 2.213, P = 0.023), intraoperative hypotension (OR = 8.968, P < 0.001), and staghorn calculi (OR = 3.180, P = 0.002). The above independent risk factors were used as variables to construct the nomogram. The nomogram model was internally validated. The calculated concordance index was 0.824. The Hosmer–Lemeshow goodness-of-fit test was performed (P = 0.972 > 0.05). The area under the curve of this model was 0.831, indicating that the nomogram model had good accuracy in predicting the probability of urosepsis in patients who underwent PCNL with diabetes and had good consistency with the actual risk.

Conclusion

Positive urine culture, positive urine nitrite, staghorn calculi, and intraoperative hypotension were independent risk factors for urosepsis in patients who underwent one-stage PCNL with diabetes. The new nomogram could accurately assess the risk of urosepsis after PCNL in patients with diabetes.

Infectious complications of endourological treatment of kidney stones: A meta-analysis of randomized clinical trials

OBJECTIVE

Endourological treatment is associated with a risk of postoperative febrile urinary tract infections and sepsis. The aim of this study was to review the reported rate of infectious complications in relation to the type and modality of the endourologic procedure.

METHODS

This systematic review was conducted in accordance with the PRISMA guidelines. Two electronic databases (PubMed and EMBASE) were searched. Out of 243 articles retrieved we included 49 studies after full-text evaluation.

RESULTS

Random-effects meta-analysis demonstrated that retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PCNL) were associated with not significantly different odds of getting fever (OR = 1.54, 95% CI: 0.99 to 2.39; p = 0.06) or sepsis (OR = 1.52, 95% CI: 0.37 to 6.20, p = 0.56). The odds of getting fever were not significantly different for mini PCNL compared to standard PCNL (OR = 1.11, 95% CI: 0.85 to 1.44; p = 0.45) and for tubeless PCNL compared to standard PCNL (OR = 1.34 95% CI: 0.61 to 2.91, p = 0.47). However, the odds for fever after PCNL with suctioning sheath were lower than the corresponding odds for standard PCNL (OR = 0.37, 95% CI: 0.20 to 0.70, p = 0.002). The odds of getting fever after PCNL with perioperative prophylaxis were not different from the corresponding odds after PCNL with perioperative prophylaxis plus a short oral antibiotic course (before or after the procedure) (OR = 1.31, 95% CI: 0.71 to 2.39, p = 0.38).

CONCLUSIONS

The type of endourological procedure does not appear to be decisive in the onset of infectious complications, although the prevention of high intrarenal pressure during the procedure could be crucial in defining the risk of infectious complications.   on behalf of U-merge Ltd. (Urology for emerging countries), London-Athens-Dubai.

Nomograms for Predicting the Risk of SIRS and Urosepsis after Uroscopic Minimally Invasive Lithotripsy

Objective. To analyze the potential risk factors that affect the development of urosepsis following uroscopic minimally invasive lithotripsy and to develop a nomogram that predicts the probability of postoperative urosepsis. Methods. We retrospectively analyzed the clinical data from patients that underwent percutaneous nephrolithotripsy (PCNL) or ureteroscopic lithotripsy (URL) between January 2018 and December 2019. The enrolled patients were grouped twice according to systemic inflammatory response syndrome (SIRS) and quick sequential organ failure assessment (qSOFA). After univariate and multivariate logistic regression analyses, we identified the independent predictive factors affecting the development of postoperative SIRS and urosepsis, and built the nomograms. Results. From January 2018 to December 2019, 1959 patients underwent PCNL or URL, of whom 236 patients were accorded with the inclusion criteria. Of all 236 patients, 64 (27.12%) patients developed postoperative SIRS, and 17 (7.20%) patients developed postoperative urosepsis. Multivariate logistic regression analysis showed that positive preoperative urine culture (PUC+) ( $\text{OR}=2.331$ , $P=0.044$ ), procalcitonin (PCT) ( $\text{OR}=1.093$ , $P=0.037$ ), C-reactive protein (CRP) ( $\text{OR}=1.017$ , $P<0.001$ ), and neutrophil ratio (NEUT%) ( $\text{OR}=1.091$ , $P=0.004$ ) of postoperative were independent predictors of SIRS, and PCT ( $\text{OR}=1.017$ , $P=0.003$ ) and CRP ( $\text{OR}=1.080$ , $P<0.001$ ) were independent predictors of urosepsis. Additionally, the nomograms demonstrated good accuracy in predicting SIRS and urosepsis with a C-index of 0.884 (95% CI: 0.835-0.934) and 0.941 (95% CI: 0.885-0.996), respectively. Conclusions. The nomograms achieved the prediction of SIRS and urosepsis after uroscopic minimally invasive lithotripsy. Using this model, the risk of SIRS or urosepsis for an individual patient can be determined, which facilitates early diagnosis and rational treatment.

Efficacy of Super-Mini-PCNL and Ureteroscopy in Kidney Stone Sufferers and Risk Factors of Postoperative Infection

To investigate the efficacy of super-mini-PCNL (SMP) and ureteroscopy in kidney stone (KS) sufferers and learn the risk factors of postoperative infection. A retrospective analysis was performed on 180 KS sufferers who were diagnosed and treated in our hospital from May 2019 to May 2021. They were enrolled into an observation group (OG, n = 104) and a control group (CG, n = 76) based on different treatment methods. Therein, the former was treated with SMP, while the latter was treated with ureteroscopy. The operation time, blood loss, hospital stay, recent stone-free rate (one week after operation), changes of serum creatinine (SCr), blood urea nitrogen (BUN), and cystatin C (CysC) levels before and after operation and complications were compared. Those sufferers were assigned to infected and uninfected groups based on their postoperative infection. The risk factors were assessed through logistic regression, and the model formula was established. The predictive value of this model for infection was tested through RO. Compared with CG, the operation time of the OG was longer, the blood loss and hospital stay were lower (P < 0.05), and the stone-free rate was higher (P < 0.05). Renal function indexes before and after treatment (P > 0.05) and postoperative complications revealed no significant difference (P > 0.05). Logistic regression analysis manifested that preoperative urinary tract infection (OR: 4.690, 95% CI: 1.170-18.802), preoperative blood glucose level (OR: 11.188, 95% CI: 2.106-59.442), positive urine culture (OR: 10.931, 95% CI: 2.453-48.705), and infectious stones (OR: 3.951, 95% CI: 1.020-15.300) were independently related to infection. The risk prediction equation is logit(p)=-8.913+1.545 × X1+2.415 × X2+2.392 × X3+1.374 × X4, with a goodness-of-fit value of 0.545. The AUC is 0.930, so SMP is superior to ureteroscopy in KS sufferers. Preoperative urinary tract infection, preoperative blood glucose level, positive urine culture, and infectious stones are independently related to infection.

Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and lymphocyte-monocyte ratio (LMR) in predicting systemic inflammatory response syndrome (SIRS) and sepsis after percutaneous nephrolithotomy (PNL)

The objective of this prospective observational study was to assess the clinical significance of neutrophil–lymphocyte ratio (NLR), platelet–lymphocyte ratio (PLR) and lymphocyte–monocyte ratio (LMR) as potential biomarkers to identify post-PNL SIRS or sepsis. Demographic data and laboratory data including hemoglobin (Hb), total leucocyte count (TLC), serum creatinine, urine microscopy and culture were collected. The NLR, LMR and PLR were calculated by the mathematical division of their absolute values derived from routine complete blood counts from peripheral blood samples. Stone factors were assessed by non-contrast computerized tomography of kidneys, ureter and bladder (NCCT KUB) and included stone burden (Volume = L × W × D × π × 0.167), location and Hounsfield value and laterality. Intraoperative factors assessed were puncture site, tract size, tract number, operative time, the need for blood transfusion and stone clearance. Of 517 patients evaluated, 56 (10.8%) developed SIRS and 8 (1.5%) developed sepsis. Patients developing SIRS had significantly higher TLC (10.4 ± 3.5 vs 8.6 ± 2.6, OR 1.19, 95% CI 1.09–1.3, p = 0.000002), higher NLR (3.6 ± 2.4 vs 2.5 ± 1.04, OR 1.3, 95% CI = 1.09–1.5, p = 0.0000001), higher PLR (129.3 ± 53.8 vs 115.4 ± 68.9, OR 1.005, 95% CI 1.001–1.008, p = 0.005) and lower LMR (2.5 ± 1.7 vs 3.2 ± 1.8, OR 1.18, 95% CI 1.04–1.34, p = 0.006). Staghorn stones (12.8 vs 3.24%, OR 4.361, 95% CI 1.605–11.846, p = 0.008) and long operative times (59.6 ± 14.01 vs 55.2 ± 16.02, OR 1.01, 95% CI 1.00–1.03, p = 0.05) had significant association with postoperative SIRS. In conclusion, NLR, PLR and LMR can be useful independent, easily accessible and cost-effective predictors for early identification of post-PNL SIRS/sepsis.

Neglected analytes in the 24-h urine: ammonium and sulfate

PURPOSE OF REVIEW

Evaluation of the kidney stone patient includes measurement of 24 h urine chemistries. This review summarizes the application of physiologic principles to the interpretation of urine chemistries, using sulfate and ammonium to estimate diet acid load, and the renal response.

RECENT FINDINGS

There has been increased recognition of the need to measure urine ammonium excretion in the clinical setting in order to understand renal acid excretion. Some 24 h urine kidney stone panels include ammonium measurements, providing an opportunity to apply this measurement to clinical practice. In order to better interpret ammonium excretion, one needs an estimate of dietary acid load to understand the driving forces for ammonium excretion. Sulfate is also included in some kidney stone panels and functions as an estimate of diet acid load. Combining these analytes with urine pH, the clinician can quickly estimate dietary stone risk as well as potential bowel disease, acidification disorders, and the presence of urease producing bacteria; all of which can affect stone risk.

SUMMARY

Measurement of ammonium and sulfate excretion along with urine pH provide important insights into the acid/alkali content of diet, presence and severity of bowel disease, presence of renal acidification disorders, and urinary infection.

Postoperative infective complications following percutaneous nephrolithotomy

Introduction

Percutaneous nephrolithotomy (PCNL) is recommended as the first choice of therapeutic strategy for patients with renal stones larger than 2 cm. It is reported that up to one-third of patients might have some perioperative complications, especially fever and urinary tract infections, which constitutes about 21%-39.8% of all the complications.

Primary and Secondary

The primary aim of the study was to study about the proportion of patients getting post-operative infective complications following PCNL. The secondary aim was to study the patient, stone and procedure related risk factors associated with the infective complications.

Settings and Design

This is an institution-based observational study.

Materials and Methods

All patients who underwent PCNL in the Department of Urology, Medical College, Thiruvananthapuram, during 3 years from September 2016- to August 2019, were included in the study. In this study, the demographic factors and factors related to the patient, stone, and the procedure were collected and analyzed.

Statistical Analysis Used

Data analysis was performed using SPSS version 22.0.

Results

During the 3-year period, a total of 201 patients with renal stones were treated with PCNL in our hospital. Of this 190 cases were taken for analysis. The mean age of patients was 47.7 years, 148 (77.9%) were male, 42 (22.1%) were female, The final outcomes evaluated were episodes of fever, documented urinary tract infection (UTI), pyelonephritis, and sepsis. Thirty-six (18.9%) patients had fever, of which 21 (11.1%) had UTI, 6 (3.1%) had pyelonephritis and 5 (2.6%) developed sepsis.

Conclusions

Post-PCNL complications are more commonly found in patients with history of preoperative UTI, previous history of renal surgeries, large stone burden, operative procedure more than 90 min, and presence of residual calculi.

The value of procalcitonin for predicting urosepsis after mini-percutaneous nephrolithotomy or flexible ureteroscopy based on different organisms

PURPOSE

To assess the value of procalcitonin (PCT) as an early biomarker for predicting urosepsis caused by Gram-negative (GN) bacteria, Gram-positive (GP) bacteria and fungi following mini-percutaneous nephrolithotomy (mPCNL) and flexible ureteroscopy (FURS).

METHODS

A total number of 356 patients with positive preoperative UC (urine cultures) who underwent mPCNL and FURS between June 2017 and January 2021 were retrospectively analyzed. Univariable analysis and multivariable logistic regression analysis were conducted to compare the predictors for urosepsis caused by different organisms. Furthermore, the nomogram was established as a predicted model for urosepsis.

RESULTS

Among 356 positive UC, 265 (74.4%) were positive for GN bacteria, 77 (21.4%) for GP bacteria and 14 (3.9%) for fungal pathogens. Escherichia coli (48.9%) were the predominant pathogens and Enterococcus (54/77) were the most common GP bacteria. Multivariate logistic regression analysis showed that positive nitrite (OR 3.31, 95% CI 1.20-9.14; P = 0.021), operative time > 90 min (OR 3.10, 95% CI 1.10-8.75, P = 0.033) and postoperative PCT > 0.1 ng/mL (OR 56.18, 95% CI 15.20-207.64, P < 0.001) were associated with postoperative urosepsis originated in GN infections, while urosepsis caused by GP bacteria and fungi was not associated with PCT > 0.1 ng/mL (P = 0.198), only stone burden > 800 mm² (OR 3.69, 95% CI 1.01-13.53, P = 0.049) was an independent risk factor.

CONCLUSIONS

For patients with positive preoperative UC, postoperative PCT > 0.1 ng/mL was an independent risk factor of post-PCNL and post-FURS urosepsis caused by GN bacteria rather than GP bacteria and fungi.

Analysis of pre-operative risk factors for post-operative urosepsis following mini-percutaneous nephrolithotomy in patients with large kidney stones

PURPOSE

To assess the pre-operative risk factors for post-operative urosepsis following mini-percutaneous nephrolithotomy (mPCNL) in patients with large kidney stones. Methods：Records of 171 patients with large (≥30mm) kidney stones who underwent mPCNL from December 2013 to October 2019 were reviewed. Demographic data of patients, pre-operative urine analysis, urine culture, routine blood tests and abdominal computerized cosmography data were collected and analyzed. A predictive nomogram model was established based on the results of logistic regression.

RESULTS

29 patients (17%) developed post-operative urosepsis in this study. Univariate analysis demonstrated that preoperative urine leukocytes (P <0.001), urine nitrite (P <0.001), stones in adjacent calices on the coronal plane (P <0.001), the maximum cross-sectional area of stones (P <0.001), the diameter of hydronephrosis (P =0.010) and number of stones (P=0.044) were associated with post-operative urosepsis after mPCNL in patients with large kidney stones. And pre-operative urine leukocytes ≥450/ µl (P=0.002) was the only independent risk factor for post-operative urosepsis in multivariate logistic regression analysis. Based on the results of multivariate regression, a nomogram model was established for the prediction of post-operative urosepsis with ideal discrimination (area under receiver operating characteristic curve was 0.867).

CONCLUSION

Patients with certain pre-operative characteristics, including higher urine leukocytes, positive urine nitrite, stones in adjacent calices on the coronal plane, larger maximum cross-sectional area of stones, larger diameter of hydronephrosis and larger number of stones, who received mPCNL may have a higher risk of postoperative urosepsis. A predictive model can help urologists identify patients who may develop post-operative urosepsis with high probability.

The characteristics and influencing factors of fever in postoperative patients undergoing percutaneous nephrolithotomy: A retrospective analysis

Percutaneous nephrolithotomy (PCNL) is commonly used for the treatment of upper urinary calculi in clinical setting, and fever is a common complication after PCNL. It is necessary to evaluate the risk factors of fever in patients undergoing PCNL, to provide insights into the management of PCNL.Patients who underwent PCNL in our hospital from January 2018 to August 2020 were included. The clinical data of postoperative fever and no fever patients were collected and assessed. Logistic regression analyses were conducted to analyze the risk factors for fever in patients undergoing PCNL.A total of 276 patients undergoing PCNL were included, the incidence of postoperative fever for patients undergoing PCNL was 19.39%. No significant differences in the gender, body mass index, alcohol drinking, smoking, hypertension, hyperlipidemia, intraoperative blood infusion, length of hospital stay between fever patients, and no fever patients were found (all P > .05). There were significant differences in the age, diabetes, size of stones, duration of surgery between fever patients, and no fever patients (all P < .05). Age ≥60 years (odds ratio [OR] 2.143, 95% confidence interval [CI] 1.101∼3.264), diabetes (OR 2.218, 95% CI 1.176∼4.642), size of stone ≥2 cm (OR 1.428, 95%CI 1.104∼2.055), duration of surgery ≥100 minutes (OR 1.334, 95% CI 1.015∼1.923) were the risk factors for fever in patients with PCNL (all P < .05). Escherichia coli (48.44%), Staphylococcus aureus (18.75%), and Candida albicans (10.93%) were the top 3 pathogenic bacteria of urine culture.Fever is one of the common complications after PCNL. Patients with high-risk factors should be given full attentions and take corresponding preventive measures targeted on risks.

Risk factors for urinary infection after retrograde upper urinary lithotripsy: Implication for nursing

ABSTRACT

There are needs to evaluate the risk factors for urinary infection after retrograde upper urinary lithotripsy, to provide insights into the management and nursing care of patients with retrograde upper urinary lithotripsy.Patients who received retrograde upper urinary lithotripsy with a Foley 20 urinary tube insertion from June 1, 2019 to December 31, 2020 in our hospital were selected. Patients were grouped urinary infection and no infection group according to the culture results of urine, and the clinical data of the 2 groups of patients were collected and compared. Single factor and logistic regression analysis were used to analyze the risk factors of urinary tract infection after retrograde upper urinary lithotripsy.Four hundred ten patients with retrograde upper urinary lithotripsy were included, of whom 62 patients had the urinary tract infection, the incidence of urinary tract infection was 15.12%. There were significant differences in the gender, age, diabetes, stone diameter, duration of urinary tube insertion and duration of surgery between infection and no-infection group (all P < .05). The Escherichia coli (62.90%) was the most commonly seen bacterial in patients with urinary tract infection. Female (odds ratio [OR]: 1.602, 95% confidence interval 95% [CI]: 1.132∼2.472), age >50 years (OR: 2.247, 95% CI: 1.346∼3.244), diabetes (OR: 2.228, 95% CI: 1.033∼3.451), stone diameter ≥2 cm (OR: 2.152, 95% CI: 1.395∼3.099), duration of urinary tube insertion ≥3 days (OR: 1.942, 95% CI:1.158∼2.632), duration of surgery ≥90 minutes (OR: 2.128, 95% CI: 1.104∼3.846) were the independent risk factors for the postoperative urinary tract infection in patients with retrograde upper urinary lithotripsy (all P < .05).The incidence of urinary tract infection in patients undergoing retrograde upper urinary lithotripsy was high, counteractive measures targeted on those risk factors are needed to prevent and reduce the postoperative urinary infection in clinical settings.

Assessing the optimal urine culture for predicting systemic inflammatory response syndrome after percutaneous nephrolithotomy and retrograde intrarenal surgery: results from a systematic review and meta-analysis

Background Systemic inflammatory response syndrome (SIRS) is a dangerous complication after percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS). We aimed to review the diagnostic accuracy of mid steam urine culture (MSUC), pelvic urine culture (PUC) and stone culture (SC) derived from the same cases to predict SIRS after PCNL and/or RIRS. Materials and methods A comprehensive literature search was performed, using MEDLINE, EMBASE, and Cochrane Central Controlled Register of Trials. Sensitivity and specificity were calculated for MSUC, PUC, and SC. The diagnostic odds ratio (DOR) was estimated for each study with a random effect and hierarchical summary receiver operating characteristic (HSROC) model leading to a corresponding 95% Confidence Interval (CI). Overall test accuracy was measured by finding the area under the curve (AUC). An AUC value >0.70 stands for adequate overall accuracy Results The search retrieved 537 papers. After screening, 21 studies involving 5238 patients were included for the meta-analysis. The pooled sensitivity for MSUC was 0.322 (95% CI 0.2228-0.432), and pooled specificity 0.854 (95% CI 0.810-0.889). The DOR was low at 2.780 (95% CI 1.769-4.368), showing poor overall diagnostic accuracy. The pooled sensitivity for PUC was 0.323 (95% CI 0.224-0.440) and specificity 0.931 (95% CI 0.896-0.954). The DOR was 6.377 (95% CI 4.065-10.004), showing a mild overall diagnostic accuracy. The pooled sensitivity for SC was 0.552 (95% CI 0.441-0.658) and specificity 0.847 (95%CI 0.798-0.886). The DOR was 6.820 (95%CI 4.435-10.488), showing mild overall diagnostic accuracy. The AUC for HSROC for MSUC was 0.65, 0.73, and 0.75 for PUC and SC, respectively. Conclusion MSUC is a poor predictor for postoperative SIRS. PUC or SC should be collected during lithotripsy to better predict the possibility of developing postoperative SIRS after PCNL and RIRS.

Predictive Model for Systemic Infection After Percutaneous Nephrolithotomy and Related Factors Analysis

Objectives: To investigate the factors associated with systemic infection after percutaneous nephrolithotomy (PCNL) and establish a predictive model to provide theoretical basis for the prevention of systemic inflammatory response syndrome (SIRS) and urosepsis correlate to percutaneous nephrostomy.

Methods: Patients received PCNL between January 2016 and December 2020 were retrospectively enrolled. All patients were categorized into groups according to postoperative SIRS and urosepsis status. Single factor analysis and multivariate logistic regression analysis were performed to determine the predictive factors of SIRS and urosepsis after PCNL. The nomograms were generated using the predictors respectively and the discriminative ability of was assessed by analyses of receiver operating characteristic curves (ROC curves).

Results: A total of 758 PCNL patients were enrolled in this study, including 97 (12.8%) patients with SIRS and 42 (5.5%) patients with urosepsis. Multivariate logistic regression analysis suggested that there were 5 factors related to SIRS, followed by preoperative neutrophil to lymphocyte ratio (NLR) (odds ratio, OR = 1.721, 95% confidence interval, CI [1.116–2.653], p = 0.014), S.T.O.N.E. score (OR = 1.902, 95% CI [1.473–2.457], p < 0.001), female gender (OR = 2.545, 95% CI [1.563–4.144], p < 0.001), diabetes history (OR = 1.987, 95% CI [1.051–3.755], p = 0.035), positive urine culture (OR = 3.184, 95% CI [1.697–5.974], p < 0.001). And there were four factors related to urosepsis, followed by preoperative NLR (OR = 1.604, 95% CI [1.135–2.266], p = 0.007), S.T.O.N.E. score (OR = 1.455, 95% CI [1.064–1.988], p = 0.019), female gender (OR = 2.08, 95% CI [1.063–4.07], p = 0.032), positive urine culture (OR = 2.827, 95% CI [1.266–6.313], p = 0.011). A nomogram prediction model was established to calculate the cumulative probability of SIRS and urosepsis after PCNL and displayed favorable fitting by Hosmer–Lemeshow test (p = 0.953, p = 0.872). The area under the ROC curve was 0.784 (SIRS) and 0.772 (urosepsis) respectively.

Conclusion: Higher preoperative NLR, higher S.T.O.N.E. score, female gender, and positive urine culture are the most significant predictors of SIRS and urosepsis. Diabetes history is the predictor of SIRS. These data will help identify high-risk individuals and facilitate early detection of SIRS and urosepsis post-PCNL.

Photothermal nanoparticles for ablation of bacteria associated with kidney stones

OBJECTIVE

To determine whether photothermal polymer nanoparticles (NPs) can interface with bacteria associated with kidney stones, generate heat when stimulated with near infrared (NIR) light, and aid in reducing bacterial burden.

METHODS

Two types of kidney stones, artificial, and those removed during percutaneous nephrolithotomy (PCNL), were inoculated with Escherichia coli (E. coli) and then incubated with NPs composed of FITC-labeled Poly[4,4-bis(2-ethylhexyl)-cyclopenta[2,1-b;3,4-b']-dithiophene-2,6-diyl-alt-2,1,3-benzoselenadiazole-4,7-diyl] (PCPDTBSe). Association of the PCPDTBSe NPs was evaluated using fluorescence microscopy. Infected stones were incubated with NPs and exposed to 800 nm light to generate temperature increases from 25.4 to 68.6 °C on the stones. Following photothermal treatment, the stones were homogenized and the bacteria was enumerated via colony counting assays to evaluate the bactericidal effect. The photothermal effect was also evaluated using scanning electron microscopy of the treated biofilms.

RESULTS

Both kidney stone types sequestered E. coli. Control stones and stones treated with laser only had growth of numerous bacterial colonies, while stones exposed to NPs and laser grew significantly less, or none (p = 0.02).

CONCLUSIONS

The polymer NPs interface with E. coli on artificial and patient-derived kidney stones, and they can impart a bactericidal effect, when stimulated with NIR to generate heat. This technique may possibly be extended to treating infected kidney stones in patients.

Risk factors and prediction model of urosepsis in patients with diabetes after percutaneous nephrolithotomy

Objective

To analyze the risk factors of patients with diabetes mellitus (DM) and urosepsis after percutaneous nephrolithotomy (PCNL) for upper urinary tract stones and to develop a nomogram to predict postoperative urosepsis according to the risk factors.

Methods

The data of patients with type 2 diabetes who underwent one-stage PCNL due to upper urinary tract stones were retrospectively analyzed. The risk factors of patients with postoperative urosepsis were evaluated by univariate and multivariate logistic regression analysis, and the nomogram prediction model was developed according to the regression coefficient.

Results

One-stage PCNL was successfully completed in 241 patients with DM, and urosepsis occurred in 41 (17.0%) patients after PCNL. Based on multivariate logistic regression analysis, the independent risk factors associated with postoperative urosepsis included preoperative leukocyte elevation (OR = 3.973, P = 0.005), positive urine nitrite (OR = 3.697, P = 0.010), and positive urine culture (OR = 3.562, P = 0.002). According to the results of the logistic regression analysis model, staghorn stones (OR = 2.049, P < 0.1) and complete intraoperative stone clearance (OR = 0.431, P < 0.1), were used to develop the nomogram. Internal validation of the nomogram showed that the concordance index (C-index) was 0.725. Additionally, the Hosmer–Lemeshow test was performed, P = 0.938 > 0.05.

Conclusion

Preoperative leukocyte elevation, positive urine nitrite, and positive urine culture are independent risk factors for urosepsis after one-stage PCNL for patients with DM with upper urinary tract stones. The nomogram, which is based on independent risk factors that combine stone morphology and intraoperative stone clearance, can help predict the risk of postoperative urosepsis.

Does the duration between urine culture and percutaneous nephrolithotomy affect the rate of systemic inflammatory response syndrome postoperatively?

This study aimed to evaluate the preoperative and intraoperative factors that may cause systemic inflammatory response syndrome (SIRS) after percutaneous nephrolithotomy (PCNL) and to investigate the effect of the duration between urine culture (UC) and operation on postoperative SIRS. Three hundred and fifty-six patients who had PCNL between January 2015 and June 2019 were retrospectively included in the study. UC was obtained from all patients before the operation and during the puncture at the beginning of the operation. Postoperatively, patients were closely monitored for fever and other signs of SIRS. The post-PCNL SIRS incidence was 7%. In univariable and multivariable analyses, the rate of ipsilateral PCNL history, recurrent urinary tract infection (UTI) history, operation time and the length of hospital stay were significant predictive factors for SIRS. The duration between UC and PCNL was not a statistically significant variable in both univariable and multivariable analysis. Our study concluded that the duration between UC and PCNL is not an influential factor for post-PCNL SIRS. Clarifying this issue may be possible with prospective studies in which the effects of factors such as ipsilateral PCNL history and recurrent urinary tract infection history which has been proven to be risk factors for post-PCNL SIRS are restricted.

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.

European Association of Urology Section of Urolithiasis and International Alliance of Urolithiasis Joint Consensus on Percutaneous Nephrolithotomy

CONTEXT

Although percutaneous nephrolithotomy (PCNL) has been performed for decades and has gone through many refinements, there are still concerns regarding its more widespread utilization because of the long learning curve and the potential risk of severe complications. Many technical details are not included in the guidelines because of their nature and research protocol.

OBJECTIVE

To achieve an expert consensus viewpoint on PCNL indications, preoperative patient preparation, surgical strategy, management and prevention of severe complications, postoperative management, and follow-up.

EVIDENCE ACQUISITION

An international panel of experts from the Urolithiasis Section of the European Association of Urology, International Alliance of Urolithiasis, and other urology associations was enrolled, and a prospectively conducted study, incorporating literature review, discussion on research gaps (RGs), and questionnaires and following data analysis, was performed to reach a consensus on PCNL.

EVIDENCE SYNTHESIS

The expert panel consisted of 36 specialists in PCNL from 20 countries all around the world. A consensus on PCNL was developed. The expert panel was not as large as expected, and the discussion on RGs did not bring in more supportive evidence in the present consensus.

CONCLUSIONS

Adequate preoperative preparation, especially elimination of urinary tract infection prior to PCNL, accurate puncture with guidance of fluoroscopy and/or ultrasonography or a combination, keeping a low intrarenal pressure, and shortening of operation time during PCNL are important technical requirements to ensure safety and efficiency in PCNL.

PATIENT SUMMARY

Percutaneous nephrolithotomy (PCNL) has been a well-established procedure for the management of upper urinary tract stones. However, according to an expert panel consensus, core technical aspects, as well as the urologist's experience, are critical to the safety and effectiveness of PCNL.

The predictive and diagnostic ability of IL-6 for postoperative urosepsis in patients undergoing percutaneous nephrolithotomy

The aim of this study is to investigate the predictive and diagnostic ability of interleukin-6 (IL-6) for postoperative urosepsis in patients undergoing percutaneous nephrolithotomy (PCNL). 90 patients undergoing PCNL between April 2019 and September 2019 were studied. 16 patients progressed to urosepsis (EXP1 group, n = 16) and 74 patients did not (CON group, n = 74); demographic and perioperative data were compared between these two groups. 25 patients who progressed to postoperative urosepsis without receiving the test of IL-6 between March 2018 and March 2019 were enrolled (EXP2 group, n = 25); demographic and perioperative data were compared between EXP1 group and EXP2 group. Compared with CON group, EXP1 group showed higher serum levels of IL-6 (p < 0.001) and neutrophil (p < 0.001) at postoperative hour two; higher serum levels of IL-6 (p < 0.001), procalcitonin (PCT) (p < 0.05), white blood cell (WBC) (p < 0.05), and neutrophil (p < 0.001) on postoperative day one; higher serum levels of PCT (p < 0.05) and WBC (p < 0.05) on postoperative day three. ROC curves showed IL-6 (AUC = 1.000) at postoperative hour two and PCT (AUC = 0.954) on postoperative day three. Compared with EXP2 group, EXP1 group showed shorter time to intervene (p < 0.001), a shorter postoperative hospital stay (p < 0.001), and a lower incidence rate of severe urosepsis (p < 0.05). There were different diagnostic abilities of IL-6, PCT, WBC, and neutrophil for postoperative urosepsis at different time points, and IL-6 was greatly valuable as a predictive and early diagnosing biomarker for postoperative urosepsis in patients undergoing PCNL at postoperative hour two and on postoperative day one.

The retrospective study of perioperative application of dexamethasone and furosemide for postoperative anti-inflammation in patients undergoing percutaneous nephrolithotomy

Objectives

To investigate whether the perioperatively combined application of dexamethasone and furosemide could alleviate the inflammation in patients undergoing percutaneous nephrolithotomy (PCNL).

Patients and methods

147 patients undergoing PCNL between November 2018 and October 2019 were enrolled in the study. 77 patients accepted a single dose of dexamethasone and furosemide administration (EXP group, n = 77), and 70 patients did not (CON group, n = 70). Demographic and perioperative data, inflammatory markers including interleukin-6 (IL-6) and procalcitonin (PCT), and clinical outcomes were compared between the two groups.

Results

Compared with the CON group, the incidence rate of urosepsis of the EXP group were significantly lower (11.69% vs. 24.29%, p = 0.046). 3 patients developed severe urosepsis in the EXP group, while 5 patients developed severe urosepsis in the CON group. Compared with those in the CON group, the patients with postoperative urosepsis in the EXP group showed lower serum levels of IL-6 at postoperative hour two (p = 0.045) and at postoperative day one (p = 0.031) and lower serum levels of PCT at postoperative day one (p = 0.015). There was a better clinical outcome of a shorter postoperative hospital stay (p = 0.015) in patients with postoperative urosepsis in the EXP group than in those in the CON group.

Conclusion

The perioperatively combined application of dexamethasone and furosemide was beneficial for alleviating postoperative inflammatory reaction and caused a better clinical outcome of a shorter postoperative hospital stay.

Predictors of urosepsis in struvite stone patients after percutaneous nephrolithotomy

Purpose

This study aims to identify clinical factors that may predispose struvite stone patients to urosepsis following percutaneous nephrolithotomy (PCNL).

Materials and Methods

A retrospective review was conducted on patients who received PCNL for struvite stones. The Systemic Inflammatory Response Syndrome (SIRS) criteria and quick-Sepsis Related Organ Failure Assessment (q-SOFA) criteria were used to identify patients who were at an increased risk for urosepsis. Statistical analysis was performed using Fisher's exactness test, Wilcoxon rank test, and logistic regression.

Results

Chart review identified 99 struvite stone patients treated with PCNL. Post-operatively, 40 patients were SIRS positive (≥2 criteria) and/or q-SOFA positive (score ≥2). Using SIRS as an approximation for urosepsis, longer operative times (p<0.001), higher pre-operative white blood cell counts (p=0.01), greater total stone surface area (p<0.0001), and pre-operative stenting (OR, 5.75; p=0.01) were identified as independent risk factors for urosepsis. Multivariate analysis demonstrated pre-operative stenting (OR, 1.46; p=0.01) to be a risk factor. With q-SOFA, univariable analysis found that antibiotic use within 3 months prior to a PCNL (OR, 4.44; p=0.04), medical comorbidities (OR, 4.80; p=0.02), longer operative times (p<0.001), lengthier post-operative hospitalization (p<0.01), and greater total stone surface area (p<0.0001) were risk factors for urosepsis. Multivariate analysis revealed that bladder outlet obstruction (OR, 2.74; p<0.003) and pre-operative stenting (OR, 1.27; p=0.01) significantly increased odds of being q-SOFA positive.

Conclusions

Several risk factors for urosepsis following PCNL for struvite stones have been identified. These risk factors should be taken into consideration in peri-operative care to mitigate the risks of urosepsis.

Impact Factors and an Efficient Nomogram for Predicting the Occurrence of Sepsis after Percutaneous Nephrolithotomy

Introduction

To describe the clinical parameters of urinary stones and investigate the preoperative predictors of sepsis in patients following percutaneous nephrolithotomy (PCNL). Patients and Methods. A retrospective study of patients who underwent PCNL between August 2017 and December 2019 was performed. The patients were divided into the sepsis and nonsepsis groups according to whether they had sepsis, and their data were compared for further analysis.

Results

Fifteen (6.1%) patients matching in age, gender, body mass index (BMI), and the number of access variables were included in the sepsis group. The multivariate analysis demonstrated that the staghorn calculi (OR: 12.206, P < 0.001) and positive midstream urine culture (OR: 16.505, P < 0.001) were independent risk factors of sepsis, while preoperative renal fistula (OR: 0.122, P < 0.001) was a protective factor of sepsis. The three factors were ultimately selected to develop a nomogram to predict the probability of sepsis. The new nomogram was well calibrated and had higher diagnostic accuracy (the area under the curve: 0.916).

Conclusions

Our study reveals that patients with complex stones and positive bacteriuria are associated with a significantly high risk of sepsis after surgery. The removal of obstruction before operation under certain conditions might be a reliable protective factor of sepsis.

Study on risk factors, bacterial species, and drug resistance of acute pyelonephritis associated with ureteral stent after percutaneous nephrolithotomy

The purpose of this study is to explore the risk factors, bacterial species, and drug resistance of acute pyelonephritis (AP) associated with ureteral stent after percutaneous nephrolithotomy (PCNL) and to provide reference for clinical intervention. The clinical data of 415 patients with indwelling ureteral stent after PCNL from December 2016 to May 2019 were analyzed retrospectively. The patients were divided into infection group (n = 54) and non-infection group (n = 361) according to whether patients had AP. Patients' clinical data, blood and urine bacterial culture, and drug sensitivity were collected and analyzed. The incidence of AP associated with ureteral stent after PCNL was 13.01% and diabetes mellitus (P = 0.001), postoperative stone residue (P = 0.002), urinary leucocytes ≥ 100/HP (P = 0.018), positive urine culture results (P = 0.001), ureteral stent retention time ≥ 8 weeks (P = 0.004), and high S.T.O.N.E. score (P = 0.014) are independent risk factors for it. Escherichia coli (40.54%, 47.82%), Klebsiella pneumoniae (16.21%, 15.21%), Pseudomonas aeruginosa (10.81%, 4.34%), Enterococcus faecalis (21.6%, 19.56%), and epidermis Staphylococci (10.81%, 13.33%) are the main pathogens in blood and urine. The main sensitive drugs of pathogenic bacteria are imipenem, meropenem, tigecycline, piperacillin/tazobactam, ceftazidime, linezolid, teicoplanin, levofloxacin, vancomycin, tigecycline, etc., while levofloxacin, norfloxacin, penicillin G, first, and second-generation cephalosporins showed a strong drug resistance rate (> 70%). This study found that diabetes, postoperative stone residuals, urinary leukocytes ≧ 100 cells/HP, positive urine culture results, ureteral stent indwelling time ≧ 8 weeks, and high S.T.O.N.E. score were independent of AP associated with ureteral stent after PCNL risk factors and Escherichia coli is the main pathogenic bacteria and shows drug resistance.

The Application of Retrograde Intrarenal Surgery to Remove a Single Large Kidney Stone During Pregnancy

Purpose

To report the application and outcome of retrograde intrarenal surgery (RIRS) to remove a large kidney stone during pregnancy.

Patient and Methods

A 30-year-old woman presented with an infected kidney stone (3 cm in size) at 4 weeks of pregnancy. We decided to remove the stone due to the possibility of obstruction and infection and chose to carry out this procedure by RIRS. In order to avoid complications associated with anesthetic, the surgery was carried out after the infection had cleared and when the patient had entered the second trimester of pregnancy. First, we used an ureteral access sheath and semi-rigid ureteroscopy to evaluate the ureteral lumen. We confirmed that the ureteral access sheath had been positioned appropriately by direct visualization with a flexible ureterorenoscope. The procedure was then carried out with a radiation-free protocol and without fluoroscopy. Ho-YAG laser lithotripsy was used to fragment the stones, and these fragments were then removed in a stone basket. The patient required three sessions of RIRS to remove the stone in its entirety; during this time, the patient was 18-29 weeks into her pregnancy. During each session, we removed approximately 30% of the stone. The patient developed fever after the first operation but responded fully to antibiotics. There were no perioperative complications, and the patient only remained in hospital for 3 days. The male infant was delivered by caesarian section at 37 weeks of pregnancy without any health complications.

Results and Conclusion

We successfully removed a large kidney stone from a pregnant patient using an ureteral access sheath and RIRS without fluoroscopy. There were no complications indicating that this procedure can be carried out safely during pregnancy.

Risk factors for the fever after percutaneous nephrolithotomy: a retrospective analysis

Background

It’s very common to see the onset of fever after percutaneous nephrolithotomy (PCNL), it’s necessary to analyze the risk factors for the fever following PCNL, and to provide evidence for infection prevention after PCNL.

Methods

A total of 546 adult PCNL patients were included as study subjects and retrospective studies were performed. We collected clinical data of patients using a prospectively designed database. Univariate and multivariate logistic regression analyses were performed to identify the potential risk factors for the fever after PCNL.

Results

Of the included 546 PCNL patients, there were 82 fever patients and 464 no-fever patients following PCNL. Escherichia coli and Proteus mirabilis are the two most common infectious bacteria. Preoperative urinary tract infection (OR =4.38, 95% CI: 1.15–9.53), multiple access (OR =5.31, 95% CI: 1.23–10.75), diabetes (OR =4.97, 95% CI: 1.37–9.86), length of operation ≥60 min (OR =5.67, 95% CI: 2.24–13.42), estimated blood loss in PCNL ≥500 mL (OR=2.78, 95% CI: 2.32–3.61) were the independent risk factors associated with postoperative infection.

Conclusions

Effective control of urinary tract infection, reduction of access number, strict control of blood glucose, length of operation control, reduction of intraoperative bleeding should be considered as measures to prevent postoperative fever for patients with PCNL.

Predicting and comparing postoperative infections in different stratification following PCNL based on nomograms

To discuss the mechanisms of infection complications in different degrees after percutaneous nephrolithotomy (PCNL) through predicting and comparing post-PCNL infections based on nomograms, a retrospective cohort study was conducted among 969 cases who underwent PCNL from Dec 5, 2016 to Dec 25, 2017 in Kunming, Yunnan Province. We examined clinical features, urine routine, blood routine, blood biochemistry, imaging studies and operative information and recorded the examination results before surgery for univariate and multivariate logistic regression. We applied receiver operating characteristic curves, calibration curves, accuracy, specificity, sensitivity, positive predictive value and negative predictive value to evaluate and compare the models. Nomograms were used to visualize the different degrees of postoperative infection complications. The risk scores of the three groups were compared by diabetes mellitus distribution. Our results suggest that the more severe the infection is, the more accurate the model predicts and that the occurrence of severe infection mostly is related to the patients' homeostasis. Hence, we developed an online post-PCNL sepsis dynamic nomogram which can achieve visualization and dynamically predict the incidence of sepsis in postoperative patients.

A preoperative nomogram for sepsis in percutaneous nephrolithotomy treating solitary, unilateral and proximal ureteral stones

Background

Postoperative sepsis is a lethal complication for percutaneous nephrolithotomy (PCNL). An early predictive model combined local and systemic conditions is urgently needed to predict infectious events. We aim to determine the preoperative predictors of sepsis after PCNL in patients with unilateral, solitary, and proximal ureteral stones.

Methods

A total of 745 patients who underwent PCNL between January 2012 and December 2018 were retrospectively enrolled. Sepsis was defined based on the International Sepsis Definitions in 2001, and the preoperative factors were compared between the non-sepsis and sepsis groups. Univariable analysis and multivariable logistic regression analysis were conducted to determine the predictors for sepsis after PCNL. A nomogram was generated using the predictors.

Results

In this study, 35 patients (4.7%) developed sepsis after PCNL. Univariate analysis showed that post-PCNL sepsis was associated with the female, lower albumin, higher globulin, lower albumin globulin ratio (AGR < 1.5), preoperative fever, leukocytosis (WBC ≥ 10,000 cells/μL), positive urine culture, leukocyturia (≥50 cells/μL) and positive urine nitrite. Multivariate logistic regression analysis suggested that AGR < 1.5 (odds ratio [OR] = 5.068, 95% confidence interval [CI] [1.135-22.624], P = 0.033), positive urine culture (OR = 3.243, 95% CI [1.162-9.047], P = 0.025), leukocytosis (OR = 3.706, 95% CI [1.444-9.512], P = 0.006) and female (OR = 2.529, 95% CI [1.127-5.672], P = 0.024) were independent risk factors for sepsis. A nomogram was generated and displayed favorable fitting (Hosmer-Lemeshow test P = 0.797), discrimination (area under receiver operating characteristic curve was 0.807), and clinical usefulness by decision curve analysis.

Conclusions

Patients with certain preoperative characteristics, such as female, lower AGR, positive urine culture, and leukocytosis, who undergo PCNL may have a higher risk of developing sepsis. A cautious preoperative evaluation and optimized treatment strategy should be considered in these patients to minimize infectious complications.

Bacterial spectrum and antibiotic resistance of urinary tract infections in patients treated for upper urinary tract calculi: a multicenter analysis

The purpose of this study is to collect information on the bacterial resistance to antibiotics of bacteria isolated from urine cultures of patients treated for upper urinary tract calculi. Data of patients with urinary tract infection and urolithiasis were retrospectively reviewed to collect information on age, gender, stone size, location, hydronephrosis, procedure of stone removal and antibiotic treatment, identification and susceptibility of pathogens, symptoms, and infectious complications. A total of 912 patients from 11 centers in 7 countries (Bulgaria, Greece, Italy, North Macedonia, Spain, and Turkey) were studied. Mean age was 54 ± 16 years and M/F ratio 322/590. Out of 946 microbial isolates, the most common were E. coli, Gram-positive, KES group (Klebsiella, Enterobacter, Serratia), Proteus spp., and P. aeruginosa. Carbapenems, piperacillin/tazobactam and amikacin showed low resistance rates to E. coli (2.5%, 7%, and 3.6%) and Proteus spp. (7.7%, 16%, and 7.4%), but higher rates were observed with Klebsiella spp., P. aeruginosa, and Gram-positive. Fosfomycin had resistance rates less than 10% to E. coli, 23% to KES group, and 19% to Gram-positive. Amoxicillin/clavulanate, cephalosporins, quinolones, and TMP/SMX showed high resistance rates to most bacterial strains. High rates of antibiotic resistance were observed in patients candidate to stone treatment from South-Eastern Europe. The empirical use of antibiotics with low resistance rates should be reserved to the most serious cases to avoid the increase of multidrug resistant bacteria. Basing on our results, carbapenems, piperacillin/tazobactam, and amikacin may be a possible option for empiric treatment of urinary stone patients showing systemic symptoms.

Risk Factors for Urosepsis after Minimally Invasive Percutaneous Nephrolithotomy in Patients with Preoperative Urinary Tract Infection

The purpose of this study was to assess risk factors of urosepsis after minimally invasive percutaneous nephrolithotomy (MPCNL) for the treatment of upper urinary tract stones in patients with preoperative urinary tract infection (UTI) and to explore preventive measures. Between 2008 and 2016, patients with preoperative UTI who underwent MPCNL for upper urinary tract stones were retrospectively collected. Patients were divided into nonurosepsis and urosepsis groups. Perioperative outcomes of all patients were evaluated and compared between the two groups. Risk factors for post-MPCNL urosepsis were investigated using univariate and multivariate regression analysis. A total of 843 patients including 22 patients with postoperative urosepsis (urosepsis group) and 821 patients without urosepsis (nonurosepsis group) were finally included in this study. All patients with postoperative urosepsis were cured and discharged after treatment. In univariate analysis it was demonstrated that the incidence of urosepsis after MPCNL was significantly correlated with channel size (P=0.001), surgical time (P=0.003), as well as the tear of the collection system and percutaneous renal channel crossing the renal papilla (P=0.004). Moreover, multivariate analysis showed that smaller channel size (OR = 11.192, 95% CI: 2.425-51.650, P=0.002), longer surgical time (OR = 6.762, 95% CI: 1.712-17.844, P=0.008), and tear of collection system and percutaneous renal channel crossing the renal papilla (OR = 5.531, 95% CI 1.228-14.469, P=0.012) were independent risk factors for urosepsis following MPCNL in patients with preoperative UTI. In conclusion, in patients with preoperative UTI undergoing MPCNL for upper urinary tract stones, smaller channel size, prolonged operation time, as well as tear of the collection system and percutaneous renal channel crossing the renal papilla are independent risk factors for postoperative urosepsis. Therefore, it is indicated that, in clinical practice, it is of great significance to choose appropriate channel size and avoid renal injury and control surgical time to prevent the urosepsis after MPCNL in patients with preoperative UTI.

Contemporary best practice in the management of staghorn calculi

Staghorn calculi are complex renal stones that occupy the majority of the renal collecting system. These stones are associated with high morbidity and can lead to recurrent urinary tract infections, urosepsis, renal deterioration, and death if left untreated. Managing patients with staghorn calculi can be challenging. Fortunately, advances in technology and endourology techniques have enabled urologists to effectively treat these stones with minimal morbidity to the patient. This article describes the contemporary best practices in the initial evaluation, management, and follow up of patients with staghorn calculi to help the practicing urologist navigate this complex condition.

Predictive factors of infectious complications in the postoperative of percutaneous nephrolithotomy

OBJECTIVE

Infectious complications (IC) following percutaneous nephrolithotomy surgery (PCNL) can be life-threatening. Our objective was to analyse preoperative predictors of IC in PCNL.

MATERIALS AND METHODS

A total of 203 patients who underwent PCNL were included in a prospective study between January 2013 and February 2016. A postoperative IC was defined as urinary infection/pyelonephritis, systemic inflammatory response syndrome or sepsis. The variables analysed were age, gender, number, size(cm) and side of stone; Hounsfield units,diabetes (insulin dependent or not), preoperative culture, isolated bacteria, multitract, bodymass index and surgical time (min). A multivariate forward stepwise (logistic regression) was performed.

RESULTS

IC occurred in 30 patients (14.8%): 9 (4.4%) had urinary infection, 14 (6.9%) systemic inflammatory response syndrome and 7 (3.5%) sepsis. In addition, 13 (43.3%) had negative preoperative urine culture, 15 (50%) positive and in 2 (6.7%) was not available. On the logistic regression analysis, stone size (cm), insulin dependent diabetes and female sex were independently associated with increased risk of IC (odds ratio [OR] 1.03, 14.6 and 7.8, respectively; P=.0001).

CONCLUSIONS

Patients with large stone burdens, insulin diabetes condition and female gender, should be counselled properly regarding postoperative infection risks and closely followed up to diagnose IC (specially sepsis) soon enough. Negative preoperative urine culture seems not reliable enough to exclude an infectious complication according to our results.

Propensity Score-Matched Analysis Comparing Retrograde Intrarenal Surgery with Percutaneous Nephrolithotomy for Large Stones in Patients with a Solitary Kidney

PURPOSE

To evaluate the clinical efficacy, safety, and cost of retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PCNL) in the treatment for large renal stones in patients with a solitary kidney.

PATIENTS AND METHODS

In this study, 117 patients with a solitary kidney who had undergone PCNL or RIRS for renal stones larger than 2 cm between January 2010 and December 2016 were retrospectively evaluated. The patients' demographic data, clinical characteristics, and perioperative outcomes were collected through a review of their medical records. Forty-three patients treated with PCNL were compared to 43 patients treated with RIRS by propensity score-matched analysis. The stone-free rate, retreatment rate, complication rate, and efficacy quotient (EQ) were assessed in both groups.

RESULTS

Initial stone-free rate of the PCNL group after a single procedure was significantly higher compared with the RIRS group (74.42% vs 34.88%, p < 0.001), whereas there was no significant difference in the final stone-free rate after repeated procedures (90.70% vs 88.37%, p = 0.713). PCNL had a significantly lower retreatment rate than RIRS (16.28% vs 63.79%, p < 0.001), and the PCNL group underwent fewer procedures than the RIRS group (p < 0.001). Thus, PCNL group had a higher EQ (78.00% vs 53.52%). Although cost per procedure of PCNL was significantly higher compared with RIRS (p < 0.001), the total costs were comparable. Complication rate of RIRS was lower compared with PCNL with no statistical significance (p = 0.193), and acute kidney injury rates were also comparable (PCNL vs RIRS: 13.95% vs 6.98%, p = 0.533).

CONCLUSIONS

With fewer repeated surgical procedures, higher EQ, and comparable total costs, PCNL is recommended as the first choice for the treatment of large renal calculi in patients with a solitary kidney. As for specific indications such as anticoagulant drugs, RIRS is a safer choice with fewer complications and acceptable final stone-free rate.