Early and rapid prediction of postoperative infections following percutaneous nephrolithotomy in patients with complex kidney stones

International Alliance of Urolithiasis (IAU) consensus on miniaturized percutaneous nephrolithotomy

Over the past three decades, there has been increasing interest in miniaturized percutaneous nephrolithotomy (mPCNL) techniques featuring smaller tracts as they offer potential solutions to mitigate complications associated with standard PCNL (sPCNL). However, despite this growing acceptance and recognition of its benefits, unresolved controversies and acknowledged limitations continue to impede widespread adoption due to a lack of consensus on optimal perioperative management strategies and procedural tips and tricks. In response to these challenges, an international panel comprising experts from the International Alliance of Urolithiasis (IAU) took on the task of compiling an expert consensus document on mPCNL procedures aimed at providing urologists with a comprehensive clinical framework for practice. This endeavor involved conducting a systematic literature review to identify research gaps (RGs), which formed the foundation for developing a structured questionnaire survey. Subsequently, a two-round modified Delphi survey was implemented, culminating in a group meeting to generate final evidence-based comments. All 64 experts completed the second-round survey, resulting in a response rate of 100.0%. Fifty-eight key questions were raised focusing on mPCNLs within 4 main domains, including general information (13 questions), preoperative work-up (13 questions), procedural tips and tricks (19 questions), and postoperative evaluation and follow-up (13 questions). Additionally, 9 questions evaluated the experts' experience with PCNLs. Consensus was reached on 30 questions after the second-round survey, while professional statements for the remaining 28 key questions were provided after discussion in an online panel meeting. mPCNL, characterized by a tract smaller than 18 Fr and an innovative lithotripsy technique, has firmly established itself as a viable and effective approach for managing upper urinary tract stones in both adults and pediatrics. It offers several advantages over sPCNL including reduced bleeding, fewer requirements for nephrostomy tubes, decreased pain, and shorter hospital stays. The series of detailed techniques presented here serve as a comprehensive guide for urologists, aiming to improve their procedural understanding and optimize patient outcomes.

Radiomics and Clinical Features for Distinguishing Kidney Stone-Associated Urinary Tract Infection: A Comprehensive Analysis of Machine Learning Classification

Background

This study investigated the abilities of radiomics and clinical feature models to distinguish kidney stone-associated urinary tract infections (KS-UTIs) using computed tomography.

Methods

A retrospective analysis was conducted on a single-center dataset comprising computed tomography (CT) scans and corresponding clinical information from 461 patients with kidney stones. Radiomics features were extracted from CT images and underwent dimensionality reduction and selection. Multiple machine learning (Three types of shallow learning and four types of deep learning) algorithms were employed to construct radiomics and clinical models in this study. Performance evaluation and optimal model selection were done using receiver operating characteristic (ROC) curve analysis and Delong test. Univariate and multivariate logistic regression analyzed clinical and radiomics features to identify significant variables and develop a clinical model. A combined model integrating radiomics and clinical features was established. Model performance was assessed by ROC curve analysis, clinical utility was evaluated through decision curve analysis, and the accuracy of the model was analyzed via calibration curve.

Results

Multilayer perceptron (MLP) showed higher classification accuracy than other classifiers (area under the curve (AUC) for radiomics model: train 0.96, test 0.94; AUC for clinical model: train 0.95, test 0.91. The combined radiomics-clinical model performed best (AUC for combined model: train 0.98, test 0.95). Decision curve and calibration curve analyses confirmed the model's clinical efficacy and calibration.

Conclusions

This study showed the effectiveness of combining radiomics and clinical features from CT scans to identify KS-UTIs. A combined model using MLP exhibited strong classification abilities.

Hydroxyproline increases inflammation and Uropathogenic E. coli (UPEC) infection in female rats

Calcium oxalate (CaOx) kidney stones may be associated with urinary tract infections (UTIs). However, the mechanisms for this association are not well-established. The objective of this study was to investigate the effect of oxalate on immunity and UTI development in vivo. Female Sprague-Dawley rats were fed a control diet for 3 days before continuing this diet or starting a 5% Hydroxy-L-proline diet (HLP; oxalate precursor) for 7 days. Rats were subsequently infected transurethrally with Uropathogenic E. coli (UPEC, a bacterium that causes UTI) and sacrificed 3 days later. Urine, blood, kidney, and bladder samples were collected. Urinary oxalate levels, renal CaOx crystal deposition, inflammatory markers, and the bacterial load were assessed using ion chromatography-mass spectrometry, immunohistochemistry, qRT-PCR, western blotting, enzyme-linked immunosorbent assays, or colony forming unit assays. Animals fed HLP and infected with UPEC had a significant increase in urinary oxalate levels, renal CaOx deposition, pro-inflammatory macrophages, pro-inflammatory cytokines, and bacterial loads compared to animals fed the control diet with UPEC infection. In addition, HLP-fed animals had significantly reduced anti-inflammatory renal macrophages and anti-inflammatory cytokine levels in their plasma, urine, and kidneys. These findings suggest that oxalate may play a novel role in the propagation of UTI development.

The role of early use of Carbapenems perioperatively for urolithiasis with ESBL-producing Escherichia coli

BACKGROUND

Urolithiasis combined with ESBL-producing E. coli is often difficult to control and leads to higher postoperative infection-related complications. This study was aim to explore the efficacy and necessity for early use of carbapenem antibiotics perioperatively in urolithiasis patients with urinary tract infections caused by ESBL-producing E. coli.

METHODS

The study included a total of 626 patients who were separated into two groups: Group I (the ESBL-producing E. coli group) and Group II (the non-ESBL-producing E. coli group). Antibiotic susceptibility testing was performed and the two groups induced postoperative infection-related events were recorded. the efficacy of perioperative antibiotics was evaluated.

RESULTS

All strains of E. coli in our research were sensitive to Carbapenems antibiotics. In addition to Carbapenems, the resistance rates of ESBL-producing E. coli to 6 other commonly used antibiotics were higher than those of non-ESBL-producing strains. Based on the preoperative antibiotic susceptibility test for the ESBL-producing E. coli group and the qSOFA score, the Carbapenems were more effective than the β-lactamase inhibitors (p = 0.08), while for the non-ESBL-producing E. coli group, there was no difference in the treatment effects between Carbapenems, β-lactamase inhibitors, Ceftazidime and Quinolones (p = 0.975).

CONCLUSIONS

Carbapenem antibiotics significantly reduced the incidence of postoperative infection-related events compared with other types of antibiotics for ESBL-producing E. coli infections in patient with urolithiasis.

Prediction of systemic inflammatory response syndrome and urosepsis after percutaneous nephrolithotomy by urine culture, stone culture, and renal pelvis urine culture: Systematic review and meta-analysis

Background

Percutaneous nephrolithotomy (PCNL) is thought to have an increased risk of infectious complications. This study evaluates the predictability of preoperative midstream urine culture (PMUC), stone culture (SC), and renal pelvis urine culture (RPUC) for post-PCNL systemic inflammatory response syndrome (SIRS) or urosepsis.

Method

After literature search in electronic databases (Embase, PubMed, Ovid, Science Direct, and Springer), studies were selected by following precise eligibility criteria. The quality of included studies was assessed, and meta-analyses of proportions were performed to seek culture positivity rates and incidence rates of post-PCNL SIRS/urosepsis. Meta-analyses of odds ratios (OR) were performed to evaluate the odds of positivity between SC and PMUC or RPUC, and the odds of post-PCNL SIRS/urosepsis with SC versus PMUC or RPUC.

Results

Nineteen studies (4829 patients) were included. Positivity rates of PMUC, SC, and RPUC were 16 % [95 % CI: 12, 20], 21 % [95 % CI: 16, 26] and 10 % [95 % CI: 7, 14] respectively. The odds of positivity were significantly higher for SC compared to PMUC (OR 1.37 [95%CI: 1.02, 1.84]; p = 0.037) or RPUC (OR 1.65 [95%CI: 1.25, 2.18] p < 0.0001). The incidence of post-PCNL SIRS and urosepsis was 21 % [95%CI: 17, 25] and 6 % [95%CI: 3, 10] respectively. The odds of post-PCNL SIRS were significantly higher with SC compared to PMUC (OR 2.45 [95%CI: 1.12, 5.38] p = 0.025) or RPUC (OR 2.10 [95%CI: 1.33, 3.30]; p = 0.001) positivity. The odds of developing urosepsis after PCNL were not significantly different between SC and PMUC positivity (OR 1.874 [95 % CI: 0.943, 3.723]; p = 0.073).

Conclusion

The risk of post-PCNL SIRS is found higher with SC than with PMUC or RPUC positivity. However, the risk of urosepsis may not be different between SC and PMUC.

Characteristics of Bacteria in Urine and Stones from Patients Treated with Percutaneous Nephrolithotomy and Association with Postoperative Infection

Background

The purpose of this study was to identify bacterial differences between urine cultures (UC) and stone cultures (SC) in patients with complex kidney stones and to determine any correlation with post-percutaneous nephrolithotomy Systemic Inflammatory Response Syndrome (SIRS).

Methods

Perioperative data of 1055 patients with complex kidney stones treated with first-stage Percutaneous Nephrolithotomy (PCNL) from September 2016 until September 2021 were included. Preoperative mid-stream urine samples and surgically obtained stone material were subjected to bacterial culture and antibiotic sensitivity tests. Preoperatively, antibiotic usage was determined by the UC or local bacterial resistance patterns. After PCNL treatment, antibiotic selection was guided by stone bacterial culture result and clinical symptoms. The effect of different preoperative antibiotic regimens based on urine cultures and postoperative antibiotic treatment based on stone cultures were assessed.

Results

Positive stone cultures (SC+) were significantly more common than positive urine cultures (UC+) (31.9% vs 20.9%, p < 0.05). Escherichia coli (E. coli) was the most common uropathogen in both urine (54.3%) and stones (43.9%). The difference was statistically significant (p < 0.05). Moreover, UC+SC-, UC-SC+, UC+SC+, and preoperative serum creatinine were independent risk factors of postoperative SIRS. The incidence of SIRS in the UC+SC+ patients with different bacteria in stones and urine (51.6%) was higher than that in other culture groups. The antibiotic resistance of E. coli inside the stone was increased when prolonged preoperative antibiotics were administered to UC+ patients.

Conclusion

The bacterial spectrum and positive outcome of culture in urine and stones were significantly different. The incidence of postoperative SIRS was highest in patients with UC+SC+ but with different bacteria strains. Prolonged pre-surgical antibiotic treatment apparently induced higher drug resistance for bacteria inside the stone.

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.

The value of IL-6, PCT, qSOFA, NEWS, and SIRS to predict septic shock after Percutaneous nephrolithotomy

BACKGROUND

There are numerous methods available for predicting sepsis following Percutaneous Nephrolithotomy. This study aims to compare the predictive value of Quick Sequential Organ Failure Assessment (qSOFA), Systemic Inflammatory Response Syndrome (SISR), National Early Warning Score (NEWS), interleukin-6 (IL-6), and procalcitonin (PCT) for septicemia.

METHODS

Patients who underwent percutaneous nephrolithotomy were included in the study and divided into a control group and a septic shock group. The effectiveness of qSOFA, SIRS, NEWS, Interleukin-6, and Procalcitonin was assessed, with Receiver Operating Characteristic curves and Area Under the Curve used to compare the predictive accuracy of these four indicators.

RESULTS

Among the 401 patients, 16 cases (3.99%) developed septic shock. Females, elderly individuals, and patients with positive urine culture and positive nitrite in urine were found to be more susceptible to septic shock. PCT, IL-6, SIRS, NEWS, qSOFA, and surgical time were identified as independent risk factors for septic shock. The cutoff values are as follows: qSOFA score > 0.50, SIRS score > 2.50, NEWS score > 2.50, and IL-6 > 264.00 pg/ml. Among the 29 patients identified by IL-6 as having sepsis, 16 were confirmed to have developed sepsis. The qSOFA identified 63 septicemia cases, with 16 confirmed to have developed septicemia; NEWS identified 122 septicemia cases, of which 14 cases actually developed septicemia; SIRS identified 128 septicemia patients, with 16 confirmed to have developed septicemia. In terms of predictive ability, IL-6 (AUC 0.993, 95% CI 0.985 ~ 1) demonstrated a higher predictive accuracy compared to qSOFA (AUC 0.952, 95% CI 0.928 ~ 0.977), NEWS (AUC 0.824, 95% CI 0.720 ~ 0.929) and SIRS (AUC 0.928, 95% CI 0.888 ~ 0.969).

CONCLUSIONS

IL-6 has higher accuracy in predicting septic shock after PCNL compared to qSOFA, SIRS, and NEWS.

International Alliance of Urolithiasis (IAU) guideline on staghorn calculi management

BACKGROUND

The stone burden based management strategy reported in the guidelines published by different associations is well known for a long time. Staghorn calculi, representing the largest burden and most complex stones, is one of the most challenging cases to practicing urologists in clinical practice. The International Alliance of Urolithiasis (IAU) has released a series of guidelines on the management of urolithiasis.

PURPOSE

To develop a series of recommendations for the contemporary management management of staghorn calculi and to provide a clinical framework for urologists treating patients with these complex stones.

METHODS

A comprehensive literature search for articles published in English between 01/01/1976 and 31/12/2022 in the PubMed, OVID, Embase and Medline database is performed. A series of recommendations are developed and individually graded following the review of literature and panel discussion.

RESULTS

The definition, pathogenesis, pathophysiology, preoperative evaluation, intraoperative treatment strategies and procedural advice, early postoperative management, follow up and prevention of stone recurrence are summarized in the present document.

CONCLUSION

A series of recommendations regarding the management of staghorn calculi, along with related commentary and supporting documentation offered in the present guideline is intended to provide a clinical framework for the practicing urologists in the management of staghorn calculi.

Distribution and antimicrobial resistance patterns of urinary pathogens in preoperative midstream urine cultures from Chinese patients with urinary calculi: a meta-analysis

BACKGROUND AND OBJECTIVE

This study comprehensively evaluates the distribution patterns and antimicrobial resistance profiles of urinary pathogens in Preoperative midstream urine cultures collected from patients with urinary calculi in China over the last two decades.

METHODS

A cross-sectional analysis of 41 studies was conducted. A systematic search across various databases, including Wanfang Data, CNKI, SinoMed, Embase, PubMed, and Web of Science, was carried out, covering the time period from 2002 to 2022. Using R 4.2.1 software, a meta-analysis was performed to assess heterogeneity using Cochran's Q test and the I2 statistic.

RESULTS

In the analysis of preoperative midstream urine cultures from Chinese patients with urinary calculi, gram-negative bacteria dominated at 69%, with Escherichia coli (43%), Klebsiella pneumoniae (8%), Proteus mirabilis (6%), Pseudomonas aeruginosa (5%), Acinetobacter baumannii (3%), and Enterobacter cloacae (4%) being prominent. Gram-positive organisms included Enterococcus faecalis (9%), Enterococcus faecium (5%), and Staphylococcus aureus (4%). Over time, proportions of Proteus mirabilis, Enterococcus faecalis, and Staphylococcus aureus decreased, while Klebsiella pneumoniae and Pseudomonas aeruginosa increased. Notably, Escherichia coli proportion reduced from 37 to 33% within the last two decades. Antimicrobial resistance analysis indicated declining resistance in E. coli (e.g., co-trimoxazole from 73 to 55%, gentamicin from 64 to 40%), but rising resistance in piperacillin and cefotaxime (34-60%). Enterococcus faecalis exhibited increasing resistance to ampicillin (5-69%), gentamicin (59-94%), and tetracycline (77-89%) over time, while resistance to levofloxacin and ciprofloxacin notably decreased (72-16% and 49-8%, respectively).

CONCLUSION

Over the past two decades, the proportion of gram-negative bacteria was declined, while the proportion of gram-positive bacteria increased. Escherichia coli remained the most common pathogen in the urine culture of patients with urinary calculi in China and the resistance of Escherichia coli to commonly used antibiotics increased. Clinicians should select appropriate antibiotics according to the results of urine culture and drug sensitivity test to reduce the occurrence of antibiotic resistance.

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.

Feasibility of Simultaneous Bilateral Endoscopic Surgery in Prone Split-Leg Position for Bilateral Upper Urinary Tract Calculi: A Pilot Study

INTRODUCTION

We explored the viability of simultaneous bilateral endoscopic surgery (SBES) in the prone split-leg position for managing bilateral calculi.

METHODS

We retrospectively reviewed 72 patients who underwent SBES, with procedures involving ureteroscopy (URS) and contralateral percutaneous nephrolithotomy (PNL) simultaneously, in prone split-leg position.

RESULTS

Operative times averaged 109.38 ± 30.76 min, with an average hospital stay of 7.79 ± 3.78 days. The bilateral stone-free rate (SFR) was 70.83%, while URS and PNL demonstrated comparable unilateral SFR (83.33% and 79.17%, respectively). Receiver operating characteristics curves for predicting unilateral residual fragments yielded an area under the curve of 0.84 (URS) and 0.81 (PNL) with respective cutoff values of stone diameter of 11.55 mm and 23.52 mm. Fifty-seven (79.17%) and 15 (20.83%) patients encountered grade 0-1/2 complications, with no severe complications (grade 3-5) recorded. No significant changes in blood count or renal function were observed post-SBES.

CONCLUSIONS

SBES in the prone split-leg position is a viable option for managing bilateral upper tract urolithiasis. Larger scale studies are needed to further assess safety and efficacy in various positions.

Effect of preoperative prophylactic antibiotic use on postoperative infection after percutaneous nephrolithotomy in patients with negative urine culture: a single-center randomized controlled trial

PURPOSE

To compare the effects of different preoperative antibiotic prophylaxis (ABP) regimens on the incidence of sepsis after percutaneous nephrolithotomy (PCNL) in patients with negative urine culture.

METHODS

A single-center, randomized controlled trial (June 2022-December 2023) included 120 patients with negative preoperative urine cultures for upper urinary tract stones who underwent PCNL (chictr.org.cn; ChiCTR2200059047). The experimental group and the control group were respectively given different levofloxacin-based preoperative ABP regimes, including 3 days before surgery and no ABP before surgery. Both groups were given a dose of antibiotics before the operation. The primary outcome was differences in the incidence of postoperative sepsis.

RESULTS

A total of 120 subjects were included, including 60 patients in the experimental group and 60 patients in the control group. The baseline characteristics of the two groups were comparable and intraoperative characteristics also did not differ. The sepsis rate was not statistically different between the experimental and control groups (13.3% vs.13.3%, P = 1.0). A multivariate logistic regression analysis revealed that body mass index (BMI) (OR = 1.3; 95% CI = 1.1-1.6; P = 0.003) and operating time (OR = 1.1; 95% CI = 1.0-1.1; P = 0.012) were independent risk factors of sepsis.

CONCLUSION

Our study showed that prophylactic antibiotic administration for 3 days before surgery did not reduce the incidence of postoperative sepsis in patients with negative urine cultures undergoing PCNL. For this subset of patients, we recommend that a single dose of antibiotics be given prior to the commencement of surgery seems adequate.

The genetics of urinary microbiome, an exploration of the trigger in calcium oxalate stone

Background: Kidney stone disease is a global disease; however, it has not been totally understood. Calcium oxalate (CaOx) stone is the dominant type of kidney stone, and the potential factors involved in its formation are yet to be explored. Clinically, we found that the CaOx stones in patients were mainly unilateral; therefore, systemic factors cannot explain them, although some local factors must be involved. Urinary microbiota is involved in stone formation. Therefore, this study aimed to explore the association between the urinary microbiota and CaOx stones and provide insight into the medical treatment and prevention of CaOx stones. Methods: Sixteen pelvic urine samples were collected from the stone and non-stone sides of patients with unilateral CaOx stones following strict criteria. The 16S rRNA gene sequencing was performed on each pair of pelvic urine samples at the species level. Many bioinformatic analyses were conducted to explore the potential factors affecting CaOx stone formation. Results: Although no statistically significant difference was found between the overall microbiota of the pelvis urine from the two sides. Many biologically distinct taxa were observed, including many bacteria found in previous studies, like Proteobacteria, Actinobacteria, Firmicute and Enterobacter cloacae and so on. What's more, despite these common bacteria, our current study added to these bacterial communities with additional identification of Deinococcus-Thermus, Coriobacteriia, Porphyromonas and Ralstonia. To predict the functions of these microbiota, Kyoto Encyclopedia for Genes and Genomes and MetaCyc analysis were conducted and immunometabolism might be an important pathway. Moreover, a random forest predictor was constructed to distinguish the stone side from the non-stone side, with an accuracy of 62.5%. Conclusion: Our research profiled the microbiome in the pelvis urine from both the stone and non-stone sides of patients with unilateral CaOx stones, provided insight into the dominant role of urinary dysbiosis in CaOx stones formation. Furthermore, this study also predicted the potential crosstalk among urinary microbiota, immunometabolism, and CaOx stones.

The Mayo adhesive probability score predicts postoperative fever and intraoperative hemorrhage in mini-percutaneous nephrolithotomy

PURPOSE

Contemporary predictive tools for miniaturized percutaneous nephrolithotomy (mPCNL) mainly focus on stone clearance but not perioperative complications, especially infection and hemorrhage. This study aimed to evaluate whether the Mayo adhesive probability (MAP) score, an index of the perinephric fat characteristics, can predict postoperative fever and intraoperative hemorrhage in mPCNL.

METHODS

This is a retrospective study recruiting 159 mPCNL patients from July 2018 to January 2022. MAP scores were recorded using preoperative computed tomography. Postoperative complications included postoperative fever and intraoperative bleeding, defined as hemoglobin drop.

RESULTS

Over half patients had the MAP score ≧ 3. Men, elderly, chronic kidney disease, and diabetes were associated with a higher MAP score. The patients with a higher MAP score were more likely to have postoperative fever after mPCNL. On multivariate analysis, preoperative positive urine culture (OR 2.68) and a higher MAP score (OR 2.28) were both significantly associated with postoperative fever. ROC curves analysis of the combination of these two factors on predicting postoperative fever showed AUC values were 0.731 (0.652-0.810). Moreover, a higher MAP score (OR 2.30) and longer operative time (OR 2.16) were significantly associated with higher hemoglobin drop on multivariate analysis.

CONCLUSION

A high MAP score was associated with postoperative fever and intraoperative hemorrhage in patients undergoing mPCNL. The MAP score can be a novel and easy predictive tool to help endourologists improve the awareness of mPCNL safety.

Development and Validation of a Model to Predict Ureteral Stent Placement Following Ureteroscopy: Results From a Statewide Collaborative

OBJECTIVE

To develop and validate a model to predict whether patients undergoing ureteroscopy (URS) will receive a stent.

METHODS

Using registry data obtained from the Michigan Urological Surgery Improvement Collaborative Reducing Operative Complications from Kidney Stones initiative, we identified patients undergoing URS from 2016 to 2020. We used patients' age, sex, body mass index, size and location of the largest stone, current stent in place, history of any kidney stone procedure, procedure type, and acuity to fit a multivariable logistic regression model to a derivation cohort consisting of a random two-thirds of episodes. Model discrimination and calibration were evaluated in the validation cohort. A sensitivity analysis examined urologist variation using generalized mixed-effect models.

RESULTS

We identified 15,048 URS procedures, of which 11,471 (76%) had ureteral stents placed. Older age, male sex, larger stone size, the largest stone being in the ureteropelvic junction, no prior stone surgery, no stent in place, a planned procedure type of laser lithotripsy, and urgent procedure were associated with a higher risk of stent placement. The model achieved an area under the receiver operating characteristic curve of 0.69 (95% CI 0.67, 0.71). Incorporating urologist-level variation improved the area under the receiver operating characteristic curve to 0.83 (95% CI 0.82, 0.84).

CONCLUSION

Using a large clinical registry, we developed a multivariable regression model to predict ureteral stent placement following URS. Though well-calibrated, the model had modest discrimination due to heterogeneity in practice patterns in stent placement across urologists.

Dynamics of Urinary Extracellular DNA in Urosepsis

Extracellular DNA (ecDNA) is a promising candidate marker for the early diagnosis and monitoring of urinary tract infections (UTIs). The aim of our study is to describe the dynamics of ecDNA in the plasma and urine of patients with urosepsis as well as in a mouse model of UTI. Samples of blood and urine were collected from adult patients with UTIs and obstructive uropathy (n = 36) during the first 3 days at the hospital and during a follow-up. Bacterial burden and urinary ecDNA were evaluated in a mouse UTI model (n = 26) at baseline; 24, 48, and 72 h after UTI induction; and 7 days after UTI induction. The plasma ecDNA did not change during urosepsis, but the plasma DNase activity increased significantly at the follow-up. The urinary ecDNA decreased significantly during hospitalization and remained low until the follow-up (90% lower vs. admission). No change was seen in the urinary DNase activity. C-reactive protein (CRP) and procalcitonin are positively correlated with plasma and urinary ecDNA. A UTI caused sepsis in 23% of mice. The urinary ecDNA decreased by three-fold and remained low until day 7 post-infection. Urinary bacterial burden is correlated with urinary ecDNA. Urinary ecDNA is a potential non-invasive marker for monitoring the effects of treatment during urosepsis and is related to UTI progression in the experimental animal model.

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.

The role of microbiome: a novel insight into urolithiasis

Urolithiasis, referred to as the formation of stones in the urinary tract, is a common disease with growing prevalence and high recurrence rate worldwide. Although researchers have endeavoured to explore the mechanism of urinary stone formation for novel effective therapeutic and preventative measures, the exact aetiology and pathogenesis remain unclear. Propelled by sequencing technologies and culturomics, great advances have been made in understanding the pivotal contribution of the human microbiome to urolithiasis. Indeed, there are diverse and abundant microbes interacting with the host in the urinary tract, overturning the dogma that urinary system, and urine are sterile. The urinary microbiome of stone formers was clearly distinct from healthy individuals. Besides, dysbiosis of the intestinal microbiome appears to be involved in stone formation through the gut-kidney axis. Thus, the human microbiome has potential significant implications for the aetiology of urolithiasis, providing a novel insight into diagnostic, therapeutic, and prognostic strategies. Herein, we review and summarize the landmark microbiome studies in urolithiasis and identify therapeutic implications, challenges, and future perspectives in this rapidly evolving field. To conclude, a new front has opened with the evidence for a microbial role in stone formation, offering potential applications in the prevention, and treatment of urolithiasis.

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.

Can we identify the risk factors for SIRS/sepsis after percutaneous nephrolithotomy? A meta‑analysis and literature review

With the increase in percutaneous interventions such as percutaneous nephrolithotomy (PCNL) for renal lithiasis, infectious complications are becoming more frequent. The present study performed a systematic Medline and Embase databases search, using the following words: 'PCNL' [MeSH Terms] AND ['sepsis' (All Fields) OR 'PCNL' (All Fields)] AND ['septic shock' (All Fields)] AND ['urosepsis' (MeSH Terms) OR 'Systemic inflammatory response syndrome (SIRS)' (All Fields)]. Because of the technological advances in endourology, articles published between 2012 and 2022 were searched. Of the 1,403 results of the search, only 18 articles, representing 7,507 patients in which PCNL was performed, met the criteria to be included in the analysis. All authors applied antibiotic prophylaxis to all patients and, in some cases, the infection was treated preoperatively in those with positive urine cultures. According to the analysis of the present study, the operative time has been significantly longer in patients who developed SIRS/sepsis post-operatively (P=0.0001) with the highest heterogeneity (I²=91%) compared with other factors. Patients with a positive preoperative urine culture had a significantly higher risk of developing SIRS/sepsis following PCNL (P=0.00001), OD=2.92 (1.82, 4.68) and there was also a high degree of heterogeneity (I²=80%). Performing a multi-tract PCNL also increased the incidence of postoperative SIRS/sepsis (P=0.00001), OD=2.64 (1.78, 3.93) and the heterogeneity was a little smaller (I²=67%). Diabetes mellitus (P=0.004), OD=1.50 (1.14, 1.98), I²=27% and preoperative pyuria (P=0.002), OD=1.75 (1.23, 2.49), I²=20%, were other factors that significantly influenced postoperative evolution. A total of two factors analyzed, body mass index and patient's age, did not influence the outcome, P=0.45, I²=58% and P=0.98, I²=63%.

The Relationship between Preoperative Urine Culture and Post-Percutaneous Nephrostolithotomy Systemic Inflammatory Response Syndrome: A Single-Center Retrospective Study

BACKGROUND

To predict the occurrence of systemic inflammatory response syndrome (SIRS) after percutaneous nephrostrolithotomy(PCNL), preoperative urine culture is a popular method, but the debate about its predictive value is ongoing. In order to better evaluate the value of urine culture before percutaneous nephrolithotomy, we conducted a single-center retrospective study.

METHODS

A total of 273 patients who received PCNL in Shanghai Tenth People's Hospital from January 2018 to December 2020 were retrospectively evaluated. Urine culture results, bacterial profiles, and other clinical information were collected. The primary outcome observed was the occurrence of SIRS after PCNL. Univariate and multivariate logistic regression analysis was performed to determine the predictive factors of SIRS after PCNL. A nomogram was constructed using the predictive factors, and the receiver operating characteristic (ROC) curves and calibration plot were drawn.

RESULTS

Our results showed that there was a significant correlation between positive preoperative urine cultures and the occurrence of postoperative systemic inflammatory response syndrome. Meanwhile, diabetes, staghorn calculi, and operation time were also risk factors for postoperative systemic inflammatory response syndrome. Our results suggest that among the positive bacteria in urine culture before percutaneous nephrolithotomy, Enterococcus faecalis has become the dominant strain.

CONCLUSION

Urine culture is still an important method of preoperative evaluation. A comprehensive evaluation of multiple risk factors should be undertaken and heeded to before percutaneous nephrostrolithotomy. In addition, the impact of changes in bacterial drug resistance is also worthy of attention.

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.

Predictive values of the SOFA score and procalcitonin for septic shock after percutaneous nephrolithotomy

To investigate the value of combination of the Sequential Organ Failure Assessment (SOFA) score and procalcitonin (PCT) for prediction of septic shock after percutaneous nephrolithotomy (PCNL). A total of 1328 patients receiving PCNL for renal calculi were allocated into control group (without septic shock) and septic shock group, and related data were retrospectively collected. Univariate analysis was firstly performed, and the variables with two sided P < 0.10 were then included in logistic regression analysis to determine independent risk factors. Receiver operating characteristic (ROC) curve was utilized to evaluate the predictive values. Area under curve (AUC) was compared using Z test. Postoperative septic shock was developed in 61 patients (4.6%) and not developed in 1267 patients (95.3%). Multivariate analysis demonstrated that SOFA score (OR: 1.316, 95% CI 1.125–1.922), PCT (OR: 1.205, 95% CI 1.071–1.696) and operative time (OR: 1.108, 95% CI 1.032–1.441) were independent risk factors for septic shock with adjustment for sex, history of urolithiasis surgery, positive history of urine culture and history of PCNL. The ROC curves demonstrated that the AUCs of SOFA score and PCT for predicting septic shock after PCNL were 0.896 (95% CI 0.866–0.927) and 0.792 (95% CI 0.744–0.839), respectively. The AUC of their combination was 0.971 (95% CI 0.949–0.990), which was higher than those of individual predictions (vs 0.896, Z = 4.086, P < 0.001; vs 0.792, Z = 6.983, P < 0.001). Both the SOFA score and PCT could be applied in predicting septic shock after PCNL, and their combination could further elevate the diagnostic ability.

The renal pelvis urobiome in the unilateral kidney stone patients revealed by 2bRAD-M

Background

The pathogenesis of kidney stone disease (KSD) is not fully understood, and potential contributing factors remain to be explored. Several studies have revealed that the urinary microbiome (urobiome) of stone formers was distinct from that of healthy individuals using 16S rRNA gene sequencing, most of which only provided microbial identification at the genus level. 2bRAD sequencing for Microbiome (2bRAD-M) is a novel sequencing technique that enables accurate characterization of the low-biomass microbiome at the species resolution. We aimed to apply 2bRAD-M to profile the renal pelvis urobiome of unilateral kidney stone patients and compared the urobiome with and without stone(s).

Method

A total of 30 patients with unilateral stones were recruited, and their renal pelvis urine from both sides was collected. A ureteroscope was inserted into the renal pelvis with stone(s) and a ureteral catheter was placed into the ureteroscope to collect renal pelvis urine. This procedure was repeated again with new devices to collect the urine of the other side. 2bRAD-M was performed to characterize the renal pelvis urobiome of unilateral stone formers to explore whether microbial differences existed between the stone side and the non-stone side.

Results

The microbial community composition of the stone side was similar to that of the non-stone side. Paired comparison showed that Corynebacterium was increased and Prevotella and Lactobacillus were decreased in the stone side. Four species (Prevotella bivia, Lactobacillus iners, Corynebacterium aurimucosum, and Pseudomonas sp_286) were overrepresented in the non-stone side. 24 differential taxa were also identified between two groups by linear discriminant analysis effect size (LEfSe). Extensive and close connections among genera and species were observed in the correlation analysis. Moreover, a random forest classifier was constructed using specific enriched species, which can distinguish the stone side from the non-stone side with an accuracy of 71.2%.

Conclusion

This first 2bRAD-M microbiome survey gave an important hint towards the potential role of urinary dysbiosis in KSD and provided a better understanding of mechanism of stone formation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03639-6.

The Predictive Value of Preoperative Albumin–Globulin Ratio for Systemic Inflammatory Response Syndrome After Percutaneous Nephrolithotomy

Purpose

Methods

Results

Conclusion

The antibiotic strategies during percutaneous nephrolithotomy in China revealed the gap between the reality and the urological guidelines

Background

Correct perioperative antibiotic strategies are crucial to prevent postoperative infections during percutaneous nephrolithotomy (PCNL). We aimed to compare the realistic antibiotic strategies applied in China with current urological guidelines.

Methods

Between April and May 2020, urologists from China were invited to finish an online cross-sectional survey. The questionnaire was designed according to the current urological guidelines and literatures.

Results

3393 completed responses were received. 61.1% (2073/3393) respondents had urological experience of more than 10 years. 72.4% urologists chose multiple-dose antibiotics for patients with both negative urine culture (UC-) and negative urine microscopy (UM-) preoperatively. Respondents in central China (OR = 1.518; 95% CI 1.102–2.092; P = 0.011), east China (OR = 1.528; 95% CI 1.179–1.979; P = 0.001) and northeast China (OR = 1.904; 95% CI 1.298–2.792; P = 0.001) were more likely to prescribe multiple-dose antibiotic for UC-UM- patients. Notably, the respondents who finished PCNL exceeded 100 cases per year were in favor of single-dose administration (OR = 0.674; 95% CI 0.519–0.875; P = 0.003). There are only 8.3% urologists chose single-dose antibiotic for UC-UM+ patients, whereas 65.5% administered antibiotics for 1–3 days. Meanwhile, for UC+ patients, 59.0% of the urologists applied antibiotics shorter than 1 week, and only 26.3% of the urologists carried out routine re-examination of UC. Moreover, postoperative antibiotics were frequently prescribed for 3–6 days (1815; 53.5%). Finally, although 88.2% urologists considered stone culture important for management of postoperative antibiotics as the guideline recommended, only 18.5% performed it routinely.

Conclusions

The antibiotic strategies are different between current practice in China and the urological guidelines. The dissimilarities suggested that further studies should be conducted to investigate the reasons of the differences and standardize the application of antibiotics.

Efficacy of Flexible Ureteroscopic Lithotripsy and Percutaneous Nephrolithotomy in the Treatment of Complex Upper Urinary Tract Nephrolithiasis

Objective

A case-control study was conducted to compare the efficacy and prognostic factors of flexible ureteroscopic lithotripsy (FURL) and percutaneous nephrolithotomy (PCNL) when treating complex upper urinary tract renal calculi based on a retrospective cohort study.

Methods

The study period was from October 2019 to December 2021. A retrospective study was carried out on 100 patients with complicated upper urinary tract nephrolithiasis who underwent surgery in the Urology Department of our hospital. They were assigned into two groups: FURL and PCNL groups. The intraoperative blood loss, operation time, hematuria duration, hospital stay, primary stone removal rate, incidence of intraoperative and postoperative complications, VAS score, level of inflammatory factors, and micturition function were compared. According to the postoperative prognosis, the patients were reassigned into two groups: good prognosis group (n = 38) and poor prognosis group (n = 106). The factors related to poor prognosis after FURL and PCNL were screened, and multivariate loglistic regression analysis was adopted to determine the risk factors.

Results

The primary stone clearance rate in the PCNL group was significantly higher than that in the FURL group, and there was no significant difference in the incidence of intraoperative and postoperative complications between the two groups (P > 0.05). The intraoperative blood loss and the duration of hematuria in the PCNL group were significantly shorter than those in the FURL group, and the operation time and postoperative hospital stay in the FURL group were longer than those in the FURL group. The postoperative VAS score in the study group was significantly lower than that in the control group (P < 0.05). The levels of CRP, IL-1, TNF-α, and NF-κB in both groups decreased after operation, and the level of inflammatory factors in the PCNL group was significantly lower than that in the FURL group (P < 0.05). The indexes of IPSS and Q max in the PCNL group were significantly lower than those in the control group 3 months after operation. The index of micturition function in the PCNL group was significantly lower than that in the FURL group. Preoperative use of immunosuppressant, preoperative stone fever, positive preoperative urine culture, preoperative urinary leukocyte count ≥ 544 × L, intraoperative urinary opacity, and pus fur were significantly correlated with poor prognosis of ureteral patients (P < 0.05). Preoperative stone fever, high preoperative urinary leukocyte count, intraoperative urinary turbidity, and suppurative fur were independent risk factors for postoperative SIRS in patients with ureteral calculi.

Conclusion

PCNL is effective when treating complex upper urinary tract renal calculi. Compared with FURL, PCNL can remarkably reduce intraoperative blood loss and hematuria duration, can enhance micturition function, and will not remarkably increase the incidence of intraoperative and postoperative complications, high safety. High white blood cell count in urine before operation, fever due to stone before operation, turbid urine, and purulent fur during operation are independent risk factors for postoperative adverse outcome in patients with complex upper urinary tract renal calculi. Patients should be fully treated before surgery.

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.

16S rRNA gene sequencing reveals altered composition of gut microbiota in postoperative individuals with renal stones

Renal stones are a common urological disease with high prevalence and recurrence rates. Characterizing gut microbiome profiles of first‐onset renal calculi patients, both before and after surgery, may provide valuable insights and identify potential biomarkers for the disease. In this study, we explored the associations between the gut microbiome and renal stone formation using 16S ribosomal RNA (rRNA) gene sequencing. In brief, 20 patients were recruited, and information on health and eating habits within the previous 1–3 months was collected upon admission. A total of 493 operational taxonomic units (OTUs) were detected in 40 specimens, with an average of 67,888 ± 827 reads per sample. The results of OTU‐based partial least squares discriminant analysis (PLS‐DA) analysis showed differences between RS1 (fecal specimen before surgery) and RS2 (one month later after surgery) groups, with a significantly higher level of OTU7 in the RS2 group. Taxonomy‑based comparisons of the gut microbiome showed differences in the flora composition, with the prevalence of Enterobacteriales, Enterobacteriaceae, Gammaproteobacteria and Escherichia being higher in the RS2 group and the prevalence of Pseudomonadaceae, Pseudomonadales and Pseudomonas being higher in the RS1 group. Correlation analysis showed that an increased prevalence of Enterobacteriaceae, Gammaproteobacteria and Escherichia associated with a decreased level of urea, and a decreased creatinine level was correlated with an increased prevalence of Escherichia. These data strongly suggest that the gut microbiome plays an important role in kidney stone formation, and these findings may provide new insights for the prevention, diagnosis, and treatment of renal stones.

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.

Predictive accuracy of the modified SOFA score, SIRS criteria, and qSOFA score for uroseptic shock after mini-percutaneous nephrolithotomy

The purpose of this study was to determine the plausibility and utility of utilizing a modified SOFA (mSOFA) score for predicting uroseptic shock after mini-percutaneous nephrolithotomy. A cohort of 707 patients who received mini-PCNL from August 2019 to December 2020 was retrospectively evaluated. The area under receiver operating characteristic curve (AUROC) was used to compare the predictive value of septic shock between mSOFA, systemic inflammatory response syndrome (SIRS) and qSOFA. Among 707 patients, 24 patients experienced uroseptic shock after mini-PCNL. Compared with the no uroseptic shock group, the proportion of females and rates of preoperative urine culture, renal pelvis urine culture and stone culture positivity were higher in the uroseptic shock group, with high levels of preoperative C-reactive protein (CRP) and postoperative procalcitonin (PCT). In the uroseptic shock group, the mSOFA score increased by two or more points in 83.3%; 79.2% had at least two SIRS criteria, and 100% had a qSOFA score of at least one point. mSOFA score (AUROC = 0.866, 95% CI: 0.779-0.954) exhibited greater discrimination for uroseptic shock after PCNL than SIRS (AUROC = 0.838, 95% CI: 0.742-0.943) and qSOFA (AUROC = 0.851, 95% CI: 0.811-0.892). In conclusion, the predictive value of the modified SOFA score for uroseptic shock after mini-PCNL was greater than that of the qSOFA score or SIRS.

Development of a nomogram predicting the infection stones in kidney for better clinical management: A retrospective study

PURPOSE

To establish the first comprehensive nomogram for prediction of infection stones before treatment for better perioperative treatment and post-operative prevention of infection stones.

METHODS

A total number of 461 patients with kidney stones who underwent mini-percutaneous nephrolithotomy (mPCNL) and flexible ureteroscopy (FURS) between January 2019 to March 2021 were retrospectively analyzed. Univariable analysis and multivariable logistic regression analysis were conducted to identify the predictors for infection stones. Furthermore, the nomogram was established as a predicted model for infection stones.

RESULTS

Among 461 patients with infrared spectroscopy stone analysis, 100 (21.70%) had infection stones and 361 (78.31%) had noninfection stones. Multivariate logistic regression analysis indicated that female (OR 2.816, 95% CI 1.148-6.909, P = 0.024), recurrent kidney stones (OR 8.263, 95% CI 2.295-29.745, P = 0.001), stone burden (OR 6.872, 95% CI 2.973-15.885, P < 0.001), Hounsfield units (HU) (OR 15.208, 95% CI 6.635-34.860, P < 0.001), positive preoperative bladder urine culture (PBUC) (OR 4.899, 95% CI 1.911-12.560, P = 0.001), positive urine leukocyte esterase (ULE) (OR 3.144, 95% CI 1.114-8.870, P = 0.030), urine pH (OR 2.692, 95% CI 1.573-4.608, P < 0.001) and positive urine turbidity (OR 3.295, 95% CI 1.207-8.998, P = 0.020) were predictors for infection stone.

CONCLUSIONS

For patients with kidney stones, female, recurrent kidney stones, stone burden (>601 mm2), HU (750-1000), positive PBUC, positive ULE, urine pH and positive urine turbidity were predictors for infection stone. We established the first comprehensive model for identifying infection stones in vivo, which is extremely useful for the management of infection stones.

Predicting Sepsis in Patients with Ureteral Stones in the Emergency Department

BACKGROUND

In the absence of overt infectious signs, clinical criteria for early intervention in patients with ureteral stones are poorly defined. We aimed to develop a model that can identify patients who are at risk for developing sepsis if discharged home from the emergency department (ED).

MATERIALS AND METHODS

We retrospectively reviewed patients between January 2010 and December 2019 who were discharged from the ED after diagnosis of ureteral stones. The primary outcome was sepsis requiring urgent surgical decompression. We used multivariable logistic regression to identify predictors of sepsis. We refined the model using backwards stepwise regression with a threshold p-value 0.05.

RESULTS

We identified 1,331 patients who were discharged from the ED with ureteral stones. Of these patients, 22 (2%) subsequently developed sepsis requiring urgent decompression. In the initial multivariable model, female gender (OR 2.82, p=0.039) and urine white blood cells (WBC) (OR 1.02 per cell count, p<0.001) were predictive of sepsis. After performing backwards stepwise regression, female gender, urine WBC, and leukocytosis (WBC > 15,000/mm3) met criteria for inclusion in the model. A logistic model including these variables predicted sepsis with an internally cross-validated area under the curve of 0.79. Among patients with urine cultures completed in the ED, rates of sepsis were 9% in patients with positive cultures and 1% in patients with negative cultures (p<0.001). Antibiotic usage was not protective against developing sepsis.

CONCLUSIONS

Sepsis is a rare complication among patients with ureteral stones selected for conservative management. The presence of elevated urine WBC and female gender can help identify patients who are at risk of developing sepsis. Patients with risk factors should be managed with an increased index of suspicion for infection and may benefit from early intervention to reduce the risk of sepsis. Sepsis is more common in patients with positive urine cultures.

The role of quantitative gray-scale ultrasound histogram in the differential diagnosis of infected and non-infected hydronephrosis

BACKGROUND

The early detection of infected hydronephrosis is critical before lithotripsy. A feasible and noninvasive diagnostic method is of considerable clinical attention.

OBJECTIVES

This retrospective study was performed to find some quantitative evaluation parameters of B-mode Gray-scale ultrasound histogram analysis that might assist the early diagnosis of infected hydronephrosis and test their diagnostic efficacy.

MATERIALS AND METHODS

The ultrasound images and clinical data of 245 patients with hydronephrosis were retrospectively analyzed. Image J software was applied to obtain the gray-scale maps and the analysis results of the signal strength. The difference in the data between the infected and non-infected groups and the diagnostic value of the parameters were calculated.

RESULTS

In this retrospective study, 70 patients with infected hydronephrosis and 175 patients with non-infected hydronephrosis were enrolled. The echogenicity of internal effusion and the echogenicity ratio of infected cases were significantly higher than those of non-infected cases (p < 0.05). The cutoff values were 23.82 (AUC = 0.859) of echogenicity of internal effusion, while 0.27 (AUC = 0.832) of echogenicity ratio.

CONCLUSION

The quantitative evaluation of gray-scale ultrasound histogram is an objective and reliable method in differentiating infected from non-infected hydronephrosis.

Comparison of vacuum-assisted sheaths and normal sheaths in minimally invasive percutaneous nephrolithotomy: a systematic review and meta-analysis

BACKGROUND

A systematic review and meta-analysis was conducted to compare the safety and efficacy of vacuum-assisted sheaths and conventional sheaths in minimally invasive percutaneous nephrolithotomy (MPCNL) in the treatment of nephrolithiasis.

METHODS

PubMed, Web of Science, Embase, EBSCO, and Cochrane Library databases (updated March 2021) were used to search for studies assessing the effect of vacuum-assisted sheaths in patients who underwent MPCNL. The search strategy and study selection processes were implemented in accordance with the PRISMA statement.

RESULT

Three randomized controlled trials and two case-controlled trials that satisfied the inclusion criteria were enrolled in this meta-analysis. Overall, the stone-free rate (SFR) in patients who underwent vacuum-assisted sheaths was significantly higher than that in patients who underwent conventional sheaths (RR 1.23, 95% CI 1.04, 1.46, P = 0.02), with significant heterogeneity among the studies (I² = 72%, P = 0.03). In terms of the outcome of complications, vacuum-assisted sheath could bring a benefit to the postoperative infection rate (RR 0.48, 95% CI 0.33, 0.70, P < 0.00001) with insignificant heterogeneity among the studies (I² = 0%, P = 0.68). There was no significant difference in the blood transfusion rate (RR 0.35, 95% CI 0.07, 1.73, P = 0.17), with significant heterogeneity (I² = 66%, P = 0.35). Three studies contained operative time data, and the results indicated that the vacuum-assisted sheath led to a shorter operative time (MD = - 15.74; 95% CI - 1944, - 12.04, P < 0.00001) with insignificant heterogeneity (I² = 0%, P = 0.91).

CONCLUSION

The application of a vacuum-assisted sheath in MPCNL improves the safety and efficiency compared to the conventional sheath. A vacuum-assisted sheath significantly increases the SFR while reducing operative time and postoperative infection.

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.

Preoperative antibiotic therapy exceeding 7 days can minimize infectious complications after percutaneous nephrolithotomy in patients with positive urine culture

PURPOSE

To explore an appropriate duration of antibiotic therapy before percutaneous nephrolithotomy (PCNL) in patients with positive urine culture.

METHODS

From March 2016 to May 2018, consecutive patients with positive urine culture undergoing PCNL were prospectively registered. Initial preoperative antibiotics were given empirically. If needed, antibiotics were upgraded or adjusted to susceptible antibiotic after obtaining antibiotic-sensitivity test. Postoperative systemic inflammatory response syndrome (SIRS) was the primary outcome.

RESULTS

Among the 220 participants, the incidence of positive stone culture and SIRS were 85.5% and 36.8%. Escherichia coli (53.6%, 44.5%) and Proteus mirabilis (8.2%, 10.0%) were the top two bacteria in urine and stones. In univariable analysis, patients with postoperative SIRS had a higher rate of stone culture positivity (97.5% VS 78.4%, P < 0.001) and a shorter duration of preoperative antibiotics therapy (3.4 ± 2.7 days versus 4.2 ± 2.8 days, P = 0.037). The landscape of SIRS showed a declining trend as the elongation of preoperative antibiotics (P = 0.039). In a day-by-day comparison, SIRS was less prevalent in patients treated by pre-PCNL antibiotics ≥ 7 days than in those with antibiotics ≤ 6 days (21.7% VS 40.8%, P = 0.017). Multivariable logistic regression confirmed positive stone culture (P = 0.001, OR 11.115) as an independent risk factor and pre-PCNL antibiotics ≥ 7 days (P = 0.048, OR 0.449) as an independent protective factor for SIRS. Preoperative antibiotic ≥ 7 days decreased SIRS from 45.4 to 27.8% and from 9.1 to 0% in patients with a positive and negative stone culture, respectively.

CONCLUSION

Exceeding seven days should be appropriate duration of antibiotic therapy before PCNL in patients with positive urine cultures.

Preoperative Midstream Urine Cultures vs Renal Pelvic Urine Culture or Stone Culture in Predicting Systemic Inflammatory Response Syndrome and Urosepsis After Percutaneous Nephrolithotomy: A Systematic Review and Meta-Analysis

Purpose: To compare preoperative midstream urine cultures (PMUC) and renal pelvic urine culture (RPUC) or stone culture (SC) in predicting systemic inflammatory response syndrome (SIRS) and urosepsis after percutaneous nephrolithotomy (PCNL). Methods: We searched the PubMed, Web of Science, and EMBASE databases up to September 1, 2020, for relevant published studies. Two authors independently confirmed whether the literatures met the inclusion criteria and collected the data from the selected literatures. A meta-analysis was performed with Review Manager Software 5.4.1. A total of 14 studies with 3540 patients were selected and analyzed in the meta-analysis. Results: Pooled data showed that SC was associated with a higher sensitivity (odds ratios [OR] 2.36, confidence interval [95% CI] 1.31-4.25; p < 0.00001), positive predictive value (PPV) (OR 1.54, 95% CI 1.18-2.01; p = 0.16) and negative predictive values (OR 1.17, 95% CI 1.01-1.37; p = 0.06) in the diagnosis of SIRS and urosepsis after PCNL, and RPUC provided a significantly higher specificity (OR 2.70, 95% CI 2.16-3.38; p = 0.07) and PPV (OR 2.17, 95% CI 1.49-3.15; p = 0.48) than PMUC in the diagnosis of SIRS and urosepsis after PCNL. Conclusion: Intraoperative SC and RPUC are more reliable than PMUC in predicting postoperative SIRS and urosepsis, identifying causative organisms, and directing antibiotic therapy for patients who underwent PCNL. PMUC, SC, and RPUC should be routinely collected for the diagnosis and management of SIRS and urosepsis after PCNL.

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.

Escherichia coli Aggravates Calcium Oxalate Stone Formation via PPK1/Flagellin-Mediated Renal Oxidative Injury and Inflammation

Escherichia coli (E. coli) is closely associated with the formation of kidney stones. However, the role of E. coli in CaOx stone formation is not well understood. We explored whether E. coli facilitate CaOx stone formation and its mechanism. Stone and urine cultures were reviewed from kidney stone formers. The ability of calcium oxalate monohydrate (COM) aggregation was detected to evaluate the influence of uropathogenic E. coli, then gel electrophoresis and nanoLC-MS/MS to detect the crystal-adhered protein. Flagellin (Flic) and polyphosphate kinase 1 (PPK1) were screened out following detection of their role on crystal aggregation, oxidative injury, and inflammation of HK-2 cell in vitro. By transurethral injection of wild-type, Ppk1 mutant and Flic mutant strains of E. coli and intraperitoneally injected with glyoxylate in C57BL/6J female mice to establish an animal model. We found that E. coli was the most common bacterial species in patients with CaOx stone. It could enhance CaOx crystal aggregation both in vitro and in vivo. Flagellin was identified as the key molecules regulated by PPK1, and both of them could facilitate the crystal aggregation and mediated HK-2 cell oxidative injury and activated the inflammation-related NF-κB/P38 signaling pathway. Wild-type strain of E. coli injection significantly increased CaOx deposition and enhanced oxidative injury and inflammation-related protein expression, and this effect could be reversed by Ppk1 or Flic mutation. In conclusion, E. coli promotes CaOx stone formation via enhancing oxidative injury and inflammation regulated by the PPK1/flagellin, which activated NF-κB/P38 pathways, providing new potential drug targets for the renal CaOx calculus precaution and treatment.

Enhanced antibiotic treatment based on positive urine dipstick infection test before percutaneous nephrolithotomy did not prevent postoperative infection in patients with negative urine culture

INTRODUCTION

Urinary tract infection (UTI) should be treated before percutaneous nephrolithotomy (PCNL). However, the most appropriate treatment strategy in patients with negative urine culture but positive urine dipstick infection test (positive urinary leukocyte or nitrite reaction) remains unclear.

METHODS

From August 2016 to February 2018, 806 consecutive patients who had undergone the first-stage PCNL with negative urine culture were included. Preoperative urinalysis, antibiotic treatment, intraoperative stone culture, and postoperative systemic inflammatory response syndrome (SIRS) were prospectively recorded. The primary outcome was SIRS. The impact of preoperative antibiotics on preoperative urinary tract infection, stone culture, and postoperative SIRS was studied.

RESULTS

Among the 806 participants, the rate of positive urine dipstick infection test and SIRS were 26.8% and 7.2%, respectively. In univariable analysis, positive urinary nitrite (p<0.001), positive urinary leukocytes (p<0.001), positive urine dipstick infection test (p<0.001), longer duration of pre-PCNL antibiotics (p=0.001), higher level of pre-PCNL antibiotics (p=0.010), infection stones (p=0.001), and positive stone culture (p<0. 001) were risk factors for SIRS. However, multivariable analysis showed that positive stone culture (p=0.004) and prolonged preoperative treatment with antibiotics (p=0.021) were independent risk factors for SIRS. Although preoperative antibiotics reduced the incidence of positive urine leukocyte (p<0.001) or nitrite reactions (p<0.001), prolonged or upgraded preoperative antibiotics did not affect the incidence of positive stone culture. Whether stone culture was positive (p=0.023) or negative (p=0.025), prolonged preoperative treatment with antibiotics was associated with a higher incidence of SIRS.

CONCLUSIONS

Enhanced preoperative antibiotic treatment based on positive urine dipstick infection tests was insufficient to reduce the incidence of positive stone culture but increased the risk of SIRS after PCNL in patients with negative urine cultures.

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.

Antibiotic administration for negative midstream urine culture patients before percutaneous nephrolithotomy

To investigate how to administrate antibiotics for negative midstream urine culture (UC-) patients prior to percutaneous nephrolithotomy (PCNL), we retrospectively analyzed UC-patients receiving 0 or 3 days of cefuroxime prior to PCNL between July 2017 and May 2020. Patients were further divided into four groups (Group1A = urine with positive both nitrite and white blood cell (N + WBC +) and 0-day pre-operative cefuroxime; Group1B = N + WBC + and 3-day cefuroxime; Group2A = N - WBC + and 0-day cefuroxime; Group2B = N - WBC + and 3-day cefuroxime). All patients routinely received a dose of cefuroxime 30 min prior to the surgery. In addition, Group1B were matched to the Group1A; Group2B were matched to the Group2A at a 1:1 ratio regarding stone burden, the degree of hydronephrosis, stone hardness, age and sex in a sequential order. A total of 560 patients were included (Group1A = 72; Group1B = 72; Group2A = 208; Group2B = 208). The baseline characteristics were equally distributed between the matched-pair groups. Compared to Group1B, Group1A had a significantly higher incidence of SIRS, fever, urosepsis requiring only additional antibiotics, and an increased postoperative hospitalization stay. Compared to Group2B, Group2A had similar rate of infectious complications. In addition, Group1B was associated with a significantly lower rate of positive pelvic urine culture (PUC +) than that of Group1A; whereas, there was similar rate of PUC + between Group2A and Group2B. UC-patients with N + WBC + should be treated with extended period of antibiotic administration, and a single dose of prophylactic antibiotic was sufficient for UC-patients with N - WBC + prior to PCNL. Despite UC, it is suggested to stratify pre-operative antibiotics tailored to individual patients to optimize its application.

Comparison of contrast-enhanced ultrasound versus conventional ultrasound-guided percutaneous nephrolithotomy in patients with nondilated collecting system: a randomized controlled trial

OBJECTIVE

To compare the safety, effectiveness, and feasibility of contrast-enhanced ultrasound (CEUS) versus conventional ultrasound-guided percutaneous nephrolithotomy (PCNL) in patients with nondilated collecting system.

METHODS

Between July 2018 and July 2020, 160 kidney stone patients with nondilated collecting system planned for PCNL were randomly assigned into two groups, CEUS with retrograde ureteral contrast injection and conventional ultrasound with retrograde ureteral normal saline injection. Patient's demographics, the success rate of puncture, success rate of a single-needle puncture, number of punctures, puncture time, perioperative outcomes, stone-free rate, and incidence of complications were compared.

RESULTS

The success rate of a single-needle puncture for CEUS-guided PCNL was higher than that in the conventional ultrasound group (88.5% vs. 73.7%, p = 0.02). Patients performed with CEUS-guided PCNL required less needle passes (p = 0.02), shorter needle puncture time (p = 0.031), and shorter channel establishment time (p = 0.04) than those guided with conventional ultrasound. The postoperative hemoglobin decrease in the CEUS-guided PCNL group was less than that of the control group (p = 0.02). There was no significant difference in operating time, length of hospital stays, kidney function change, and complications between the two groups (p > 0.05). The 1-month stone-free rate was 94.9% in the CEUS group and 90.8% in the control group (p > 0.05).

CONCLUSIONS

Compared with conventional ultrasound, CEUS-guided PCNL may facilitate ultrasound-guided PCNL for patients without hydronephrosis, and benefited with a higher success rate of a single-needle puncture, less needle passes, shorter puncture time, and lower postoperative Hb drop.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR1800016981 KEY POINTS: • Compared with conventional ultrasound, CEUS-guided PCNL is a safe and efficacious procedure for kidney stone patients with nondilated collecting system. • Compared with conventional ultrasound, CEUS-guided PCNL benefited with a higher success rate of a single-needle puncture, less needle passes, shorter puncture time, and lower postoperative Hb drop. • CEUS-guided PCNL associated with the more accurate needle puncture and acceptable complications.