The Evaluation of Risk Factors for Postoperative Infectious Complications after Percutaneous Nephrolithotomy

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.

Development and validation of a predictive model for post-percutaneous nephrolithotomy urinary sepsis: a multicenter retrospective study

BACKGROUND

The objective of this retrospective, multicenter study was to analyze the factors associated with the development of urogenital sepsis after percutaneous nephrolithotomy (PCNL) and to establish a nomogram prediction model of urogenital sepsis after PCNL.

METHODS

A total of 2066 postoperative PCNL patients were included from three medical institutions: Zunyi Medical University Hospital, Beijing Jishuitan Hospital Guizhou Hospital, and Fenggang County People's Hospital. Clinical data of 1623 patients from the Department of Urology of Zunyi Medical University Hospital were randomized into a training cohort (Zunyi training cohort, N.=1139) and an internal validation cohort (Zunyi internal validation cohort, N.=484) using computer generated random numbers in a 7:3 ratio. Univariate and multivariate logistic regression analyses were performed on the compliance training cohort to identify risk factors for urogenital sepsis after PCNL and to develop a column line graph prediction model based on these risk factors. Finally, Zunyi internal validation cohort and two external validation cohorts (Guiyang external cohort, N.=306; Fenggang external cohort, N.=137) were used to validate the prognostic accuracy of the nomogram prediction model. R4.2.2 statistical software was used for all statistical data analyses.

RESULTS

Multifactorial logistic regression analysis of the Zuiyi training cohort (N.=1139) identified five independent risk factors associated with urogenital sepsis after PCNL, including urine culture positivity (odds ratio [OR]=5.29, P<0.001), urine nitrite positivity (OR=5.97, P<0.001), operation time ≥60 min (OR=4.4, P=0.0037), residual stone (OR=5.18, P<0.001), and size ≥30 mm (OR=3.22, P=0.0086). Nomogram were constructed based on these independent risk factors. The area under the curve (AUC) of the nomogram model was 0.907 in the in-progress sample and 0.948 after internal validation. The AUC of the model was 0.855 and 0.804 after external validation of the Guiyang external validation cohort and the Fenggang validation cohort, respectively, indicating good discrimination ability. The calibration curves of the nomogram showed good agreement, and the decision curve analysis demonstrated high clinical utility.

CONCLUSIONS

Based on the clinical independent risk factors such as positive urine culture, positive urine nitrite, operation time ≥60min, stone residue, stone size ≥30mm, nomogram prediction model of urogenital sepsis after PCNL was established, which can provide reference for urologists to develop preoperative evaluation and treatment strategies for patients with percutaneous nephrolithotomy.

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 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.

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

Purpose

Methods

Results

Conclusion

Open surgery versus percutaneous nephrolithotomy for management of staghorn calculi

BACKGROUND

For urologists, treating staghorn stones remains a difficult challenge. Various studies have evaluated the results of percutaneous nephrolithotomy (PCNL) and open surgery in different populations but these results were controversial. Here, we aimed to compare and evaluate the results of open surgery and PCNL in the treatment of staghorn stones.

METHODS

This retrospective descriptive study was performed to compare the results of open surgery and PCNL in the treatment of staghorn stones in 2013-2021. A total of 360 participants were studied among the population. Demographic data of patients including age, gender, and comorbidities were obtained. We assessed variables including type of stone, serum creatinine, degree of hydronephrosis, and urine culture before the operation. All participants in our study were informed of the two surgical alternatives.

RESULTS

The mean length of hospital stay in PCNL patients was 3.88 ± 1.76 and in open surgery patients was 5.858 ± 2.12 (P = 0.003). In 30 patients (13.9%) in the PCNL group and 27 patients (18.8%) in the open surgery group, bleeding necessitating blood transfusion was the only intraoperative complication. 309 patients (85%) had no residual stones at the time of discharge from the hospital, which was 81.9% (177 cases) in patients treated with PCNL and 91.6% (132 patients) in the open surgery group (P > 0.05).

CONCLUSION

Staghorn calculi can be managed effectively with open surgery or PCNL. Given the reduced postoperative complication rate and higher stone-free rate, we believe open surgery is better technique for complicated staghorn stones with a high burden.

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

Objective

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

Patients and Methods

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

Results

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

Conclusion

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

Application of Suctioning Ureteral Access Sheath during Flexible Ureteroscopy for Renal Stones Decreases the Risk of Postoperative Systemic Inflammatory Response Syndrome

Purpose

To clarify the efficiency and outcomes of suctioning ureteral access sheath (UAS) during flexible ureteroscopic lithotripsy (fURL) for the management of renal stones.

Methods

Between January 2017 and January 2019, a total of 444 patients with renal stones undergoing fURL were divided into suctioning UAS and nonsuctioning UAS groups. The outcomes of patients in both groups were compared using a matched-pair analysis (1 : 1 scenario). Furthermore, a directed acyclic graph (DAG) was drawn to guide the multivariate logistic regression model and analyze the protective effect of suctioning UAS on the incidence of postoperative systemic inflammatory response syndrome (SIRS).

Results

Before propensity score matching, significant differences were observed between the two groups in blood white cell counts, urine white cell counts, preoperative fever, preoperative indwelling stents, and laterality (P < 0.05). Eighty-one patients in the suctioning UAS group were successfully matched with 81 patients in the nonsuctioning group. The stone-free rate (SFR) on postoperative day 1 after fURL in the suctioning group was higher than that in the nonsuctioning group (86.4% vs. 71.6%; P=0.034), whereas it was comparable between the two groups 1 month after the surgery (88.9% vs. 82.7%; P=0.368). The incidence of postoperative fever or SIRS was lower in the suctioning group (fever: 3.70% vs. 14.8%; P=0.030; SIRS: 1.23% vs. 12.3%; P=0.012). However, the operative duration was similar in both groups (mean (SD)) (72.9 (28.1) min vs. 80.0 (29.5) min; P=0.121). The result of the multivariate logistic regression model guided by DAG revealed that the application of nonsuctioning UAS (odds ratio: 5.28 [1.38-35.07], P=0.034) during fURL was associated with postoperative SIRS.

Conclusions

The application of suctioning UAS during fURL was associated with higher SFR on day 1 after surgery and a lower incidence of postoperative fever or SIRS.

Postoperative infective complications following percutaneous nephrolithotomy

Introduction

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

Primary and Secondary

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

Settings and Design

This is an institution-based observational study.

Materials and Methods

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

Statistical Analysis Used

Data analysis was performed using SPSS version 22.0.

Results

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

Conclusions

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

Controlled Fragmentation of Urinary Stones as a Method of Preventing Inflammatory Infections in the Treatment of Urolithiasis (Experience in Successful Clinical Use)

The introduction of technologically advanced methods of lithotripsy into medical practice changes the nature of postoperative complications. Among them, the main complications are inflammatory infections. This largely determines the search for new, improved methods of stone fragmentation avoiding small stone fragments and dissemination of the pelvicalyceal system of the kidney with stone-associated infection. The authors have developed a method for controlled stone fragmentation using a continuous-wave diode laser with a hot-spot effect at the optical fiber end. The aim of the study was to evaluate the efficacy of controlled urinary stone fragmentation using a continuous-wave diode laser with a highly heated distal end of the optical fiber light guide as a method of preventing inflammatory infections in clinical practice.

Materials and Methods

We analyzed 1666 case histories of urolithiasis patients who underwent percutaneous nephrolithotripsy/ nephrolithoextraction and contact ureterolithotripsy/ureteroextraction, we also performed a prospective analysis of complications based on the Clavien-Dindo classification in 90 patients who underwent fine fragmentation of stones with various lithotripters: ultrasonic, pneumatic, and holmium laser. The method of controlled stone fragmentation by a diode laser with a hot-spot effect was tested on postoperative samples of 26 renal calculi. For the first time in clinical practice, this method was tested in the bladder cavity (n=10).

Results

In the percutaneous nephrolithotripsy group, postoperative infectious and inflammatory complications occurred in 34.1% of cases, in the percutaneous nephrolithoextraction group - in 24.6%, in the contact ureterolithotripsy group - in 7.8%, in the ureterolithoextraction group - in 2.5%. The analysis made it possible to identify factors promoting the development of infectious and inflammatory complications. For the first time in clinical practice, there were successfully performed ten operations of stone fragmentation using a continuous-wave diode laser with a hot-spot effect. Controlled coarse fragmentation of stones providing the possibility to reduce the number of infectious and inflammatory complications was performed in the bladder as a model for testing the method.

Conclusion

The method of laser-induced controlled coarse fragmentation of stones with a hot-spot effect, developed and tested in clinical practice, is promising for the prevention of infectious and inflammatory complications in patients with potentially infected stones since their fine fragmentation and, consequently, spread of stone-associated toxins and microflora within the urinary system is avoided.

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.

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.

Predictive factors and management of urinary tract infections after kidney transplantation: a retrospective cohort study

BACKGROUND

Urinary tract infection (UTI) is one of the most common infectious complications in kidney transplant recipients. The aims of our study were to identify possible predictive factors for UTI and advocate for the management of UTI after kidney transplantation (KT).

METHODS

Between January 2013 and December 2018, 182 adult patients with end-stage kidney disease who underwent KT were retrospectively analyzed. Patients who had urinary symptoms and positive urine culture were diagnosed with UTI. The types of urinary bacteria causing UTIs were also examined.

RESULTS

UTIs occurred in forty-one patients (25.1%), and the median time to UTI onset (UTI-free survival) after KT was 189 days. The Cox hazard regression analysis showed that the predictive factors for UTI onset were as follows: posttransplant urinary catheterization, including indwelling urinary catheterization and clean intermittent catheterization; a maximum bladder capacity before KT of less than 150 ml; and a low serum albumin level at 1 month after KT. The most common causative agent was Escherichia coli (56.6%), followed by Enterococcus spp. (15.6%) and Klebsiella spp.

CONCLUSIONS

Kidney transplant recipients with prolonged postoperative malnutrition, posttransplant voiding dysfunction and/or urinary storage disorder had an increased risk of UTI. Bladder function tests, such as uroflowmetry, postvoid residual urine tests, and urodynamic tests, were needed to predict UTI. For patients with malnutrition, care should be taken to ensure sufficient calorie intake. Kidney transplant recipients who develop UTI should be treated as complicated UTI patients.

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

Background

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

Methods

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

Results

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

Conclusions

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

Preoperative risk factors for complications of percutaneous nephrolithotomy

This study was conducted to evaluate preoperative risk factors for development of complications of percutaneous nephrolithotomy (PCNL). All consecutive patients aged ≥ 16 years who underwent PCNL during 2015 were retrospectively reviewed. Non-contrast CT (NCCT) was performed for all patients to evaluate stone complexity. The technique of PCNL was the same for all patients. Intra-operative and postoperative complications were recorded and classified based on modified Clavien system. The differences in preoperative data (patients, renal and stone characteristics including Guy's and STONE scores) between complicated and uncomplicated cases were compared using univariate and multivariate statistical analyses for detection of independent risk factors. The study included 1178 patients (61% were males). Mean age was 50 ± 12 years, and mean BMI was 30.7 ± 5.7 kg/m². Complicated group included 166 patients (14.1%). Independent risk factors on multivariate analysis were infected preoperative urine culture (RR: 2.098, P 0.001, 95%CI: 1.380-3.189), largest stones diameter 30 mm or more (RR: 2.481, P > 0.001, 95%CI: 1.697-3.627) and number of calyces affected by the stones (RR: 2.431, P 0.002, 95%CI: 1.400-4.222 for affection of two calyces and RR: 2.778, P 0.005, 95%CI: 1.357-5.684 for affection of three calyces). While two scoring systems (Guy's and STONE) were not predictive of complications after PCNL, preoperative risk factors were infected preoperative urine culture, distribution of the stones or stone branches in two or three calyceal groups and stone size 30 mm or more.

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

Background

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

Methods

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

Results

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

Conclusions

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

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

Objective

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

Results

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

Conclusions

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

The evaluation of early predictive factors for urosepsis in patients with negative preoperative urine culture following mini-percutaneous nephrolithotomy

PURPOSE

To identify early predictive factors for urosepsis secondary to mini-percutaneous nephrolithotomy (MPCNL) in patients with negative preoperative urine culture (UC).

METHODS

A total of 786 patients with baseline negative UC who underwent MPCNL between January 2017 and June 2019 were retrospectively analyzed. Urosepsis was defined according to the Sepsis-3 definition. Subsequently, perioperative potential risk factors were compared between non-urosepsis and urosepsis groups.

RESULTS

Despite negative UC in all patients, the rate of positive stone culture (SC) was 16.0%; the rate of pelvic urine culture (PUC) was 7.5%; 23 cases (2.9%) developed urosepsis after MPCNL. Univariate analysis showed that urosepsis was associated with the female gender, BMI, stone burden, diabetes mellitus and preoperative urine test. Multivariate logistic regression analysis suggested that urine test with positive nitrite and white blood cells and leukocyte esterase (N+WBC+LE+) (OR 17.51, 95% CI 6.75-45.38, P < 0.001) and operative time > 120 min (OR 3.53, 95% CI 1.41-8.85, P = 0.007) were independent risk factors for urosepsis. Additionally, receiver operating characteristic curve analysis of N+WBC+LE+ showed that the area under the curve was 0.785 for predicting the occurrence of urosepsis. Further analysis showed that N+WBC+LE+ provided an efficient prediction of SC+/PUC+ (SC+ or PUC+) with 61.7% sensitivity and 97.3% specificity.

CONCLUSIONS

In spite of the baseline negative preoperative UC, 2.9% of patients developed urosepsis after MPCNL. N+WBC+LE + was determined to be an early and efficient prediction of intraoperative bacterial status and urosepsis following MPCNL. Nevertheless, further studies are needed to confirm the results.

Reducing postoperative morbidity of mini-invasive percutaneous nephrolithotomy: Would it help if blood vessels are left unharmed during puncture? A CONSORT-prospective randomized trial

BACKGROUND

The aim of this study was to provide a randomized controlled trial comparing single B-mode ultrasound guidance and color doppler ultrasound guidance in minimally invasive percutaneous nephrolithotomy.

METHODS

Three hundred patients with renal calculus were prospectively randomly assigned into 2 groups. In group 1 (150 patients), minimally invasive percutaneous nephrolithotomy (m-PCNL) were managed with single B-mode ultrasound guidance; In group 2 (150 patients), m-PCNL were managed with color Doppler ultrasound guidance and a needle bracket in order to guide placement at a target location beneath the skin. The characteristics of patients, operation, complications and prognosis, including body temperature, urine culture, and hematologic tests after the operation were recorded and compared.

RESULTS

Our vessel-sparing technique showed a statistically significant decrease in hemoglobin drop, postoperative procalcitonin values, the frequency of postoperative fever, systemic inflammatory response syndrome, and urosepsis (P < .05).

CONCLUSION

Using color Doppler ultrasound in real time and a needle bracket to detect and avoid main renal blood vessels decreased incidences of hemorrhagic complications and postoperative infection.

Research progress of percutaneous nephrolithotomy

Percutaneous nephrolithotomy (PCNL) is generally accepted as the gold standard treatment for the treatment of large kidney stones (> 2 cm). For nearly 40 years, with the continuous progress of technology and the constant updating of ideas, PCNL has made great progress. In this review, we discuss the current research progress, recent advancement and hot spot of the whole process of PCNL including anesthesia, position, puncture, dilation, lithotripsy approaches, perfusate, tube placement, hospitalization time, drug, treatment of residual stones, prognosis judgment and operation evaluation by summarizing the related research in this article.

Laparoscopic pyelolithotomy as a monotherapy for the management of intermediate-sized renal pelvic stones

Introduction:

Renal calculi are one of the major reason leading to kidney failure or urinal obstructions. Percutaneous nephrolithotomy is considered as the major management option for intermediate to large renal pelvic stones. In the present study we compare Percutaneous nephrolithotomy vs laparoscopic pyelolithotomy procedures in the management of intermediate sized renal pelvic stones.

Methods:

The time duration of study was between July 2012 and Jan 2014, 20 patients with solitary intermediate sized renal pelvic stones were selected and randomly divided into two groups; group one included 10 patients who were treated by laparoscopic pyelolithotomy and group two included 10 patients who were treated by PCNL. The differences in procedure time, blood loss, stone clearance and duration of hospital stay between the two procedures were compared and analyzed.

Results:

There was no difference between the two groups regarding patient demographics and stone size. There was statistically significant difference between laparoscopic pyelolithotomy and PCNL regarding mean estimated blood loss (<50 mL vs. 180–250 mL), hospital stay (3–5 days vs. 4–6 days), mean time of postoperative analgesia (2.2 ± 0.9 days vs. 2 ± 0.9 days), and stone-free rate (100% vs. 95%). The operative time was significantly longer in the laparoscopic pyelolithotomy group (80–150 min vs. 45–75 min).

Conclusion:

Although PCNL is the gold standard for intermediate-sized renal pelvic stones of 2-4 cm, laparoscopic pyelolithotomy is a suitable surgical technique in selected cases.