Predictors for uroseptic shock in patients who undergo minimally invasive percutaneous nephrolithotomy

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.

Postoperative SIRS after thermal ablation of HCC: Risk factors and short-term prognosis

Background

We aimed to explore the potential risk factors and short-term prognosis for SIRS after thermal ablation of hepatocellular carcinoma (HCC).

Methods

Data from patients with HCC who underwent thermal ablation in the Third Affiliated Hospital of Sun Yat-sen University between January 2015 and August 2021 were retrieved from the perioperative database. Pre-, intra- and postoperative data between SIRS group and non-SIRS group were compared and multivariate logistic regression analysis was performed to identify the risk factors for SIRS after thermal ablation.

Results

A total of 1491 patients were enrolled and 234 (15.7 %) patients developed SIRS after thermal ablation. Compared with those without SIRS, patients with SIRS had a longer hospital stay, higher hospitalization costs and higher risk of more severe postoperative complications. In the multivariate logistic regression analysis, current smoking (OR 1.58, 95 %CI 1.09-2.29), decreased HCT (OR 1.51,95 %CI 1.11-2.04), NEUT < 1.5 × 109/L(OR 1.74, 95 %CI 1.14-2.65), NEUT% < 0.5 or > 0.7 (OR 1.36, 95 %CI 1.01-1.83) and PT > 16.3s (OR 2.42, 95 %CI 1.57-3.74) were significantly associated with postoperative SIRS.

Conclusions

Current smoking, decreased HCT, neutropenia, abnormal percentage of neutrophils and prolonged PT are the independent risk factors for SIRS after thermal ablation of HCC, which worsens outcomes of patients. This study can help identify high-risk population and guide appropriate care so as to reduce the incidence of postoperative SIRS.

Optimizing stone harvesting in miniaturized-PCNL: a critical examination of renal access angles, technology, and the role they play in operative efficiency

PURPOSE

Stone retrieval can be a laborious aspect of percutaneous nephrolithotomy (PCNL). A unique phenomenon of mini-PCNL is the vortex-effect (VE), a hydrodynamic form of stone retrieval. Additionally, the vacuum-assisted sheath (VAS) was recently developed as a new tool for stone extraction. The purpose of our study is to investigate the impact of renal access angle (as a surrogate for patient positioning) on stone retrieval efficiency and compare the efficiency among methods of stone retrieval.

METHODS

A kidney model was filled with 3 mm artificial stones. Access to the mid-calyx was obtained using a 15Fr sheath. Stones were retrieved over three minutes at angles of 0°, 25°, and 75° utilizing the VE, VAS, and basket. Stones were weighed for comparison of stones/retraction and stones/minute. Trials were repeated three times at each angle.

RESULTS

Renal access angle of 0° was associated with increased stone retrieval for both the VE and VAS (p < 0.05). The VE was the most effective method for stones retrieved per individual retraction at an angle of 0° (p < 0.005), although when analyzed as stones retrieved per minute, the VE and VAS were no longer statistically different (p = 0.08). At 75°, none of the methods were statistically different, regardless if analyzed as stones per retraction or per minute (p = 0.20-0.40).

CONCLUSIONS

Renal access angle of 0° is more efficient for stone retrieval than a steep upward angle. There is no difference in stone retrieval efficiency between the VE and VAS methods, although both are superior to the basket at lower sheath angles.

International Alliance of Urolithiasis guideline on retrograde intrarenal surgery

OBJECTIVES

To set out the second in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis that concerns retrograde intrarenal surgery (RIRS), with the aim of providing a clinical framework for urologists performing RIRS.

MATERIALS AND METHODS

After a comprehensive search of RIRS-related literature published between 1 January 1964 and 1 October 2021 from the PubMed database, systematic review and assessment were performed to inform a series of recommendations, which were graded using modified GRADE methodology. Additionally, quality of evidence was classified using a modification of the Oxford Centre for Evidence-Based Medicine Levels of Evidence system. Finally, related comments were provided.

RESULTS

A total of 36 recommendations were developed and graded that covered the following topics: indications and contraindications; preoperative imaging; preoperative ureteric stenting; preoperative medications; peri-operative antibiotics; management of antithrombotic therapy; anaesthesia; patient positioning; equipment; lithotripsy; exit strategy; and complications.

CONCLUSION

The series of recommendations regarding RIRS, along with the related commentary and supporting documentation, offered here should help provide safe and effective performance of RIRS.

Reasons and risk factors for delayed discharge after day-surgery percutaneous nephrolithotomy

BACKGROUND

Day-surgery percutaneous nephrolithotomy (PCNL) is being developed quickly but some potential factors are affecting the recovery process. This study is aim to analyze the reasons and risk factors for delayed discharge after day-surgery PCNL.

METHODS

The data of 205 patients who accepted day-surgery PCNL in our institution between January 2018 and February 2020 were analyzed, retrospectively. Univariate and multivariate logistic regression analysis were used to analyze the risk factors for delayed discharge. Besides, the nomogram prediction model was established by the multivariable logistic regression analysis.

RESULTS

The rate of delayed discharge was 14.6%. Independent risk factors for delayed discharge were larger stone burden (odds ratio [OR] = 3.814, P = 0.046), positive urine nitrite (OR = 1.001, P = 0.030), longer duration of surgery (OR = 1.020, P = 0.044), multiple nephrostomy tubes (OR = 4.282, P = 0.008). The five main reasons that caused delayed discharge included psychological reasons, pain, bleeding, urosepsis, and urine leakage.

CONCLUSIONS

This study identified some independent risk factors for a hospital length of stay longer than 24 h. Patients with larger renal stones or positive urine nitrite may be at increased risk of delayed discharge after day-surgery PCNL. Reducing surgery time and nephrostomy tubes will help to facilitate recovery.

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.

A warning system for urolithiasis via retrograde intrarenal surgery using machine learning: an experimental study

Background

To develop a warning system that can prevent or minimize laser exposure resulting in kidney and ureter damage during retrograde intrarenal surgery (RIRS) for urolithiasis. Our study builds on the hypothesis that shock waves of different degrees are delivered to the hand of the surgeon depending on whether the laser hits the stone or tissue.

Methods

A surgical environment was simulated for RIRS by filling the body of a raw whole chicken with water and stones from the human body. We developed an acceleration measurement system that recorded the power signal data for a number of hours, yielding distinguishable characteristics among three different states (idle state, stones, and tissue–laser interface) by conducting fast Fourier transform (FFT) analysis. A discrete wavelet transform (DWT) was used for feature extraction, and a random forest classification algorithm was applied to classify the current state of the laser-tissue interface.

Results

The result of the FFT showed that the magnitude spectrum is different within the frequency range of < 2500 Hz, indicating that the different states are distinguishable. Each recorded signal was cut in only 0.5-s increments and transformed using the DWT. The transformed data were entered into a random forest classifier to train the model. The test result was only measured with the dataset that was isolated from the training dataset. The maximum average test accuracy was > 95%. The procedure was repeated with random signal dummy data, resulting in an average accuracy of 33.33% and proving that the proposed method caused no bias.

Conclusions

Our monitoring system receives the shockwave signals generated from the RIRS urolithiasis treatment procedure and generates the laser irradiance status by rapidly recognizing (in 0.5 s) the current laser exposure state with high accuracy (95%). We postulate that this can significantly minimize surgeon error during RIRS.

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.

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.

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

Objective

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

Methods

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

Results

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

Conclusion

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

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.

Value of preoperative urine white blood cell and nitrite in predicting postoperative infection following percutaneous nephrolithotomy: a meta-analysis

BACKGROUND

To evaluate to what degree preoperative urine white blood cell (WBC) and urine nitrite (NIT) values are predictive of postoperative infections following percutaneous nephrolithotomy (PCNL).

METHODS

A systematic literature search was performed of the PubMed, Embase, Cochrane Library, Wanfang Data, National Knowledge Infrastructure (CNKI), and China Science and Technology Journal Database (CSTJ or VIP) online databases to identify relevant studies that examined the predictive value of urine WBC or NIT as risk factors for post-PCNL infection, and the search was finished on February 28, 2020. Two independent reviewers screened the relevant studies, extracted necessary data from the eligible case-control studies (CCS), and assessed the quality of included studies through the Newcastle-Ottawa scale (NOS). RevMan 5.3 software and the Stata 16.0 software were used to complete the statistical analysis of data. Results are expressed as odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

According to the statistical analysis of 12 eligible studies involving 6113 patients, positive urine WBC (WBC+: OR =3.86, 95% CI: 3.03-4.91, P<0.001) and positive NIT (NIT+: OR =7.81, 95% CI: 5.44-11.21, P<0.001) in preoperative tests were identified as independent risk factors for postoperative infections following PCNL.

CONCLUSIONS

In summary, as risk factors for postoperative infections, the presence of preoperative urine WBC+ and NIT+ should be evaluated as part of clinical procedure, in order to reduce infections of PCNL.

Risk factors of infectious complications after retrograde intrarenal surgery: a retrospective clinical analysis

OBJECTIVE

Stone disease is one of the most common afflictions in modern society. Complications following retrograde intrarenal surgery (RIRS) vary considerably, and small-diameter ureteral access sheaths are reportedly significantly associated with rates of infectious complications following RIRS. This study aimed to explore additional risk factors for infectious complications after RIRS.

METHODS

This study retrospectively analyzed 602 patients who underwent RIRS between December 2016 and October 2019 at the First Affiliated Hospital of Fujian Medical University. All flexible ureteroscopic lithotripsy processes were conducted with patients under general anesthesia in the low lithotomy position. Postoperative systemic inflammatory response syndrome (SIRS) was diagnosed; statistical analyses comprised two-way analysis of variance (ANOVA) and one-way multivariate ANOVA.

RESULTS

The incidence of infectious complications after RIRS was 7.14%. Operative time was an independent risk factor that increased the risk of infection. Stone size >2 cm was observed in 153 (27.37%) patients in the SIRS group and 29 patients (67.44%) in the non-SIRS group.

CONCLUSIONS

Findings in the literature suggest that early antibiotic treatment and active fluid therapy might lower the rate of infectious complications after RIRS. Our results indicate that extended operative time and increased stone size may be risk factors for infectious complications after RIRS.

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.

Predictive factors of infectious complications in the postoperative of percutaneous nephrolithotomy

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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

OBJECTIVES

To obtain more accurate and rapid predictors of postoperative infections following percutaneous nephrolithotomy (PCNL) in patients with complex kidney stones, and provide evidence for early prevention and treatment of postoperative infections.

PATIENTS AND METHODS

A total of 802 patients with complex kidney stones who underwent PCNL, from September 2016 to September 2017, were recruited. Urine tests, urine cultures (UCs) and stone cultures (SCs) were performed, and the perioperative data were prospectively recorded.

RESULTS

In all, 19 (2.4%) patients developed postoperative urosepsis. A multivariate logistic regression analysis revealed that an operating time of ≥100 min, urine test results with both positive urine white blood cells (WBC+) and positive urine nitrite (WBC+NIT+), positive UCs (UC+), and positive SCs (SC+) were independent risk factors of urosepsis. The incidence of postoperative urosepsis was higher in patients with WBC+NIT+ (10%) or patients with both UC+ and SC+ (UC+SC+; 8.3%) than in patients with negative urine test results or negative cultures (P < 0.01). Preoperative WBC+NIT+ was predictive of UC+SC+, with an accuracy of >90%. The main pathogens found in kidney stones were Escherichia coli (44%), Proteus mirabilis (14%) and Staphylococcus (7.4%); whilst the main pathogens found in urine were E. coli (54%), Enterococcus (9.4%) and P. mirabilis (7.6%). The incidence of E. coli was more frequent in the group with urosepsis than in the group without urosepsis (P < 0.05).

CONCLUSIONS

WBC+NIT+ in preoperative urine tests could be considered as an early and rapid predictor of UC+SC+ and postoperative urosepsis. Urosepsis following PCNL was strongly associated with E. coli infections in patients with complex kidney stones.

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.