Percutaneous nephrolithotomy for infection stones: what is the risk for postoperative sepsis? A retrospective cohort study

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.

Propensity Score-Matched Analysis of Perioperative Outcomes of Supine versus Prone Percutaneous Nephrolithotomy

Objective: To compare the perioperative outcomes of supine and prone percutaneous nephrolithotomy (PCNL). Methods: A retrospective search of a tertiary medical center database yielded 517 patients who underwent supine (n = 91) or prone (n = 426) PCNL between September 2015 and July 2020. Data on demographics, baseline clinical parameters, and stone burden were included as predictors in a logistic regression model, generating a set of propensity scores. Seventy patients after supine PCNL were propensity score-matched 1:1 with patients after prone PCNL and compared for operative time, perioperative complications, system complexity, and stone-free rate. Results: We found that the operative time was significantly shorter in the supine PCNL group than in the prone PCNL group (85.5 ± 25.2 min vs. 96.4 ± 25.8 min, respectively; p = 0.012). The majority of both groups had low-grade (I-II) complexity systems (85.6% and 88.6%, respectively), with no significant difference among all grade groups (p = 0.749). There were no significant differences between the supine and prone PCNL groups in terms of the overall perioperative complication rate (8.6% vs. 4.3%, respectively; p = 0.301) or stone-free rate (74.3 vs. 65.7%, respectively; p = 0.356), while the rate of blood transfusion was significantly higher in the supine group (p = 0.023). Conclusions: In our study, we used propensity score matching to compare patients who underwent PCNL in the supine or prone position, adjusting for selection bias. Supine PCNL was associated with a shorter operative time but a higher blood transfusion rate, with no differences in the overall complication and stone-free rates.

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.

Investigation of Virulence Genes of the Predominant Bacteria Associated with Renal Stones and their Correlation with Postoperative Septic Complications

Purpose

Nephrolithiasis is a worldwide disease, and 4.7% of the patients may develop postoperative sepsis. Characterization of virulence genes of bacteria associated with renal stones is still lacking in the literature. The study aimed to investigate the virulence genes of the predominant stone bacterial isolate and their association with postoperative septic complications in patients treated with percutaneous nephrolithotomy (PCNL).

Methods

Stone and midstream urine samples were collected from 200 nephrolithiasis patients who underwent PCNL. Microbiological examination and virulence profile were studied for the common bacteria isolated from the stones.

Results

Microbiological analysis revealed that Staphylococcus aureus was the predominant organism in stone samples (42.8%), while Escherichia coli (56.6%) was the dominant pathogen in midstream urine. Eight patients (4%) developed septic complications; stone culture was positive for S. aureus in seven and E. coli in one patient, while all but one had negative midstream urine. The patient with positive midstream urine culture had also S. aureus infection. Detection of virulence genes in S. aureus isolated from stones showed a high positivity of the hemolysine gene hla (93.3%) and adhesion gene fnbA (73.3%), whereas enterotoxin genes (sec and sea) were negative in all S. aureus stone cultures. Moreover, the adhesion genes (fnbB and can), hemolysine gene (hlb), panton-valentine leukocidin (pvl) gene and the enterotoxin gene (seb) were significantly higher in septic patients compared to the non-septic ones (p< 0.05). Interestingly, there was a significant relation between the existence of virulence genes and the resistance of antibiotics (p < 0.05).

Conclusion

There has been a notable shift toward gram-positive organisms (S. aureus) in the stone culture. Moreover, S. aureus virulence genes were significantly attributed to the resistance of some antibiotics and postoperative septic complications, suggesting that the stone culture could be more informative than urine culture, especially in predicting the risk of postoperative sepsis.

The effect of preoperative urine culture and bacterial species on infection after percutaneous nephrolithotomy for patients with upper urinary tract stones

To study the relationship between preoperative urine culture, bacterial species and infection after percutaneous nephrolithotomy in patients with upper urinary tract stones, and summarize the clinical characteristics of different bacterial infections. From January 2014 and January 2020, 963 patients with upper urinary tract stones who underwent PCNL in the department of urology of Fujian provincial hospital were included in the study. Information included the patient’s age, gender, weight, diabetes, chronic disease history, urine routine, preoperative urine culture results, stone size, number of stones, hydronephrosis level, operation time, body temperature, heart rate, blood pressure, breathing rate, hemoglobin, serum creatinine, bilirubin, platelets and whether there was preoperative infection were recorded. 141 patients (14.6%) had a positive urine culture before surgery, and 7 of them had multiple bacterial infections. The most common pathogenic bacteria was Escherichia coli, followed by Enterococcus and Klebsiella pneumoniae. A total of 74 cases (7.7%) of 963 patients with infection after PCNL occurred, 24 cases (32.4%) of infected patients progressed to urinary septic shock. Univariate analysis shown that the probability of infection in patients with long operation time and positive urine culture was significantly higher, and the difference was statistically significant. Further multivariate logistic regression analysis shown that positive urine culture before operation and long operation time were independent risk factors for infection after PCNL. Among the 29 patients with septic shock, 18 cases (62.1%) had a positive urine culture before surgery. The incidence (43.9%) of postoperative infection in Escherichia coli positive patients was significantly higher than that in the negative group, and the difference was statistically significant. The rate of patients with Escherichia coli infection progressing to septic shock was 9 cases (60%). 2 patients with Enterococcus faecium infection and 2 patients with Klebsiella pneumoniae infection all progressed to septic shock. The age of patients with post-PCNL infection caused by Escherichia Coli, Enterococcus faecium and Klebsiella pneumoniae were 58.53 ± 11.73 years, 76.5 years and 74 years.The body temperature of patients with post-PCNL infection caused by Escherichia Coli, Enterococcus faecium and Klebsiella pneumoniae were 39.10 ± 0.25 °C, 39.45 °C and 38.65 °C. The highest pct value of patients with post-PCNL infection caused by Escherichia Coli, Enterococcus faecium and Klebsiella pneumoniae were 80.62 ± 31.45 ng/mL, 24.32 ng/mL and 8.45 ng/mL. The nitrite positive rate of patients with post-PCNL infection caused by Escherichia Coli, Enterococcus faecium and Klebsiella pneumoniae were 64.51%, 16.6% and 0. Postoperative infection of PCNL is significantly correlated with positive preoperative urine culture, and positive preoperative urine culture is an independent risk factor for postoperative infection. The most common pathogen of postoperative infection of PCNL is Escherichia coli, followed by Enterococcus and Klebsiella pneumoniae. Patients with Escherichia coli infection are often positive for nitrite before surgery, mainly manifested by high fever, and PCT is significantly increased (often exceeded 100 ng/ml). Enterococcus faecium and Klebsiella pneumoniae infections mostly occur in elderly patients and often progress to septic shock. Patients with Enterococcus faecium infection have a high fever, and the PCT value is significantly higher (often exceeded 20 ng/ml). Patients with Klebsiella pneumoniae infection have a moderate fever, and the PCT value generally does not exceeded 10 ng/ml. Long operation time is another independent risk factor for PCNL infection.

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.

Case selection and implementation of tubeless percutaneous nephrolithotomy

Background

The tubeless percutaneous nephrolithotomy (PCNL) was proposed to eliminate the side effects of the nephrostomy tube in recent years, such as pain, channel infection, postoperative bleeding, and longer hospital stay. But there is neither clinical guidelines nor consensus about tubeless PCNL in clinical practice. The study is aimed to how to implement the tubeless PCNL step by step, including case selection preoperatively, improving the technique of the surgeon, making the correct decisions at the end of the procedure, which had not been previously examined.

Methods

From January 2017 to March 2018, 364 consecutive patients requiring PCNL were comprehensively analyzed preoperatively and patients were selected for scheduled tubeless PCNL based on four aspects. The selected patients were divided into two groups according to whether the nephrostomy tube was finally placed. The mean operative time, intraoperative blood loss, stone clearance rate, visual pain score, postoperative hospitalization days and perioperative complications were all evaluated.

Results

Based on the preoperative evaluation, 42 patients were selected for tubeless PCNL, among which there were finally 37 cases of completed tubeless PCNL. Compared with patients undergoing conventional PCNL, there were not statistical differences in the mean operative time (P=0.207) or intraoperative blood loss (P=0.450) in the tubeless group. Stone clearance rate was 100% in both groups. The visual pain scores in the tubeless PCNL group were lower on operation day (P=0.029), first postoperative day (P<0.001) and the day of discharge (P=0.025). The postoperative hospitalization for the tubeless PCNL group was shorter than that of the control group (P<0.001). No significant difference in grade 1 complications was seen (P=0.424), and no grade 2 or higher complications were observed in either group.

Conclusions

Postoperative pain was significantly relieved and postoperative hospitalization was significantly shortened in the tubeless PCNL group. Tubeless PCNL is safe if patients are carefully selected using four criteria before operation, attention is paid to four key points and five confirmations are made during operation.

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.

Massive retroperitoneal hematoma as an acute complication of retrograde intrarenal surgery: A case report

BACKGROUND

Retrograde intrarenal surgery (RIRS) has been proven to be a safe and effective treatment modality in large-scale quantitative studies. However, although its safety profile has been established, it also has a potential risk of life-threatening complications. We here describe our experience with a patient who developed a huge periureteral hematoma after RIRS with holmium laser lithotripsy.

CASE SUMMARY

A 73-year-old woman visited our center with a complaint of gross hematuria. An enhanced computed tomography (CT) scan revealed a 1.5-cm left renal pelvis stone with hydronephrosis. The patient underwent RIRS. During the surgery, a 12/14-Fr ureteral access sheath was applied and a 6-Fr ureteral catheter was indwelled thereafter. On postoperative day 1, she experienced aggravated left flank pain and left lower-quadrant tenderness without rebound tenderness. A follow-up CT scan was taken, which revealed a huge hematoma in the periureteral space, not in the perirenal space, with suspicious contrast medium extravasation. Immediate angiography was performed; however, it showed no evidence of active bleeding. She was conservatively managed with hydration and antibiotic and nonsteroidal anti-inflammatory drug therapy, and was discharged on postoperative day 7. However, she visited our outpatient department with recurrent left flank pain at 5 d from discharge. Ultrasonography confirmed that the double J-stent was intact. To rule out stent malfunction, the stent was changed. Decreased size of the hematoma was observed in the imaging studies, and conservative management for candiduria was performed for 1 wk.

CONCLUSION

Although RIRS is an effective and safe procedure for the management of renal stones, clinicians should be aware of its potential complications.

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

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

Renal pelvis urine Gram stain as a traditional, but new marker in predicting postoperative fever and stone culture positivity in percutaneous nephrolithotomy: an observational, prospective, non-randomized cohort study

PURPOSE

The aim of this study was to evaluate the diagnostic value of renal pelvis urine Gram staining (RPUGS) in predicting postoperative fever and renal stone culture (RSC) positivity in percutaneous nephrolithotomy (PCNL).

METHODS

Totally 141 consecutive patients undergoing PCNL for renal stone were included between January 2018 and December 2019. The RPUGS and renal pelvis urine culture (RPUC) were performed using urine sample from renal collecting system, while RSC was performed using stone fragments. Patients were divided into two groups as Group 1 (n = 119) without postoperative fever (< 38 °C) and Group 2 (n = 22) with postoperative fever (≥ 38 °C). Stone culture and Gram staining models were created for predicting postoperative fever using constant covariates of the presence of residual stone, hydronephrosis, and stone burden.

RESULTS

A significantly higher number of patients in Group 2 had RPUGS, RSC, and RPUC positivity (p < 0.001, for each). The sensitivity, specificity, positive predictive value, and negative predictive value of RPUGS in predicting postoperative fever were 72.7%, 89.9%, 57.1%, and 94.7%, respectively. It was observed that both models had similar predictive values and diagnostic performances. Although RSC and RPUGS had a similar diagnostic value in predicting postoperative fever in univariable analysis, both were found to be independent predictors in multivariable analysis (OR: 10.6, 95% CI 4.07-27.9, p < 0.001 and OR: 15.0, 95% CI 5.4-41.2, p < 0.001, respectively).

CONCLUSIONS

In conclusion, RPUGS is as effective as RSC in predicting fever after PCNL. We recommend RPUGS during PCNL to manage post-PCNL infectious complications.

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

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

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.

Risk factors and outcomes of urosepsis in patients with calculous pyonephrosis receiving surgical intervention: a single-center retrospective study

Background

Urosepsis is a catastrophic complication, which can easily develop into septic shock and lead to death if not diagnosed early and effectively treated in time. However, there is a lack of evidence on the risk factors and outcomes in calculous pyonephrosis patients. Therefore, this study was conducted to identify risk factors and outcomes of intra- and postoperative urosepsis in this particular population.

Methods

Clinical data of 287 patients with calculous pyonephrosis were collected. In the univariate and multivariate analysis, all patients were divided into urosepsis group and non-urosepsis group. The diagnosis of urosepsis was mainly on the basis of the criteria of American College of Chest Physicians (ACCP)/Society of Critical Care Medicine (SCCM). Patient characteristics and outcomes data were analyzed, and risk factors were assessed by binary logistic regression analysis.

Results

Of 287 patients, 41 (14.3%) acquired urosepsis. Univariate analysis showed that white blood cell (WBC > 10*10^9/L) before surgery (P = 0.027), surgery types (P = 0.009), hypotension during surgery (P < 0.001) and urgent surgery (P < 0.001) were associated with intra- and postoperative urosepsis for calculous pyonephrosis patients. In multivariate analysis, hypotension during surgery and urgent surgery were closely related to intra- and postoperative urosepsis. Outcome analysis suggested that patients developing urosepsis had a longer intensive care unit (ICU) stay and postoperative hospital stay and higher mortality.

Conclusions

Hypotension during surgery and urgent surgery were risk factors of intra- and postoperative urosepsis for calculous pyonephrosis patients, which may lead to a prolonged ICU stay, postoperative hospital stay and higher mortality.

Predicting the risk of sepsis and causative organisms following urinary stones removal using urinary versus stone and stent cultures

The association between foreign objects in the urinary system and urinary tract infections (UTI) is well established. The incidence of bacteriuria in patient with urinary catheters increases as dwelling time lengthens. The presence of ureteral stents and kidney stones is also associated with increased risk for bacteriuria and urinary tract infection. The aim of this study was to assess the bacterial characteristics of urine culture (UC) and foreign body culture (FBC), the concordance between them, and to identify risk factors for postoperative infections, in order to improve the treatment in these patients, using a prospectively collected database of patients who underwent ureteroscopy or percutaneous nephrolithotomy (PCNL) for the treatment of urinary stones between 2005 and 2016 at our institute. Preoperative UC was obtained from voided mid-stream urine for all patients. FBCs were obtained from ureteral stents removed and stones collected during the surgery. The cohort included 1011 patients. Mean age was 53 (SD 15.8), and 679 (67.2%) patients were male. Two hundred eighteen (21.6%) had a UTI in the year prior to the surgery. Among 795 patients who had sterile UC, 98 (12.3%) patients had positive FBC. Positive FBC was found in 53.7% of the patients with positive UC; however, FBC pathogens were similar to those identified in UC in 31% patients. The sensitivity of UC to detect FBC pathogens was 31.3%, and the PPV was 0.31. Urine cultures do not recognize all cases of pathogens colonizing foreign bodies in the urinary system. The colonization may be associated with an increased risk for SIRS. In more than one-quarter of the patients, the causative pathogen of sepsis is identified by FBC, but not by UC.

Efficacy of Intraoperative Renal Stone Culture in Predicting Postpercutaneous Nephrolithotomy Urosepsis/Systemic Inflammatory Response Syndrome: A Prospective Analytical Study with Review of Literature

AIM

To evaluate and study the efficacy of intraoperative renal stone culture (IOSC) in predicting postpercutaneous nephrolithotomy (PCNL) urosepsis (PPS) and systemic inflammatory response syndrome (SIRS). PPS is known to occur in patients despite negative preoperative midstream urine culture (MSUC).

METHODS

After obtaining institutional ethics committee approval and informed consent, 78 selected patients undergoing PCNL were evaluated as per protocol for risk factors for SIRS criteria with MSUC, intraoperative renal pelvic urine culture (RPUC), and IOSC.

RESULTS

MSUC was positive in six (7.7%) patients. The sensitivity, specificity, PPV, negative predictive value (NPV) and respiratory rate of MSUC for detecting SIRS were 20%, 93.15, 16.67%, 94.44%, and threefold, respectively. RPUC was positive in five (6.9%) patients with a specificity and NPV of 92.64% and 94.02%, respectively. IOSC positivity was seen in four (5.1%) patients with specificity and NPV of 94.5% and 3.2%, respectively. SIRS developed in five (6.4%) patients. MSUC, RPUC, and IOSC could not demonstrate any significant association with the occurrence of SIRS. Postoperative urine culture (POUC) was positive in 1/5 SIRS patients and no significant association (p < 0.182) could be demonstrated between the risk factors and PPS. Most complications were minor, while the mean hospital stay was significantly higher in SIRS patients.

CONCLUSIONS

While MSUC, RPUC, and IOSC were less sensitive in predicting the occurrence of SIRS/urosepsis in patients undergoing PCNL, nevertheless, we recommend routine IOSC for stone colonizing bacteria in at-risk select patients to predict potential PPS/SIRS. POUCs could be used in symptomatic SIRS to guide antimicrobial therapy in post-PCNL patients. Positive peri/intraoperative urine cultures may assist the urologist in directing appropriate antibiotics to prevent potential urosepsis in post-PCNL patients. Those with a higher blood transfusion rate and Clavien complications were at increased risk of PPS/SIRS. Escherichia coli was the most frequently isolated microbe followed by Klebsiella and Proteus, which were mostly sensitive to nitrofurantoin.

Percutaneous nephrolithotomy: complications and how to deal with them

Percutaneous nephrolithotomy is a common surgical treatment for large and complex stones within the intrarenal collecting system. A wide variety of complications can result from this procedure, including bleeding, injury to surrounding structures, infection, positioning-related injuries, thromboembolic disease, and even death. Knowledge of the different types of complications can be useful in order to prevent, diagnose, and treat these problems if they occur. This review describes the diversity of complications with the goal of improving their avoidance and treatment.

Urgent laparoscopic ureterolithotomy for proximal ureter stones accompanied with obstructive pyelonephritis: Is it safe and effective without preoperative drainage?

To evaluate the safety and efficacy of retroperitoneal laparoscopic ureterolithotomy (RLU) in the treatment of proximal ureteral stones accompanied with obstructive pyelonephritis without preoperative drainage.We retrospectively reviewed 21 cases of proximal ureteral stones with infected kidney undergoing RLU between July 2013 and September 2016. Stone-induced obstructive infected hydronephrosis was diagnosed using blood and urine tests and imaging modalities. Empirical effective broad spectrum antibiotic therapy was initiated immediately, and then urgent RLU was performed without preoperative drainage. During the surgical procedure, infected urine was also aspirated before stone was removed. Preoperative, intraoperative, and postoperative clinical data were collected.Operations were performed successfully without open conversion or blood transfusion. The mean operation time was 69.3 ± 12.33 minutes. For all the patients, the level of plasma procalcitonin decreased after RLU. The mean hospital stay duration was 6.4 ± 1.54 days. No septic shock or other severe complications occurred. By discharge, the body temperature and hemogram of each patient returned to normal. A 100% stone-free rate was achieved.Our study suggests that RLU is a potentially safe and effective method to treat proximal ureteral stones accompanied with obstructive pyelonephritis without any need of preoperative drainage.

Complications of retrograde intrarenal surgery classified by the modified Clavien grading system

The increase in the retrograde intrarenal surgery (RIRS) has been accompanied by the increase in complications. This study identified the factors that affected the severity of the complications using the modified Clavien classification system (MCCS). Three hundred and twenty-two consecutive RIRS performed by a single surgeon were analyzed. Data collection included demographics, clinical parameters, and perioperative and postoperative complications. The rate of adverse events for each of the Clavien grades was calculated, and statistical comparisons were made. The impact of each of the factors on the severity of the complications, based on the MCCS, was investigated using the univariate and multivariate analyses. The total complication rate was 26.1% (MCCS: I = 67.7%, II = 22.7%, IIIb = 7.2%, IVb = 2.4%). On the univariate analyses, the following factors affected complication: positive preoperative urine culture, operative time, irrigation rate, and stone burden. Multivariate logistic regression analysis demonstrated that positive preoperative urine culture, irrigation rate, and operative time were the significant factors affecting the complications. Most of the RIRS complications were in the lower Clavien grades and major complications were uncommon. Positive preoperative urine culture, irrigation rate, and operative time were the factors that affected complications.

Significance of preoperative neutrophil-lymphocyte count ratio on predicting postoperative sepsis after percutaneous nephrolithotomy

We evaluated the usefulness of preoperative neutrophil-lymphocyte count ratio (NLCR) in predicting postoperative sepsis after percutaneous nephrolithotomy (PCNL). In total, 487 patients who underwent PCNL for renal stones were included in the present retrospective study. The stone burden, number of tracts and location, operation time, fluoroscopy time, presence of residual stones, and blood transfusion rates were postoperatively recorded in all patients. All patients were followed up for signs of systemic inflammatory response syndrome (SIRS) and sepsis. The association of sepsis/SIRS with the risk factors of infectious complications, including NLCR, was evaluated. SIRS was detected in 91 (18.7%) patients, 25 (5.1%) of whom were diagnosed with sepsis. Stone burden, operation time, irrigation rate, previous surgery, nephrostomy time, access number, blood transfusion, residual stone, postoperative urinary culture, renal pelvis urinary culture, and stone culture were found to be predictive factors for SIRS and sepsis development. Receiver operating characteristic curve analysis revealed an NLCR cutoff of 2.50 for predicting the occurrence of SIRS/sepsis. We found that the incidence of sepsis was significantly higher in patients with NLCR ≥ 2.50 than in patients with NLCR < 2.50 (p = 0.006). Preoperative and postoperative urine culture positivity were associated with high NLCR (p = 0.039 and p = 0.003, respectively). We believe that preoperative NLCR may be a promising additive predictor of bacteremia and postoperative sepsis in patients who undergo PCNL for renal stones. This marker is simple, easily measured, and easy to use in daily practice without extra costs.