Does leaving residual fragments after percutaneous nephrolithotomy in patients with positive stone culture and/or renal pelvic urine culture increase the risk of infectious complications?

Clinical significance of stone culture during endourological procedures in predicting post-operative urinary sepsis: should it be a standard of care-evidence from a systematic review and meta-analysis from EAU section of Urolithiasis (EULIS)

PURPOSE

Urinary sepsis is the leading cause of mortality in the setting of endourological procedures for stone treatment such as URS and PCNL; renal stones themselves may be a source of infection. Aim of this study is to determine the diagnostic accuracy of stone cultures (SC) collected during URS and PCNL in predicting post-operative septic complications, compared to preoperative bladder urine culture (BUC).

METHODS

We performed a systematic review (SR) of literature according to the PRISMA guidelines; Literature quality was evaluated according to The Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-I) assessment tool. A univariate meta-analysis (MA) was used to estimate pooled log odds ratio of BUC and SC, respectively.

RESULTS

Overall, 14 studies including 3646 patients met the inclusion criteria. Eight studies reported data from PCNL only; three from URS only; three from both URS and PCNL. Stone cultures showed a higher sensitivity (0.52 vs 0.32) and higher positive predictive value (0.28 vs 0.21) in predicting post-operative sepsis, compared to bladder urine cultures. The pool-weighted logarithmic odd risk (LOR) for BUC was 2.30 (95% CI 1.51-3.49, p < 0.001); the LOR for stone cultures (SC) in predicting post-operative sepsis was 5.79 (95% CI 3.58-9.38, p < 0.001).

CONCLUSION

The evidence from this SR and MA suggests that intraoperative SC from stone fragments retrieved during endourological procedures are better predictors of the likelihood of occurrence of post-operative sepsis compared to pre-operative BUC. Therefore, SC should be a standard of care in patients undergoing endourological interventions.

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.

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.

Influence of preoperative urine culture and bacterial species on urogenital sepsis after ureteral flexible lithotripsy in patients with upper urinary tract stones

Objective

This retrospective study aims to identify risk factors for urogenic sepsis in patients with upper urinary tract stones following ureteral flexible lithotripsy (FURL). Additionally, we analyze the clinical characteristics of bacterial infections post-surgery.

Methods

A total of 759 patients who underwent FURL at the Urology Department of Zunyi Medical University were included. Univariate and multivariate Logistic regression analyses were conducted to identify independent risk factors for urogenic sepsis post-FURL. The distribution of bacteria based on preoperative urine cultures was also analyzed. Statistical analysis was performed using R4.2.2 software.

Results

Of the 759 patients, positive preoperative urine culture, urine nitrite positivity, urine white blood cell count (WBC) ≥ 200 cells/μL, residual stones, and neutrophil-to-lymphocyte ratio (NLR) were found to be independent risk factors for urogenic sepsis after FURL. Among the 164 patients with positive preoperative urine cultures, 32 developed urogenic sepsis post-surgery, with 68.75% having positive preoperative cultures. The leading pathogens causing postoperative urogenic sepsis were Escherichia coli (E. coli), Enterococcus faecium, Proteus mirabilis, and Klebsiella pneumoniae. The probabilities of progression to urogenic sepsis were as follows: E. coli 19% (n = 12), Enterococcus faecium 43% (n = 3), Proteus mirabilis 33.3% (n = 1), and Klebsiella pneumoniae 33.3% (n = 1). The ages of affected patients were 47.17 ± 13.2, 53.7, 41, and 79 years, respectively. Rates of comorbid diabetes were 36.4, 66.7, 50, 100%, with nitrite positivity rates at 72.7, 33.3, 50, 0%. Ten female patients were infected with E. coli, while patients infected with Klebsiella pneumoniae had an NLR of 7.62.

Conclusion

Positive preoperative urine culture, urine nitrite positivity, urine WBC ≥ 200 cells/μL, residual stones, and NLR are independent risk factors for urogenic sepsis after FURL. Escherichia coli is the predominant pathogen post-FURL, with notable female prevalence and nitrite-positive urine in infections. Enterococcus faecium infections are associated with diabetes.

Nomogram to predict the risk of adverse outcomes in patients with residual stones following percutaneous nephrolithotomy

PURPOSE

To investigate the risk factors associated with adverse outcomes in patients with residual stones after percutaneous nephrolithotomy (PCNL) and to establish a nomogram to predict the probability of adverse outcomes based on these risk factors.

METHODS

We conducted a retrospective review of 233 patients who underwent PCNL for upper urinary tract calculi and had postoperative residual stones. The patients were divided into two groups according to whether adverse outcomes occurred, and the risk factors for adverse outcomes were explored by univariate and multivariate analyses. Finally, we created a nomogram for predicting the risk of adverse outcomes in patients with residual stones after PCNL.

RESULTS

In this study, adverse outcomes occurred in 125 (53.6%) patients. Multivariate logistic regression analysis indicated that the independent risk factors for adverse outcomes were the diameter of the postoperative residual stones (P < 0.001), a positive urine culture (P = 0.022), and previous stone surgery (P = 0.004). The above independent risk factors were used as variables to construct the nomogram. The nomogram model was internally validated. The calculated concordance index was 0.772. The Hosmer-Lemeshow goodness-of-fit test was performed (P > 0.05). The area under the ROC curve of this model was 0.772.

CONCLUSIONS

Larger diameter of residual stones, positive urine culture, and previous stone surgery were significant predictors associated with adverse outcomes in patients with residual stones after PCNL. Our nomogram could help to assess the risk of adverse outcomes quickly and effectively in patients with residual stones after PCNL.

Preclinical Studies on the Safety and Toxicity of Photoditazine in the Antibacterial Photodynamic Therapy of Uropathogenic Bacteria

The 'dusting' technique of lithotripsy for the removal of infected urinary calculi and the wide use of drainage after endoscopic surgery may stimulate spreading of multidrug-resistant bacterial strains. Antibacterial photodynamic therapy (PDT) is one promising method for the elimination these strains. The purpose of our study was to evaluate alterations of renal pelvis morphology and renal function in laboratory animals after bactericidal regimens of PDT. Renal pelvises of pigs were filled with Photoditazine and then assessed either by examining the accumulation of Photoditazine in the urothelium or by illumination with a laser at a wavelength of 662 nm. A renal test and a complete blood count was performed to assess a negative effect of the treatment on health. Structural alterations of the kidney tissues were analyzed by histological examination. No photosensitizer fluorescence was detected in the urothelium of the pelvis. Histological study showed that PDT caused minor changes to the urothelium of the renal pelvis but did not affect the underlying connective tissue. No renal function abnormalities were found after PDT. Thus, the study indicates that antibacterial PDT is a safety technique that can complement common antibiotic therapy in the surgical treatment of urolithiasis.

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.

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

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

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

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

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.

Miniaturized percutaneous Nephrolithotomy without antibiotic prophylaxis: a single institution experience

PURPOSE

To assess the feasibility of sparing routine antibiotic prophylaxis in patients without preoperative urinary tract infection (UTI) undergoing a miniaturized percutaneous nephrolithotomy (mPCNL).

PATIENTS AND METHODS

A retrospective, monocentric study was conducted to evaluate the outcome of a modified perioperative antibiotic management strategy according to the principles of antibiotic stewardship (ABS). From December 2015 patients undergoing mPCNL for kidney stone with preoperative unremarkable urine culture no longer received an antibiotic prophylaxis (NoPAP). The NoPAP group was compared to mPCNL patients who received standard antibiotic prophylaxis (PAP) in the two years before. Analysis focused on postoperative complications. Logistic regression analysis was performed to identify potential risk factors.

RESULTS

Postoperative fever occurred in 8% of the NoPAP and 9% of the PAP patients (p = 0.764). Clavien 1-3 complications did not differ between groups with 33% in the NoPAP and 41% in the PAP (p = 0.511). No Clavien 4-5 complications were seen. A (partial) staghorn stone (HR 5.587; p = 0.019) and an infectious stone component (HR 6.313; p = 0.003) were identified as significant risk factors for postoperative fever. By sparing routine antibiotic prophylaxis the overall antibiotic usage was reduced from 100% (PAP) to 9% (NoPAP).

CONCLUSION

Patients with negative preoperative UC, a none-staghorn stone and no history of recurrent UTI or infectious stones may not need routine antibiotic prophylaxis prior to mPCNL. A prospective validation is warranted.

Residual Stone Fragments After Percutaneous Nephrolithotomy: Shockwave Lithotripsy vs Retrograde Intrarenal Surgery

Background: Despite technology incorporation to percutaneous nephrolithotomy (PCNL), residual stone fragments (RSFs) may still persist after PCNL and need to be addressed to avoid regrowth or ureteral obstruction. The objective of this study was to compare the outcomes of retrograde intrarenal surgery (RIRS) to extracorporeal shockwave lithotripsy (SWL) for treating patients with RSFs after a previous standard PCNL. Materials and Methods: Adult patients with RSF after a standard PCNL submitted to RIRS or SWL in our Institution from January 2017 to January 2020 were retrospectively studied. Stone-free rate (SFR) was evaluated on postoperative day (POD) 90 by noncontrast CT (NCCT) or ultrasound and kidney, ureter, and bladder radiograph (KUB) for each renal unit. Surgical complications based on Clavien-Dindo classification during the 90 days of follow-up were recorded. Sample size was calculated for a power of 80% and a significance level of 0.05, assuming SFR of 20% for SWL and 50% for RIRS. Results: Thirty-three patients treated by SWL were compared with 36 patients treated by RIRS. Hospitalization time was longer in the RIRS group (4.18 vs 12.33 hours, p = 0.001). SFR and success rate were lower in SWL than RIRS group (24.2% vs 58.3%, p = 0.007 and 30.3% vs 72.2%, p = 0.004, respectively), using POD 90 NCCT in 81.8% and ultrasound and KUB in 18.2% of the SWL group and using POD 90 NCCT in 100% of the RIRS group. Minor complications (Clavien-Dindo < III) occurred in 11 of 36 (30.6%) patients submitted to RIRS and in 2 of 33 (6.1%) patients submitted to SWL group (p = 0.025). Two patients (6.1%) of the SWL group had Clavien-Dindo IIIb complication owing to Steinstrasse and were submitted to ureteroscopy. Emergency room visits were similar between groups (6.1% vs 8.3%, p = 1.0). Conclusions: RIRS has better SFR, higher minor complications, and lower major complications than SWL for the treatment of RSFs after standard PCNL.

Is physical therapy effective following extracorporeal shockwave lithotripsy and retrograde intrarenal surgery: a meta-analysis and systematic review

Background

Physical therapy, including percussion, inversion, vibration and combinations, was clinically performed to improve the stone free rate (SFR) following lithotripsy procedures. However, physical therapy is not widely accepted in clinical practice owing to lack of high level evidence support and a standard protocol. The present meta-analysis aimed to evaluate the efficacy and safety of physical therapy in improving SFR following extracorporeal shockwave lithotripsy (ESWL) and retrograde intrarenal surgery (RIRS).

Methods

Systematic review of literature from PubMed, Scopus, Cochrane library and Embase was performed in March 2019. The efficacy and safety of physical therapy after ESWL and RIRS were assessed by meta-analysis of SFR and complication rate.

Results

A total of 8 prospective studies with 1065 patients were enrolled. When compared to non-intervention, physical therapy provided a higher SFR (OR:3.38, 95% CI: 2.45–4.66, p < 0.0001) at all time points (week 1, week 2 and month 1), while there was no significant difference in complications such as hematuria, lumbago, dizziness and urinary tract infection (OR: 0.84; 95%CI: 0.62–1.13; p = 0.237). In subgroup analysis of different stone locations, lower calyx stone (OR: 3.51; 95%CI: 2.21–5.55; p < 0.0001), upper ureter and renal pelvic stones (OR:2.79; 95%CI:1.62–4.81; p = 0.0002) had a higher SFR after physical therapy, while there was no significant improvement in SFR in upper and middle calyx stones. In subgroup analysis of different techniques, EPVL (external physical vibration lithecbole, OR:3.47; 95%CI:2.24–5.37; p < 0.0001) and PDI (percussion, diuresis and inversion, OR:3.24; 95%CI:2.01–5.21; p < 0.0001) were both effective in improving SFR when compared to non-intervention.

Conclusions

Physical therapy is effective in improving the SFR after ESWL and RIRS, especially for lower calyx stones, upper ureter and renal pelvic stones, while without significant side effects. External physical vibration lithecbole (EPVL) might provide a relative uniformed and repeatable protocol for clinical practice of physical therapy.

Trial registration

PROSPERO 2019 CRD42019130228.

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.