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

The mean Hounsfield unit range acquired from different slices produces superior predictive accuracy for pyonephrosis in obstructive uropathy

PURPOSE

To determine the non-contrast computer tomography imaging features of pyonephrosis and evaluate the predictive value of Hounsfield units (HUs) in different hydronephrotic region slices.

MATERIALS AND METHODS

We retrospectively reviewed data from patients with hydronephrosis who had renal-ureteral calculi. All patients were categorized into pyonephrosis and simple hydronephrosis groups. Baseline characteristics, the mean HU values in the maximal hydronephrotic region (uHU) slice, and the range of uHU in different slices (ΔuHU) were compared between the two groups. Univariate and multivariate analyses were performed to identify risk factors for pyonephrosis.

RESULTS

Among the 181 patients enrolled in the current study, 71 patients (39.2%) were diagnosed with pyonephrosis. The mean dilated pelvis surface areas were comparable between patients with pyonephrosis and simple hydronephrosis (822.61 mm² vs. 877.23 mm², p=0.722). Collecting system debris (p=0.022), a higher uHU (p=0.038), and a higher ΔuHU (p<0.001) were identified as independent risk factors for pyonephrosis based on multivariate analysis. The ΔuHU sensitivity and specificity were 88.7% and 86.4%, respectively, at a cutoff value of 6.56 (p<0.001), whereas the sensitivity and specificity for detecting pyonephrosis at a uHU cutoff value of 7.96 was 50.7% and 70.9%, respectively (p=0.003).

CONCLUSIONS

Non-contrast computer tomography was shown to accurately distinguish simple hydronephrosis from pyonephrosis in patients with obstructive uropathy. Evaluation of the ΔuHU in different slices may be more reliable than the uHU acquired from a single slice in predicting pyonephrosis.

Construction of an alignment diagram model for predicting calculous obstructive pyonephrosis before PNL

Background

To develop a model for the accurate prediction of calculous obstructive pyonephrosis prior to percutaneous nephrolithotomy (PNL), leading to early local anaesthesia microchannel nephrostomy for drainage of pyonephrosis.

Methods

By comparing the differences in baseline clinical indicators between the pyonephrosis group and nonpyonephrosis groups, independent risk factors were screened out, and a diagnostic alignment diagram model for predicting calculus obstructive pyonephrosis before PNL was established.

Results

Multivariate regression analysis showed that preoperative blood neutrophil count (Neu), serum creatinine level (Scr), serum albumin level (Alb), urine nitrite (UN), hydronephrosis density (HD) and fever history within one month (HFWOM) were independent risk factors for calculous obstructive pyonephrosis. The AUC value of the receiver operating characteristic (ROC) curve was 0.929. The calibration curves showed that the predictive model was well corrected and that the predictive model had strong consistency. Decision analysis curves showed good clinical efficacy of the model.

Conclusion

The alignment diagram model accurately predicts patients with preoperative calculous obstructive pyonephrosis in the PNL and provides an evidence-based basis for early renal microchannel nephrostomy.

Assessment of the incidence and risk factors of postoperative urosepsis in patients undergoing ureteroscopic lithotripsy

Introduction

Ureteroscopic lithotripsy (URSL) is an approved, minimally invasive, low-risk procedure for urolithiasis treatment. However, some patients may develop urinary tract infection (UTI) post-procedure, eventually leading to urosepsis. Determining the predictors of infection after URSL would help identify patients at a high risk of urosepsis, thereby enabling the early implementation of effective treatment. Therefore, we aimed to establish the incidence and predictors of urosepsis after URSL.

Material and methods

We assessed 231 patients who underwent URSL using a holmium laser. The incidence of urosepsis during the 30-day post-treatment period was analysed, and potential predictors of urosepsis, including patient characteristics and individual clinical factors, were examined.

Results

Statistical analysis revealed that 16.88% of patients had a confirmed positive urine culture before the procedure. Post-procedure urosepsis occurred in 4.76% of patients. Univariable analysis revealed that 3 factors were significantly associated with the risk of postoperative urosepsis: double-J stent insertion before URSL, pre-operative positive urine culture, and MDR pathogen found preoperatively. In multivariable analysis, only positive urine culture remained significantly associated with the risk of urosepsis after URSL.

Conclusions

Patients with positive urine culture before URSL are at significantly higher risk of urosepsis in the postoperative period. Hence, urine culture should be routinely performed before planned endoscopic urolithiasis treatment.

Risk factors of concurrent urinary sepsis in patients with diabetes mellitus comorbid with upper urinary tract calculi

BACKGROUND

Urinary sepsis is frequently seen in patients with diabetes mellitus (DM) complicated with upper urinary tract calculi (UUTCs). Currently, the known risk factors of urinary sepsis are not uniform.

AIM

To analyze the risk factors of concurrent urinary sepsis in patients with DM complicated with UUTCs by logistic regression.

METHODS

We retrospectively analyzed 384 patients with DM complicated with UUTCs treated in People's Hospital of Jincheng between February 2018 and May 2022. The patients were screened according to the inclusion and exclusion criteria, and 204 patients were enrolled. The patients were assigned to an occurrence group (n = 78) and a nonoccurrence group (n = 126). Logistic regression was adopted to analyze the risk factors for urinary sepsis, and a risk prediction model was established.

RESULTS

Gender, age, history of lumbago and abdominal pain, operation time, urine leukocytes (U-LEU) and urine glucose (U-GLU) were independent risk factors for patients with concurrent urinary sepsis (P < 0.05). Risk score = 0.794 × gender + 0.941 × age + 0.901 × history of lumbago and abdominal pain - 1.071 × operation time + 1.972 × U-LEU + 1.541 × U-GLU. The occurrence group had notably higher risk scores than the nonoccurrence group (P < 0.0001). The area under the curve of risk score for forecasting concurrent urinary sepsis in patients was 0.801, with specificity of 73.07%, sensitivity of 79.36% and Youden index of 52.44%.

CONCLUSION

Sex, age, history of lumbar and abdominal pain, operation time, ULEU and UGLU are independent risk factors for urogenic sepsis in diabetic patients with UUTC.

Percutaneous nephrolithotomy in patients with incidental encountered purulent urine at initial puncture

We are reporting the 39 patients' outcomes who underwent percutaneous nephrolithotomy and purulent urine encountered at the initial steps of surgery. Of 873 patients who underwent PCNL, 48 had purulent fluid during the initial puncture. After excluding those at risk for infection, we studied 39 patients' preoperative and postoperative variables-including postoperative day (POD) 1, 3, 5 fevers. In group 1, 21 patients had a nephrostomy tube placed, and PCNL was postponed. In group 2, 18 patients had successful stone removal in the first session. All surgeries were successful, with no septic events during follow-up. No significant differences in preoperative variables were found. 14% and 22% of patients in groups 1 and 2 had infected fluid (p = 0.470). Four patients in group 1 (19%) and seven patients in group 2 (38.9%) had a high fever (≥ 38 C) on POD1 (p = 0.171), and 1 (5%) in group 1 and 3 (17%) in group 2 had high fever on POD 3 (p = 0.22). No patients remained with high fever on POD5. Mild sepsis was diagnosed in 9.5% of group 1 and 16% of group 2 (p = 0.820), and hospitalization time differed significantly (p < 0.001). Stone size and operation time were correlated with postoperative fever, and prolonged hospital stays were associated with positive blood cultures and postponed procedures. PCNL with proper technique and antibiotics can lead to quicker recovery and reduced hospitalization time in selected patients with pus in their pelvicalyceal system.

Predicting the prognosis in patients with sepsis by a pyroptosis-related gene signature

Background

Sepsis remains a life-threatening disease with a high mortality rate that causes millions of deaths worldwide every year. Many studies have suggested that pyroptosis plays an important role in the development and progression of sepsis. However, the potential prognostic and diagnostic value of pyroptosis-related genes in sepsis remains unknown.

Methods

The GSE65682 and GSE95233 datasets were obtained from Gene Expression Omnibus (GEO) database and pyroptosis-related genes were obtained from previous literature and Molecular Signature Database. Univariate cox analysis and least absolute shrinkage and selection operator (LASSO) cox regression analysis were used to select prognostic differentially expressed pyroptosis-related genes and constructed a prognostic risk score. Functional analysis and immune infiltration analysis were used to investigate the biological characteristics and immune cell enrichment in sepsis patients who were classified as low- or high-risk based on their risk score. Then the correlation between pyroptosis-related genes and immune cells was analyzed and the diagnostic value of the selected genes was assessed using the receiver operating characteristic curve.

Results

A total of 16 pyroptosis-related differentially expressed genes were identified between sepsis patients and healthy individuals. A six-gene-based (GZMB, CHMP7, NLRP1, MYD88, ELANE, and AIM2) prognostic risk score was developed. Based on the risk score, sepsis patients were divided into low- and high-risk groups, and patients in the low-risk group had a better prognosis. Functional enrichment analysis found that NOD-like receptor signaling pathway, hematopoietic cell lineage, and other immune-related pathways were enriched. Immune infiltration analysis showed that some innate and adaptive immune cells were significantly different between low- and high-risk groups, and correlation analysis revealed that all six genes were significantly correlated with neutrophils. Four out of six genes (GZMB, CHMP7, NLRP1, and AIM2) also have potential diagnostic value in sepsis diagnosis.

Conclusion

We developed and validated a novel prognostic predictive risk score for sepsis based on six pyroptosis-related genes. Four out of the six genes also have potential diagnostic value in sepsis diagnosis.

Reported definitions of intraoperative hypotension in adults undergoing non-cardiac surgery under general anaesthesia: a review

Background

Intraoperative hypotension (IOH) during non-cardiac surgery is common and associated with major adverse kidney, neurological and cardiac events and even death. Given that IOH is a modifiable risk factor for the mitigation of postoperative complications, it is imperative to generate a precise definition for IOH to facilitate strategies for avoiding or treating its occurrence. Moreover, a universal and consensus definition of IOH may also facilitate the application of novel and emerging therapeutic interventions in treating IOH. We conducted a review to systematically record the reported definitions of intraoperative hypotension in adults undergoing non-cardiac surgery under general anaesthesia.

Methods

In accordance with Cochrane guidelines, we searched three online databases (OVID [Medline], Embase and Cochrane Library) for all studies published from 1 January 2000 to 6 September 2020. We evaluated the number of studies that reported the absolute or relative threshold values for defining blood pressure. Secondary aims included evaluation of the threshold values for defining IOH, the methodology for accounting for the severity of hypotension, whether the type of surgical procedure influenced the definition of IOH, and whether a study whose definition of IOH aligned with the Perioperative Quality Initiative-3 workgroup (POQI) consensus statement for defining was more likely to be associated with determining an adverse postoperative outcome.

Results

A total of 318 studies were included in the final qualitative synthesis. Most studies (n = 249; 78.3%) used an absolute threshold to define hypotension; 150 (60.5%) reported SBP, 117 (47.2%) reported MAP, and 12 (4.8%) reported diastolic blood pressure (DBP). 126 (39.6%) used a relative threshold to define hypotension. Of the included studies, 153 (48.1%) did not include any duration variable in their definition of hypotension. Among the selected 318 studies 148 (46.5%) studies defined IOH according to the POQI statement. When studies used a “relative blood pressure change” to define IOH, there was a weaker association in detecting adverse postoperative outcomes compared to studies who reported “absolute blood pressure change” (χ²(2) = 10.508, P = 0.005, Cramér’s V = 0.182). When studies used the POQI statement definition of hypotension or defined IOH by values higher than the POQI statement definition there were statistical differences observed between IOH and adverse postoperative outcomes (χ²(1) = 6.581, P = 0.037, Cramér’s V = 0.144). When both the duration of IOH or the numbers of hypotensive epochs were evaluated, we observed a significantly stronger relationship between the definition of IOH use the development of adverse postoperative outcomes. (χ²(1) = 4.860, P = 0.027, Cramér’s V = 0.124).

Conclusions

Most studies defined IOH by absolute or relative changes from baseline values. There are substantial inconsistencies in how IOH was reported. Further, definitions differed across different surgical specialities. Our findings further suggest that IOH should be defined using the absolute values stated in the POQI statement i.e., MAP < 60–70 mmHg or SBP < 100 mmHg. Finally, the number of hypotensive epochs or time-weighted duration of IOH should also be reported.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01605-9.

One-stage tubeless percutaneous nephrolithotomy for asymptomatic calculous pyonephrosis

Background

In recent years, the safety and effectiveness of one-stage percutaneous nephrolithotomy (PCNL) for the treatment of calculous pyonephrosis have been proven. In order to further reduce postoperative pain and hospital stay, we first proposed and practiced the idea of one-stage tubeless percutaneous nephrolithotomy for calculous pyonephrosis.

Methods

A retrospective analysis was performed of case data of 30 patients with asymptomatic calculous pyonephrosis treated in our center with one-stage PCNL from January 2016 to January 2021. Patients were routinely given 20 mg of furosemide and 10 mg of dexamethasone sodium phosphate injection intravenously at the beginning of anesthesia. Among them, 27 patients successfully underwent one-stage tubeless percutaneous nephrolithotomy, while 3 cases were given indwelling nephrostomy tubes because of proposed second-stage surgery or the number of channels was greater than or equal to 3. All patients were operated on by the same surgeon.

Results

Preoperatively, 11 of 30 patients (8 men and 22 women) had positive urine bacterial cultures, and all were given appropriate antibiotics based on drug sensitivity tests. All patients completed the surgery successfully. The mean operative time was 66.6 ± 34.7 min, the mean estimated blood loss was 16.67 ± 14.34 mL and the mean postoperative hospital stay was 5.0 ± 3.1 days. The mean postoperative hospital stay was 4.6 ± 2.5 days among the 27 patients with one-stage tubeless percutaneous nephrolithotomy. Of the 3 patients with postoperative fever, 2 had the tubeless technique applied. One patient with 3 channels was given renal artery interventional embolization for control of postoperative bleeding. None of the 30 patients included in the study developed sepsis. The final stone-free rate was 93.3% (28/30) on repeat computed tomography at 1 month postoperatively. The final stone-free rate was 92.6% in the 27 patients undergoing one-stage tubeless percutaneous nephrolithotomy (25/27).

Conclusions

One-stage tubeless PCNL is an available and safe option in carefully evaluated and selected calculous pyonephrosis patients.

A non-linear ensemble model-based surgical risk calculator for mixed data from multiple surgical fields

BACKGROUND

The misestimation of surgical risk is a serious threat to the lives of patients when implementing surgical risk calculator. Improving the accuracy of postoperative risk prediction has received much attention and many methods have been proposed to cope with this problem in the past decades. However, those linear approaches are inable to capture the non-linear interactions between risk factors, which have been proved to play an important role in the complex physiology of the human body, and thus may attenuate the performance of surgical risk calculators.

METHODS

In this paper, we presented a new surgical risk calculator based on a non-linear ensemble algorithm named Gradient Boosting Decision Tree (GBDT) model, and explored the corresponding pipeline to support it. In order to improve the practicability of our approach, we designed three different modes to deal with different data situations. Meanwhile, considering that one of the obstacles to clinical acceptance of surgical risk calculators was that the model was too complex to be used in practice, we reduced the number of input risk factors according to the importance of them in GBDT. In addition, we also built some baseline models and similar models to compare with our approach.

RESULTS

The data we used was three-year clinical data from Surgical Outcome Monitoring and Improvement Program (SOMIP) launched by the Hospital Authority of Hong Kong. In all experiments our approach shows excellent performance, among which the best result of area under curve (AUC), Hosmer-Lemeshow test ([Formula: see text]) and brier score (BS) can reach 0.902, 7.398 and 0.047 respectively. After feature reduction, the best result of AUC, [Formula: see text] and BS of our approach can still be maintained at 0.894, 7.638 and 0.060, respectively. In addition, we also performed multiple groups of comparative experiments. The results show that our approach has a stable advantage in each evaluation indicator.

CONCLUSIONS

The experimental results demonstrate that NL-SRC can not only improve the accuracy of predicting the surgical risk of patients, but also effectively capture important risk factors and their interactions. Meanwhile, it also has excellent performance on the mixed data from multiple surgical fields.

Risk factors for urosepsis in chronic kidney disease patients with urinary tract infections

Occurrence of urosepsis is not uncommon following urinary tract infections (UTI). However, there is a lack of evidence explaining the risk factors predisposing to urosepsis in patients with chronic kidney disease (CKD). This retrospective study was undertaken to evaluate the incidence and possible risk factors for urosepsis among patients hospitalized with UTI in a cohort of CKD patients. Patients were divided into the urosepsis group and the non-urosepsis group. Of 489 hospitalized patients with UTI, 70 (14.3%) acquired urosepsis. Stepwise multivariate logistic regression demonstrated that diabetes, urinary catheter and length of hospital stay (p < 0.001 for all) were significant independent predictive risk factors for urosepsis in CKD patients with UTI in addition to age, glomerular filtration rate, hydronephrosis, acute kidney injury and E. coli infection (p < 0.05 for all). Finally, Klebsiella spp. cases were associated with significantly higher odds for urosepsis than E. coli cases (OR: 3.5, 95% CI: 2.86-7.23, p < 0.001 vs. OR: 1.38, 95% CI: 1.19-3.69, p = 0.038). Diabetes, presence of an indwelling urinary catheter, length of hospitalization, and infection with Klebsiella spp were independent risk factors for urosepsis in CKD patients with UTI.

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.

Machine learning-assisted decision-support models to better predict patients with calculous pyonephrosis

Background

To develop a machine learning (ML)-assisted model capable of accurately identifying patients with calculous pyonephrosis before making treatment decisions by integrating multiple clinical characteristics.

Methods

We retrospectively collected data from patients with obstructed hydronephrosis who underwent retrograde ureteral stent insertion, percutaneous nephrostomy (PCN), or percutaneous nephrolithotomy (PCNL). The study cohort was divided into training and testing datasets in a 70:30 ratio for further analysis. We developed 5 ML-assisted models from 22 clinical features using logistic regression (LR), LR optimized by least absolute shrinkage and selection operator (Lasso) regularization (Lasso-LR), support vector machine (SVM), extreme gradient boosting (XGBoost), and random forest (RF). The area under the curve (AUC) was applied to determine the model with the highest discrimination. Decision curve analysis (DCA) was used to investigate the clinical net benefit associated with using the predictive models.

Results

A total of 322 patients were included, with 225 patients in the training dataset, and 97 patients in the testing dataset. The XGBoost model showed good discrimination with the AUC, accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 0.981, 0.991, 0.962, 1.000, 1.000, and 0.989, respectively, followed by SVM [AUC =0.985, 95% confidence interval (CI): 0.970–1.000], Lasso-LR (AUC =0.977, 95% CI: 0.958–0.996), LR (AUC =0.936, 95% CI: 0.905–0.968), and RF (AUC =0.920, 95% CI: 0.870–0.970). Validation of the model showed that SVM yielded the highest AUC (0.977, 95% CI: 0.952–1.000), followed by Lasso-LR (AUC =0.959, 95% CI: 0.921–0.997), XGBoost (AUC =0.958, 95% CI: 0.902–1.000), LR (AUC =0.932, 95% CI: 0.878–0.987), and RF (AUC =0.868, 95% CI: 0.779–0.958) in the testing dataset.

Conclusions

Our ML-based models had good discrimination in predicting patients with obstructed hydronephrosis at high risk of harboring pyonephrosis, and the use of these models may be greatly beneficial to urologists in treatment planning, patient selection, and decision-making.

Community Acquired Urosepsis: A surgical intensive care Experience

Urosepsis contributes significantly to the epidemiology of sepsis. Urosepsis can be classified as community acquired or hospital acquired, depending upon the origin of infection acquisition: either from the community or from a healthcare facility. A great deal of literature is available about nosocomial urosepsis, but the literature regarding community-acquired urosepsis (CAUs) is limited, and studies are underpowered. The aim of our study was to determine the epidemiology, bacteriology, severity, and outcome of CAUs. Methods and Patients: All patients admitted from the emergency department to the surgical intensive care unit (SICU) with urosepsis over a period of 10 years were identified and included retrospectively from the SICU registry. The study was retrospective. Data were entered into the SPSS program version 23, and groups were compared by using chi-square and t-tests. Results were considered statistically significant at p ≤ 0.05. Results: During the study period, 302 patients with CAUs were admitted to the SICU. The common etiology was obstructive uropathy (60%). The Local Arab population outnumbered the non-Arab population (164/54.3%), and there were equal numbers of patients of both genders. Diabetes mellitus and hypertension together were the common comorbidities. Seventy-five percent of patients had acute kidney injury (AKI). Thirty-eight percent of patients had percutaneous nephrostomy, and 24.8% of patients underwent endoscopic stent insertion to relieve the obstruction. Ninety-three percent of patients were admitted with septic shock, and 71.5% had bacteremia. The common bacteria (36.1%) was extended-spectrum beta-lactamase-(ESBL)-producing bacteria, with a predominance of Escherichia coli (31.5%). Fifty-four percent of patients required a change of antibiotics to carbapenem. Eighty-two percent of patients had acute respiratory distress syndrome (ARDS). Patients with bacteremia had a statistically significant AKI, ARDS, and septic shock (p < 0.001). Male patients had a significantly higher incidence of oliguria, intubation, and ARDS (p < 0.05). Eight patients died of urosepsis during the study period, giving a mortality rate of 2.6%. Conclusion: In our patients, obstruction of urine flow was the most common cause of CAUs. Our urosepsis patients had a higher bacteremia rate, which led to higher incidences of organ dysfunction and septic shock. ESBL bacteria were a frequent cause of urosepsis, requiring a change of the initial antibiotic to carbapenem. Male patients had a significantly higher rate of organ dysfunction. Mortality in our urosepsis patients was lower than mentioned in the literature.

Minimally invasive management of acute ureteral obstruction and severe infection caused by upper urinary tract calculi

PURPOSETo evaluate therapeutic efficacy of two minimally invasive surgical methods in managing acute ureteral obstruction and severe infection caused by upper urinary tract calculi (UUTC).PATIENTS AND METHODSData of 47 patients diagnosed with acute upper urinary tract obstruction and severe infection caused by ureteral calculus using X-ray CT between September 2014 and January 2019 were retrospectively analyzed. All patients were treated with immediate renal drainage and, after infection and ureteral obstruction were relieved, UUTC removal. Renal drainage was performed by ultrasound-guided percutaneous nephrostomy and retrograde ureteral catheterization was performed using cystoscopy. Kidney and ureteral stones were removed; renal function and the urinary tract were examined by X-ray during follow-up.RESULTSPercutaneous nephrostomy was performed in 29 patients in a critical condition including intolerance to surgery, high-grade hydronephrosis, or failure of retrograde ureteric stent placement. In other 18 patients diagnosed with small stones (≤10 mm) and low-grade hydronephrosis, indwelling double-J ureteral stents were temporally installed by a cystoscope. Acute infection and ureteral obstruction were relieved; white blood cell counts returned to normal values within 3 to 7 days after drainage in all patients. In the second-stage treatment, percutaneous nephrolithotomy (PCNL), ureteroscopic lithotripsy, extracorporeal shock wave lithotripsy and nephrectomy were performed in 24, 10, 8 and 5 patients, respectively. No patients developed severe complication after stone removal surgery. All patients were followed up for 3 months to 4.5 years. Renal function was significantly recovered; 17/29 (59%) patients with elevated serum creatinine returned to normal and serum creatinine in 12/29 (41%) patients improved significantly after drainage, with a pre-operation level of 285±169μM vs 203±91μM post-operation (P = 0.014). Five patients were lost during follow-up.CONCLUSIONThis study demonstrated an optimal approach for relieving upper urinary tract obstruction and acute infection in which percutaneous nephrostomy drainage is preferred for patients with severe pyonephrosis, large stones (>10 mm) with high-grade hydronephrosis, steinstrasse, or failure in retrograde ureteric stent placement, while retrograde ureteral catheterization using cystoscopy is suitable for patients diagnosed with small stones (≤10 mm) and low-grade hydronephrosis.