Ureteric stents vs percutaneous nephrostomy for initial urinary drainage in children with obstructive anuria and acute renal failure due to ureteric calculi: a prospective, randomised study

Meta-analysis of perioperative outcomes and safety of percutaneous nephrostomy versus retrograde ureteral stenting in the treatment of acute obstructive upper urinary tract infection

Background

The debate regarding the optimal drainage method for acute obstructive upper urinary tract infection persists, focusing on the choice between percutaneous nephrostomy (PCN) and retrograde ureteral stenting (RUS).

Aims

This study aims to systematically examine the perioperative outcomes and safety associated with PCN and RUS in treating acute obstructive upper urinary tract infections.

Methods

A comprehensive investigation was conducted using the Medline, Embase, Web of Science, and Cochrane databases up to December 2022, following the guidelines of the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. The utilized keywords included 'PCN', 'RUS', 'acute upper obstructive uropathy', and 'RCT'. Inclusion criteria encompassed studies providing accurate and analyzable data, which incorporated the total subject count, perioperative outcomes, and complication rates. The assessed perioperative outcomes included fluoroscopy time, normalization of temperature, normalization of serum creatinine, normalization of white blood cell (WBC) count, and operative time. Safety outcomes encompassed failure rate, intraoperative and postoperative hematuria, postoperative fever, postoperative pain, and postoperative nephrostomy tube or stent slippage rate. The study protocol was prospectively registered at PROSPERO (CRD42022352474).

Results

The meta-analysis encompassed 7 trials involving 727 patients, with 412 assigned to the PCN group and 315 to the RUS group. The outcome of the meta-analysis unveiled a reduced occurrence of postoperative hematuria in the PCN group [odds ratio (OR) = 0.54, 95% confidence interval (CI) 0.30-0.99, p = 0.04], along with a decreased frequency of insertion failure (OR = 0.42, 95% CI 0.21-0.81, p = 0.01). In addition, the RUS group exhibited a shorter fluoroscopy time than the PCN group (mean difference = 0.31, 95% CI 0.14-0.48, p = 0.0004).

Conclusion

Given the significant impact of hematuria and catheterization failure on postoperative quality of life, the preference for PCN appears more advantageous than RUS.

An atypical presentation of urolithiasis with pyonephrosis in a child: A case report

<b>Background:</b> Childhood urolithiasis is previously rare but increasingly recognized nowadays. Presentation varies, and often children, do not present with the classical symptoms commonly seen in adults.<br /> <b>Case report:</b> This case was initially presented to the emergency department with atypical symptoms of nephrolithiasis. Therefore, he was treated for acute appendicitis before an ultrasound abdomen revealed there is gross hydronephrosis, which is secondary to pelvic-ureteric junction obstruction. CT abdomen was then proceeded, found right nephrolithiasis and vesicoureteric calculus with right hydroureter and gross hydronephrosis. Retrograde pyelography (RPG), ureteroscopy (URS), and insertion of the stent for right pelvic-ureteric junction obstruction were performed and subsequently, he developed complications.<br /> <b>Conclusion: </b>The initial presentation of this case is common however not a classical presentation of renal stone. Therefore, evaluation of the symptoms and initial investigations should be done properly, so that we will not miss this common disease with the rare presentation, especially in children.

Primary versus deferred ureteroscopy for the management of obstructive anuria secondary to ureteric urolithiasis in children: a prospective randomized study

To compare the role of primary and deferred ureteroscopy (URS) in the management of obstructive anuria secondary to ureteric urolithiasis in pediatric patients. This prospective randomized study included 120 children aged ≤ 12 years who presented with obstructive anuria secondary to ureteric urolithiasis between March 2019 and January 2021. The children were subdivided into group A, which included children who had undergone primary URS without pre-stenting, and group B, which included children who had undergone URS after ureteric stenting. All children were clinically compensated and sepsis-free. Patients with underlying urological structural abnormalities were excluded. The operative time, improvement of renal functions, stone-free rate, and complications were compared between the two groups. At the 1-month follow-up, urine analysis; kidney, ureter, and bladder radiography; and ultrasonography were performed. The patient characteristics of both groups did not show any significant difference. Primary URS had failed in ten children (16.6%) in group A. Moreover, failure of stenting was noted in six patients (11%) in group B. The mean operative time for group B was significantly lower than that for group A (p ≤ 0.001). The stone-free rate was significantly higher in group B (p ≤ 0.001). The rate of overall complications was higher in group A. Deferred URS is preferable over primary URS in the management of obstructive anuria secondary to ureteric urolithiasis". In children because of the lower need for ureteric dilatation, higher stone- free rate, shorter procedure time, and lower complication rate.

Which is the best way for patients with ureteral obstruction? Percutaneous nephrostomy versus double J stenting

BACKGROUND

Percutaneous nephrostomy (PCN) and Double J stenting (DJS) are the 2 main treatment options of ureteral obstruction. We evaluate which of these 2 methods is superior concerning the course of procedure, postoperative complication and quality of life.

METHODS

A detailed review of electronic databases including PubMed, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure up to February 21st, 2021 was searched. Continuous data were evaluated using mean difference (MD) with 95% confidence interval (CI), while nominal data were analyzed by risk ratio (RR) with 95% CI. Meanwhile, we performed the subgroup analysis based on study design, disease type, sample size, sepsis, DJ diameter, nephrostomy diameter, anesthesia type and guidance under X-ray or ultrasound.

RESULTS

There were 18 previous studies included in current study. As a result, we found that there were significant differences in fluoroscopy time (MD = 0.31; 95% CI, 0.14-0.48, P < .001) and hospital stay (MD = 1.23; 95% CI, 0.60-1.85, P < .001). However, no statistic difference was detected in operative time (MD = 5.40; 95% CI, -1.78 to 12.58, P = .140) between the paired groups. Although DJS showed a higher rate of postoperative complications (25.19% vs 17.61%), there was no significant difference in the incidence of complications following DJS and PCN (RR = 0.92; 95% CI, 0.60-1.43; P = .720). Based on the EuroQol analysis, the 2 main treatment options had different impacts on quality of life. The pooled results showed that PCN patients reported more difficulties in self-care compared to DJS patients (RR = 3.07; 95% CI, 1.32-7.14; P = .009).

CONCLUSIONS

DJS is a safe and better method of temporary urinary diversion than PCN for management of ureteral obstruction with shorter fluoroscopy time and hospital stay. As for quality of life, patients receiving PCN had a distinct difficulty in self-care compared to those receiving DJS. However, these 2 treatment options often depends on the individual situation.

A novel method for estimating the urine drainage time from the renal collecting system

PURPOSE

Partial obstruction of the upper urinary tract is a common urological pathology that leads to progressive atrophy and dysfunction of the kidney. Most methods for evaluating the urine drainage rate, to assess the severity of partial obstruction, involve injection of markers into the blood stream and therefore the filtration rate from the blood effects the drainage rate. This study presents a novel method for assessing the drainage rate from the upper urinary tract by analyzing sequential fluoroscopic images from a routine nephrostogram, in which contrast material is introduced directly into the renal collecting system.

METHODS

Fluoroscopic images from 36 nephrostograms, following percutaneous nephrolithotomy, were retrospectively evaluated, 19 with a dilated renal pelvis. A radiological model for calculating the radiopacity of the renal pelvis, which reflects the amount of contrast material in each sequential image, was developed. Using this model, an algorithm was designed for generating a drainage curve and calculating the "drainage time" t_1/2 in which half of the contrast material has drained from the renal pelvis.

RESULTS

Analysis of images of a step-wedge phantom made of an increasing number of contrast material layers showed that the calculated radiopacity of each step was proportional to the amount of contrast material, independent of the background attenuation. Analysis of the nephrostograms showed that the drainage curves highly fitted an exponential function (R = 0.961), with a significantly higher t_1/2 for dilated cases.

CONCLUSION

The developed method may be used for a quantitative and accurate estimation of the urine drainage rate.

The impact of nephrostomy drainage prior to mini-percutaneous nephrolithotomy in patients with ESBL-positive Escherichia coli

OBJECTIVE

Extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) is one of the most frightening multidrug-resistant bacteria that usually causes sepsis. Herein we explored the benefits of nephrostomy drainage prior to percutaneous nephrolithotomy (PCNL) on infection outcomes in patients with ESBL-EC.

PATIENTS AND METHODS

Between June 2016 and April 2019, 43 consecutive patients with ESBL-EC who received nephrostomy drainage for > 24 h prior to PCNL were retrospectively evaluated as group 1. 86 patients were randomly selected from patients with ESBL-EC who received concurrent percutaneous access during PCNL as group 2. The postoperative infection complications were compared.

RESULTS

Although the total infection complications were not statistically different (11.6% vs. 25.6%, p = 0.066), the severity seemed to be worse among group 2 subjects. Severe infections, including urosepsis (4.7% vs.13.9%) and septic shock (2.3% vs 4.6%), were observed at twice or greater rates in group 2. Blood transfusions were also more frequent (2.3% vs. 13.9%, p = 0.039). Multivariate analysis demonstrated that preoperative drainage was an independent risk factor for postoperative infection events (OR 2.31 CI 1.14-3.48, p = 0.017). Subgroup analyses indicated that preoperative drainage may largely reduce the incidence of urosepsis in patients with hydronephrosis or without receiving preoperative carbapenem therapy.

CONCLUSION

Because of the high rate of severe infection after PCNL in patients with ESBL‑positive E. coli, preoperative nephrostomy drainage for > 24 h is an effective measure to reduce the risk of severe infection complications, especially in patients with hydronephrosis or those without preoperative carbapenem therapy.

Imaging modalities and treatment of paediatric upper tract urolithiasis: A systematic review and update on behalf of the EAU urolithiasis guidelines panel

BACKGROUND

Prompt diagnosis and treatment of paediatric urolithiasis are required to avoid long term sequelae of renal damage.

OBJECTIVE

To systematically review the literature regarding the diagnostic imaging modalities and treatment approaches for paediatric urolithiasis.

STUDY DESIGN

PubMed, Science Direct, Scopus and Web of Science were systematically searched from January 1980-January 2019. 76 full-text articles were included.

RESULTS

Ultrasound and Kidney-Ureter-Bladder radiography are the baseline diagnostic examinations. Non-contrast Computed Tomography (CT) is the second line choice with high sensitivity (97-100%) and specificity (96-100%). Magnetic Resonance Urography accounts only for 2% of pediatric stone imaging studies. Expectant management for single, asymptomatic lower pole renal stones is an acceptable initial approach, especially in patients with non-struvite, non-cystine stones<7 mm. Limited studies exist on medical expulsive therapy as off-label treatment. Extracorporeal shock wave lithotripsy (SWL) is the first-line treatment with overall stone free rates (SFRs) of 70-90%, retreatment rates 4-50% and complication rates up to 15%. Semi-rigid ureteroscopy is effective with SFRs of 81-98%, re-treatment rates of 6.3-10% and complication rates of 1.9-23%. Flexible ureteroscopy has shown SFRs of 76-100%, retreatment rates of 0-19% and complication rates of 0-28%. SFRs after first and second-look percutaneous nephrolithotomy (PNL) are 70.1-97.3% and 84.6-97.5%, respectively with an overall complication rate of 20%. Open surgery is seldom used, while laparoscopy is effective for stones refractory to SWL and PNL. Limited data exist for robot-assisted management.

CONCLUSIONS

In the initial assessment of paediatric urolithiasis, US is recommended as first imaging modality, while non-contrast CT is the second option. SWL is recommended as first line treatment for renal stones <20 mm and for ureteral stones<10 mm. Ureteroscopy is a feasible alternative both for ureteral stones not amenable to SWL as well as for renal stones <20 mm (using flexible). PNL is recommended for renal stones >20 mm.

Nephrolithiasis: Approach to Diagnosis and Management

Although kidney stones are less common in children than in adults, incidence in children is rising. Kidney stones may lead to significant morbidity in addition to escalating medical costs. Clinical presentation is variable. Bilateral kidney stones in a younger child should prompt work-up for primary hyperoxaluria. Metabolic abnormalities are more frequent in children and can result in frequent stone recurrence. Whole exome sequencing data shows genetic defects in about 30% of stone formers. 24 h urine collection should be conducted when patient receives his usual diet and fluid intake with normal activity. Infrared spectroscopy and X-ray diffraction are used for stone analysis. Urine studies should be delayed by 4-6 wk after stone fragmentation or treatment of any stone related complications. The goal of evaluation is to identify modifiable risk factors for which targeted therapy may be instituted. Primary indications for surgical intervention include pain, infection and obstruction. Extracorporeal shockwave lithotripsy (ESWL), ureteroscopy, and percutaneous nephrolithotomy (PCNL) are most commonly used, and selection is based on stone size, anatomy, composition and anatomy. Advances in technology have allowed a shift to minimally invasive surgeries. Comprehensive management requires multidisciplinary team. Children with kidney stones require long term follow-up with periodic assessment of stone forming activity and ascertaining stone burden. High index of suspicion should be there to diagnose diseases like primary hyperoxaluria, Dent's disease, renal tubular acidosis (RTA) etc. as these diseases have ramifications on kidney function and growth.

ACR Appropriateness Criteria® Radiologic Management of Urinary Tract Obstruction

Acute obstructive uropathy is a medical emergency, which often is accompanied by acute renal failure or sepsis. Treatment options to resolve the acute obstructive process include conservative medical management, retrograde ureteral stenting, or placement of percutaneous nephrostomy or nephroureteral catheters. It is important to understand the various treatment options in differing clinical scenarios in order to guide appropriate consultation. Prompt attention to the underlying obstructive process is often imperative to avoid further deterioration of the patient's clinical status. A summary of the data and most up-to-date clinical trials regarding treatment options for urinary tract obstruction is outlined in this publication. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Challenges in the diagnosis of severe renal trauma in child: A case report and literature review

INTRODUCTION

To report the management and outcome of one case of pediatric patient sustaining high-grade blunt renal trauma. We present and discuss the clinical characteristics and radiologic features of the patient.

PATIENTS AND METHODS

A 10 years old child was admitted for serious blunt renal trauma formed a huge urinoma in the right renal after injury gradually in 2018. We treated the patient with synchronous percutaneous nephrostomy drainage and retrograde ureteral catheterization. A retrospective review was performed of this case, including the clinical features, imaging studies and short-term follow-up. A literature review was also performed to highlight the principals of diagnosis and treatment of severe blunt renal trauma in children.

RESULTS

After drainage, the symptoms of abdominal distension gradually disappeared, and the physical examination shows that the abdomen gradually reduced to normal. The huge urinoma was cured by synchronous drainge. No complications occurred in short-term follow-up.

COMMENTS

The choice of surgical treatment is based on the degree and location of renal trauma. Grade IV injuries are a heterogeneous group and management should be tailored to the patient, especially among pediatric patients. Persistent urinary extravasation and/or symptomatic urinoma is a common complication of high-grade renal trauma, which will be amenable to ureteral stent placement or percutaneous drainage. For huge urinoma, synchronous percutaneous nephrostomy drainage and retrograde ureteral catheterization can relieve symptoms quickly.

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.

Primary versus deferred ureteroscopy for management of calculus anuria: a prospective randomized study

Introduction

Obstructive anuria can be managed by primary ureteroscopy (URS) or deferred URS after initial ureteral stenting. We want to compare the primary URS and deferred URS in the management of calculus anuria regarding the feasibility and clinical outcome.

Material and methods

Between January 2012 and December 2014, 150 patients with anuria due to ureteral calculi were prospectively randomized according to the timing of ureteroscopic intervention into two groups; deferred URS group (69 patients who were treated initially by ureteral stenting) and primary URS group (81 patients who were treated by emergency URS). Follow-up was at least 6 months postoperatively.

Results

Complete stone clearance was 87 % and 75.3% for deferred and primary URS groups, respectively (p = 0.097). Renal function normalized in 94.2% of deferred URS vs. 97.5% of primary URS (p = 0.414). Deferred URS group had a 2.9 % overall complication rate in comparison to 9.9 % for the primary URS group (p = 0.109). Ureteral perforation/pyelonephritis was noted in 6.2% of the primary URS group only (p = 0.043). The median number of maneuvers required until stone clearance was one (range 1–5) for primary URS vs. two (range 2–3) for deferred URS (p <0.001). The cost of primary URS was significantly less (p <0.001). On a multivariate analysis, lower ureteral calculi (OR 13.03, 95% CI 4.07– 41.7, p <0.001) and deferred URS (OR 2.84, 95% CI 1.07–7.49, p = 0.035) were independent predictors for an eventless and successful URS.

Conclusions

Primary URS for calculus anuria is feasible and cost-effective. It has a short hospital stay, but is still technically demanding. The perioperative complications are comparable to URS in normouric patients.

Early Stone Manipulation in Urinary Tract Infection Associated with Obstructing Nephrolithiasis

A urinary tract infection (UTI) and sepsis secondary to an obstructing stone are one of the few true urological emergencies. The accepted management of infected ureteral stones includes emergent decompression of the collecting system as well as antibiotic therapy. Despite this, no consensus guidelines clarify the optimal time to undergo definitive stone management following decompression. Historically, our institution has performed ureteroscopy with laser lithotripsy (URS-LL) treatment at least 1 to 2 weeks after decompression to allow for clinical improvement and completion of an antibiotic course. In this case series, we retrospectively review four cases in which patients had a documented UTI secondary to an obstructive ureteral stone. The patients underwent urgent decompression and, based on labs and clinical improvement, were subsequently treated with URS-LL. The presented patients received URS-LL within 5 days of decompression and antibiotics. The patients had no sepsis related postoperative complications from the accelerated course of treatment, resulting in discharge within 2 days following URS-LL. We provide a detailed examination of each patient presentation to describe our institution's experience with treating infected kidney stones within days of urgent decompression in order to question the previous standard of treating an infected kidney stone with a more delayed intervention.

Ureteral stents in urolithiasis

Ever since the ureteral stent design was fitted with a curl on both sides to prevent it from migrating up or down the ureter some 40 years ago, its use has gained tremendous momentum, aiding in the rise and evolution of endourology and has confidently kept its place in modern time urology. Over the past four decades, several designs, coating and biomaterials have been developed, trying to reduce infection, encrustation and other stent related symptoms. As the ideal stent has not yet been discovered, different ways of helping patients with their complaints have been researched. This review will cover these aspects of stent use in urolithiasis.

Clinical effectiveness in the diagnosis and acute management of pediatric nephrolithiasis

The incidence of pediatric nephrolithiasis has risen over the past few decades leading to a growing public health burden. Children and adolescents represent a unique patient population secondary to their higher risks from radiation exposure as compared to adults, high risk of recurrence, and longer follow up time given their longer life expectancies. Ultrasound imaging is the first-line modality for diagnosing suspected nephrolithiasis in children. Although data is limited, the best evidence based medicine supports the use of alpha-blockers as first-line MET in children, especially when stones are small and in a more distal ureteral location. Surgical management of pediatric nephrolithiasis is similar to that in adults with ESWL and URS first-line for smaller stones and PCNL reserved for larger renal stone burden. Clinical effectiveness in minimizing risks in children and adolescents with nephrolithiasis centers around ED pathways that limit CT imaging, strict guidance to ALARA principles or use of US during surgical procedures, and education of both patients and families on the risks of repeat ionizing radiation exposures during follow up and acute colic events.

[Management of ureteral obstruction : Value of percutaneous nephrostomy and ureteral stents]

Ureteral obstruction represents a heterogeneous disease pattern and is treated by ureteral stenting or percutaneous nephrostomy (PCN) depending on the necessity. The benefits of urinary diversion with ureteral stenting or PCN in malignant ureteral obstruction (MUO) for patient survival are only moderate. No differences have been found between ureteral stenting and PCN in MUO with regard to median patient survival and complication rates. In cases of MUO there is currently no evidence that urinary diversion improves the quality of life. Alternative concepts of ureteral stenting, such as tandem ureteral stents, metallic ureteral stents or metal mesh ureteral stents have not yet shown clear benefits. In benign ureteral obstruction, prospective randomized studies have demonstrated comparable quality of life after PCN or ureteral stenting. The method of choice for urinary diversion is influenced by the recommendations, personal experience of the clinician and the availability of the method.