[The 1-cm lower calyx calculus: SWT, URS or Mini-PCNL? Guidelines vs. reality.]

Urinary stones of the upper urinary tract can be considered a widespread public health concern due to their high incidence and prevalence and their health policy-related and financial implications. A significant proportion of newly diagnosed kidney stones are lower-pole stones, i.e., stones affecting the lower calyx group of the renal pelvicalyceal system. These are often diagnosed by chance, i.e., as incidental findings during ultrasound or CT scans performed for other reasons, or as "secondary stones" detected during the diagnostic work-up of symptomatic urinary stones in other locations. Residual disintegrates after extracorporeal shock-wave lithotripsy (ESWL) or endoscopic stone therapy constitute a further, quantitatively significant group. These incidentally discovered lower-pole stones are often characterised by their small size and lack of symptoms. It stands to reason that some of these small, asymptomatic lower-pole stones do not always remain small and asymptomatic, and that treatment tends to become more complex with increasing size. There has been an astonishing lack of published studies with a high level of evidence over the last 20 years to provide a conclusive and reproducible answer to the question posed in this review. Small, asymptomatic stones can be monitored. Symptomatic and rapidly growing stones should be treated. There is a lack of valid risk factors allowing an identification of subgroups that should be treated prophylactically at the asymptomatic stage. In active therapy, a 10-to-20-year-old principle still holds true today: a high stone-free rate in one therapy session is offset by an increased complication rate, with increasing miniaturisation in endourology (retrograde and percutaneous) and increasingly effective laser disintegration shifting this basic principle more and more in favour of flexible URS and (mini, micro) PCNL. The range of indications for ESWL is undoubtedly becoming smaller, and this also applies to lower-pole stones. The results of an ongoing prospective randomised study comparing the different treatment modalities, albeit with recruitment difficulties, are still pending.

Conversion therapy with pembrolizumab for a peritoneal metastasis of rectal cancer causing hydronephrosis in a patient with Lynch syndrome

A 44-year-old woman with Lynch syndrome was referred to our hospital for treatment of recurrence of microsatellite instability-high rectal cancer. [18F]Fluorodeoxyglucose (18FDG)-positron emission tomography revealed a peritoneal metastasis with invasion to the small intestine and left ureter. The peritoneal metastasis was diagnosed initially as unresectable because of extensive invasion to the left ureter requiring nephrectomy. Hence, first-line treatment with pembrolizumab was started. After the first course of pembrolizumab, she developed hydronephrosis and a resulting urinary tract infection (UTI). A percutaneous nephrostomy was performed to control the UTI. After six courses of pembrolizumab, 18FDG-positron emission tomography showed that the peritoneal metastasis was smaller with significantly reduced 18FDG uptake, and it was then diagnosed as resectable without nephrectomy. She underwent R0 resection of the peritoneal metastasis with partial resection of the small intestine. Intraoperatively, the peritoneal metastasis showed no invasion of the left ureter, allowing its preservation. The percutaneous nephrostomy was removed postoperatively, and she has not developed any subsequent UTIs. Histopathologically, the tumor showed a pathological complete response to pembrolizumab. To the best of our knowledge, this is the first case of conversion therapy with pembrolizumab for peritoneal metastasis with hydronephrosis.

Percutaneous treatment of stone containing calyceal diverticula: Strategies and outcomes from a University teaching hospital in a developing country

INTRODUCTION

There is a dearth of research available on the outcomes, complications, and recurrence rates of the modalities employed in treatment of diverticula after stone clearance by PCNL. We present our experience of various approaches employed in our institute for treatment of caliceal diverticulum after stone clearance by PCNL. We aimed to review the outcomes, complications, and recurrence rates of these procedures which can provide valuable insights into the effectiveness of these techniques in the treatment of stone containing caliceal diverticulum.

METHODS

A retrospective analysis of a prospectively maintained database of patients diagnosed with caliceal diverticular stone was conducted. The primary outcome was the stone-free rate (SFR) at the time of hospital discharge, determined by a combined nephroscopic/fluoroscopic assessment, and the obliteration of the diverticular sac. Secondary outcomes included the evaluation of operative time, duration of hospital stay and postoperative complications.

RESULTS

A total of 53 patients were evaluated. The mean diverticulum size was 23.2 mm, most common location was the superior calyx (30 (56.7%)). Group 1 (diverticular neck treatment + DJ stent) included 27 patients, group 2 (diverticular wall fulguration + PCN) included 18 patients and group 3 (PCN alone) included 8 patients. Mean operating time was highest in group 1 (80 min). Stone clearance was 100% in group 1, 91% in group 2 and 88% in group 3. Obliteration of caliceal diverticulum was highest in group 1 (90%). Mean duration of hospital stay was lowest in group 1 (3.2 days). Overall complications were lowest in group 2 (3/18).

CONCLUSION

PCNL followed by combination of diverticular wall fulguration and PCN or treatment of diverticular neck and DJ stenting is safe and effective in causing diverticular obliteration. Placement of nephrostomy tube alone was not found to be effective in causing diverticular obliteration in our study.

Assessing the Impact of Percutaneous Nephrostomy Presence on Neoadjuvant Treatment Quality in Patients With Muscle Invasive Bladder Cancer

INTRODUCTION

Symptomatic hydronephrosis associated with muscle invasive bladder cancer (MIBC) necessitates percutaneous nephrostomy (PCN) insertion before neoadjuvant chemotherapy (NAC). This study assesses the impact of PCN presence on standard intended NAC quality, its related complications and outcome after radical cystectomy (RC).

MATERIALS AND METHODS

The study comprises a retrospective, multicenter cohort of 193 consecutive RCs performed between 2016 and 2019. Eighty (42%) of these patients received NAC and were divided in 2 comparison groups by presence (n = 26; 33%) or absence (n = 54; 67%) of PCN. Endpoints included completion of adequate NAC treatment (cisplatin-based chemotherapy for at least 4 courses), complications during NAC, post-RC complications and hospital stay.

RESULTS

Overall, patients with PCN (45/193; 23%) featured a higher referral rate to NAC (58% vs. 36%, P = .01), worse glomerular filtration rates (P < .001) and more adverse events (P = .04), in comparison to non-PCN patients. In the NAC cohort, PCN patients had less adequate treatment rates (54% vs. 85%, P = .005), and more infections (35% vs, 7%; P = .008) and hospitalizations (58% vs. 13%; P < .001) during chemotherapy. Post-RC outcome was similar for both comparison groups. PCN was an independent risk factor for inadequate NAC (OR = 3.9, P = .04), and infections (OR = 11.3, P = .01) and hospitalizations (OR = 7.5, P = .004) during NAC.

CONCLUSIONS

PCN in MIBC patients is a significant risk factor for inadequate NAC and adverse events during treatment. This finding may quire the rationale of NAC, potentially leading to consideration of NAC avoidance and upfront RC in PCN patients. Further survival studies with long follow-up are needed for elucidating this issue.

Results of Temporary Drainage of Poorly Functioning Kidneys With Ureteropelvic Junction Obstruction: Does the Histology of Persistent Poor Functioning Kidneys Indicate an Increased Risk of Hypertension?

OBJECTIVE

To review our experience with managing poorly functioning kidneys with ureteropelvic junction obstruction (PFK-UPJO) with differential renal function (DRF) <10% by a trial of temporary drainage, as the management of such kidneys is controversial. We also studied the histopathologic changes in the nephrectomy specimens of persistent PFK-UPJO, as tubulointerstitial damage may predispose to hypertension.

METHODS

A retrospective review of cases undergoing treatment for unilateral UPJO over 5-year period in 2 centers was conducted. In PFK-UPJO, 4-6 weeks trial of drainage with double J stent or percutaneous nephrostomy was employed. Those kidneys that improved DRF to >10% underwent pyeloplasty, while persistent PFK underwent nephrectomy; the specimens were studied for interstitial fibrosis/tubular atrophy (IF/TA), arterial lesions, and arteriole lesions.

RESULTS

Of 402 patients with unilateral UPJO that underwent surgical management, 17 (4.1%) had PFK-UPJO. After 4-6 weeks trial of drainage, 6 kidneys (35.2%) with improved DRF underwent pyeloplasty, while 11 kidneys with persistent PFK underwent nephrectomy; significant IF/TA, arterial, and arteriolar changes were noted in 9 (82%), 9 (82%), and 4 (36%) kidneys, respectively, including 7 kidneys in normotensive children. Two (11.7%) children had hypertension at presentation; 1 child remains hypertensive even after nephrectomy.

CONCLUSION

In PFK-UPJO, trial of temporary drainage seems appropriate to decide plan of management; 35% of such kidneys improved function after drainage. Most persistent PFK demonstrated severe and irreversible histologic changes that may predispose to hypertension if they are preserved, and we suggest that such kidneys may be removed. Long-term follow-up of all preserved PFK-UPJO is strongly recommended.

Management of malignant ureteric obstruction with ureteric stenting or percutaneous nephrostomy

Malignant ureteric obstruction (MUO) is frequently encountered in patients with advanced cancers. In the largest study to date, assessing 852 patients from across Scotland, the authors demonstrated the presence of MUO as a marker of advanced disease across cancer types, with poor survival for many patients, even with intervention. There is uncertainty in optimal management of this condition, with marked differences in management between hospitals. Treatment to relieve the obstruction does not guarantee either improvement in kidney function or progression to further oncological treatment. The authors have developed a prognostic tool to estimate outcomes after intervention for MUO, and advocate its use for clinicians along with other data presented for patient counselling.

Is it Safe to Continue Aspirin in Patients Undergoing Percutaneous Nephrolithotomy?

OBJECTIVE

To evaluate peri-operative outcomes in patients on chronic aspirin therapy undergoing percutaneous nephrolithotomy (PCNL), with and without discontinuation of aspirin. Anti-coagulation and anti-platelet therapy are contraindications for PCNL per American Urological Association guidelines due to bleeding risk. However, there is potentially increased cardiovascular risk with peri-procedural aspirin withdrawal.

METHODS

Patients on chronic aspirin undergoing PCNL between January 2014 and May 2019 were retrospectively reviewed and stratified by continued or discontinued aspirin >5 days preoperatively. Hematologic complications, transfusions, and thrombotic complications were assessed with logistic regression model.

RESULTS

Three hundred twenty-five patients on chronic aspirin therapy underwent PCNL-85 continued and 240 discontinued aspirin. There were no significant differences in hemoglobin change, estimated blood loss, transfusions, creatinine change, thrombotic complications, 30-days re-admissions, complications, or 30-day emergency department visits. Patients who continued aspirin had longer length of stay (1.6 vs 1.9 days, P = .03). American Society of Anesthesiologists (ASA) score of 3 (OR 3.2, P = .02, 95% confidence intervals (CI) [1.2-8.4]), ASA score of 4 (OR 4.0, P = .02, 95% CI [1.2-13.1]), Black race, and previous smoking (OR 2.1, P = .02, 95% CI [1.1-3.9]) was associated with continued aspirin. Body mass index ≥30 was associated with aspirin discontinuation (OR 0.9, P = .004, 95% CI [0.9-1.0]). Increased postoperative hematologic complications were associated with additional anticoagulation medication (OR 2.9, P = .04, 95% CI [1.0-4.4]).

CONCLUSION

Continued aspirin use did not increase in postoperative complications in patients undergoing PCNL. Patients who are on additional anticoagulation medication are at risk of hematologic complications.

Training ultrasound-guided percutaneous nephrostomy technique with porcine model

PURPOSE

There is increasing interest in the use of ultrasound for endoscopic and percutaneous procedures. Access can be achieved without radiation exposure under ultrasound guidance. Our aim was to develop a porcine-based training model for ultrasound-guided percutaneous renal access that could also be personalized to a specific patient.

MATERIALS AND METHODS

The Institutional Animal Care and Use Committee of Severance Hospital approved the study protocol. An anesthetized pig was placed in the dorsal lithotomy position. For the nephrostomy puncture, a Chiba biopsy needle with an echo tip was used under ultrasound guidance. Eight residents and three consultants in urology participated. Puncture time was defined as the nephrostomy time to confirm the flow of irrigation via the needle. After training, satisfaction survey results for clinical usability and procedural difficulty were evaluated.

RESULTS

The 5-point Likert scale satisfaction survey for clinical usability and procedural difficulty found mean results of 4.64 and 4.09 points, respectively. There were no differences between residents and consultants for either variable. For all participants combined, there was a significant difference for nephrostomy time between the first and second trials (278.8±70.6 s vs. 244.5±47.0 s; p=0.007). The between-trial difference was greater for residents (291.5±71.2 s vs. 259.1±41.9 s; p=0.039). The difference for the consultant was not significant (245.0±69.4 s vs. 205.7±42.5 s; p=0.250).

CONCLUSIONS

We developed a porcine-based ultrasound-guided nephrostomy puncture training model. Satisfaction survey results indicated high clinical usability and procedural difficulty. For nephrostomy time, the model was more effective for urology residents than for consultants.

Incidence of urinary tract infections in patients with permanent percutaneous nephrostomy after implementation of a standardized care program

INTRODUCTION

Percutaneous nephrostomy tubes (PNT), which are used in some cancer hospitals, are associated with an increase in urinary tract infections (UTI).

OBJECTIVE

To determine the impact of a standardized care program on the incidence of UTIs requiring hospitalization (UTI-RH).

MATERIAL AND METHODS

Retrospective study that included patients with a first PNT inserted. The incidence, relative risk (RR), costs and outcomes of patients with UTI-RH were compared during the period before (P0) vs. after the intervention (P1).

RESULTS

113 PNTs were inserted during P0, and 74 at P1. During P0, 61 patients (53.9%) experienced 64 UTI-RH events in 22,557 PNT days. At P1, four patients (5.4%) had a UTI-RH in 6,548 PNT days (IRR: 0.21, 95% CI: 0.05-0.57). The RR was 0.09 (95% CI: 0.03-0.25). Monthly cost per day/bed was USD 3,823 at P0 and USD 1,076 at P1, and for antibiotics, it was USD 790 at P0 and USD 123.5 at P1.

CONCLUSIONS

This study highlights the importance of a standardized care program for permanent percutaneous devices, since this reduces antibiotic use, hospitalization, and the cost of care.

National consensus survey on management approaches for upper urinary tract obstruction: A comparative analysis of retrograde ureteric stent and percutaneous nephrostomy

To the Editor, Upper urinary tract obstruction (UUTO) is a common scenario in clinical practice, and it is caused by a variety of diseases. Lithiasis, tumours and strictures are some of the principal aetiologies. Multiple factors may influence both the need for decompression of the obstructed collecting system and the urgency of procedure...

Effect of preoperative prophylactic antibiotic use on postoperative infection after percutaneous nephrolithotomy in patients with negative urine culture: a single-center randomized controlled trial

PURPOSE

To compare the effects of different preoperative antibiotic prophylaxis (ABP) regimens on the incidence of sepsis after percutaneous nephrolithotomy (PCNL) in patients with negative urine culture.

METHODS

A single-center, randomized controlled trial (June 2022-December 2023) included 120 patients with negative preoperative urine cultures for upper urinary tract stones who underwent PCNL (chictr.org.cn; ChiCTR2200059047). The experimental group and the control group were respectively given different levofloxacin-based preoperative ABP regimes, including 3 days before surgery and no ABP before surgery. Both groups were given a dose of antibiotics before the operation. The primary outcome was differences in the incidence of postoperative sepsis.

RESULTS

A total of 120 subjects were included, including 60 patients in the experimental group and 60 patients in the control group. The baseline characteristics of the two groups were comparable and intraoperative characteristics also did not differ. The sepsis rate was not statistically different between the experimental and control groups (13.3% vs.13.3%, P = 1.0). A multivariate logistic regression analysis revealed that body mass index (BMI) (OR = 1.3; 95% CI = 1.1-1.6; P = 0.003) and operating time (OR = 1.1; 95% CI = 1.0-1.1; P = 0.012) were independent risk factors of sepsis.

CONCLUSION

Our study showed that prophylactic antibiotic administration for 3 days before surgery did not reduce the incidence of postoperative sepsis in patients with negative urine cultures undergoing PCNL. For this subset of patients, we recommend that a single dose of antibiotics be given prior to the commencement of surgery seems adequate.

Vacuum-Assisted vs Conventional Minimally Invasive Percutaneous Nephrolithotomy for the Treatment of Two-to-Four-Centimeter Stones: A Multicenter Prospective and Randomized Trial

Introduction: Percutaneous nephrolithotomy (PCNL) is the recommended treatment for 2-4-cm renal stones. Minimally invasive PCNL (MPCNL) with ≤22F sheath was frequently used instead of standard PCNL. MPCNL uses pressurized irrigation to flush out stone fragments through a conventional nephrostomy sheath (cNS), which may result in higher intrarenal pressure (IRP) and longer operating time. The novel vacuum-assisted nephrostomy sheath (vaNS) was developed to mitigate higher IRP and to facilitate stone removal. It might improve the performance of MPCNL. This prospective and randomized trial compares these two sheaths. Materials and Methods: In total, 120 patients with 2-4-cm renal stones were accrued in six tertiary medical centers with equal numbers in 2021. In total, 120 patients underwent mPCNL, 60 using 18F cNS and 60 using 18F vaNS, in a prospective and randomized assignment. The primary outcome measurement is decrease in IRP. The secondary outcome is efficacy in stone retrieval. Results: The IRP was lower with vaNS than with cNS: mean IRP during lithotripsy was 12.0 ± 2.7 mm Hg with vaNS vs 20.4 ± 6.0 mm Hg with cNS, p = 0.000. IRP duration ≥30 mm Hg was shorter with vaNS than with cNS (6.7 ± 7.4 seconds vs 113.4 ± 222.7 seconds, p = 0.001). vaNS has shorter stone removal time (26.9 ± 14.3 minutes vs 35.7 ± 11.8 minutes, p = 0.000). Stone extraction rate was higher (166.4 ± 88.1 mm3/min vs 90.4 ± 31.7 mm3/min, p = 0.000). Stone grasper usage was less (1.4 ± 2.6 vs 11.9 ± 9.7, p = 0.000). vaNS maintained the safety profile. Blood loss, creatinine changes, perioperative complications, and hospital stays were the same in both groups, all p > 0.05. Conclusion: MPCNL for stones 2-4 cm using vaNS has shorter stone removal time, higher stone extraction rate, and less use of stone extractor. vaNS is superior to cNS at reducing IRP and is associated with improved stone free rates at 3 days but not at 30 days postoperatively. The trial was registered with Chinese Clinical Trial Registry (ClinicalTrials.gov, NCT ChiCTR2000039681).

Emergency decompression for patients with ureteral stones and SIRS: a prospective randomized clinical study

OBJECTIVE

Patients with ureteral calculi and systemic inflammatory response syndrome (SIRS) often require emergency drainage, and percutaneous nephrostomy (PCN) and retrograde ureteral stent insertion (RUSI) are the most commonly used methods. Our study aimed to identify the best choice (PCN or RUSI) for these patients and to examine the risk factors for progression to urosepsis after decompression.

METHODS

A prospective, randomized clinical study was performed at our hospital from March 2017 to March 2022. Patients with ureteral stones and SIRS were enrolled and randomized to the PCN or RUSI group. Demographic information, clinical features and examination results were collected.

RESULTS

Patients (n = 150) with ureteral stones and SIRS were enrolled into our study, with 78 (52%) patients in the PCN group and 72 (48%) patients in the RUSI group. Demographic information was not significantly different between the groups. The final treatment of calculi was significantly different between the two groups (p < .001). After emergency decompression, urosepsis developed in 28 patients. Patients with urosepsis had a higher procalcitonin (p = .012) and blood culture positivity rate (p < .001) and more pyogenic fluids during primary drainage (p < .001) than patients without urosepsis.

CONCLUSION

PCN and RUSI were effective methods of emergency decompression in patients with ureteral stone and SIRS. Patients with pyonephrosis and a higher PCT should be carefully treated to prevent the progression to urosepsis after decompression.Key messageIn this study, we evaluate the best choice (PCN or RUSI) for patients who have ureteral stones and SIRS and to examine the risk factors for progression to urosepsis after decompression. This study found that PCN and RUSI were effective methods of emergency decompression. Pyonephrosis and higher PCT were risk factors for patients to develop to urosepsis after decompression.

Mini-versus standard percutaneous nephrolithotomy in pediatric population: A randomized controlled trial

INTRODUCTION

Mini PCNL has gained popularity in adult patients due to reduction in the complication rate with comparable stone free rate. There is paucity of level 1 evidence regarding the benefit of mini PCNL in the pediatric group.

OBJECTIVE

We performed a randomised study to compare mini PCNL (mPCNL) with standard PCNL (sPCNL) for the management of renal calculi in patients less than 18 years of age in terms of safety, efficacy, and stone-free rate (SFR).

MATERIALS AND METHODS

A randomised controlled trial was performed on 50 children who underwent PCNL from June 2015 to March 2021, who were divided into two groups. Group I had 25 patients managed with mPCNL (sheath size 16.5 Fr) and Group II had 25 patients who underwent sPCNL (sheath size 26 Fr). Primary outcomes including stone free rates (SFR) and hemoglobin drop and secondary outcomes like operative time, complications, pain score, need of analgesia, incidence of nephrostomy site leak, hospital stay in days were compared between the two groups.

RESULTS

The mean age of patients in groups I and II was 9.4 ± 2.6 and 10.4 ± 2.26 years, respectively (p = 0.15). The mean stone sizes in both groups I and II were 18.6 ± 2.56 and 20.2 ± 3.58 mm, respectively (p > 0.05). The stone free rate for group I was 88% and for group II, 92% (p = 0.64). The average drop in hemoglobin was higher in group II compared to group I (1.1 ± 0.31 g/dl and 1.7 ± 0.23 g/dl respectively; p < 0.0001), however the mean blood transfusion rate was not significantly different in both groups. The operating time was shorter in group II compared to group I (p-value - 0.0030). The pain scores were lesser for the group I. Grade I complications were higher in group II as compared to group I (p-0.047); however, grade II complications were comparable in both groups. The mean hospital stay was not significantly different in both groups.

DISCUSSION

This study confirms the role of mini PCNL in pediatric patients with renal stones. The stone clearance rate of mini PCNL is equivalent to standard PCNL, with lesser blood loss and postoperative complications, however with longer operative time during mPCNL. The small number of the participants in both arms is a limitation of this study and may also reflect fewer children with urolithiasis being treated surgically even in a tertiary care referral centre.

CONCLUSIONS

Mini-PCNL offers equivalent stone free outcome with lower complications rate compared to the standard PCNL for all types of renal stones.

Percutaneous Nephrolithotomy in Anomalous Kidney

OBJECTIVE

To assess the stone-free rate (SFR) subsequent to percutaneous nephrolithotomy (PCNL) in patients with anatomically anomalous kidneys.

STUDY DESIGN

Cross-sectional study. Place and Duration of the Study: Department of Urology, Sindh Institute of Urology and Transplantation Karachi, from 23 July 2020 till 30 October 2021.

METHODOLOGY

Sixty-five patients of renal stone disease with abnormal kidneys, aged 18-60 years of both genders were enrolled in this cross-sectional study. Demographic information like age, gender, stone size, duration of disease, and type of abnormality were noted. After PCNL, stone-free status was determined after 2 weeks of the procedure by performing ultrasound KUB.

RESULTS

A total of 65 patients were included in this study with mean age of 36.37 ± 12.86 years [Range: 18-60]. There were 76.9% of males and 23.1% of females. Regarding anatomical malformation, 46.2% were malrotated kidneys, 16.9% were horseshoe kidneys, 16.9% were partial Duplex system, 9.2% had bifid pelvis. Median duration of the disease was 12 (IQR=10). Forty-one patients (63.1%) had single and 24 (36.9%) had multiple number of stones with average size of 3.26 ± 1.14 cm. SFR after PCNL in patients with abnormal kidneys was 70.77% (46/65) while 29.23% (19/65) were observed with residual fragments. Out of 19 cases with residual fragments, 10 (53.2%) had stone size <1 cm and 9 (47.4%) had stone of 1 to 3 cm. Sixteen out of 19 patients with residual stones were treated with ESWL (most required: one session), and re-do PCNL was performed in three cases.

CONCLUSION

PCNL is an effective and safe operation in anatomically anomalous kidneys. For satisfactory outcomes, it requires extreme care and exceptional surgical skill.

KEY WORDS

Malrotated kidney, Duplex system, Kidney anomaly, Horseshoe kidney, PCNL, Extracorporeal shockwave lithotripsy (ESWL).

Paediatric percutaneous nephrolithotomy (P-PCNL) reporting checklist

OBJECTIVE

To develop a reporting checklist that serves to improve and standardise reporting in studies pertaining to paediatric percutaneous nephrolithotomy (PCNL).

METHODS

Based on findings from systematic review of literature, a draft list of items was formulated. By process of review and revisions, a finalised version was established and consensus achieved.

RESULTS

The finalised version of the checklist covers four main sections, which include the following areas: study details, pre-operative, operative and post-operative information. There are 18 further sub-items. Recommendations deemed to be of high importance to include are highlighted in bold.

CONCLUSION

This practical tool can aid clinicians and researchers when undertaking and reviewing studies on paediatric PCNL. This is highly relevant given the current heterogeneity that exists as well as debate in best practice patterns.

Does High Ventilation Mode Affect the Success Rates of Retrograde Intrarenal Surgery? A Single-Blind Randomized, Prospective, Single-Center Study

Purpose: Retrograde intrarenal surgery (RIRS) has been accepted as a first-line therapeutic option for kidney stones <2 cm. Renal mobility might be a challenging situation for the surgeon targeting the laser, thereby limiting the renal mobility during surgery might affect the surgical success. The main objective of the present trial was to evaluate the effect of two different ventilation modes on the efficacy and safety of RIRS performed under general anesthesia. Materials and Methods: The patients undergoing RIRS from January 2023 to April 2023 were prospectively enrolled in the trial. In the standard ventilation (SV) mode, the tidal volume was 8 to 10 mL/kg with respirations per minute being 10-15, whereas in the high ventilation (HV) mode the tidal volume was reduced to 6 to 8 mL/kg with the frequency being increased to 15 to 18 respirations/minute. For the purposes of the trial and the randomization, the anesthesiologist was informed about the ventilation mode used, whereas the surgeon was blinded. The surgical success rates and the observed complications were compared between SV and HV modes. Results: A total of 144 patients were enrolled with the mean age 48.78 ± 14.16 years. The mean duration of operation was 62.9 ± 26.3 minutes in the SV group, whereas it was 58.4 ± 20.1 minutes in the HV group (p = 0.031). Fragmentation rate of the stones per minute was higher in the HV group with the difference being statistically significant (p = 0.003). In the preoperative period, while hematuria was seen at higher rates in the HV group, the difference was not statistically significant (p = 0.671). Stone-free rates (Grades A-B-C) and the rates of postoperative complications were comparable between the groups (p = 0.605 and p = 0.676, respectively). Conclusion: Using HV mode during the RIRS decreased the operative time and provided the surgeon with the ability to target the laser more effectively. Surgeons might prefer using the HV mode during RIRS in a mobile kidney to reduce their operative time and perform comfortable surgery. ClinicalTrials.gov: The trial is registered at ClinicalTrials.gov with the registration number of NCT05792670.

PCNL vs RIRS in management of stones in calyceal diverticulum: outcomes from a global multicentre match paired study that reflects real world practice

INTRODUCTION

Calyceal diverticulum (CD) is the outpouching of a calyx into the renal parenchyma, connected by an infundibulum. Often associated with recurrent stones, common surgical options include percutaneous nephrolithotomy (PCNL) or retrograde intrarenal surgery (RIRS). We aim to present the real-world practises and outcomes comparing both approaches and the technical choices made.

MATERIALS AND METHODS

Retrospective data including 313 patients from 11 countries were evaluated. One hundred and twenty-seven underwent mini-PCNL and one hundred and eighty-six underwent RIRS. Patient demographics, perioperative parameters, and outcomes were analysed using either T test or Mann-Whitney U test. Categorical data between groups were analysed using the Chi-squared test. Propensity score matching (PSM) was performed matching for baseline characteristics. Subgroup analyses for anomalous/malrotated kidneys and difficult diverticulum access were performed.

RESULTS

After PSM, 123 patients in each arm were included, with similar outcomes for stone-free rate (SFR) and complications (p < 0.001). Hospitalisation was significantly longer in PCNL. Re-intervention rate for residual fragments (any fragment > 4 mm) was similar. RIRS was the preferred re-intervention for both groups. Intraoperative bleeding was significantly higher in PCNL (p < 0.032) but none required transfusion. Two patients with malrotated anatomy in RIRS group required transfusion. Lower pole presented most difficult access for both groups, and SFR was significantly higher in difficult CD accessed by RIRS (p < 0.031). Laser infundibulotomy was preferred for improving diverticular access in both. Fulguration post-intervention was not practised.

CONCLUSION

The crux lies in identification of the opening and safe access. Urologists may consider a step-up personalised approach with a view of endoscopic combined approach where required.

Impact of drainage catheter material, size, and anti-dislodgement mechanism on percutaneous nephrostomy exchange intervals: a systematic review protocol

Background: Percutaneous nephrostomy (PCN) is a commonly performed procedure by interventional radiology and urology to treat urinary obstruction. In this procedure, a catheter is percutaneously placed into the renal pelvis for urinary diversion or hemorrhagic cystitis. Material type, catheter size, and catheter shape (anti-dislodgement feature) ultimately contribute to the inherent traits of longevity in drainage catheter device. Reviewing the relative strengths or weaknesses of products in the existing clinical market may help clinicians critically appraise the devices they use with evidence-based findings from this review. Furthermore, a deeper understanding of the relative strengths and weaknesses of existing devices may help inform the next generation of drainage catheter devices to prolong the interval between exchanges without detriment to patient safety. Methods: The following electronic databases will be queried: PubMed, Web of Science, Cochrane from their inception to January 2023 to identify randomized controlled trials (RCTs) and cohort studies to investigate the differences that our interventions of catheter material, size, and dislodgement mechanism will have on the exchange interval (standard of care 90 days vs. 60 days vs. 45 days vs. 30 days). The primary outcomes will be the drainage catheter exchange frequency. Ethics and dissemination: We aim to share our findings through high-impact peer reviewed journals. As drainage catheters and minimally invasive interventional radiology procedures become more popular, it is important for healthcare providers taking case of these populations to understand which variables might optimize patient care and minimize emergent exchanges. Data will be made available to readers. Registration: PROSPERO ( CRD42023432788, 16 June 2023).

Needle-Perc-Assisted Endoscopic Surgery in Treatment with Renal Staghorn Stones: A Prospective Randomized Controlled Study from a Large-Volume Stone Center

INTRODUCTION

The goal of this study was to evaluate the efficacy and safety of needle-perc-assisted endoscopic surgery (NAES) in the treatment of staghorn renal stones via a single-center prospective randomized controlled study.

METHODS

A total of 219 patients with partial or complete staghorn renal stones were prospectively randomized into two groups between January 2020 and April 2022. In group A (n = 112), patients were treated with traditional standard access, multiple if necessary, and in group B (n = 107), only one standard access was made, and needle-perc was assisted to remove the residual stones in the same stage. All procedures were guided under ultrasound totally. Stone size, operating time, blood loss, pain score, complications, and other related characteristics were monitored and analyzed.

RESULTS

Procedures were successful in all patients. The baseline characters were similar between the groups. The mean stone size was comparable (4.5 ± 1.4 vs. 4.7 ± 1.7, p = 0.35). The 1-month stone-free status was achieved in 85 patients (75.9%) in group A and 80 (74.8%) patients in group B (p = 0.72). The operation time was shorter in group A than B (75.1 ± 28.1 min vs. 97.2 ± 20.4 min, p = 0.02). A less blood loss (p = 0.01), shorter hospital stay (p = 0.04), lower pain score (p = 0.04), and lower severe complication rates (p = 0.03) were observed in group B.

CONCLUSION

NAES reveals better postoperative recurrence compared with traditional multiple tracts method for treating staghorn renal stones. The stone-free rate was comparable between the two groups.

Efficacy and safety of minimally invasive percutaneous nephrolithotomy versus retrograde intrarenal surgery in the treatment of upper urinary tract stones (> 1 cm): a systematic review and meta-analysis of 18 randomized controlled trials

BACKGROUND

The advantages and disadvantages of retrograde intrarenal surgery (RIRS) and minimally invasive percutaneous nephrolithotomy (mPCNL) for treatment of upper urinary tract calculi have not been conclusively determined.

METHODS

In this meta-analysis, We comprehensively evaluated the performance of the two surgical approaches in treatment of upper urinary calculi. We searched the Pubmed, Embase, Cochrane and Web of science databases for randomized controlled trial (RCT) articles on RIRS and mPCNL upto December 2022. Data were extracted by two independent reviewers and subjected to the meta-analysis using the Stata 15.1 software (StataSE, USA).

RESULTS

A total of 18 eligible RCTs involving 1733 patients were included in this study. The meta-analysis revealed that mPCNL of 1-2 cm or 2-3 cm stones had a higher stone clearance rate (RR:1.08, 95%CI (1.03, 1.14), p = 0.002) and shorter operation time (WMD : -10.85 min, 95%CI (-16.76, -4.94), p<0.001). However, it was associated with more hospital stay time (WMD :1.01 day, 95%CI(0.53, 1.5), p<0.001), hemoglobin drops (WMD :0.27 g/dl, 95%CI (0.14, 0.41), p<0.001), blood transfusion rate (RR:5.04, 95%CI(1.62, 15.65), p = 0.005), pain visual analogue score (WMD:0.75, 95%CI (0.04, 1.46), p = 0.037), hospital costs (SMD :-0.97, 95%CI (-1.19, -0.76), p<0.001) and major complications (RR:1.89, 95%CI(1.01, 3.53), p = 0.045).

CONCLUSION

Therefore, in terms of surgical effects and operation time, mPCNL is superior to RIRS, but is inferior with regards to other perioperative parameters. These factors should be fully considered in clinical decision making.

Supine mini percutaneous nephrolithotomy in horseshoe kidney

OBJECTIVE

The percutaneous nephrolithotomy (PCNL) in Horseshoe kidneys (HSK) is usually performed in the prone position, allowing entry through the upper pole and providing good access to the collecting system. However, in patients with normal kidney anatomy, the supine position is reliable and safe in most cases, but it is unknown whether the supine position is adequate in patients with HSK. The purpose of this study was to describe the results of PCNL in HSK in three different surgical institutions and to evaluate the impact of supine position during surgery, comparing pre-operative and post-operative data, complications, and stone status after surgery.

MATERIAL AND METHODS

Between 2017 and 2022, a total of 10 patients underwent percutaneous renal surgery for stone disease in HSK. All patients were evaluated pre- and post- operatively with non-contrast CT. we evaluated patients (age and gender), stones characteristics (size, number, side, site and density ), and outcomes. The change in haemoglobin, hematocrit, creatinine and eGFr were assessed between the most recent preoperative period and the first postoperative day. Procedure success was defined as stone-free or presence of ≤4 mm fragments (Clinically Insignificant residual Fragments - CIrF). Complications were registered and classified according to Clavien-dindo Grading System, during the 30 - day postoperative period and Clavien scores ≥ 3 were considered as major complications. Statistical analysis was performed using "r 4.2.1" software, with a 5% significance level. we also compared pre-operative and post-operative data using "wilcoxon signedrank test".

RESULTS

No statistical difference was observed between preoperative and post-operative renal function data. At one post operative day CT scan, an overall success rate of 100% was registered. 9/10 patients were completely free from urolithiasis (stone-free rate: 90%), while 1/10 patients had ≤4 mm residual stone fragments (CIrF rate: 10%). No cases of intraoperative complications were registered. Post-operative complications were reported in 1/10 patients. A patient developed urosepsis (defined as SIrS with clinical signs of bacterial infections involving urogenital organs - Clavien-dindo Grade II) after procedure, and was treated with intravenous antibiotic therapy successfully.  Conclusions: This study shows that in patients with HSK mini- PCNL in supine position allows to achieve good stone free rate with a very low morbidity. According to our series, the described technique for PCNL in HSK should be an option. Nevertheless these results must be confirmed by further studies.