Retrograde intrarenal surgery for urinary stone disease in patients with solitary kidney: A retrospective analysis of the efficacy and safety

Safety and Efficacy of Retrograde Intrarenal Surgery in the Solitary Kidney: A Propensity Score-Matched Analysis of the RIRSearch Study Groups' Results

Background: The aim of this study was to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) in patients with renal calculi with solitary kidneys (SKs). Materials and Methods: In this retrospective, multicenter study, a matched case-control study was carried out using the data from 522 RIRS patients treated between 2014 and 2021. Patients' demographic data, stone characteristics, operative outcomes, perioperative and postoperative complications, and surgical success were analyzed. All patients were evaluated with noncontrast-enhanced computed tomography (NCCT) preoperatively and 1 month after the surgery. Surgical success was defined as no evidence of remaining residual fragments of <3 mm in the first-month postoperative NCCT images. The case group of 29 patients with SKs (Group 1) treated with RIRS were matched with 76 control patients (Group 2) with bilateral kidneys, who underwent unilateral RIRS by propensity score-matched (PSM) analysis. Results: After PSM analysis, the demographic and clinical data did not differ significantly between the groups. The stone burden was similar between the groups: 733.6 mm3 (range: 50.4-7565.9) versus 991.1 mm3 (range: 201.2-4380.6) (P = .09), respectively. The perioperative complication rates were 13.8% (n = 4) in Group 1 and 11.8% (n = 9) in Group 2 (P = .78). There was no statistically significant difference between the groups for postoperative complication rates (minor complications, classified as Clavien 1 or 2), (6.9% [n = 2] versus 13.2% [n = 10; P = .34]), respectively. Surgical success was 82.8% (n = 24) in Group 1 and 83.6% in Group 2 (P = .92). There was no significant difference between preoperative and postoperative glomerular filtration rate and creatinine values (P = .005). Conclusions: Our results support that RIRS is a safe and effective treatment method in SK patients with similar complication and stone-free rates compared to patients who had bilateral functional kidneys and underwent unilateral RIRS.

Needle-perc-assisted endoscopic surgery (NAES) for patients with complicated solitary kidney stones: a prospective randomized study from a single center

PURPOSE

The goal of this study is to compare traditional percutaneous nephrolithotomy (PCNL) and needle-perc-assisted endoscopic surgery (NAES) in the treatment of complicated solitary kidney stones via a single-center randomized controlled prospective study.

METHODS

A total of patients with complex (Guy's score II-IV) solitary kidney stones between July 2019 to June 2022 were enrolled in the study. Participants were stratified into two groups: needle-perc-assisted endoscopic surgery group (group A) and traditional PCNL group (group B). All procedures were finished by X-ray free technique. The clinical characteristics and outcomes were analyzed.

RESULTS

A total of 90 (44 in Group A and 46 in Group B) patients were finally included in our study. There were no statistically differences in terms of gender, age, body mass index (BMI), stone burden between two groups. The mean operative duration of Group A was significant higher than group B (95.1 ± 21.4 min vs 72.5 ± 29.5 min, p=0.02). The 1-month stone-free rate (SFR) was significant higher in Group A than B (90.9% vs 73.9%, p=0.03). A less hemoglobin drop (p=0.01), shorter postoperative in-hospital day (p=0.04), and lower severe complication (Clavien-Dindo III and above) rates (p=0.03) were observed in Group A.

CONCLUSION

For patients with solitary kidney stones, NAES technique provides a higher one-session SFR, a better renal function recovery and compared with traditional PCNL.

Retrograde intrarenal surgery for the treatment of renal stones in patients with a solitary kidney: Does access sheath matter?

Background

Treating renal stones in patients with a solitary functioning kidney is challenging. The present study was aimed to assess the competence and safety of retrograde intrarenal surgery (RIRS) for the treatment of renal stones in a solitary kidney.

Methods

Between August of 2017 and August of 2019, 25 ensuing patients with a solitary kidney and renal calculi and who were treated with RIRS were prospectively enlisted in the study. All patients were assessed by non-contrast computed tomography before surgery. Stone-free status was determined if there were no residual fragments. The final stone-free rates (SFRs) were assessed 3 months after the last treatment session by plain X-ray KUB and ultrasonography. Patient demographics, perioperative and postoperative outcomes were prospectively evaluated. Serum creatinine levels and glomerular filtration rate (GFR) pre-procedure and during follow-up were correlated.

Results

Twenty-five patients underwent 26 procedures. The mean patient age was 42.81 ± 12.3 (range 22–67) years. The mean stone size was 18.23 ± 6.27 mm (range 9–25 mm) and the mean operative time was 46.15 ± 15.34 min (range 25–100 min). A ureteral access sheath (UAS) was used in five (19.2%) pre-stented patients. One patient (3.8%) required the second stage RIRS for residual stones. The SFR after the initial and final procedures, the SFR was 84% and 92%, respectively.

The mean serum creatinine levels were significantly reduced post-surgery compared to preoperative levels (1.76 ± 1.21 mg/dL; 1.37 ± 0.60 mg/dL; p value 0.001) while GFR not encounter any significant variation post-surgery (63.04 ± 33.16 ml/min) compared to preoperative rates (61.12 ± 34.76 ml/min, p value 0.502). Minor complications classified as Clavien I or II developed in 5 patients (20%). Clavien IIIb, a major complication, developed in one (4%) patient, which was caused by steinstrasse and necessitated emergency surgical intervention.

Conclusion

Renal stones in a solitary kidney can be managed using RIRS safely and effectively with and without the use of UAS, without compromising renal function.

Do we have a limit for retrograde intrarenal surgery for solitary kidney stone?

OBJECTIVE

The management of urolithiasis in patients with a solitary kidney is challenging for urologists. This study aimed to evaluate the safety of retrograde intrarenal surgery (RIRS) in the treatment of stones in patients with solitary kidney and to reply to the question if there is any limit for this surgery.

METHODS

Between January 2016 and December 2019, we enrolled 52 patients who had a solitary kidney and underwent RIRS. We collected data on preoperative patient characteristics, stone dimensions, and postoperative outcomes. Stone size, duration of operation, duration of fluoroscopy, type of anesthesia, and degree of surgical complication were evaluated retrospectively. Surgeries performed in less and more than 60 minutes and with and without complications were compared.

RESULTS

A total of 52 patients with a kidney stone and a solitary kidney were evaluated. The mean stone size was 14 ± 0.4 cm and surgical success rate was 87.3%. In our study, 13 patients (24.5%) had grade 1 minor complications, and none required a blood transfusion. The mean operation time was 51.9 ± 17.3 minutes. The postoperative creatinine value increased in 6 patients. The duration of operation in the group with complications was significantly higher than that in the group without complications. In patients who underwent an operation lasting ≥ 60 minutes, stone size, fluoroscopy time, and complication rate were significantly higher than in patients who underwent an operation lasting ≤ 60 minutes.

CONCLUSION

Our opinion is to be careful in patients with a solitary kidney with a big stone and we recommend assigning these procedure to experienced hands for not exceeding 60 minutes in one session.

Retrograde intrarenal surgery for a staghorn renal calculus in a patient with solitary kidney and urinary tract deformity: a case report

Staghorn renal calculi are large, branched stones in the kidney that partially or completely fill the renal pelvis and renal calyces. Percutaneous nephrolithotomy (PCNL) is the gold standard treatment for staghorn calculi. However, we report a retrograde intrarenal surgery (RIRS) performed to treat a staghorn calculus in a patient with a solitary kidney and a deformed urinary tract. The 37-year-old male patient presented with right-sided lumbar pain. The computed tomography (CT) scan found a solitary kidney on the right side with an opaque 4.5 cm × 2.4 cm renal stone and grade I hydronephrosis. Additionally, a urinary tract deformity was observed, and it was secondary to the deformity of the pelvis caused by a previous pubis fracture, which significantly increased the risk and the difficulty of intrarenal surgery. A total number of 3 sessions of RIRS were conducted, and the patient was discharged 3 days after each session on average. The postoperative X-ray exam of the third session revealed that the renal stone was completely removed. The patient recovered well without any complications. This case demonstrates that RIRS is a safe and effective treatment of staghorn calculi with the presence of urinary tract deformation. This suggests RIRS may be of particular interest in minimizing the procedure-related damage of a solitary kidney.

The feasibility of one-stage flexible ureteroscopy lithotripsy in solitary kidney patients with 1-3 cm renal stones and risk factors of renal function changes

Purpose

To compare perioperative outcomes and long-term renal function changes between prior stenting (PS) and not prior stenting (NPS) before flexible ureteroscopy lithotripsy (f-URS) for solitary kidney patients.

Methods

Solitary kidney patients with 10–30 mm renal stones were enrolled in this historical control study. Perioperative parameters and complications were compared. Stone-free was defined as the absence of any residual stones on a CT scan. Renal function changes were evaluated by estimated glomerular filtration rate (eGFR) and adjusted for body surface area. A decrease in the eGFR over 20% was identified as ‘deterioration’ in renal function. The follow-up period was at least 6 months. Logistic regression was used to identify risk factors of renal function deterioration.

Results

Of the 76 patients included, 40 cases experienced prior stenting before f-URS. The average stone diameter was 16.8 ± 4.7 mm, ranging from 10.0 to 28.4 mm. Initial SFR was 85.0 and 83.3% in the PS and NPS groups, respectively (p = 0.842), while SFR after the second procedure was 97.5 and 94.4% (p = 0.926). Seven PS and 5 NPS patients developed complications (p = 0.666). At the postoperative 6 months, seven patients showed a deteriorated renal function. Surgical time in minutes was identified as a risk factor for renal function deterioration after the operation (OR = 1.061, 95% CI: 1.015–1.109, p = 0.009, per minute).

Conclusion

It appears that one-stage f-URS without PS could be feasible for 10–30 mm renal stones in solitary kidney patients, and less surgical time might be beneficial to protect renal function.

[Embolization of a false arterial aneurysm in a patient living with one kidney: about a rare complication of percutaneous nephrolithotomy]

La néphrolithotomie percutanée s’accompagne d’un risque de complications en particulier hémorragiques, qui en fait une technique potentiellement invasive. Nous rapportons le cas d’une patiente de 70 ans, traitée auparavant pour néphrolithotomie percutanée d’une lithiase sur un rein unique gauche. Une hématurie persistante de moyenne abondance est apparue il y a 2 mois et demi, et qui a motivé à la réalisation d’une tomodensitométrie découvrant un faux anévrisme intra rénal polaire inférieur, d’origine iatrogène. Il a nécessité une embolisation sélective efficace à la colle biologique.

Endourologic Management (PCNL, URS, SWL) of Stones in Solitary Kidney: A Systematic Review from European Association of Urologists Young Academic Urologists and Uro-Technology Groups

Introduction: Urolithiasis in solitary kidney (SK) presents significant management dilemma as any insult to the kidney or its drainage can lead to significant morbidity. The treatment options include shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PCNL), and ureteroscopy (URS). Our aim was to conduct a systematic review of literature on all available endourologic techniques reporting on the management of stones in an SK. Materials and Methods: We conducted a systematic review according to the Cochrane and PRISMA checklist for all English-language articles from inception to December 2018. All studies with a minimum of 10 patients that reported on endourologic management (SWL, PCNL, or URS) were included. Data were extracted for patient and stone demographics, outcomes including stone-free rate (SFR), adverse events, and renal function. Results: After an initial search of 553 articles, 27 were included for the final review (10 PCNL, 1 mini-PCNL, 9 URS, 1 SWL, and 6 comparative studies). The choice of treatment seemed to be based on stone size, with PCNL, URS, and SWL offered for mean stone sizes between 25-50, 10-28, and 12-15 mm, respectively. PCNL, URS, and SWL were reported in 1445, 792, and 186 patients, respectively, with a final SFR of 67%-97.7%, 43%-100%, and 73%-80% and a complication rate of 26.4%, 15%, and 16.7% across the three groups. The renal function deterioration was reported in 4/16 PCNL studies and in 1/15 URS studies, while it remained unaffected in the SWL study. Conclusions: Our review shows a rise of endourologic techniques in the management of stones in SK. Although PCNL was used for larger stones, it had a higher risk of major complications, including blood transfusion. While a good SFR was obtained for patients irrespective of the treatment modality, the selected intervention needs to be balanced with its safety profile and the need for ancillary procedures.

A new prediction model for operative time of flexible ureteroscopy with lithotripsy for the treatment of renal stones

This study aimed to develop a prediction model for the operative time of flexible ureteroscopy (fURS) for renal stones. We retrospectively evaluated patients with renal stones who had been treated successfully and had stone-free status determined by non-contrast computed tomography (NCCT) 3 months after fURS and holmium laser lithotripsy between December 2009 and September 2014 at a single institute. Correlations between possible factors and the operative time were analyzed using Spearman’s correlation coefficients and a multivariate linear regression model. The P value < 0.1 was used for entry of variables into the model and for keeping the variables in the model. Internal validation was performed using 10,000 bootstrap resamples. Flexible URS was performed in 472 patients, and 316 patients were considered to have stone-free status and were enrolled in this study. Spearman’s correlation coefficients showed a significant positive relationship between the operation time and stone volume (ρ = 0.417, p < 0.001), and between the operation time and maximum Hounsfield units (ρ = 0.323, p < 0.001). A multivariate assessment with forced entry and stepwise selection revealed six factors to predict the operative time of fURS: preoperative stenting, stone volume, maximum Hounsfield unit, surgeon experience, sex, and sheath diameter. Based on this finding, we developed a model to predict operative time of fURS. The coefficient of determination (R²) in this model was 0.319; the mean R² value for the prediction model was 0.320 ± 0.049. To our knowledge, this is the first report of a model for predicting the operative time of fURS treatment of renal stones. The model may be used to reliably predict operative time preoperatively based on patient characteristics and the surgeons’ experience, plan staged URS, and avoid surgical complications.

Percutaneous nephrolithotomy versus retrograde intrarenal surgery for the treatment of kidney stones up to 2 cm in patients with solitary kidney: a single centre experience

BACKGROUND

To compare the treatment outcomes between percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) for the management of stones larger than 2 cm in patients with solitary kidney.

METHODS

One hundred sixteen patients with a solitary kidney who underwent RIRS (n = 56) or PCNL (n = 60) for large renal stones (>2 cm) between Jan 2010 and Nov 2015 have been considered. The patients' characteristics, stone characteristics, operative time, incidence of complications, hospital stay, and stone-free rates (SFR) have been evaluated.

RESULTS

SFRs after one session were 19.6% and 35.7% for RIRS and PCNL respectively (p = 0.047), but the SFR at 3 months follow-up comparable in both groups (82.1% vs. 88.3%, p = 0.346). The calculated mean operative time for RIRS was longer (p < 0.001), but the mean postoperatively hospital stay was statistically significantly shorter (p < 0.001) and average drop in hemoglobin level was less (p = 0.040). PCNL showed a higher complication rate, although this difference was not statistically significant.

CONCLUSIONS

Satisfactory stone clearance can be achieved with multi-session RIRS in the treatment of renal stones larger than 2 cm in patients with solitary kidney. RIRS can be considered as an alternative to PCNL in selected cases.

Percutaneous Nephrolithotomy for Stones in Solitary Kidney: Evidence From a Systematic Review

Stones in solitary kidney represent a management dilemma for the endourologist. The advantage of bilateral fully functioning kidneys is not present. Therefore, any insult to either the solitary kidney itself or drainage system can lead to significant morbidity. Key clinical objectives include maximum preservation of existing renal function, high stone clearance, and minimizing post-procedure complications. To date, there exists no Level 1 evidence on this subject. This systematic review serves to evaluate the safety and efficacy of percutaneous nephrolithomy for patients (adults only) with stones in a solitary kidney.