Surgical management of high-grade vesicoureteral reflux in an 18-month-old female with a solitary kidney: A case report from a resource-limited setting.

Key Clinical Message: Conservative nonsurgical therapy ensures that the resolution is nearly 80% for vesicoureteral reflux grades I and II and 30%-50% for vesicoureteral reflux grades III and V within 4-5 years of follow-up. Open surgical reimplantation of ureters of grades IV and V is a highly successful procedure, with reported correction rates ranging from 95% to 99% regardless of the severity of vesicoureteral reflux. Abstract: Patients with vesicoureteral reflux present with a wide range of severity. With an incidence of approximately 1%, vesicoureteral reflux is a relatively common urological abnormality in children. Postnatal diagnosis of vesicoureteral reflux is typically made following a diagnosis of a urinary tract infection and less frequently following family screening. Voiding cystourethrograms remain the gold standard for diagnosing vesicoureteral reflux. To preserve the kidney and prevent the need for potential renal replacement therapy, infants with a single kidney require significantly more assessments and prompt decision-making. Surgical correction is advised for patients with vesicoureteral reflux grades IV and V, while vesicoureteral reflux grades I, II, and III are managed conservatively.

Renal function after ureteral reconstruction surgery in patients with solitary kidney.

Background: Ureteral strictures (US) could lead to impaired kidney function, which was alleviated by ureteral reconstruction surgery. However, solitary kidney (SK) patients with US were more complicated to treat. This study aimed to evaluate the impact of reconstruction surgery on renal function based on estimated glomerular filtration rate (eGFR) in patients with SK. Methods: We retrospectively enrolled patients who underwent reconstruction surgery between April 2014 to March 2022. eGFR was measured pre- and postoperatively. The 'static renal function' was defined as a change in eGFR of 20% or less at the last follow-up, and the 'worsening renal function group' was defined as a decrease of greater than 20%. Results: A total of 61 SK patients were involved. The success rate of ureteral reconstruction surgery was 90.16% (55/61). The median follow-up time was 20.8 months (range, 3.7-109.2 months). The median eGFR was 65.5 (range, 15.1-99.9) and 65.3 (range, 3.8-123.4) mL/min/1.73 m2 at the baseline and the last follow-up. No statistically significant difference in eGFR was observed between the preoperative baseline and last follow-up visits (P=0.58). However, in patients with baseline renal dysfunction [chronic kidney disease (CKD) stage 3-5], the eGFR significantly improved at the last follow-up compared to the baseline (P=0.02). Three patients developed a 'worsening renal function' (4.92%). Besides, the systolic blood pressures (SBP) at follow-up significantly reduced compared to the preoperative baseline (P=0.002). Conclusions: Ureteral reconstruction surgery is an effective treatment to preserve renal function, which also achieves a high success rate and is associated with the reduction of SBP for SK patients with US.

Correlation of ablation volume with renal function loss after cryoablation in solitary functioning kidneys.

PURPOSE: The purpose of this study was to retrospectively analyze the degree of renal function deterioration after renal cryoablation in patients with a solitary functioning kidney based on ablation volume. MATERIALS AND METHODS: Over a 15-year period, 81 percutaneous cryoablations were performed in solitary functioning kidneys. After exclusion of patients with baseline end-stage renal disease(ESRD) and insufficient follow up, analysis was performed on 65 procedures in 52 patients (40 male, mean age 63.5 years). The post-cryoablation renal function was based on the lowest serum creatinine within 6 months post-procedure. Renal function change was defined as percentage glomerular filtration rate(GFR) change. Volumetric analysis was performed on the target lesion, renal parenchyma, and ablation zone. RESULTS: The median tumor diameter was 2.0cm (range 0.8-4.7cm). The median baseline GFR decreased from 56.4 mL/min/1.73m2 (range 17.5-89.7) to 46.9 (range 16.5-89.7) at median 95 days (p<0.001), equating to an -7.9% median renal function change (range -45.0 to +30.7). All patients had stage 2 or worse chronic kidney disease and baseline function did not correlate with renal function change. The median volume of ablated parenchyma was 19.7mL (range 2.4-87.3mL), equating to 8.1% (range 0.7-37.2%) of total parenchyma. The volume of parenchymal volume ablated correlated significantly with renal function loss, while age, hypertension, and diabetes mellitus did not. No patients developed ESRD within 1 year after cryoablation. CONCLUSION: Cryoablation in solitary functioning kidneys resulted in a modest reduction in renal function, even in patients with chronic kidney disease and ablations up to 20% of renal parenchymal volume.

A novel treatment strategy for bladder hypoplasia: A case of megaureter in a functional solitary kidney.

Introduction: We report a case of megaureter in a functional solitary kidney in which surgery was performed after bladder capacity was increased by home bladder cycling. Case presentation: A 6-day-old girl with a left megaureter, a right multicystic dysplastic kidney, and bladder hypoplasia underwent percutaneous left nephrostomy for obstructive renal failure. At 8 months, home bladder cycling was initiated to increase bladder capacity before the planned ureterocystoneostomy. Surgery was performed after bladder capacity increased. The left ureter was compressed by the left umbilical ligament, so ureteral end-to-end anastomosis was performed at 1 year and 4 months. At 2 years and 8 months, cystometry showed age-appropriate bladder capacity and improved bladder compliance. Conclusion: To the best of our knowledge, this is the first report of bladder hypoplasia treated by home bladder cycling.

Safety and Efficacy of Percutaneous Nephrolithotomy in Solitary Functioning Kidneys: A Retrospective Cohort Study in an Asian Population.

Objective The aim of the study was to assess the safety of preserved renal function after standard percutaneous nephrolithotomy (PCNL) in patients with a single functional kidney. The main parameters to focus on were serum creatinine levels and any associated complications. Materials and methods This retrospective cohort study was conducted in an Eastern population in a single center from 2016 through 2023 at The Kidney Centre Postgraduate Training Institute, Karachi, Pakistan. Results Out of the total 1,550 PCNL procedures performed on adult patients, 47 patients had a solitary functioning kidney with stones, which were evaluated. The stone clearance rate was 95.74% (45 patients), with a mean operative time of 85.96 minutes. Most patients, i.e., 33 (70.21%), had an infracostal approach, and single tract management was sufficient for 45 (95.74%) patients. The most common complication was transfusion, which was required in five (10.64%) patients. Mean preoperative hemoglobin dropped by 1.43mg/dL postoperatively, and mean serum creatinine decreased from 2.45mg/dL to 1.97mg/dL. Among the 24 (51.06%) analyzed stones, all were calcium oxalate. Conclusion In challenging situations such as a solitary kidney with a large stone, PCNL is the procedure of choice. However, the refined technique is of paramount importance. Overall, the use of PCNL in these unique conditions is safe and rewarding.

Early diagnosis of solitary functioning kidney: comparing the prognosis of kidney agenesis and multicystic dysplastic kidney.

BACKGROUND: Individuals with congenital solitary functioning kidney (SFK) are at an increased risk of kidney damage. According to some studies, the risk is higher in unilateral kidney agenesis (UKA) than in unilateral multicystic dysplastic kidney (UMCDK). We hypothesized that with early detection of children with UKA and UMCDK, there would be no difference in the presence of hypertension, proteinuria, and reduced glomerular filtration rate (GFR) between UKA and UMCDK. METHODS: Based on a long-term follow-up protocol, we evaluated a cohort of 160 children followed from birth for SFK (84 with UKA and 76 with UMCDK) detected by prenatal or routine neonatal ultrasound screening. Hypertension, proteinuria, and reduced GFR were monitored as markers of kidney damage. We compared the characteristics and outcomes of the subgroups of children with UKA and UMCDK. RESULTS: GFR was reduced in 42 (26.2%) children, of whom 41 showed only mild reduction. Hypertension and proteinuria were found in 22 (13.8%) and 14 (8.8%) children, respectively. Combined kidney damage was present in 57 (35.6%) children. The UMCDK and UKA subgroups differed in GFR at final examination, with UMCDK patients being significantly more likely to have normal GFR compared to UKA patients (82% vs. 67%; p = 0.039). CONCLUSIONS: One third of the children showed signs of SFK damage, albeit mild. Patients with UKA had reduced GFR significantly more often than those with UMCDK, but did not differ in the rates of hyperfiltration injury or congenital anomalies of the kidneys and urinary tract (CAKUT) in SFK.

Successful coiling embolization of an intraparenchymal renal pseudoaneurysm: Case reports.

INTRODUCTION AND IMPORTANCE: Intraparenchymal renal artery aneurysms are a really rare condition that represents <10 % of all renal artery aneurysms. They are more often caused by trauma or iatrogenic injury and their rupture can lead to life-threatening hemorrhage. CASE PRESENTATION: We report the case of a 25-year-old male with history of back stab wound three months before being admitted to our unity. The patient presented a macroscopic hematuria three days after the injury. An abdominal CT angiography revealed an intraparenchymal renal artery aneurysm, and it was successfully treated with super selective endovascular coil embolization, achieving both pseudoaneurysm exclusion and renal preservation. CLINICAL DISCUSSION: Intraparenchymal renal artery aneurysms are rare. They are more often caused by trauma or iatrogenic injury. Renal artery pseudoaneurysms are mainly asymptomatic. Renal pseudoaneurysms can be diagnosed through contrast enhanced CT, renal Doppler ultrasound, or MRI. Super selective embolization of the feeding artery of the pseudoaneurysm using endovascular techniques is the treatment of choice. CONCLUSION: The management of patients with renal pseudo aneurysms should allow to achieve two main goals: Preserving Renal function, and excluding the pseudoaneurysm.

A Narrative Review of Contact Sports Participation in Children and Young Athletes With a Solitary (Functioning) Kidney.

BACKGROUND: Evidence is sparse regarding the incidence or prevalence of renal or genitourinary injuries arising from contact sports. There are currently no World Health Organization or European consensus guidelines relating to the participation in sport for children and young athletes with a solitary (functioning) kidney. PURPOSE: To review the international literature and to make sport-specific recommendations for children and young athletes with a solitary (functioning) kidney participating in sports, based on the overall likelihood of potential renal or genitourinary injury. STUDY DESIGN: Narrative review; Level of evidence, 4. METHODS: A descriptive epidemiological study was conducted of current literature according to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. Embase, Google Scholar, Cochrane, and PubMed databases were queried from 1975 to 2023, to assess available evidence regarding the prevalence and risk of renal injury through sports participation and guidelines surrounding the participation in sports for children and young athletes with a solitary (functioning) kidney. Methodological quality and certainty of evidence were assessed according to the International Classification of Urological Disease guidelines. RESULTS: A total of 28 publications were identified after database searches and exclusions, comprising 40,889 patients. The majority of papers providing recommendations arose from the United States. Of the recommendations, 79% permitted an unrestricted return to noncontact sports. A return to contact sports is permitted in most instances after physician consultation. CONCLUSION: There is a dearth of good-quality published evidence in the literature relating to sports participation with a solitary (functioning) kidney. Overall, the risk of genitourinary injury in sports is low, and after physician assessment, there is currently no strong evidence to exclude children and young athletes with a solitary (functioning) kidney from full participation in contact and collision sports.

Endoscopic combined intrarenal surgery for successful removal of an encrusted ureteral stent and multiple renal stones in solitary kidney: A case report.

INTRODUCTION AND IMPORTANCE: Several endoscopic procedures have been performed to clear stones in the kidney. A potential technique called endoscopic combined intrarenal surgery (ECIRS) is a practical option for treating complex kidney stones. Hereby, we report a neglected double j (DJ) stent and recurrent multiple kidney stones treated by ECIRS. CASE PRESENTATION: A 56-year-old female complained of right flank pain one week ago, which worsened within one day before hospital admission. She underwent DJ stent insertion one year ago because of residual stones after right percutaneous nephrolitothomy (PCNL) but was lost to follow-up. There was a history of left nephrectomy, leaving the patient with only a right kidney. A x-ray kidney ureter bladder (KUB) evaluation showed multiple irregular radiopaque shadows. A computed tomography (CT) scan detected numerous stones in the right kidney. The patient underwent ECIRS to remove the DJ stent and clear multiple stones in the right kidney. Following the surgery, the patient was discharged from the hospital on the fourth postoperative day with no complications and residual stone. CLINICAL DISCUSSIONS: ECIRS is a technique that combines a simultaneous antero-retrograde approach to the kidney and aims to resolve nephrolithiasis in one step and with one access. The ECIRS procedure could be considered in cases of complex multiple stone nephrolithiasis. ECIRS could widen the operative vision, thus helping to clear difficult kidney stones. CONCLUSIONS: The ECIRS technique could provide successful and safe management of recurrent multiple kidney stones and encrusted, neglected DJ stents in a solitary kidney patient.

Renal Function After CT-Guided Cryoablation of Small Renal Tumours in Patients with Solitary Kidney: An Analysis of European Multinational Prospective EuRECA Registry.

PURPOSE: Treatment of renal cell carcinoma (RCC) in patients with solitary kidneys remains challenging. The purpose of this multicentre cohort study was to explore how renal function is affected by percutaneous image-guided cryoablation in patients with solitary kidneys. MATERIAL AND METHODS: Data from the European Registry for Renal Cryoablation database were extracted on patients with RCC in solitary kidneys treated with image-guided, percutaneous cryoablation. Patients were excluded if they had multiple tumours, had received previous treatment of the tumour, or were treated with more than one cryoablation procedure. Pre- and post-treatment eGFR (within 3 months of the procedure) were compared. RESULTS: Of 222 patients with solitary kidneys entered into the database, a total of 70 patients met inclusion criteria. The mean baseline eGFR was 55.8 ± 16.8 mL/min/1.73 m2, and the mean 3-month post-operative eGFR was 49.6 ± 16.5 mL/min/1.73 m2. Mean eGFR reduction was - 6.2 mL/min/1.73 m2 corresponding to 11.1% (p = 0.01). No patients changed chronic kidney disease group to severe or end-stage chronic kidney disease (stage IV or V). No patients required post-procedure dialysis. CONCLUSION: Image-guided renal cryoablation appears to be safe and effective for renal function preservation in patients with RCC in a solitary kidney. Following cryoablation, all patients had preservation of renal function without the need for dialysis or progression in chronic kidney disease stage despite the statistically significant reduction in eGFR. LEVEL OF EVIDENCE 3: Observational study.

Any reduction in maternal kidney mass makes a difference during pregnancy in gestational and fetal outcome.

Little is known about the effect tubulointerstitial nephropathies have in modulating maternal-fetal outcomes in pregnancy. Therefore, we analyzed the main outcomes of pregnancy in these women to gain a better understanding of the role of a reduction in maternal kidney mass. From the Torino Cagliari Observational Study (TOCOS) cohort, we selected 529 patients with a diagnosis of tubulointerstitial disease and focused on 421 patients with chronic kidney disease (CKD) stage 1, without hypertension but with proteinuria less than 0.5 g/day at referral. From a cohort of 2969 singleton deliveries from low-risk pregnancies followed in the same settings we selected a propensity score matched control cohort of 842 pregnancies match 2:1 for age, parity, body mass index, ethnicity, and origin. Time to delivery was significantly shorter in the study cohort 38.0 (Quartile 1-Quartile 3: 37.0-39.0) versus 39.0 (Q1-Q3 38.0-40.0) weeks, with respect to controls. Incidence of delivery of less than 37 gestational weeks significantly increased from controls (7.4%) to women with previous acute pyelonephritis (10.8%), other tubulointerstitial diseases (9.7%) and was the highest in patients with a single kidney (31.1%). Similarly, neonatal birthweight significantly and progressively decreased from controls (3260 g [Q1-Q3: 2980-3530]), previous acute pyelonephritis (3090 g [Q1-Q3: 2868-3405], other tubulointerstitial diseases (3110 g [Q1-Q3: 2840-3417]), and to solitary kidney (2910 g [Q1-Q3: 2480-3240]). Risk of developing preeclampsia was significantly higher in the CKD cohort (3.6% vs 1.7% in low-risk controls). Thus, even a small reduction in functional kidney mass, such as a pyelonephritic scar, is associated with a shorter duration of pregnancy and an increased risk of preterm delivery. The risk is proportional to the extent of parenchymal reduction and is highest in cases with a solitary kidney.

Perioperative, functional, and oncological outcomes after cryoablation or partial nephrectomy for small renal masses in solitary kidneys: a systematic review and meta-analysis.

AIM: This study aims to compare the perioperative, functional, and oncological outcomes of cryoablation (CA) and partial nephrectomy (PN) for managing small renal masses in patients with solitary kidneys. The study seeks to assess the efficacy and safety of both interventions, evaluating their impact on kidney function and their ability to mitigate cancer recurrence. METHODS: Searches were systematically conducted on PubMed, Scopus, EMBASE, SinoMed, and Google Scholar, identifying seven observational studies. Statistical analysis was performed using Stata v.12.0 and Review Manager version 5.2. Results for dichotomous variables are expressed using odds ratios, and weighted mean differences are used for continuous variables. RESULTS: Our findings revealed that patients undergoing CA experienced significantly shorter operative time (p < 0.0001), reduced estimated blood loss (p < 0.00001), a shorter length of stay (p = 0.0001), and fewer postoperative complications (p = 0.02) compared to those undergoing PN. Although the CA group exhibited a lower transfusion rate (p = 0.69) compared with the PN group, the difference was not statistically significant. The combined data analysis demonstrated a significantly lower increase in serum creatinine levels after surgery in the CA group compared with the PN group (p = 0.003). Similarly, there was a noteworthy decrease in the estimated glomerular filtration rate after surgery in the PN group compared with the CA group (p < 0.0001). While not statistically significant, the CA group showed a lower postoperative dialysis rate (p = 0.11). Regarding oncological outcomes, the analysis revealed no significant differences between CA and PN concerning local recurrence (p = 0.2) and distant metastasis (p = 0.12), respectively. CONCLUSIONS: Our analysis indicates comparable efficacy between PN and CA in controlling tumour recurrence and metastasis. However, CA is associated with superior preservation of renal function, significantly enhanced perioperative outcomes, and fewer postoperative complications. Based on our data, it can be inferred that the scope for applying CA might be expanded to encompass more patients seeking a less invasive treatment option.

Müllerian anomalies in girls with congenital solitary kidney.

BACKGROUND: The prevalence of Müllerian anomalies (MA) among patients with congenital solitary functioning kidney (SFK) is not well defined. A delay in diagnosis of obstructive MA can increase the risk of poor clinical outcomes. This study describes the prevalence of MA in patients with congenital SFK. METHODS: A retrospective review was performed of patients within the Nationwide Children's Hospital system with ICD9 or ICD10 diagnostic codes for congenital SFK defined as either unilateral renal agenesis (URA) or multicystic dysplastic kidney (MCDK) and confirmed by chart review. Patients with complex urogenital pathology were excluded. Renal anomaly, MA, reason for and type of pelvic evaluation, and age of diagnosis of anomalies were evaluated. RESULTS: Congenital SFK occurred in 431 girls due to URA (209) or MCDK (222). Pelvic evaluation, most commonly by ultrasound for evaluation of abdominal pain or dysmenorrhea, occurred in 115 patients leading to MA diagnosis in 60 instances. Among 221 patients ages 10 years and older, 104 underwent pelvic evaluation and 52 were diagnosed with an MA of which 20 were obstructive. Isolated uterine or combined uterine and vaginal anomalies were the most common MA. MA were five-fold more common in patients with URA compared to MCDK. In 75% of patients, the SFK was diagnosed prior to the MA. CONCLUSIONS: The prevalence of MA in patients with congenital SFK was 24% among those age 10 years or older, and 38% were obstructive. This justifies routine screening pelvic ultrasound in girls with congenital SFK to improve early diagnosis.

Thermal Ablation Versus Partial Nephrectomy for cT1 Renal Mass in a Solitary Kidney: A Matched Cohort Comparative Analysis.

BACKGROUND: Nephron-sparing approaches are preferred for renal mass in a solitary kidney (RMSK), with partial nephrectomy (PN) generally prioritized. Thermal ablation (TA) also is an option for small renal masses in this setting; however, comparative functional/survival outcomes are not well-defined. METHODS: A retrospective study of 504 patients (1975-2022) with cT1 RMSK managed with PN (n = 409)/TA (n = 95) with necessary data for analysis was performed. Propensity score was used for matching patients, including age, preoperative glomerular filtration rate (GFR), tumor diameter, R.E.N.A.L. ((R)adius (tumor size as maximal diameter), (E)xophytic/endophytic properties of tumor, (N)earness of tumor deepest portion to collecting system or sinus, (A)nterior (a)/posterior (p) descriptor, and (L)ocation relative to polar lines), and comorbidities. Functional outcomes were compared, and Kaplan-Meier was used to analyze survival. RESULTS: The matched cohort included 132 patients (TA = 66/PN = 66), with median tumor diameter of 2.4 cm, R.E.N.A.L. of 6, and preoperative GFR of 52 ml/min/1.73 m2. Acute kidney injury occurred in 11%/61% in the TA/PN cohorts, respectively (p < 0.01). After recovery, median GFR preserved was 89%/83% for TA/PN, respectively (p = 0.02), and 5-year dialysis-free survival was 96% in both cohorts. Median follow-up was 53 months. Five-year recurrence-free survival (RFS) was 62%/86% in the TA/PN cohorts, respectively (p < 0.01). Five-year local recurrence (LR)-free survival was 74%/95% in the TA/PN cohorts, respectively (p < 0.01). Five-year cancer-specific survival (CSS) was 96%/98% in the TA/PN cohorts, respectively (p = 0.7). Local recurrence was observed in nine of 36 (25%) and five of 30 (17%) patients managed with laparoscopic versus percutaneous TA, respectively. For TA with LR (n = 14), nine patients presented with multifocality and/or cT1b tumors. Twelve LR were managed with salvage TA, and seven remained cancer-free, while five developed systemic recurrence, three with concomitant LR. CONCLUSIONS: Functional outcomes for TA for RMSK were improved compared with PN. Local recurrence was more common after TA and often was associated with the laparoscopic approach, multifocality, and large tumor size. Improved patient selection and greater experience with TA should improve outcomes. Salvage of LR was not always possible. Partial nephrectomy remains the reference standard for RMSK.

Functional recovery after partial nephrectomy in a solitary kidney.

OBJECTIVES: Partial nephrectomy (PN) is the reference standard for renal mass in a solitary kidney (RMSK), although factors determining functional recovery in this setting remain poorly defined. PATIENTS/METHODS: Single center, retrospective analysis of 841 RMSK patients (1975-2022) managed with PN with functional data, including 361/435/45 with cold/warm/zero ischemia, respectively. A total of 155 of these patients also had necessary studies for detailed analysis of parenchymal volume preserved. Acute kidney injury (AKI) was classified by RIFLE (Risk/Injury/Failure/Loss/Endstage). Recovery-from-ischemia (Rec-Ischemia) was defined as glomerular filtration rate (GFR) saved normalized by parenchymal volume saved. Logistic regression identified predictive factors for AKI and predictors of Rec-Ischemia were analyzed by multivariable linear regression. RESULTS: Overall, median preoperative GFR was 56.7 ml/min/1.73m2 and new-baseline and 5-year GFRs were 43.1 and 44.5 ml/min/1.73m2, respectively. Median follow-up was 55 months; 5-year dialysis-free survival was 97%. In the detailed analysis cohort, a primary focus of this study, median warm (n = 70)/cold (n = 85) ischemia times were 25/34 minutes, respectively; and median preoperative, new-baseline and 5-year GFRs were 57.8, 45.0, and 41.7 ml/min/1.73m2, respectively. Functional recovery correlated strongly with parenchymal volume preserved (r = 0.84, p < 0.001). Parenchymal volume loss accounted for 69% of the total median GFR decline associated with PN, leaving only 3 to 4 ml/min/1.73m2 attributed to ischemia and other factors. AKI occurred in 52% of patients and the only independent predictor of AKI was ischemia time. Independent predictors of reduced Rec-Ischemia were increased age, warm ischemia, and AKI. CONCLUSION: The main determinant of functional recovery after PN in RMSK is parenchymal volume preservation. Type/duration of ischemia, AKI, and age also correlated, although altogether their contributions were less impactful. Our findings suggest multiple opportunities for optimizing functional outcomes although preservation of parenchymal volume remains predominant. Long-term function generally remains stable with dialysis only occasionally required.

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.

Neglected ureteral stent in a patient with chronic kidney disease and solitary functioning kidney: case report and review of literature.

Introduction: A ureteral stent is crucial for managing urinary flow obstruction, ureteral reconstructive surgeries, and iatrogenic ureteral injuries. The authors aim to report a case of forgotten double-J stent for 17 years, the longest time reported in literature in a patient with solitary kidney and no typical long-term complications as stones formation and encrustation. Case presentation: A 58-year-old male with chronic kidney disease and solitary left kidney presented with left loin pain. With creatinine higher than baseline (6.2 mg/dl), he reported a neglected double-J stent placed 17 years ago in a different hospital. In addition, non-contrast computed tomography and cystoscopy revealed hydronephrosis, cystitis, and an element of infra-vesical obstruction, evident by high bladder neck. Treatment included left percutaneous nephrostomy, but he was readmitted few weeks later for cystoscopy, ureteroscopy, and a new double-J insertion. Due to worsening renal function, he was readmitted four weeks later for cystoscopic removal of the new double-J stent and Transurethral Resection of the Prostate, after which creatinine returned to baseline. Discussion: Double-J stents are vital in urological procedures, but neglecting their presence can lead to severe complications like encrustations, stone formation, stent fractures, hydronephrosis, infections, and renal function loss. Treatment of long-term complications is difficult and should consider many factors, including the type and severity of associated complications and the patient's preoperative status. Conclusion: Preventing complications from neglected or forgotten double-J stents through patient education and follow-up is crucial, especially in those with solitary functioning kidneys due to the imminent loss of renal function.