Ureteral Stent Research Articles

Biocompatible, biodegradable, and anticancer alginate-quercetin ureteral stent via co-axial extrusion technique.

Ureteral stents (US) are used as interventional medical implants in the treatment and surgery of urinary tract infections (UTIs). This study reported a new formulation of alginate-quercetin (AQ) based US through a co-axial extrusion procedure for the first time to afford a 26cm long US with 3.2×1.7 mm external and internal diameter. The mechanical strength such as tensile strength and compression deformation was evaluated in dry and wet form. The stents were characterized through FESEM, FTIR, and XRD to check their morphology, functional groups, and amorphous or crystalline form-similarly, the hydrophilicity/hydrophilicity was observed on contact angle. All the stent formulations showed no cytotoxic effect in CCK-8 assay against human ureteral smooth muscle cells (HUSMC), and human umbilical vein endothelial cell lines (HUVECs) and are confirmed as biocompatible. Similarly, all the formulations exhibited strong anticancer activity against 786-0 and Caki-1 kidney cancer cell lines in the CCK-8 assay. Furthermore, the stent retains its shape and hollow cavity till day 12 in the artificial urine (AU) and is completely degraded on day 16. No change in the pH of the AU was observed during degradation in the AU solution. The current design shows a fast and reliable casting technique for the US, which will open a new window in the designing and manufacturing of the natural biopolymer-based US.

Comparative Analysis of Percutaneous Nephrostomy and Double J Stenting in Upper Urinary Tract Obstruction with Acute Kidney Injury: A Tertiary Hospital Based Prospective Study

Background: Upper urinary tract obstruction is a serious condition that can lead to significant renal impairment if not managed promptly. Emergency urinary diversion is crucial for alleviating obstruction and preserving renal function. This study investigates various emergency urinary diversion techniques, compares their outcomes, and evaluates factors influencing recovery. Methods: We conducted a prospective study involving 106 patients diagnosed with obstructive uropathy at Jawaharlal Nehru Medical College, Aligarh Muslim University. Patients were classified into upper urinary tract obstruction and lower urinary tract obstruction. 70 patients of the upper urinary tract obstruction cases were further managed by either percutaneous nephrostomy (PCN) or double-J (DJ) ureteral stenting diversion procedures. 68 out of 70 upper urinary tract obstruction underwent either of the two procedures. Clinical, demographic, and laboratory parameters were analysed in such patients, and their outcomes were assessed at one and three months. Results: The study included 68 out of 106 patients with a mean age of 48 years. Most patients presented with acute kidney injury (AKI) and had symptoms of loin pain and haematuria. Both PCN and DJ stenting were equally effective in managing upper tract obstruction, with no significant differences in improvement of the laboratory parameters (e.g. Hemoglobin, Serum Creatinine, estimated Glomerular Filtration Rate, Blood Urea Nitrogen) between the two techniques at one and three months. Associated factor like age was associated with unfavourable outcomes. Conclusion: Emergency urinary diversion via PCN or DJ stenting effectively manages upper urinary tract obstruction, with comparable outcomes. Early intervention and management of underlying conditions are critical for optimal renal recovery and prevent irreversible kidney damage.

Safety of CT-guided percutaneous cryoablation in patients treated for clinical T1 renal cell carcinoma with the need for pre-procedural ureteral stenting: An international cohort study

Safety of CT-guided percutaneous cryoablation in patients treated for clinical T1 renal cell carcinoma with the need for pre-procedural ureteral stenting: An international cohort study

Stent vs Stentless Ileal Conduits After Radical Cystectomy: Is There a Difference in Early Postoperative Outcomes?

Placing ureteral stents at the ureteroileal anastomosis for radical cystectomy with ileal conduit (RCIC) has long been common practice. Recently, some providers have begun omitting stents. We sought to investigate differences in perioperative and 30-day outcomes between patients who underwent RCIC with and without stents placed at the ureteroileal anastomosis. We identified RCICs performed between 2019 and 2021 in the National Surgical Quality Improvement Program database and corresponding Cystectomy-Targeted Participant Use File. Baseline demographics, comorbidities, and operative parameters were compared via Pearson's χ2 and t tests between stented and stentless RCICs. Outcomes of interest, including rates of UTIs, acute kidney injury, renal failure requiring dialysis, ileoileal anastomotic leaks, ureteral obstruction, urinary leak or fistula formation, reoperations, and 30-day hospital readmissions, were compared using Pearson's χ2. All statistical tests were 2-tailed with P < .05 considered significant. A total of 5418 RCICs were identified. Four hundred ninety-eight (9.2%) were stentless. There were no differences in baseline demographics or comorbidities. Significantly fewer stented patients had robotic-assisted operations (23% vs 29%, P < .01). Stented patients had lower rates of urinary leak or fistula formation (3.1% vs 4.8%, P = .04). There was no significant difference in 30-day rates of UTIs, acute kidney injuries, renal failure, ileoileal anastomotic leaks, ureteral obstruction, reoperations, and readmissions. Limitations include retrospective design and lack of longitudinal tracking past 30 days. Stentless patients had noninferior outcomes compared to stented patients in most important 30-day outcomes. Our analysis suggests that stents may not be necessary in ileal conduit urinary diversion procedures.

Comparison of three different scoring systems in predicting success of retrograde intrarenal surgery in kidney stones larger than 20 millimeters.

To evaluate stone free rate (SFR) predictivity of three different scoring systems in patients with kidney stones larger than 20 millimeters undergoing retrograde intrarenal surgery(RİRS). Digital records of a total of 166 patients were reviewed retrospectively. Epidemiological characteristics (age, gender, medical history) of the patients, stone and affected kidney characteristics (size, volume, location, density, opaque, presence of urinary system anomaly, presence of stones in different calyx, number of stones, lower pole stone, renal infundibulopelvic angle (IPA), renal infundibulopelvic length (RIL), hydronephrosis), and operative characteristics (preoperative ureteral stent, operation duration, postoperative residual fragments, hospitalization time and complications were recorded. Each patient was scored separately according to the Resorlu-Unsal Scoring System (RUSS), the modified Seoul National University Renal Stone Complexity (S-ReSC) and R.I.R.S scoring systems based on the stone characteristics seen on CT. All three methods had statistically acceptable sensitivity and specificity values. Sensitivity for R.I.R.S nomogram is 62.3%, specificity is 77.1% (cut-off: 7.5 points, area under the curve (AUC):0.735, p < 0.001), sensitivity for RUSS nomogram is 60.7%, specificity is 77.9% (cut off: 2.5, AUC = 0.749, p < 0.001), sensitivity for the Modified S-ReSC nomogram was determined as 65.6% and specificity as 71.2% (cut off: 2.5, AUC = 0.743, p < 0.001). The residual stone ratio was found to be higher in the presence of lower pole stone. While the cut-off value for IPA was 44.5°, this value was calculated as 24.5mm for RIL. Three scoring systems demonstrate accceptable sensitivity and specificity in predicting stone free rate(SFR) with stones ≥ 20mm. Multivariate analysis highlighted the superiority of the R.I.R.S. scoring system for SFR predictivity. In the presence of lower pole stones, IPA and RIL are important factors in predicting surgical success.

Immune-related adverse events with renal colic as the main manifestation: a case report of sintilimab-induced ureteritis/cystitis treated by ureteral stent and review of the literature

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of systemic cancer therapy. During disinhibiting the antitumor responses of immune system, ICIs may also cause unique immune-related adverse events (irAEs) which could affect any organ. Here, we report a rare case of sintilimab-induced ureteritis/cystitis in a 55-year-old male undergoing neoadjuvant chemo-immunotherapy for gastric cancer. The patient presented with severe renal colic, hematuria, and hydronephrosis. Antibiotic antispasmodic and nonsteroidal anti-inflammatory drug treatment failed to alleviate symptoms. The application of corticosteroid was negated for recent extirpative surgery under plan. Bilateral ureteral stenting effectively resolved the pain and improved renal function. The patient later successfully underwent laparoscopic radical gastrectomy with significant tumor regression in postoperative pathology. This case highlights ureteral stenting as a potential corticosteroid-free treatment option for ICI-induced ureteritis/cystitis.

Initial experience of a novel ureteral silicon-covered metallic mesh stent in malignant ureteric obstruction: a single-center retrospective study

BackgroundThis study aimed to investigate initial experiences and outcomes of a retrograde inserted new silicone-covered metallic ureteric stent (Urexel™) for malignant ureteric obstruction.MethodsWe retrospectively reviewed the medical records for 12 consecutive patients who underwent Urexel™ stent placement for malignant ureteric obstruction from March 2020 to March 2021. The Urexel™ stent is a segmental metallic ureteric stent composed of a nitinol mesh covered with a silicone membrane. We evaluated the clinical outcomes and complications of this new metallic ureteric stent.ResultsThe median age of patients was 61.5 (44–82) years, and the median follow-up was 25.5 (4–37) months. One of the 12 patients underwent bilateral stent insertion, Urexel™ stents were placed in a total of 13 ureteral units. There was no technical failure during stent placement. The median length of obstructions was 9 (1–22) cm. Balloon dilation was necessary in 38.5% (5/13 ureter units) of cases. The 6-month success rate was 83.3%, 1-year success rate was 70%, and estimated success rate was 44.4% at 2-year. Encrustation, migration and hyperplasia were the cause of overall treatment failure in all 6 cases of failure, with median elapsed time to failure of 9.5 (1–30) months. Common complications included persistent pain, acute pyelonephritis, and lower urinary tract symptoms, but they were Clavien-Dindo grade I or II.ConclusionsIn this initial series of novel ureteral silicon-covered metallic mesh stents, Urexel™ provided acceptable success and complication rate in malignant ureteric obstructions.

Robot-Assisted Pyelolithotomy in Pelvic Kidney.

Background/Objectives: Pelvic kidney is a congenital anomaly characterized by the kidney's failure to ascend to its normal anatomical location during early embryonic development. This anomaly complicates traditional surgical approaches for renal calculi due to the kidney's atypical positioning and associated anatomical challenges. We sought to summarize our experience with robotic-assisted pyelolithotomy (RPPK) for pelvic kidney stones. Methods: A retrospective review of patients who underwent RPPK was conducted between 2014 and 2023. Demographic data on stone characteristics, operative details, and postoperative outcomes were analyzed. Results: Four patients (three male; mean age-51.2 years with a range of 45-54; mean BMI-26.6 with a range of 22.3-32.2) underwent RPPK. All had a right-sided pelvic kidney; two had prior failed ureteroscopy. The mean stone diameter was 27.7 mm (range: 17-35); the mean density was 1207.5 HU (range: 905-1500). The mean operative time was 265 min (range: 200-323); the time from incision to closure was 142.2 min (range: 95-225). No ureteral stents or drains were used. Blood loss was negligible. The mean hospital stay was 2.2 days. No immediate complications were recorded. The mean follow-up was 11.75 months (range: 3-30). Conclusions: RPPK is safe and effective for managing pelvic kidney stones. Challenging renal anatomy stone size and density are not obstacles to the robotic approach unlike other fragmentation methods.

Double-J Ureteral Stenting in Obstetrics and Gynecology: Pivotal or Problematic?

Background and Objectives: Double-J stents are urinary catheters that are frequently used in urology. They are now also used in other specialist areas such as obstetrics and gynecology. However, the use of double-J stents is not without side effects. The aim of this review was to highlight the indications and possible adverse effects of the use of these stents in obstetrics and gynecology. Materials and Methods: We analyzed works published after 1995 in the PUBMED, SCOPUS, and Web of Science databases related to the use of double-J stents in obstetrics and gynecology, as well as reported adverse events. We carried out a narrative review of the available literature on this topic. Results: We identified 69 relevant publications that we included in the review. In obstetrics, indications include the treatment of gestational hydronephrosis, some urological conditions during pregnancy, such as obstructive urinary calculi, with or without superinfection, or intraoperative use for cesarean section or hysterectomy after cesarean section, to protect from, or to solve, ureteral lesions. In gynecology, they are used preoperatively or intraoperatively to protect the ureter during gynecological operations in the pelvic area or postoperatively to repair some ureteral injuries. They are also indicated for ureteral obstructions that occur after pelvic radiotherapy for gynecological neoplasms. Complications associated with the use of double-J stents include more frequent urinary tract infections, lower urinary tract symptoms, calcifications and misplacements. Conclusions: Double-J stents are widely used in obstetrics and gynecology and are characterized by good efficiency and safety, although some side effects may occur (lower urinary tract symptoms, hematuria, complications in birth outcomes), which do not limit their use. Summary of evidence: In this review, we analyzed the indications and complications of double-J ureteral stenting in obstetric and gynecologic patients. We found that the procedure is safe, both in the treatment of ureteral obstruction and in the resolution of postoperative complications. No serious complications of ureteral stenting have been noted that would constitute a contraindication to its use. Future prospective studies in large patient cohorts are necessary to validate our data.

The effect of training given to patients who underwent ureteroscopy with double-J stent placement on anxiety before and after surgery and readiness for discharge.

Patient education is effective in reducing the level of anxiety before and after surgery and increasing the level of readiness for discharge. Patient education provided by nurses can be planned and applied individually. Therefore, this study aims to determine the effect of the education in whom a double J stent after ureteroscopy on their pre- and postoperative anxiety and levels of readiness for discharge. This research study is a randomized controlled trial with control and intervention groups, pre- and posttests. This study was conducted between November 2021 and May 2022 in a university hospital in Turkey. The patients were divided at random into two groups, control (n = 61) and intervention (n = 61). The Personal Information Form, State-Trait Anxiety Inventory (STAI-I, STAI-II), Surgery-Specific Anxiety Scale (SSAS), Readiness for Hospital Discharge Scale for Adult Patients-Short Form (RHDS/SF) and Readiness for Hospital Discharge Scale- Adult-Nurse Assesment Short Form (RN-RHDS/SF) were used to collect the data. The mean SSAS and STAI-I scores on the morning of surgery and before discharge were found to be significantly lower in the intervention group than the control group. The mean RHDS/SF and RN-RHDS/SF scores on the before discharge were found to be significantly higher in the intervention group than the control group. It was concluded that the education provided to the patients in whom a double J stent after ureteroscopy reduced pre- and postoperative anxiety and increased the level of readiness for discharge.

Perioperative Complications and Omission of Ureteral Stents During Robot-Assisted Radical Cystectomy With Intracorporeal Ileal Conduit.

Ureteral stents are commonly placed intraoperatively during radical cystectomy, although their efficacy in reducing complications is unproven. We compared clinical outcomes among patients undergoing robot-assisted radical cystectomy with intracorporeal ileal conduit (RARC-IC) with or without ureteral stents to determine if omission of ureteral stents affects postoperative complications. All RARC-IC surgeries performed at our institution between November 2017 and June 2023 were reviewed. Beginning August 2021, ureteral stents were routinely omitted. Primary outcome was ureteroenteric anastomosis complications (urine leak, UTI, abscess, and/or sepsis) within 30 and 90 days of RARC-IC. Secondary outcomes included rates of wound infections, urgent care center visits, inpatient readmissions, and ureteral stricture. Among 133 patients included, 90 patients (68%) received a ureteral stent and 43 (32%) did not. Composite ureteroenteric anastomosis complications were higher in the stented group (20% vs 9.5%, 10% difference, 95% CI, -3.4% to 24%, P = .2), though not statistically significant. The stented group had a significantly higher 30-day UTI rate (19% difference, 95% CI, 9.0%-29%, P = .007). The 30-day readmission rates were higher in the stented group, although differences did not meet statistical significance (19% vs 9.8%, 9.1% difference, 95% CI, -4.8% to 23%, P = .3). Limitations include lack of randomization and inability to evaluate some outcomes, including ureteral obstruction or strictures. Omission of ureteral stent placement at RARC-IC is safe and feasible. Randomized trials are warranted to determine the effects of stents on risk of postoperative complications after RARC-IC.

Comprehensive analysis of the bacterial spectrum for enhanced clinical insight in microbial ureteral stent colonization, uncomplicated urinary tract infections and catheter-associated urinary tract infections: a principal component analysis-based literature review

PurposeControversies exist regarding the prevailing spectrum of microorganisms in microbial ureteral stent colonization (MUSC) and their clinical significance. The aim of this comprehensive review is to determine the predominant microbial spectrum in patients with an indwelling ureteral stent in comparison to catheter-associated urinary tract infections (CAUTI) and uncomplicated urinary tract infections (UTI).MethodsGoogle scholar, PubMed, Embase, Medline, and Cochrane literature databases were searched from inception to April 2022 to identify manuscripts on MUSC, uncomplicated UTI and CAUTI. A principal component analysis (PCA) was performed to identify patterns of the pathogen spectrum of the different groups.ResultsWe included 29 studies on MUSC, 28 studies on uncomplicated UTI and 23 CAUTI studies. The proportion of Staphylococci, Enterococci and Candida were significantly higher in MUSC and stent associated bacteriuria compared to their proportion in uncomplicated UTIs where E. coli dominates. By comparing MUSC, CAUTI and UTI with a PCA, the detected pathogen spectrum exhibited clearly distinguishable trends in the frequency of the main isolated pathogens influencing these three groups of urinary tract infections. With respect to MUSC and UTI, their 95% confidence interval ellipse only showed minimal overlap emphasizing that the spectrum of pathogens in the two groups is clearly distinct.ConclusionsThe frequency of detection of Staphylococci, Enterococci and Candida is more common in MUSC as compared to UTI. Thus, patients with indwelling ureteral stents should undergo an antimicrobial prophylaxis targeting this microbial spectrum in case of further surgery.

An analysis of renal and surgical outcomes of patients with and without preoperative ureteral stenting before Nephron-Sparing Surgery for renal malignancies of higher complexity by using a propensity score-based approach.

This study aims to evaluate the impact of preoperative ureteral stenting on postoperative outcomes, especially the incidence of urinoma, in patients with complex renal tumors undergoing nephron-sparing surgery. A retrospective analysis of 35 patients who received preoperative ureteral stenting prior to nephron-sparing surgery for complex tumors at the University Hospital of Würzburg between 2002 and 2021. A control group of 115 patients was established through 1:3 propensity score matching based on age, gender, T-stage, and RENAL score. Clinical parameters, surgical outcomes, and complications were assessed, and statistical comparisons were performed using the unpaired Student's t-test and chi-square test. While both groups showed comparable tumor complexity (RENAL: 7 vs 7, p=0.58; PADUA: 9 vs 8, p=0.62), there were no significant differences in median hospital stay (12 vs. 11; p=0.068), surgical time (183 vs. 190 minutes; p=0.37), postoperative haemoglobin levels (11g/dl vs. 11.1d/dl; p=0.9) and renal function (GFR 65 ml/min/m² in both groups). Moreover complication severity during NSS, defined by Clavien-Dindo classification, was similar (none vs. grade I; p=0.29). No significant difference in the rate of urinoma was observed (11% vs. 4%, p=0.93). This study found no significant benefits of preoperative ipsilateral ureteral stenting on postoperative outcomes, particularly concerning the development of urinoma. Given these findings, preventive ureteral stenting is not recommended prior to partial kidney resection for complex renal tumors.

Development of Prediction Models for Severe Pain and Urinary Symptoms after Ureteroscopy with Ureteral Stent Placement: Results from the STENTS Study and Initial Validation of Pain Interference.

We developed prediction models for severe pain and urinary symptoms after ureteroscopy with ureteral stent placement. The development cohort included 424 adults and adolescents enrolled in the multicenter STENTS prospective cohort study who underwent ureteroscopy with stent placement for urinary stones. The validation cohort was an independent prospective cohort of 115 adults. The outcomes were severe pain intensity and pain interference, measured by PROMIS, and severe urinary symptoms, measured by the Ureteral Stent Symptom Questionnaire. The top quartile of symptoms on postoperative days 1 and 3 were defined as severe. Generalized estimating equation models were used to predict severe symptoms on postoperative days 1, 3, 5, and 7-9 in the development cohort and severe pain interference on days 1 and 7 in the validation cohort. Female sex, younger age, higher body mass index, baseline pain interference and number of chronic pain conditions, renal stone location, and history of anxiety predicted severe pain. In the development cohort, the C-statistics were 0.83 (95% CI 0.80-0.85) for severe pain interference and 0.82 (95% CI 0.79-0.84) for severe pain intensity. A model in which baseline urinary symptoms replaced pain interference had excellent discrimination for severe urinary symptoms (C-statistic 0.83; 95% CI 0.81-0.85). In the validation cohort, the C-statistic was 0.7 for severe pain interference (95% CI 0.54-0.78). Preoperative characteristics accurately predicted severe pain and urinary symptoms after ureteroscopy with stent placement. Upon further validation, these models could guide clinical decisions to improve surgical outcomes.

Efficacy and Safety of Two Different Approaches in the Drainage of the Upper Urinary Tract in "Acute Obstructive Uropathy": A Critical Evaluation.

Aim: To compare the results of retrograde ureteral stent (RUS) and percutaneous nephrostomy (PCN) procedures for decompression in patients with acute obstructive pyelonephritis. Patients and Methods: Medical records of patients undergoing PCN or RUS for emergency urinary diversion because of obstructive pyelonephritis were evaluated retrospectively. Patients with urinary tract obstruction and concurrent fever (≥38°C), pyuria, and costovertebral angle tenderness were included and divided into two groups based on the type of emergency urinary drainage applied (PCN in Group 1) and (RUS in Group 2). Apart from the demographic data and Charlson Comorbidity Index, laboratory and radiologic examination outcomes were well evaluated. Results: A total of 155 patients including 73 patients (47.1%) undergoing PCN (Group 1) and 82 patients (52.9%) undergoing RUS (Group 2). Although no significant difference was found regarding the demographic characteristics, the operation time, as well as fluoroscopy time, was significantly shorter in Group 1 cases when compared with those in Group 2 (p < 0.0001). The success rate was similar between the two groups, and there was also a significant difference regarding the complication rates in both groups of cases (5.5% vs 7.3%). Conclusions: Our findings showed that despite similar efficacy and success rates noted between PCN and RUS applications in the emergency drainage of cases presenting with obstructive pyelonephritis, PCN application was found to be advantageous because of shorter operation and fluoroscopy durations. More importantly, this approach was associated with a significantly less need for intensive care during the postoperative period.

Does coiling of the proximal end of the ureteral stent affect stent-related symptoms?

To evaluate the impact of coiling of the proximal end of the ureteral stent on stent-related symptoms (SRS) in in subgroup of patients undergoing preoperative ureteral stenting preceding flexible retrograde intrarenal surgery (RIRS). We performed a prospective comparative study including patients undergoing stent placement 7-10 days prior to RIRS. Patients were divided into 2 groups; in Group 1 coiling of proximal end of the DJ was present, while in Group 2 coiling was absent. Bladder pain, flank pain, hematuria, urgency, frequency, nocturia, and urge incontinence were evaluated on the day of surgery using Visual Analog Score (VAS). In total, 81 patients, 45 males (55.6%) and 36 (44.4%) females were included. Patients in Group 2 had statistically significant severe representation of flank (43.2% vs. 22.7%, p-value = 0.049) and bladder pain compared to Group 1 (48.4% vs. 25.0%, p-value = 0.027). Additionally, they required analgesic medications more frequently (64.9% vs. 34.1%, p-value = 0.006), and experienced significantly more pronounced frequency (p-value = 0.012) and urgency (2.7 vs. 2.1, p-value = 0.033) compared to Group 1. Patients in group 1 recovered from their symptoms more frequently (52.3% vs. 29.7%, p-value = 0.041), occurring on day 4 and 5 following ureteral stenting. Coiling of the proximal end of the DJ stent impacts stent-related symptoms significantly. Better outcomes of post-procedural frequency, urgency, bladder and flank pain were observed in patients in whom coiling was achieved. Moreover, those patients reported faster recovery from SRSs.

Robotic lower-lip mucosal graft ureteroplasty for ureteral stenosis longer than 2 cm: initial experience of thirteen patients.

To present our initial experience of robotic ureteroplasty with lower-lip mucosal graft (LLMG) for treating ureteral stenosis longer than 2 cm and evaluate its feasibility and efficacy. A total of thirteen patients with ureteral stenosis who underwent robotic ureteroplasty with LLMG were retrospectively analyzed. After identification and dissection of the ureteral stenosis segment, the segment was incised longitudinally. Then, the LLMG was harvested according to the characteristics of stenosis and sutured with the ureter in onlay fashion. All procedures were completed successfully. The median stenosis length was 3.5 cm (ranged: 3.0-4.5 cm). The mean length and width of the LLMG were 3.81 ± 0.60 cm and 1.27 ± 0.26 cm, respectively. The mean operative time and anastomosis time were 212.31 ± 23.06 min and 36.54 ± 6.58 min, respectively. The double-J stent was removed at 8 weeks postoperatively in all patients. Three patients (23.1%) suffered postoperative complications during the follow-up period (range, 6-18 months), including fever, urinary tract infection and stenosis recurrence. The success rate was 92.3% (12/13). Robotic ureteroplasty with LLMG is a safe and feasible technique for treating ureteral stenosis.

Flexible Ureteroscopy Combined with Novel Ultra-Flexible Ureteral Access Sheaths for Treating Allium Stent Encrustation: Initial Experience with 15 Cases.

Introduction: Encrustation significantly affects the lifespan of Allium stents. Currently, there is no established treatment for Allium ureteral stent encrustation. This study introduces a method for treating these encrustations using a flexible ureteroscopy (F-URS) combined with a novel ultra-flexible ureteral access sheath (UF-UAS). Methods: We retrospectively analyzed patients treated for Allium stent encrustation with UF-UAS from January 2022 to January 2024. Patients with transplanted kidneys were excluded. The UF-UAS features a 10 cm ultra-flexible distal segment, allowing passive deflection beyond 270° during F-URS. This segment, devoid of wire reinforcement, is made of a silicone composite for optimal pliability. The primary endpoints focused on complications such as damage and migration of the Allium stent. Results: A total of 15 consecutive patients (4 men) underwent the procedure. The cohort included 3, 9, and 3 patients with Allium stents measuring 6, 8, and 10 cm, respectively. Mean preoperative stent dwell time was 19.9 months. Preoperative urine cultures were positive in seven patients. Mean operative time was 33.8 minutes. Three patients (20.0%) required a Double-J stent postoperatively. No instances of Allium stent damage were observed. One patient with ≤2 mm fragments and one patient with 2.1-4 mm fragments within the renal. One patient experienced a 1.5 cm Allium migration one day postoperatively. At 3 months, no Allium migration and increased hydronephrosis were observed. Conclusions: The novel UF-UAS facilitated the effective and safe removal of stones, encrustations, and biofilms from Allium ureteral stents. This method may extend the stent lifespan and reduce the need for stent exchanges.

Emergency treatment of obstructive pyelonephritis: A single center series.

This study aims to compare two different drainage methods, percutaneous nephrostomy (PCN) and retrograde ureteral double-J (DJ) stent insertion, in patients with obstructive pyelonephritis (OP). The study included 77 patients who presented to the emergency department due to stones. Type of decompression treatment (PCN or DJ stent), fever, white blood cell count (WBC), C-reactive protein (CRP) levels, urine culture, blood culture, presence of additional diseases, and antibiotic treatment were evaluated for these patients. Emergency decompressive treatment was not randomly assigned. The clinician chose the appropriate treatment method based on the patient's condition after obtaining an informed consent. Patients under the age of 18 were categorized into three subgroups: infants, children under 10 years, and adolescents. Of the 77 patients, 31 were in the DJ stent group and 46 were in the PCN group. Patients in the PCN group exhibited significantly higher fever levels before the procedure (37.6 ± 1.0°C). Additionally, the positivity rate of urine and blood cultures was higher in the PCN group. The average time to stone treatment after infection and medical treatment, as well as fever control, was shorter in the PCN group (9 ± 2.3 days). Empiric treatment with Ceftriaxone (1 g IV) was confirmed by sensitivity results of urine or blood culture in 45% of cases. None of the patients developed advanced urosepsis after the procedure, but the resolution of infection parameters was faster in the PCN group (7 ± 3.3 days). Both PCN and DJ stent insertion are effective and safe methods for managing obstructive pyelonephritis. It was observed that the PCN method under local anesthesia was useful in quickly controlling fever and allowing early surgical treatment. Finally, third-generation cephalosporin antibiotics are beneficial for empiric initial treatment.

A forgotten double J stent with encrustation leading to pelvi-ureteric obstruction: A case report

Double J (DJ) ureteric stents are widely applied in urological operations, they maintain patient’s urinary system postoperatively, thereby accelerating recovery. Prolonged stent insertion is associated with complications. A 38-year-old woman presented with hematuria, right flank pain, and urinary tract infection. She underwent renal calculi removal 8 years ago. KUB radiograph revealed and indwelling DJ stent with vesical calculus and pyelonephritis. Ultrasound revealed a large bladder stone with mild right hydronephrosis. Computed tomographic (CT) urography revealed a DJ stent encrustation and further formation into core of the bladder stone. Cystolithotomy was performed, vesicle calculi retrieved. At 4 weeks, the patient presented with a right-side flank pain for which patient was evaluated with a contrast-enhanced CT urography which revealed a pelvi-ureteric junction obstruction with hydronephrosis. A pyeloplasty was performed and DJ stent was placed in situ, to be retrieved at 6 weeks. With improved biomaterials, design and technological improvements of DJ stents, patient’s discomfort is greatly reduced. As a result, DJ stents got left in place for a longer duration of time, and therefore high incidences of forgetfulness, retained DJ stents. Encrustation, however, is frequently encountered. Patient factors such as low education and socioeconomic status and patients living in far off rural places also contribute to forgotten indwelling stents. Authors recommend placement of DJ stents after pyeloplasty for treating pelvi-ureteric junction obstructions following long-term retained stents. Patient counseling, education, and strict follow-up should ensure a timely stent removal and improved patient safety. Effective patient counseling and awareness reduces incidences of forgotten indwelling stents and patient-related complications.