Bridging the knowledge gap: past, present and future of antibiotic use for ureteral stents.

OBJECTIVE: To evaluate the available literature on ureteric stent-related infections, the use of antibiotics and bacterial colonisation to identify the current incidence of stent-related infections, unveil knowledge gaps and generate potential hypotheses for future research. METHODS: A literature review was conducted using PubMed, Cochrane and urological association websites identifying relevant English literature published between 1983 and January 2024. RESULTS: There is a worldwide lack of guidelines for antibiotic prophylaxis for stent placement, exchange or extraction. In patients with a negative preoperative urine culture undergoing ureteroscopy and stent placement, it may be considered to only provide prophylaxis in presence of risk factors. However, in pre-stented patients a preoperative urine culture is important to guide prophylaxis during endourological surgery. During stent indwell time, antibiotic prophylaxis does not show any advantage in preventing urinary tract infections (UTIs). There is no strong evidence to support the use of antibiotics at time of stent removal. In the absence of any clear evidence, management strategies for treating UTIs in patients with ureteric stents vary widely. Stent exchange could be considered to remove the biofilm as a potential source of bacteria. Stent culture can help to guide treatment during infection as urine culture and stent culture can differ. CONCLUSION: In terms of good antibiotic stewardship, urologists should be aware that unnecessary use of antibiotics provokes bacterial resistance. There is a great need for further research in the field of antibiotic prophylaxis and stent-related infections to develop evidence that can help shape clear guidelines for this very common urological practice.

Human in vivo baseline intrarenal pressure, peristaltic activity and response to ureteric stenting.

OBJECTIVES: To assess human in vivo intrarenal pressure (IRP) and peristaltic activity at baseline and after ureteric stent placement, using a narrow calibre pressure guidewire placed retrogradely in the renal pelvis. PATIENTS AND METHODS: A prospective, multi-institutional study recruiting consenting patients undergoing ureteroscopy was designed with ethical approval. Prior to ureteroscopy, the urinary bladder was emptied and the COMET™ II pressure guidewire (Boston Scientific) was advanced retrogradely via the ureteric orifice to the renal pelvis. Baseline IRPs were recorded for 1-2 min. At procedure completion, following ureteric stent insertion, IRPs were recorded for another 1-2 min. Statistical analysis of mean baseline IRP, peristaltic waveforms and frequency of peristaltic contractions was performed, thereby analysing the influence of patient variables and ureteric stenting. RESULTS: A total of 100 patients were included. Baseline mean (±SD) IRP was 16.76 (6.4) mmHg in the renal pelvis, with maximum peristaltic IRP peaks reaching a mean (SD) of 25.75 (17.9) mmHg. Peristaltic activity generally occurred in a rhythmic, coordinated fashion, with a mean (SD) interval of 5.63 (3.08) s between peaks. On univariate analysis, higher baseline IRP was observed with male sex, preoperative hydronephrosis, and preoperative ureteric stenting. On linear regression, male sex was no longer statistically significant, whilst the latter two variables remained significant (P = 0.004; P < 0.001). The mean (SD) baseline IRP in the non-hydronephrotic, unstented cohort was 14.19 (4.39) mmHg. Age, α-blockers and calcium channel blockers did not significantly influence IRP, and no measured variables influenced peristaltic activity. Immediately after ureteric stent insertion, IRP decreased (mean [SD] 15.18 [5.28] vs 16.76 [6.4] mmHg, P = 0.004), whilst peristaltic activity was maintained. CONCLUSIONS: Human in vivo mean (SD) baseline IRP is 14.19 (4.39) mmHg in normal kidneys and increases with both hydronephrosis and preoperative ureteric stenting. Mean (SD) peristaltic peak IRP values of 25.75 (17.9) mmHg are reached in the renal pelvis every 3-7 s and maintained in the early post-stent period.

Reducing candidaemia risk in urology patients: Revised algorithm & Pharmacist-Led Implementation.

BACKGROUND: Candidaemia is an invasive infection with high morbidity and mortality. All urology procedures carry risk of post-operative infection. Risk mitigation strategies include preoperative urine culture and treatment of cultured organism(s) regardless of symptoms. After zero cases of candidaemia for two years, there were five cases in elective urology patients within 15 weeks between June September 2021. This increased incidence of candidaemia amongst these patients prompted multidisciplinary investigation. METHODS: Single centre case series, in a 250-bed hospital which annually performs 2000-2500 elective urology surgeries. Affected patients were elderly with multiple comorbidities. Notably, four of five patients had prior indwelling ureteral stents. All five patients had preoperative bacteriuria requiring antibiotics and one patient had pre-operative candiduria. RESULTS: Hypotheses including sterilisation failure, surgical instrument contamination, or surgical technique issues were unfounded. We propose that pre-operative duration of antibacterial therapy, particularly in the setting of ureteral stent biofilm, is a significant factor for candiduria. A new prescribing algorithm for urology patients was devised. Antibiotic treatment duration in asymptomatic patients with indwelling urinary tract foreign material was reduced from 14 to 3 days, and from 14 to 7 days in symptomatic patients. Dedicated pharmacist resources were allocated to support this change and pre-operatively manage these patients. These interventions led to zero candidaemia cases over the subsequent 21 months, along with zero post-operative bacterial bloodstream infections. CONCLUSIONS: Prolonged pre-operative antibacterial therapy poses a risk for post-operative candidaemia, especially in patients with ureteral stents. Shortening pre-operative antibiotic courses, coupled with increased pharmacist involvement, effectively reduced candidaemia incidence.

Navigating the Complexities of Symptomatic Hydronephrosis in Pregnancy.

The management of symptomatic hydronephrosis presents substantial challenges due to the absence of consensus within clinical guidelines concerning pain management, diagnostic approaches, therapeutic interventions, and follow-up protocols. This literature review focuses on complexities involving diagnostic challenges that arise from the difficulty in distinguishing physiological from pathological obstruction and treatment complexities that involve deciding on the most appropriate pain management medications and safe interventions while minimizing risks to both the mother and foetus. To address these challenges, a comprehensive search of electronic databases, including PubMed, Embase, and Google Scholar, was conducted for the terms "hydronephrosis", "hydronephrosis in pregnancy", "ionising radiation in pregnancy", and "safe analgesia in pregnancy". Moreover, Mendeley software was used to collect and organize the references. Diagnostic complexities involve selecting the appropriate imaging modality that balances accurate diagnosis with minimal radiation to the foetus. Ultrasound remains the first-line option. However, it has limitations in delineating the underlying aetiology. MRI avoids ionizing radiation but has restricted utility due to foetal movement artifacts. CT provides the highest diagnostic accuracy but raises foetal radiation exposure concerns, though ultra-low dose protocols (<1 mGy) are deemed acceptable by most guidelines. Management includes either a conservative approach, which is a safe option in the majority of cases, or intervention with a percutaneous nephrostomy or ureteric stent insertion, both with comparable symptom control. However, there is no consensus on the optimal frequency for drain changes to prevent rapid encrustation. Definitive procedures like ureteroscopy and percutaneous nephrolithotomies remain controversial. Most guidelines suggest limiting these interventions to specialist centres during the second trimester if required.

Malignant upper urinary tract obstruction in cancer patients: A systematic review.

Objective: To systematically summarise the current clinical evidence for de novo malignant upper urinary tract obstruction treatment with a focus on standards of reporting, patient outcomes and future research needs. Methods: This review protocol was published via PROSPERO (CRD42022341588). OVID MEDLINE (R), EMBASE, Cochrane Central Register of Controlled Trials-CENTRAL were searched up to June 2022 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses. Prospective and retrospective studies were included. Results: Of 941 articles identified, 82 with 8796 patients were eligible for inclusion.Most studies in the published literature are retrospective and investigate heterogenous malignancies. Percutaneous nephrostomy and ureteric stenting are the most studied interventions. Few studies describe the outcomes from no intervention or investigate patient perspectives. Overall reported median survival after intervention was around 11.7 months. A lack of standardised reporting of outcomes was evident. Conclusions: Malignant upper urinary tract obstruction is an important clinical condition affecting patients globally. Overall survival after intervention appears poor however the current evidence base has significant limitations due to studies of low methodological quality and the lack of a standardised framework for reporting outcomes.We have provided a pragmatic framework for future studies based on the review to ensure a uniform methodology is utilised moving forward.

A case of post-renal acute kidney injury caused by bilateral ureterolithiasis.

Key Clinical Message: Bilateral ureterolithiasis is rare but can cause acute kidney injury (AKI). Clinicians should first examine for post-renal causes of AKI, even if the patient lacks subjective symptoms. Abstract: This letter describes a case of bilateral ureterolithiasis which presented with post-renal acute kidney injury (AKI) and was successfully treated by bilateral retrograde ureteric stenting. Clinicians should be aware of post-renal AKI caused by bilateral ureterolithiasis when acute worsening of renal function with oliguria is observed.

In vitro and in vivo study of antibacterial and anti-encrustation coating on ureteric stents.

OBJECTIVES: To investigate the ability of propolis-coated ureteric stents to solve complications, especially urinary tract infections (UTIs) and crusting, in patients with long-term indwelling ureteric stents through antimicrobial and anti-calculus activities. MATERIALS AND METHODS: Polyurethane (PU) ureteric stents were immersed in the ethanol extract of propolis (EEP), a well-known antimicrobial honeybee product, and subjected to chemical, hydrophilic, and seismic tests. The antimicrobial activity of the EEP coating was then examined by in vitro investigation. Proteus mirabilis infection was induced in rats within uncoated and EEP-coated groups, and the infection, stone formation, and inflammation were monitored at various time points. RESULTS: The characterisation results showed that the hydrophilicity and stability of the EEP surface improved. In vitro tests revealed that the EEP coating was biocompatible, could eliminate >90% of bacteria biofilms attached to the stent and could maintain bacteriostatic properties for up to 3 months. The in vivo experiment revealed that the EEP-coating significantly reduced the amount of bacteria, stones, and salt deposits on the surface of the ureteric stents and decreased inflammation in the host tissue. CONCLUSIONS: Compared with clinically used PU stents, EEP-coated ureteric stents could better mitigate infections and prevent encrustation. Thus, this study demonstrated that propolis is a promising natural dressing material for ureteric stents.

Malignant ureteral obstruction: comparison of metallic, 8 French and 6 French ureteric stents after failure of initial ureteric stent.

PURPOSE: Malignant ureteric obstruction is a significant management challenge. The failure of ureteric stents often leads to long-term nephrostomy tubes. This is delayed for as long as possible due to its' associated morbidity. Several types of ureteric stents are available, however there is little evidence demonstrating which stents are better for preventing progression to nephrostomy tubes. This study looked to determine whether a new 6 French (Fr) polymer stent, 8Fr polymer stent or metallic stent achieved a longer functional duration once the initial polymer ureteric stent failed. METHODS: A retrospective, longitudinal study was performed at a single tertiary institution. All patients who underwent ureteric stenting with a 6Fr polymer stent for malignancy between 2010 and 2020 were included. Patients were followed up until death with ureteric stent in situ or permanent nephrostomy tube insertion. RESULTS: A total of 46 patients (66 ureters) had ureteric stents inserted for malignancy. From initial ureteric stent failure, 10 stents were changed to a new 6Fr polymer stent, 42 were changed to an 8Fr polymer stent and 14 were changed to a Resonance® 6Fr metallic stent. The Resonance 6Fr metallic stent had the longest median functional duration of 14 months (p = 0.012). CONCLUSION: Resonance® 6Fr metallic stents appear to have a significantly longer functional duration than a new 6Fr polymer stent or 8Fr polymer stent, which may allow patients to enjoy a better quality of life and delay permanent nephrostomy tube insertion.

The Management of Symptomatic Hydronephrosis in Pregnancy.

The aim of this article is to provide a literature review on the management of symptomatic physiological hydronephrosis in pregnancy and compare different modalities of intervention when needed. In this review, we conducted an electronic literature search of peer-reviewed journal articles. The PubMed, Research Gate, and Google Scholar databases were queried with the following search terms: "pregnancy", "obstruction," and "hydronephrosis"; the terms "urolithiasis" and "kidney stone" were excluded. As a result, conservative treatment was successful and more favored for most of the patients and the clinicians in the different studies we found. Conservative management will usually include regular analgesia, positioning, and antibiotics. Close follow-up with ultrasound is always recommended. Intervention with ureteric stent insertion or nephrostomy tube insertion was less favored and only triggered by certain clinical criteria. In conclusion, symptomatic hydronephrosis in pregnancy can be safely treated conservatively. However, ureteral double-J stenting or percutaneous nephrostomy are effective and safe treatment methods in the minority of patients with persistent symptoms not responding to conservative management.

Does pre-stenting influence outcomes of shockwave lithotripsy? A systematic review and meta-analysis.

OBJECTIVE: To determine whether preoperative use of JJ stents in patients undergoing shockwave lithotripsy (SWL) impacts on stone clearance and the rate of postoperative complications. PATIENTS AND METHODS: We screened multiple databases from inception to January 2021, using the relevant search terms for SWL in patients with a preoperative stent. Inclusion criteria were randomised controlled trials of ≥20 patients aged >18 years who had had SWL with a JJ stent. This review has been registered in the International Prospective Register of Systematic Reviews (PROSPERO; registration number CRD42023443195). Statistical analysis was performed using 'meta' in R. RESULTS: There were seven eligible studies (403 patients receiving JJ stents and 394 controls). There was no significant difference in the stone-free rate (SFR) following SWL with a JJ stent compared to SWL alone. When considering the complication rates, there was a significantly reduced risk of steinstrasse in patients with a JJ stent. However, there was no significant difference in the risk of other complications including pain, fever, and haematuria, and no significant difference in the likelihood of requiring auxiliary procedures or re-treatment. CONCLUSIONS: There was a reduced risk of steinstrasse in patients undergoing SWL with a JJ stent compared to SWL alone. However, there was no significant difference in the risk of other postoperative complications. Use of a JJ stent had no effect on the efficacy of SWL, with no significant difference in the SFR.

Implementing routine use of self-removed ureteric stents on extraction strings: prospective patient-reported outcome measures and complications.

PURPOSE: Ureteric stents placed after ureteroscopy typically require cystoscopy for removal. Stent extraction strings allow the option of patient self-removal. This facilitates shorter stent dwell time, and cost-savings. Concerns regarding safety and limited evidence regarding patient acceptability are speculated reasons for infrequent clinical use of extraction strings. This study investigates our recent experience using routine self-removal of stents on extraction strings to provide evidence to address these concerns. METHODS: In February 2020, our hospital adopted a policy for self-removal of stents on extraction strings to be routine following ureteroscopy. This was influenced by motivation to improve service capacity for diagnostic flexible cystoscopy, hospital avoidance during the pandemic, perceived improvement for the patient experience, and cost-saving. Prospective clinical and patient-reported outcome data were collected and evaluated. RESULTS: There were 168 patients who had stents on extraction strings. Mean stent dwell time was 5.2 ± 1.8 days. Primary ureteroscopy was performed in 40.5%, and 59.5% had procedures using an access sheath. Self-removal at home was successful for 79% of patients. Stent dislodgement rate was 3.0% (5/168) and retained stents due to string detachment occurred in 1.8% (3/168). Almost all indicated they "would remove the stent on string again" (90%, 128/142) and the majority reported stent removal as "very easy" (61%, 87/142). Cost modelling estimates a total saving of AUD $148,869 per annum for routine use of extraction strings at our hospital. CONCLUSION: Our experience reflects that stent extraction strings may be used routinely with acceptable low complication rates, favourable patient experiences and associated cost savings.

External ureteric stent versus internal double J stent in kidney transplantation: a retrospective analysis on the incidence of urological complications and urinary tract infections.

Introduction: Urologic complications (UCs) and urinary tract infections (UTIs) are common after kidney transplantation. Intraoperative stent placement at the vesicoureteric anastomosis reduces UC risk, but increases UTI risk. Methods: In 2014 our stenting protocol changed from external ureteric stent (ES) to internal double J stent (DJ). We retrospectively studied the occurrence of UCs and UTIs in relation to ES or DJ in 697 kidney recipients. Methods: An ES was used in 403 patients (57.8%), in 294 (42.2%) a DJ. ES was removed 7-12 days and DJ 3-4 weeks post-operative. Induction immunosuppression was the same in both groups. Primary outcomes at 6 months follow-up were UC (urinary leakage/ureter stenosis) and UTI; they were related to stenting procedure and clinical and transplant characteristics. The incidence of UCs was similar for ES (8.4%) and DJ (6.8%), p=0.389. ES use was a significant risk factor for UTI (OR 1.69 (1.15-2.50), p=0.008). Post-transplant hospitalization was significantly shorter in the DJ group. Despite more acute rejection episodes with ES (ES/DJ: 16.4%/6.1%, p<0.001), no clinical relevant differences in graft outcomes existed. Discussion: A DJ is, compared to ES, associated with a lower incidence of UTIs and comparable occurrence of UCs and is therefore the preferred technique for stenting the vesicoureteric anastomosis.

Bedside Flexible Cystoscopy-Guided Ureteric Stent Insertion for Early Control of Sepsis.

Sepsis is a life-threatening condition that needs the clinician to act quickly and swiftly in order to provide the best medical outcome for the patient. Sepsis can lead to multi-organ dysfunction, which is not only a risk to life but also utilizes multiple resources within the healthcare services. The management of any infection is reliant on two major factors: antimicrobial therapy and source control. We present two cases where source control, in the form of a ureteric stent insertion, was performed at bedside via the use of flexible cystoscopy to provide source control in the management of a septic patient.

Long-term Outcomes of Minimally Invasive Rendezvous Procedures to Treat Complex Ureteric Strictures and Injuries.

Background: Complex ureteric strictures and injuries occurring during major abdominal and pelvic operations may cause significant morbidity and distress to patients. A rendezvous procedure is an endoscopic technique used in case of such injuries. Objective: To evaluate perioperative and long-term outcomes of rendezvous procedures to treat complex ureteric strictures and injuries. Design setting and participants: We retrospectively reviewed patients undergoing a rendezvous procedure for ureteric discontinuity including strictures and injuries, treated between 2003 and 2017 at our Institution and completing at least 12 mo of follow-up. We divided patients into two groups: early postsurgical obstruction, leakage, or detachment (group A) and late strictures (oncological/postsurgical; group B). Outcome measurements and statistical analysis: If appropriate, we performed a retrograde study ± rigid ureteroscopy to assess the stricture 3 mo after the rendezvous procedure, followed by a MAG3 renogram at 6 wk, 6 mo, and 12 mo, and annually thereafter for 5 yr. Results and limitations: Forty-three patients underwent a rendezvous procedure, 17 in group A (median age 50 yr, range 30-78) and 26 in group B (median age 60 yr, range: 28-83). Ureteric strictures and ureteric discontinuities were stented successfully in 15 out of 17 patients in group A (88.2%) and 22 out of 26 patients (84.6%) in group B. For both groups, the median follow-up was 6 yr. In group A, of 17 patients, 11 (64.7%) were stent free with no further interventions, two (11.7%) had a subsequent Memokath stent insertion (38%), and two (11.7%) required reconstruction. Of 26 patients in group B, eight (30.7%) required no further interventions and were stent free, ten (38.4%) were maintained with long-term stenting, and one was managed with a Memokath stent (3.8%). Of the 26 patients, only three (11.5%) required major reconstruction, while four patients with malignancy (15%) died during follow-up. Conclusions: With a combined antegrade and retrograde approach, the majority of complex ureteric strictures/injuries can be bridged and stented with an overall immediate technical success rate of above 80%, avoiding major surgery in unfavourable circumstances and allowing time for stabilisation and recovery of the patient. Additionally, in case of technical success, further interventions may be unnecessary in up to 64% of patients with acute injury and about 31% of patients with late stricture. Patient summary: The majority of complex ureteric strictures and injuries can be resolved using a rendezvous approach, avoiding major surgery in unfavourable circumstances. Moreover, this approach can help avoid further interventions in 64% of such patients.

Outcomes Associated with the Endourological Management of Stent Encrustation: Findings from a Literature Review on Behalf of the EAU YAU Urolithiasis Group.

PURPOSE OF REVIEW: Double J ureteric stents (DJs) are useful aids for urinary drainage in case of stones or tumour causing ureteric obstruction. Prolonged dwelling time such as when forgotten can lead to encrustation. Our aim was to perform a literature review to evaluate outcomes associated with endourological management of encrusted stents (ES). RECENT FINDINGS: There now exist validated tools which can aid in grading the severity of encrustation and aid operative planning such as the total number of surgeries that may be required. Evaluation of different treatment strategies remains under reported. Removal of encrusted stent is a challenging problem, and it typically requires a multimodal endourological approach.

Iatrogenic ureteric injury during abdominal or pelvic surgery: a meta-analysis.

OBJECTIVE: To assess the incidence of ureteric injuries, clinical value of prophylactic ureteric stenting and impact of intra- or postoperative detection of ureteric injuries in patients treated with gynaecological or colorectal surgery. METHODS: Multiple databases were searched for articles published before September 2021 according to the Preferred Reporting Items for Systematic Review and Meta-Analyses statement. Studies were deemed eligible if they evaluated the differences in the rate of ureteric injuries between laparoscopic and open surgery, prophylactic ureteric stenting or not, and those of final treatment success between intra- and postoperative detection in patients who underwent gynaecological or colorectal surgery. RESULTS: Overall, 46 studies were eligible for this meta-analysis. Compared to open surgery, laparoscopic hysterectomy was associated with a higher incidence of ureteric injuries (pooled odds ratio [OR] 2.12, 95% confidence interval [CI] 1.71-2.62), but there was no statistically significant difference in colectomy (pooled OR 0.89, 95% CI 0.77-1.03). Prophylactic ureteric stenting was associated with a lower incidence of ureteric injuries during gynaecological surgery (pooled OR 0.61, 95% CI 0.39-0.96). The number needed to perform ureteric stenting to prevent one ureteric injury was 224 in gynaecological surgery. On the other hand, prophylactic ureteric stenting did not reduce the risk of ureteric injuries during colorectal surgery. Intraoperative detection of a ureteric injury was associated with a lower rate of complication management failure compared to postoperative detection (pooled OR 0.22, 95% CI 0.12-0.41). CONCLUSIONS: Laparoscopic hysterectomy seems to be associated with a higher rate of ureteric injuries compared to an open approach. Prophylactic ureteric stenting seems to reduce this risk during gynaecological surgery. Intraoperative detection of a ureteric injury during abdominal/pelvic surgery improves outcomes, suggesting the need for awareness and proactive problem identification. Further well-designed studies assessing the candidates who are more likely to benefit from prophylactic ureteric stenting including cost analysis are needed.

Indwelling stents cause obstruction and induce ureteral injury and fibrosis in a porcine model.

OBJECTIVES: To investigate global changes in ureters at the transcriptional, translational and functional levels, both while stents are indwelling and after removal and recovery, and to study the effects of targeting pathways that play a potential role. METHODS: Pig ureters were stented for varying amounts of time (48 h, 72 h, 14 days) and the impact on peristalsis, dilatation and hydronephrosis were assessed. RNAseq, proteomic, histological and smooth muscle (SM) function analyses were performed on ureteric and kidney tissues to assess changes induced by stenting and recovery. Pathway analysis was performed using Ingenuity Pathway Analysis software. To study the impact of possible interventions, the effects of erythropoeitin (EPO) and a Gli1 inhibitor were assessed. RESULTS: Stenting triggers massive ureteric dilatation, aperistalsis and moderate hydronephrosis within 48 h. Pathways associated with obstruction, fibrosis and kidney injury were upregulated by stenting. Increased expression of GLI1, clusterin-α (a kidney injury marker) and collagen 4A2 (a fibrosis marker) was found in stented vs contralateral unstented ureters. EPO did not improve peristalsis or contraction force but did decrease non-purposeful spasming seen exclusively in stented ureters. Tamsulosin administration increased contractility but not rate of peristalsis in stented ureters. CONCLUSIONS: Ureters respond to stents similarly to how they respond to an obstruction, that is, with activation of pathways associated with hydronephrosis, fibrosis and kidney injury. This is driven by significant dilatation and associated ureteric SM dysfunction. EPO and tamsulosin induced mild favourable changes in SM physiology, suggesting that targeting specific pathways has potential to address stent-induced complications.

Primary Definitive Treatment versus Ureteric Stenting in the Management of Acute Ureteric Colic: A Cost-Effectiveness Analysis.

Objectives: To analyze the differences in cost-effectiveness between primary ureteroscopy and ureteric stenting in patients with ureteric calculi in the emergency setting. Patients and Methods: Patients requiring emergency intervention for a ureteric calculus at a tertiary centre were analysed between January and December 2019. The total secondary care cost included the cost of the procedure, inpatient hospital bed days, emergency department (A&E) reattendances, ancillary procedures and any secondary definitive procedure. Results: A total of 244 patients were included. Patients underwent ureteric stenting (62.3%) or primary treatment (37.7%), including primary ureteroscopy (URS) (34%) and shock wave lithotripsy (SWL) (3.6%). The total secondary care cost was more significant in the ureteric stenting group (GBP 4485.42 vs. GBP 3536.83; p = 0.65), though not statistically significant. While mean procedural costs for primary treatment were significantly higher (GBP 2605.27 vs. GBP 1729.00; p < 0.001), costs in addition to the procedure itself were significantly lower (GBP 931.57 vs. GBP 2742.35; p < 0.001) for primary treatment compared to ureteric stenting. Those undergoing ureteric stenting had a significantly higher A&E reattendance rate compared with primary treatment (25.7% vs. 10.9%, p = 0.02) and a significantly greater cost per patient related to revisits to A&E (GBP 61.05 vs. GBP 20.87; p < 0.001). Conclusion: Primary definitive treatment for patients with acute ureteric colic, although associated with higher procedural costs than ureteric stenting, infers a significant reduction in additional expenses, notably related to fewer A&E attendances. This is particularly relevant in the COVID-19 era, where it is crucial to avoid unnecessary attendances to A&E and reduce the backlog of delayed definitive procedures. Primary treatment should be considered concordance with clinical judgement and factors such as patient preference, equipment availability and operator experience.

Emergency Primary Ureteroscopy for Acute Ureteric Colic-From Guidelines to Practice.

OBJECTIVE: To review the factors that may influence the ability to achieve the present guidelines' recommendations in a well-resourced tertiary centre. According to current National Institute for Health and Care Excellence (NICE) guidelines, definitive treatment (primary ureteroscopy (URS) or shock wave lithotripsy (ESWL)) should be offered to patients with symptomatic renal colic that are unlikely to pass the stone within 48 h of diagnosis. METHODS: Retrospective review of all patients presenting to the emergency department between January and December 2019 with a ureteric or renal stone diagnosis. The rate of emergency intervention, risk factors for intervention and outcomes were compared between patients who were treated by primary definitive surgery vs. primary symptom relief by urethral stenting alone. RESULTS: A total of 244 patients required surgical management for symptomatic ureteric colic without symptoms of urinary infection. Of those, 92 patients (37.7%) underwent definitive treatment by either primary URS (82 patients) or ESWL (9 patients). The mean time for the procedure was 25.5 h (range: 1-118). Patients who underwent primary definitive treatment were likelier to have smaller and distally located stones than the primary stenting group. Primary ureteroscopy was more likely to be performed in a supervised setting than emergency stenting. CONCLUSIONS: Although definitive treatment carries high success rates, in a high-volume tertiary referral centre, it may not be feasible to offer it to all patients, with emergency stenting providing a safe and quick interim measure. Factors determining the ability to provide definitive treatment are stone location, stone size and resident supervision in theatre.

Stent diameter and stent-related symptoms, does size matter? A systematic review and meta-analysis.

The ureteral insertion of a silicone tube was first performed in 1967. A validated ureteral stent symptom questionnaire (USSQ) is used for an objective assessment of patient-reported stent-related symptoms. As the impact of stent diameter on the incidence of stent-related symptoms is unclear, we aimed to perform a systematic review and meta-analysis comparing USSQ reported outcomes when using a 6 Fr diameter ureteric stent, versus smaller diameter stents (4.7-5 Fr) when inserted for ureteric stones. All randomized control trials and comparative studies of 6 Fr versus 4.7-5 Fr ureteric stents were reviewed. The USSQ outcomes were considered as the primary outcome measures while stent migration was considered as a secondary outcome measure. A total of 61 articles were identified of which four studies met the eligibility criteria. There was a statistically significant association between the use of wider (6 Fr) diameter stents and the incidence of urinary symptoms as measured by the urinary index score. Larger stent diameters were associated with a statistically significant increase in the pain index score. There was no statistically significant difference in the scores between the compared stent diameters with regard to work performance score, general health index score, additional problems index score, and stent migration. There were insufficient reported outcomes to perform a meta-analysis of sexual matters index score. Our meta-analysis shows that using smaller diameter ureteric stents is associated with reduced urinary symptoms and patient-reported pain. Other USSQ parameter outcomes are statistically similar in the 6 Fr ureteric stent cohort versus the 4.7-5 Fr ureteric stent cohort. Our meta-analysis was limited due to the limited number of studies and gross heterogeneity of reporting parameters in various studies. We hope a large-scale homogeneous randomized control trial will further shed more insight into the stent symptoms response to stent diameter.