The current role of endourologic management of renal transplantation complications

The Effectiveness of the Surgical Correction of Vesicoureteral Reflux on Febrile Urinary Tract Infections after a Kidney Transplant: A Single-Center Retrospective Study

Background/Objectives: Vesicoureteral reflux (VUR) is considered one of the major causes of post-renal transplant febrile urinary tract infections (UTI), leading to impaired renal function and the premature loss of the renal graft. We aimed to evaluate whether surgical VUR correction, such as open redo ureteric reimplantation, could be an option for treatment and provide better outcomes in post-transplant care for patients with UTI compared to their pre-VUR correction clinical state. Methods: Our study presents a retrospective analysis of 10 kidney transplant recipients with febrile UTI at the Renal Transplant Service of a Brazilian public hospital from 2010 to 2020. We selected patients who primarily underwent a surgical correction of post-transplant VUR, which was corrected by extravesical reimplantation without a stent in all patients by the same professional surgeon. Results: From 710 patients who received kidney transplants, 10 patients (1.4%) suffered from febrile UTI post-transplant and underwent surgical correction for VUR. Despite the study's limitations, such as its retrospective nature and limited sample size, the efficacy of open extravesical ureteral reimplantation in reducing post-operative febrile UTI in renal transplant patients was observed. Conclusions: As febrile UTI can contribute significantly to patient mortality after kidney transplantation and VUR emerges as a major cause of post-transplant febrile UTI, it is essential to treat it and consider the surgical outcome. This study emphasizes the timely detection and effective treatment of VUR via extravesical techniques to reduce febrile UTI occurrences post-transplant and it contributes insights into the role of surgical interventions in addressing VUR-related complications post-kidney transplantation.

Percutaneous nephrolithotomy for adult renal transplant de novo graft lithiasis: a single center analysis and systematic review of the literature

INTRODUCTION/OBJECTIVE

Graft stones in renal transplant recipients pose a unique challenge, finding effective interventions to ensure optimal graft function and patient well-being. Various methods of stone clearance have been described for graft stones, including percutaneous nephrolithotomy (PCNL). While PCNL is a promising approach for managing graft stones, specific outcomes and associated characteristics for this approach have not been comprehensively evaluated before. This study aims to evaluate the safety and efficacy of the use of PCNL as the primary intervention of graft stones by assessing stone-free rates (SFR), treatment impact on graft function, and perioperative complications.

METHODS

A retrospective clinical audit was performed for all transplants performed in a single center from 2007 to 2022, which included all graft lithiasis patients who were treated with PCNL. Both perioperative parameters and post-operative outcomes were collected. In addition, a systematic review including articles from MEDLINE, Embase, Web of Science yielded 18 full-text articles published between 1/1/2000 and 15/11/2023. The results pertaining to patients who underwent PCNLs for graft stones were cross-referenced and thoroughly evaluated. The review encompassed a comprehensive analysis of clinical data, postoperative outcomes, and procedural details. The protocol for the systematic review was prospectively registered on PROSPERO (CRD42023486825).

RESULTS

In our center, 6 graft lithiasis patients were treated with PCNL. The initial SFR was 83.3%. SFR at 3 months and 1 year were both 100.0%. SFR at 3 years was 66.7%. Other centers reported initial SFR of 82.6-100.0% (interquartile range). SFR at 3 months, 1 year, 3 years was not well reported across the included studies. Incidence of graft lithiasis ranged from 0.44%-2.41%. Most common presentations at diagnosis were oliguria/anuria/acute kidney injury and asymptomatic. Reported complications included blood loss, transient hematuria, high urine output, sepsis, and damage to surrounding structures. The most commonly reported metabolic abnormalities in transplant lithiasis patients included hyperuricemia and hyperparathyroidism.

CONCLUSION

PCNL is a practical and efficient choice for addressing graft lithiasis, demonstrating excellent stone clearance and minimal perioperative complications. These findings show the importance of PCNL as a primary intervention in this complex patient population.

DIFFERENT APPROACHES TO MANAGING UROLITHIASIS IN KIDNEY TRANSPLANT PATIENTS - A CASE REPORT

Urolithiasis is a rare urologic complication after kidney transplantation, and its diagnosis and treatment can be challenging for clinicians. In our 52-year-old male patient, graft hydronephrosis was found six months after transplantation. The patient had recurrent urinary tract infections followed by macrohematuria and an increase in creatinine levels. Computerized tomography revealed a 13-mm diameter stone in the ureter of the transplanted kidney as the cause of obstruction. Percutaneous nephrostomy was placed in the graft to solve the obstruction. Initial endoscopic treatment with a retrograde approach failed. An antegrade approach through a previously placed nephrostomy was not successful either. By a repeated retrograde approach, laser lithotripsy was performed successfully. The patient has been monitored for six months and has stable graft function without hydronephrosis or stones. As in our patient's case, the diagnosis and treatment of urolithiasis in kidney transplant patients is challenging, and minimally invasive procedures are the treatment of choice.

A STENTLESS MODIFIED LICH-GREGOIR TECHNIQUE FOR SAFE EARLY BLADDER CATHETER REMOVAL IN LIVING AND DECEASED KIDNEY TRANSPLANTS

OBJECTIVES

To describe a stentless modified Lich-Gregoir technique (mLG) for ureteroneocystostomy in renal transplantation (RT), with early bladder catheter (BC) removal (under 48 hours), and compare the postoperative results with those of the traditional technique (LG) with routine bladder catheter removal (4 to 5 days). The modification consists of maintaining a thin layer of detrusor fibers covering the bladder mucosa during dissection, which is incorporated into the anastomosis to reinforce the ureteroneocystostomy.

MATERIALS AND METHODS

This retrospective cohort study compared the postoperative outcomes of 100 consecutive patients who underwent mLG with early removal of BC between October 2018 to November 2019 with those of a historical cohort of 165 consecutive patients transplanted using stentless LG and routine removal of BC, who underwent surgery between July 2017 and September 2018. All transplants were performed by the same surgeon. Follow-up was 6 months.

RESULTS

Demographic characteristics were comparable, although patients in the mLG group had a higher mean preoperative urine volume (911±753.8mL vs. 629±638.6mL, p=0.016). Patients in the mLG group successfully underwent early BC removal (2.2±0.9 vs. 4.8±4.8 days, p<0.001), with no differences in the incidence of surgical or clinical complications, including urine leaks (1 vs. 3%, p=0.284). In addition, mLG patients presented a shorter mean length of hospital stay (6.5±5.0 vs. 7.1±6.2 days, p=0.023).

CONCLUSION

This stentless modified Lich-Gregoir technique enables safe early bladder catheter removal and is associated with reduced hospital length of stay.

Endourological application of polydimetilsiloxane in patients with symptomatic vesicoureteral reflux in the kidney graft

OBJECTIVE

To identify the results of polydimethylsiloxane application in the endourological management of symptomatic vesicoureteral reflux to the kidney graft and to determine the factors associated with persistent symptoms and with vesicoureteral reflux.

MATERIAL AND METHODS

We included 23 patients diagnosed with symptomatic VUR in kidney graft, evaluated from January 2010 to August 2018 in the High Specialty Medical Unit # 14 in Veracruz. These patients received endourological application of polydimethylsiloxane. The descriptive analysis was carried out, and, if possible, the relative risk measures for clinical failure (CF) were determined with odds ratio (OR).

RESULTS

18 (78.3%) patients presented clinical success (CS). There was a significant difference in the mean age (CS 30.61±9.7, CF 46.0±11.46; U Mann Whitney, P=.037), and in the number of episodes of AGPN prior to the application of PDMS (CS 2.27±1.27, CF 3.6±0.89, U Mann Whitney, P=.019). The most frequently identified pathogen was E. Coli, with 45.4%. VUR resolution was observed in 47.8% of the cases. There was a decreased degree of VUR in 73.9% of cases. A lower degree of VUR was determined as a protective factor for CF (OR: 0.031, 95% CI: 0.002-0.437, with P=.008).

CONCLUSIONS

The endourological application of PDMS proved to be useful in the management of patients with symptomatic VUR in kidney graft, as it decreased the VUR degree and allowed CS in most cases.

Comparing treatment modalities for transplant kidney vesicoureteral reflux in the pediatric population

INTRODUCTION

Non-refluxing ureteral reimplantation is favored in pediatric renal transplantation to prevent complications, such as vesicoureteral reflux (VUR) in the transplant ureter. VUR resulting in febrile urinary tract infections remains a problem in this population, leading to repeated hospitalizations and increased morbidity. Revision of the vesicoureteral anastomosis can be a surgical challenge due to scar tissue and tenuous vascularity of the transplant ureter. Therefore, alternative options such as endoscopic injection of Deflux at the neo-orifice and surveillance with prophylactic antibiotics have emerged as potential treatment modalities for transplant ureter VUR.

OBJECTIVE

The authors reviewed their experience of the management of VUR in the transplant ureter, comparing outcomes of various modalities.

STUDY DESIGN

With Institutional Review Board approval, a retrospective chart review of all renal transplant patients from January 2002 to January 2017 was conducted. All patients with VUR on voiding cystourethrogram (VCUG) after surgery were identified. Indications for end-stage renal disease, urologic comorbidities, pretransplant VCUG, and operative details were recorded. After transplantation, febrile urinary tract infections, ultrasound findings, and any further interventions-surveillance, subureteral endoscopic injection of Deflux, or ureteral reimplantation-were documented along with their outcomes.

RESULTS

Overall, VUR was identified in 35/285 (12.3%) transplant patients after a non-refluxing ureteroneocystostomy. VUR was managed with surveillance in 17/35 (49%), intravesical Deflux injection in 11/35 (31%), and immediate redo ureteral reimplantation in 7/35 (20%). Ten out of 11 patients undergoing Deflux injection had a postoperative VCUG. All patients developed VUR recurrence; the majority showed immediate failure and only 1/10 showed late recurrence. Of the immediate failures, 3/9 patients were maintained on prophylactic antibiotics, and 6/9 patients underwent ureteral reimplantation. In these six patients undergoing reimplantation after failed Deflux, 3/6 (50%) patients required additional surgeries: One patient developed recurrence of reflux and two patients developed ureterovesical junction obstruction. In contrast, no complications were seen in patients undergoing primary ureteral reimplantation.

DISCUSSION

The study is limited by low numbers and a retrospective design. However, the results of this study differ significantly from the published Deflux series showing a success rate of more than 50% in the treatment of transplant kidney VUR. In fact, post-Deflux redo ureteral reimplantation was associated with an increased risk of postoperative complication.

CONCLUSION

The use of Deflux in the post-transplant setting has poor results. In the study series, 11/11 patients demonstrated clinical and radiographic failure. Therefore, as an institution the authors do not recommend Deflux as first-line treatment of VUR in the transplant patient.

Routine double-J stenting for live related donor kidney transplant recipients: It doesn't serve the purpose, but does it serve a better purpose?

Purpose

Despite meticulous techniques, surgical complications continue to be problematic in kidney transplant recipients. Role of routine stenting to reduce complications is controversial. In this study, we compare incidence of early urological complications, lymphoceles, urinary tract infections (UTI) and graft function; with or without double-J stenting.

Materials and Methods

All patients who underwent live related donor renal transplantation from February 2014 to February 2016 were included. Transplants prior to February 2015 were without routine stenting; subsequent transplants were with routine stenting. Patients with neurogenic bladder, previously operated bladder and delayed or low urinary output were excluded. Follow-up was for at least three months. Descriptive statistics was performed for all parameters. Chi square test and Fisher's Exact test were used for qualitative variables. For quantitative variables, Mann-Whitney test was used to test median difference and independent samples t-test for mean difference. The p-value ≤0.05 was considered significant.

Results

We analysed 74 patients (34 stented and 40 non-stented). There was no difference in the incidence of urinary leak, anastomotic obstruction, lymphoceles or UTI (p>0.4 for all comparisons). However, mean estimated glomerular filtration rate at sixth day, 14th day, one month and two months were 76.1 vs. 61.5 (p=0.025), 72.1 vs. 56.6 (p=0.005), 79.4 vs. 63.1 (p=0.002) and 82.0 vs. 63.3 (p=0.001) in the stented versus non-stented groups.

Conclusions

Placement of ureteral stent in renal transplant does not significantly affect the incidence of early urinary complications or UTI. However, graft function is significantly better in stented recipients, at least in the short term.

Retrograde Intrarenal Surgery Through an Incision of the Ureter as a Good Treatment Option for Large Ureteropelvic Impacted Stones in Transplanted Kidneys

Urolithiasis is a rare complication after kidney transplant. Over the years, treatment of kidney stones has evolved radically, but a standard approach for transplanted kidneys has not yet been defined. Here, we present a 69-year-old male patient who received successful treatment of nephrolithiasis of the transplanted kidney. The patient, who had received a kidney from a deceased donor, was admitted to our department following a posttransplant Doppler ultrasonography showing severe hydronephrosis of the transplanted kidney associated with acute renal function decay. Computed tomography scan confirmed the hydronephrosis of the transplanted kidney, showing a large, impacted, ureteropelvic 3-cm-diameter stone and other concretions around the ureteral stent. The patient was then treated with retrograde intrarenal surgery during an open ureterotomy. His postoperative course was uneventful, and he showed good functional reprise and a rapid decrease of serum creatinine levels. Intraoperative retrograde intrarenal surgery could be a valid option for treatment of kidney stones of the transplanted kidney during open surgery of the ureter or during ureterovesical anastomosis.

Endoscopic Management of Ureteral Strictures: an Update

PURPOSE OF REVIEW

This review focuses on the role of endoscopic treatment of ureteral stricture disease (USD) in the era of minimally invasive surgery.

RECENT FINDINGS

There is a relative paucity of recent literature regarding the endoscopic treatment of USD. Laser endopyelotomy and balloon dilation are associated with good outcomes in treatment-naïve patients with short (< 2 cm), non-ischemic, benign ureteral strictures with a functional renal unit. If stricture recurs, repetitive dilation and laser endopyleotomy is not recommended, as success rates are low in this scenario. Patients with low-complexity ureteroenteric strictures and transplant strictures may benefit from endoscopic treatment options, although formal reconstruction offers higher rates of success. Formal ureteral reconstruction remains the gold-standard treatment for ureteral stricture disease as it is associated with higher rates of complete resolution. However, in carefully selected patients, endoscopic treatment modalities provide a low-cost, low-morbidity alternative.

Safety of potassium-bearing citrate in patients with renal transplantation: A case report

RATIONALE

Urinary lithiasis is one of severe postoperative complications in patients undergoing renal transplantation, possibly leading to anuria, urinary infection, or even acute renal failure. Potassium sodium hydrogen citrate (PSHC), a potassium-bearing citrate, is commonly prescribed to prevent stone formation.

PATIENT CONCERNS

A 25-year-old man (patient 1) and a 31-year-old man (patient 2) receiving renal transplantation for end-stage renal disease (ESRD) were enrolled in this study. They were given 10 g/day of PSHC granules from the ninth day to the 17th day after surgery. Patient 1 presented chest tightness, nausea, muscle weakness, and ascending paralysis on the 10th day. Patient 2 presented weak waves on EGG on the 17th day. Moreover, their serum potassium concentrations (SPCs) were 7.67 and 6.05 mmol/L, respectively.

DIAGNOSIS

Acute hyperkalemia.

INTERVENTIONS

Hemo-filtration was performed for patient 1, while patient 2 received 10% calcium gluconate 10 mL, 5% NaHCO3 125 mL, and 10% glucose 500 mL with the addition of 10 units of insulin through intravenous drip.

OUTCOMES

Their SPCs dropped to the normal range.

LESSONS

Physicians should pay close attentions to potential risks caused by PSHC, and monitor the SPCs to minimize the occurrence of hyperkalemia.

Outcomes of Kidney Transplant Recipients With Percutaneous Ureteral Interventions: A Single-Center Study

Background

Long-term outcomes of kidney transplantation recipients with percutaneous ureteral management of transplant ureteral complications are not well characterized.

Methods

Electronic records of 1753 recipients of kidney-alone transplant between January 2000 and December 2008 were reviewed. One hundred thirty-one patients were identified to have undergone percutaneous ureteral management, with placement of percutaneous nephrostomy tube or additional intervention (nephroureteral stenting and/or balloon dilation). Indications for intervention included transplant ureteral stricture or ureteral leak. Kaplan-Meier survival curves and multivariable regression modeling were performed to determine survival outcomes.

Results

Kaplan- Meier graft survival (P = 0.04) was lower in patients with percutaneous ureteral intervention for transplant ureteral complication. Graft survival at 1, 5, and 10 years was 94.3% 78.3%, and 59.1% for no intervention and 97.2%, 72.1%, and 36.2% for intervention cohort. Patient survival (P = 0.69) was similar between cohorts. Multivariate analysis demonstrated no association with graft failure (hazard ratio, 1.21; 95% confidence interval, 0.67-2.19; P = 0.53) or patient death (hazard ratio, 0.56; 95% confidence interval, 0.22-1.41; P = 0.22) in intervention group. The major cause of graft failure was infection for percutaneous ureteral intervention group (20.4%) and chronic rejection for those without intervention (17.3%).

Conclusions

Kidney transplant recipients with percutaneous ureteral interventions for ureteral complications do not have a significant difference in graft and patient survival outcomes. Therefore, aggressive nonoperative management can be confidently pursued in the appropriate clinical setting.

The development and current status of minimally invasive surgery to manage urological complications after renal transplantation

Introduction:

In the past, urological complications after renal transplantation were associated with significant morbidity. With the development and application of endourological procedures, it is now possible to manage these cases with minimally invasive techniques.

Materials and Methods:

A MEDLINE search for articles published in English using key words for the management of urological complications after renal transplantation was undertaken. Forty articles were selected and reviewed.

Results:

The incidence of urological complications postrenal transplantation was reported to be 2–13%. Ureteric leaks occurred in up to 8.6%, and 55% were managed endourologically. The incidence of lymphocele was as high as 20%, and less that 12% of the cases required treatment. Ureteric stricture was the most common complication, and endourological management was successful in 50–70%. The occurrence of complicated vesicoureteral reflux was 4.5%, and 90% of low-grade reflux cases were successfully treated with deflux injections. Stones and obstructive voiding dysfunction occurred in about 1% of kidney transplant recipients.

Conclusion:

Minimally invasive techniques have a critical role in the management of urological complications after renal transplantation. Urinary leakage should be managed with complete decompression. Percutaneous drainage should be the first line of treatment for lymphocele that is symptomatic or causing ureteric obstruction. Laparoscopic lymphocele deroofing is successful in aspiration-resistant cases. Deflux is highly successful for the management of complicated low-grade kidney transplant reflux. The principles of stone management in a native solitary kidney are applied to the transplanted kidney. Early identification and treatment of bladder outlet obstruction after renal transplantation can prevent urinary leakage and obstructive uropathy.

Effect of dexmedetomidine on rats with renal ischemia-reperfusion injury and the expression of tight junction protein in kidney

To explore the protective effect of dexmedetomidine (Dex) on rats with renal ischemia-reperfusion injury and the influence of Dex on the expression of tight junction protein in kidney. Grouped 40 SPF male rats into 4 groups, sham operation group (group S), ischemia-reperfusion group (group I/R), pretreatment with Dex group (group Pre/Dex), post-treatment with Dex group (group Post/Dex), randomly, 10 rats each group. Rats in group S were anaesthetized and set up with removal of right kidney; rats in group I/R were set up with removal of right kidney and left renal artery clamping for 45 min followed by 60 min reperfusion; rats in group Pre/Dex were intravenous injected with Dex (1 μg/kg) for 30 min after indwelling catheter via femoral vein puncture; rats in group Post/Dex were intravenous injected with Dex (1 μg/kg) for 30 min after left renal reperfusion. The kidneys in each group were made out pathologic slices after 6 h I/R, stained with HE; blood samples were taken with separation plasma, creatinine (Scr) and urea nitrogen (BUN) were detected by automatic biochemical analyzer; IL-1β and TNF-α were detected by Enzyme-linked Immunosorbent Assay (ELISA); the expression level of tight junction protein ZO-1 and protein occludin in kidney were detected by Western-blot. The results of HE staining showed that, comparing to group S, the tissue of kidney in group I/R were damaged heavily with tubules dilatation and inflammation obviously, while lightened in group Pre/Dex and group Post/Dex. The results of detection of renal function and inflammatory factors showed that, comparing to group S, Scr, BUN, IL-1β and TNF-α were all enhanced in group I/R, group Pre/Dex and group Post/Dex, significantly (P < 0.05), while the inflammatory factors in group Pre/Dex and group Post/Dex were lower than in group I/R, significantly (P < 0.05). The results of Western-blot showed that the expression of protein ZO-1 and occludin in group Pre/Dex and group Post/Dex were higher than in group I/R, significantly (P < 0.05). Dex could reduce renal dysfunction induced by I/R, inhibit inflammatory response, up-regulate the expression of protein ZO-1 and occludin and protect renal.

Impact of ureteral stenting on urological complications after kidney transplantation surgery: a single-center experience

BACKGROUND

Urological complications such as ureteral strictures and ureteral leakage can affect the outcome of kidney transplantation by increasing morbidity and mortality, including graft loss. Controversy still exists regarding the role of stents in renal transplantation. The aim of this study was to evaluate the role of ureteral stenting in kidney transplantation.

METHODS

We performed a retrospective study on a series of 798 consecutive renal transplants performed in our center between January 1, 2004, and December 31, 2011. Ureteral stents were used in 152 cases (19.1%) of the total (stent group) and were removed 2 weeks postoperatively. Donor and recipient age, sex, type of ureteroneocystostomy, stent and non-stent patients, cold and warm ischemia time, and urological complications were analyzed.

RESULTS

The overall incidence of urological complications was 7.8% (62 cases). Ureteral stenosis (3.1%) and ureteral leakage (2.4%) were the most common complications; 39.7% (25 cases) of complications were recorded in the first month after transplantation. Major urological complication rate was 3.3% in the stent group compared with 8.8% in the non-stent group (P = .04). However, stent use was associated with the increase of urinary tract infections rate in the stent group (51.3%) compared with the non-stent group (17.9%) (P = .03).

CONCLUSIONS

In our study, the use of ureteral stents significantly decreased urological complications in kidney transplant recipients but increased the risk for development of urinary tract infections.

Urologic considerations and complications in kidney transplant recipients

Urologic considerations during the kidney transplantation process, starting with initial recipient evaluation and continuing through the post-transplant, long-term follow-up, are critical for minimizing urologic complications and improving graft survival. Appropriate, targeted, preoperative urologic evaluation of the recipient allows for an optimized urinary tract to accept the graft, whereas post-transplant urologic follow-up and monitoring decrease the risk of graft lost secondary to a urologic cause, particularly in patients with a urologic reason for their kidney failure and in those patients with concomitant urologic diagnoses. Urologic complications comprise the second most common adverse post-transplant event, occurring in 2.5% to 14% of patients and are associated with high morbidity, graft loss, and mortality. Early and late urologic complications, including hematuria, hematoma, lymphocele, urine leak, ureteral stricture, nephrolithiasis, and vesicoureteral reflux, and their causes and treatment options are explored. A multidisciplinary team approach to kidney transplantation, including transplant surgery, urology, and nephrology, optimizes outcomes and graft survival. Although the current role of the urologist in kidney transplantation varies greatly by institution, appropriate consultation, participation, and monitoring in select patients is essential.

Use of Self-Expanding Metallic Ureteral Stents in the Secondary Treatment of Ureteral Stenosis Following Kidney Transplantation

INTRODUCTION

To evaluate the safety and efficacy of self-expanding metal stents in the treatment of ureteral stenosis following kidney transplantation.

MATERIALS AND METHODS

Seven patients who developed benign stenosis after kidney transplantation were treated by a self-expanding metallic stent implantation from June 2007 to March 2014. All patients had undergone at least one open surgical procedure and one endourologic procedure for treatment of the stenosis. The extent of stenosis varied from 1.2 to 3.7 cm. Ultrasonography, urography, diuretic renography, and urine culture were performed every 3 months after stent insertion. Ureteroscopic examination was performed when needed.

RESULTS

Stent placement was technically effective in all cases. The mean operative time was 37 minutes (range, 26-59 minutes). Lower urinary-tract symptoms and the ipsilateral flank pain were common early-stage complications and were greatly relieved after an average of 3 months. The mean follow-up duration was 38 months (range, 13-86 months), and no stent migration or fragmentation was observed. Urothelial hyperplasia occurred in only one patient and was effectively managed with a Double-J stent. Five patients had normal stable renal function; the remaining two had impaired renal function, including one patient with a preoperative renal failure who required dialysis at the end of the follow-up period (36 months).

CONCLUSIONS

As an alternative to open surgery, implantation of a self-expanding metal stent is a safe and effective treatment for ureteral stenosis in patients who have undergone kidney transplantation.

Independent risk factors for early urologic complications after kidney transplantation

Urologic complications are the most frequent technical adverse events following kidney transplantation (KTX). We evaluated traditional and novel potential risk factors for urologic complications following KTX. Consecutive KTX recipients between December 1, 2006 and December 31, 2010 with at least six-month follow-up (n = 635) were evaluated for overall urologic complications accounting for donor, recipient, and transplant characteristics using univariate and multivariate logistic regression. Urologic complications occurred in 29 cases (4.6%) at a median of 40 d (range 1-999) post-transplantation and included 17 ureteral strictures (2.6%), five (0.8%) ureteral obstructions due to donor-derived stones or intraluminal thrombus, and seven urine leaks (1.1%). All except two complications occurred within the first year of transplantation. Risk factors for urologic complications on univariate analysis were dual KTX (p = 0.04) and renal artery multiplicity (p = 0.02). On multivariate analysis, only renal artery multiplicity remained significant (aHR 2.4, 95% confidence interval 1.1, 5.1, p = 0.02). Donation after cardiac death, non-mandatory national share kidneys, donor peak serum creatinine > 1.5 mg/dL or creatinine phosphokinase > 1000 IU/L, and donor down time were not associated with urologic complications. Our data suggest that donor artery multiplicity is an independent risk factor for urologic complications following KTX.

Ureteral strictures revisited…trying to see the light at the end of the tunnel: a comprehensive review

A ureteral stricture is a rather rare urological event defined as a narrowing of the ureter causing a functional obstruction and renal failure, if left untreated. The aim of this review article is to summarize and discuss current knowledge on the incidence, pathogenesis, management, and follow up of proximal, mid, and distal ureteral strictures.

Ureteral obstruction following renal transplantation: causes, diagnosis and management

Renal transplantation, first performed successfully in the 1950s, is the treatment of choice for most patients with end-stage renal failure. It confers longer term survival and a better quality of life than do both haemodialysis and peritoneal dialysis. The success of renal transplantation is dependent on the preservation of renal graft function and despite the many advances in surgical techniques, immunosuppressive regimens and supportive therapies, many challenges remain including post-operative ureteral obstruction. This complication can pose a risk to graft, and, occasionally, to patient survival. In this pictorial review, we describe the causes of ureteral obstruction following renal transplantation and illustrate the pivotal role of radiology in both diagnosing and managing these complications.