Vesicoureteral reflux after kidney transplantation in children

Current management of symptomatic vesicoureteral reflux in pediatric kidney transplantation-A European survey among surgical transplant professionals

BACKGROUND

Vesicoureteral reflux (VUR) is common in children and adolescents undergoing kidney transplantation (KTx) and may adversely affect allograft kidney function.

METHODS

To explore the current management of symptomatic native and allograft VUR in pediatric KTx recipients, an online survey was distributed to European surgical transplant professionals.

RESULTS

Surgeons from 40 pediatric KTx centers in 18 countries participated in this survey. Symptomatic native kidney VUR was treated before or during KTx by 68% of the centers (all/selected patients: 33%/67%; before/during KTx: 89%/11%), with a preference for endoscopic treatment (59%). At KTx, 90% favored an anti-reflux ureteral reimplantation procedure (extravesical/transvesical approach: 92%/8%; preferred extravesical technique: Lich-Gregoir [85%]). Management strategies for symptomatic allograft VUR included surgical repair (90%), continuous antibiotic prophylaxis (51%), bladder training (49%), or noninterventional surveillance (21%). Redo ureteral implantation and endoscopic intervention for allograft VUR were equally reported (51%/49%).

CONCLUSIONS

This survey shows uniformity in some surgical aspects of the pediatric KTx procedure. However, with regard to VUR, there is a significant variation in practice patterns that need to be addressed by future well-designed and prospective studies. In this way, more robust data could be translated into consensus guidelines for a more standardized and evidence-based management of this common condition in pediatric KTx.

Renal transplantation in pediatric recipients: Considerations and preoperative assessment strategies

INTRODUCTION AND OBJECTIVE

Renal transplantation in the pediatric population differs from adults in many aspects. This review will focus on the unique issues of the pediatric recipient.

MATERIAL AND METHODS

A narrative review on the scarce literature regarding preoperative evaluation before kidney transplantation of the paediatric recipient with an educational focus was conducted. The literature search allowed for identification of publications in English from January 2000 to October 2022. Published studies were identified by searching the following electronic databases: PubMed (MEDLINE), WHO/UNAIDS, Google-Scholar, Semantic-Scholar and Research Gate. For efficiency and reliability, recent randomized controlled trials, meta-analyses, high quality systematic reviews and large well-designed studies were used if available. Internet searches were conducted for other relevant information (definitions, policies or guidelines).

RESULTS

Management of congenital urogenital anomalies and lower urinary tract dysfunction along with optimal pediatric urological preoperative assessment for renal transplantation in children is addressed in the light of the available literature. Furthermore, particular considerations including pre-emptive transplantation, transplantation of an adult-size kidney into an infant or small child is discussed.

CONCLUSIONS

Outcomes of RT in children have shown progressive improvement over the past 15 years. Transplantation with living related donor gives the best results and pre-emptive transplantation provides with benefits of avoiding dialysis. Surgical and medical considerations in both the pre-transplant and post-transplant management of the pediatric kidney recipient are extremely crucial in order to achieve better short and long-term results.

Revision ureteroneocystostomy in pediatric renal transplant patients for symptomatic vesicoureteral reflux and its effect on recurrent hospitalizations

BACKGROUND

Nearly 13,000 pediatric renal transplantations have been performed since 1987 with improving overall mortality and morbidity; however, graft infection remains a significant post-transplant concern. Recurrent urinary tract infections in pediatric patients with vesicoureteral reflux into their renal transplant can result in graft dysfunction, increased hospital cost, and impaired social and cognitive development due to time spent hospitalized.

OBJECTIVE

To evaluate the effect of revision ureteroneocystostomy on pediatric renal transplant patients with symptomatic vesicoureteral reflux in reducing hospitalizations and recurrent urinary tract infections.

METHODS

We retrospectively reviewed pediatric patients from 2002 through 2021 who underwent renal transplantation and required revision ureteroneocystostomy due to symptomatic vesicoureteral reflux. We analyzed the differences in days hospitalized, days hospitalized due to urinary tract infection, and treated urinary tract infections prior to and after revision ureteroneocystostomy.

RESULTS

Ten patients requiring revision ureteroneocystostomy secondary to symptomatic vesicoureteral reflux were identified. There was no difference in the observation time between transplant to revision, and revision to last follow up (2.3 years (IQR 1.3-6.5) vs 1.7 years (IQR 1-6.7), p = 0.4446). Overall, there was a significant decrease in the total number of hospitalization days (21.5 days (IQR 3-43) vs 5.5 days (IQR 0-9), p = 0.006), total number of hospitalization days related to urinary tract infection (14.5 days (IQR 3-28) vs 0 days (IQR 0-3), p = 0.008) and treated urinary tract infections (3.5 (IQR 3-6) vs 1 (IQR 0-2), p = 0.019) following revision ureteroneocystostomy. The rate of hospitalization days for urinary tract infection was also significantly decreased following revision ureteroneocystostomy (7.15 per/year (IQR 0.4-11.75) vs 0 per/year (IQR 0-0.8), p = 0.008).

DISCUSSION

Symptomatic vesicoureteral reflux in pediatric transplant patients is difficult to manage and some patients will ultimately require surgery. There have been previous studies on the success of revision ureteroneocystostomy in treating reflux but no data on the reduction in hospitalizations associated with recurrent infections following the procedure. Limitations of this study are the small cohort size, retrospective nature, multi-surgeon study, and inherent selection bias due to evaluation of only surgical patients.

CONCLUSION

Revision ureteroneocystostomy can limit the negative consequences of recurrent graft infections with reduction in hospitalization days and improved hospitalization rates due to urinary tract infections. The reduction in hospitalizations can greatly improve the cost of care along with quality of life for transplant patients and should be strongly considered in children with symptomatic vesicoureteral reflux who have failed conservative therapy.

Role of Contrast-Enhanced Voiding Urosonography in the Evaluation of Renal Transplant Reflux - Comparison with Voiding Cystourethrography and a New Classification

Vesicoureteral reflux (VUR) is a common urological complication in renal transplant patients.

THE AIM

of this study is to evaluate the performance of contrast-enhanced voiding urosonography (CEvUS) in the diagnosis and classification of reflux into the renal allograft, to evaluate and classify VUR into the allograft using voiding cystourethrography (VCUG) and CEvUS, to compare the two methods, and to propose a new classification of reflux into the allograft based on CEvUS and VCUG assessment, in line with the international reflux grading system.

MATERIALS AND METHODS

 From January 2017 to July 2019, 84 kidney transplant patients were enrolled. All patients underwent VCUG and CEvUS.

RESULTS

 In 76 cases there was agreement between VCUG and CEvUS (90 %) (Kappa = 0.7). The sensitivity of CEvUS using VCUG as the gold standard was 90 %, and the specificity was 92 %. Of the 7 cases diagnosed by VCUG and not by CEvUS, 6 were grade 1 and 1 was grade 2.

CONCLUSION

 Transplant patients with reflux symptoms should undergo CEvUS. If the outcome is negative, VCUG should be performed. The classification that we propose is better suited to describe VUR in transplant patients, because it is simpler and takes into account whether reflux occurs not only during urination but also when the bladder is relaxed.

Pearls and Pitfalls in Pediatric Kidney Transplantation After 5 Decades

Worldwide, over 1,300 pediatric kidney transplantations are performed every year. Since the first transplantation in 1959, healthcare has evolved dramatically. Pre-emptive transplantations with grafts from living donors have become more common. Despite a subsequent improvement in graft survival, there are still challenges to face. This study attempts to summarize how our understanding of pediatric kidney transplantation has developed and improved since its beginnings, whilst also highlighting those areas where future research should concentrate in order to help resolve as yet unanswered questions. Existing literature was compared to our own data of 411 single-center pediatric kidney transplantations between 1968 and 2020, in order to find discrepancies and allow identification of future challenges. Important issues for future care are innovations in immunosuppressive medication, improving medication adherence, careful donor selection with regard to characteristics of both donor and recipient, improvement of surgical techniques and increased attention for lower urinary tract dysfunction and voiding behavior in all patients.

A systematic review of outcomes of Deflux® treatment for vesicoureteral reflux following pediatric renal transplantation

INTRODUCTION

Vesicoureteral reflux (VUR) after renal transplant in the pediatric population may be associated with an increased incidence of urinary tract infection (UTIs) leading to increased morbidity, including graft dysfunction and graft loss. The non-orthotopic location of the transplanted ureter, and lack of submucosal tunnel may pose challenges in correcting the VUR using endoscopic injection techniques. Herein we report the results of a systematic review evaluating the outcomes of endoscopic treatment of VUR using Deflux® in this population.

METHODS

Pubmed and Embase databases were searched from October 2001 to April 2019. Full-text English articles involving patients less than 18 years old at the time of transplant, with a diagnosis of VUR post-transplantation, who underwent Deflux® treatment were included. Figure 1 outlines our PRISMA-compliant search strategy.

RESULTS

We found 6 eligible studies describing Deflux® treatment outcomes in 67 pediatric patients with post-transplant VUR where voiding cystourethrogram (VCUG) confirmed the diagnosis and resolution of VUR. The mean success rate was 36.8%. Ureteral obstruction occurred in 7/67 cases (10.4%). In all these 7 cases of obstruction, ureteric stenting was the initial management, but was only successful in 1 patient. Open ureteroneocystostomy (UNC) was performed in 4/7 cases, while 2/7 were managed expectantly (unknown outcomes). Persistent VUR with UTI despite Deflux® were reported in 20 out of 67 cases. Of these, 7 were managed with prophylactic antibiotics, and 13 with UNC. Success rates were consistently low for UNC after failed Deflux® in comparison to redo UNC in transplant ureters without prior injection.

CONCLUSION

Low success rates are seen following injection techniques for VUR after pediatric renal transplant. Although an appealing option, Deflux® may prove counterintuitive due to the high rate of obstruction and suboptimal results if open reimplantation is required. A multi-institutional prospective study with a larger population size may further elucidate these results.

Increasing bladder capacity and vesicoureteral reflux in pediatric kidney transplant patients

OBJECTIVES

To investigate the frequency of vesicoureteral reflux, and the relationship of pretransplant decreased bladder capacity and post-transplant vesicoureteral reflux in children undergoing kidney transplantation.

METHODS

A voiding cystourethrography was carried out in 172 pediatric kidney transplantation recipients before, and 4 months after, transplantation to evaluate bladder capacity and vesicoureteral reflux. The correlation of post-transplant vesicoureteral reflux with pretransplant bladder capacity, vesicoureteral reflux in the native kidney and the method of ureteral reimplantation (intravesical/extravesical) was analyzed. Atrophic bladder was defined as having ≤50% functional bladder capacity (age in years + 2) × 25 (mL) or ≤150 mL in patients aged >10 years.

RESULTS

Bladder capacity increased remarkably after transplantation in both post-transplant vesicoureteral reflux- group (from 180 to 253 mL) and vesicoureteral reflux+ group (from 82 to 171 mL). Voiding cystourethrography showed vesicoureteral reflux in 12 cases of kidney transplantation (7%; grade 1: 2, grade 2: 3, grade 3: 7). Pretransplant atrophic bladder was an independent risk factor of post-transplant vesicoureteral reflux (P = 0.004, hazard ratio 9.5). There was no difference in renal function between the vesicoureteral reflux- group and vesicoureteral reflux+ group at 4 months to 5 years post-transplantation.

CONCLUSIONS

Pretransplant atrophic bladder is a risk factor of post-transplant vesicoureteral reflux in pediatric patients. However, bladder capacity can remarkably increase after transplantation, and kidney function in the post-transplant vesicoureteral reflux+ group is stable.

When does vesicoureteral reflux in pediatric kidney transplant patients need treatment?

PURPOSE

The treatment of VUR in children with UTI has changed significantly, due to studies showing that antibiotic prophylaxis does not decrease renal scarring. As children with kidney transplants are at higher risk for UTI, we investigated if select patients with renal transplant VUR could be managed without surgery.

MATERIALS AND METHODS

A total of 18 patients with VUR into their renal grafts were identified, and 319 patients underwent transplantation from 2006 to 2016. The cause for the detection of the VUR, treatment, and graft function was reviewed.

RESULTS

Six boys and 12 girls were identified, 13 of whom had grade 3 or 4 VUR into the renal graft. Nine patients presented with hydronephrosis or abnormal renal biopsy: eight were successfully managed with antibiotic prophylaxis and bladder training, one developed UTI and underwent Dx/HA subureteric injection. Nine patients presented with recurrent febrile UTI, only one was successfully managed without surgery. Only 2 of 9 (22%) patients who underwent Dx/HA injection had resolution of their reflux. Of the remaining seven, five required open ureteral reimplantation (two for obstruction), one lost the graft due to rejection, and one had significant hydronephrosis. eGFR was similar between the hydronephrosis, UTI, and abnormal renal biopsy groups at all times.

CONCLUSION

Patients with transplant VUR and recurrent febrile UTI are more likely to require surgical therapy, but the complication and failure rate for Dx/HA injection is significant. Patients with transplant VUR without febrile UTI can be successfully managed with bladder training and temporary antibiotic prophylaxis.

Urologic Evaluation and Management of Pediatric Kidney Transplant Patients

Urologic causes of end-stage renal disease are estimated between 25% and 40% of causes. The goal of renal transplantation in chronic kidney disease patients is to provide renal replacement therapy with less morbidity, better quality of life, and improved overall survival compared with dialysis. A patient's urologic history can be a significant source of problems related to infections, recurrence of disease, and surgical complications. Many of the urologic risks are modifiable. Proper evaluation and management can mitigate the potential problems after transplantation, and these patients with complex urologic problems are seen to have similar graft function outcomes.

Renal function outcomes in pediatric patients with symptomatic reflux into the transplanted kidney treated with redo ureteroneocystostomy

INTRODUCTION

Asymptomatic post-renal transplant reflux is common but only 5-10% patients are diagnosed with vesico-ureteral reflux in the setting of post-transplant febrile urinary tract infections, requiring redo ureteroneocystostomy (redo-UNC). Here we report the renal function outcomes of 37 such patients, stratified by lower urinary tract (LUT) status.

OBJECTIVE

We hypothesized that those with pre-transplant LUT dysfunction would have lower glomerular filtration rate (GFR) on follow-up.

STUDY DESIGN

Using procedure codes, 37 patients who underwent renal transplant followed by redo-UNC for transplant reflux at our institution between 1991 and 2014 were identified. Patient characteristics and GFR levels from four different time points were recorded. Comparisons were made between those with and without LUT dysfunction, using Fisher's exact, Wilcoxon rank sum, or signed-rank tests. Generalized estimating equations were constructed to account for the clustered nature of GFR within each LUT group and to assess their change over time.

RESULTS

Twelve patients (32%) had pre-transplant LUT dysfunction. The proportion of males in this group was significantly higher (75% vs. 32%, p = 0.032), and there was no statistical difference towards presenting earlier with post-transplant reflux (1.4 vs. 2.3 years, p = 0.087). After an average of 4.9 years, the median GFRs were similar between the two groups (53 mg/dL vs. 58 mg/dL, p = 0.936). There was no significant difference in GFR at this last follow-up time point in patients with and without LUT dysfunction.

DISCUSSION

Vesicoureteral reflux in the setting of renal transplantation is common and doesn't often require repair. In our series, we found that those with LUT dysfunction did not present statistically sooner with symptomatic transplant reflux. Longer-term follow-up did show a decline in GFR but did not reveal a difference in GFR in patients' with and without LUT dysfunction.

CONCLUSIONS

Pediatric post-transplant GFR after open redo ureteral reimplant decreases over time in similar fashion in patients with symptomatic reflux regardless of whether they have LUT dysfunction or normal anatomy. Vigilance should apply to the recognition, treatment, and follow-up of all symptomatic transplant reflux regardless of LUT status.

Imaging in pediatric renal transplantation

Renal transplantation is the therapy of choice in children with ESKD. Radiological investigations are required in both pre- and post-transplant assessment, although there is paucity of both consensus-based statements and evidence-based imaging guidelines in pediatric renal transplantation. The phases of pediatric ESKD management that require imaging are pretransplantation recipient assessment and post-transplantation surveillance for detection of potential complications. We present suggestions for imaging algorithms for both pre- and post-transplant assessment in pediatric renal transplant recipients.

Comparison of Surgical Correction Techniques for Post-Renal Transplantation Vesicoureteral Reflux

BACKGROUND

Symptomatic urinary tract infection (UTI) after renal transplantation (RT) is an important morbidity in transplant recipients and may cause pyelonephritis and sepsis. Surgical correction of high-grade vesicoureteral reflux (VUR) after RT is suggested, performing ureteral reimplantation or pyelo-ureteral/uretero-ureteral anastomosis. Recently, extravesical seromuscular tunnel lengthening techniques have been reported with favorable results and low complication rates.

METHODS

We retrospectively reviewed the charts of 38 patients with post-transplantation VUR who underwent reflux correction surgery. Patient characteristics were analyzed to compare our extravesical seromuscular tunnel lengthening technique with uretero-ureteral and pyelo-ureteral anastomosis techniques.

RESULTS

Twenty patients were treated with the extravesical approach (group I) and 18 patients by pyelo-ureteral or uretero-ureteral anastomosis with the use of native ureter (group II). Mean operative time was significantly shorter in group I than in group II (64.8 vs 110.1 min; P < .05), and mean duration of hospital stay after the operation also was shorter in group I (1.5 vs 5.1 d; P < .05). We determined persistent VUR in postoperative voiding cystouretrography in 2 patients (10%) in group I, but there was regression in VUR grades of all of the patients. There was no significant difference in postoperative number of UTI episodes and serum creatinine levels between the 2 groups.

CONCLUSIONS

Extravesical seromuscular tunnel lengthening is an effective and safe technique for post-transplantation VUR management.

Endoscopic antireflux surgery leading to obstruction in pediatric renal transplant patients

To describe a multicenter experience with management of ureteral obstruction after injection of Dx/HA for VUR in pediatric renal transplant patients. The records of all pediatric renal transplant patients who underwent Dx/HA injection for VUR and had subsequent obstruction were identified, and the management and outcomes were reviewed. Follow-up ranged from 1 to 10 years. There were four patients identified, all of whom had a history of rising creatinine, recurrent UTI, and increasing hydronephrosis which led to the diagnosis of high-grade VUR. Obstruction was diagnosed within 24-72 hours after injection in three patients. One patient was asymptomatic, and rising creatinine and hydronephrosis were noted 1 month after injection. One patient was managed expectantly, while three patients underwent ureteral stent placement. After the stent was removed, one patient went on to open reimplant due to delayed obstruction, the second patient with voiding dysfunction is currently managed with an indwelling ureteral stent and may require further definitive surgery, the third patient recovered, and the fourth is being observed. Our cases illustrate that despite initial successful management of the obstruction in some, delayed obstruction is possible and may necessitate open reimplant. It is imperative that these patients have close follow-up after Dx/HA.

Urological complications following kidney transplantation in pediatric age: A single-center experience

Surgical complications during kidney transplantation can seriously affect renal outcomes. We assess occurrence, risk factors, and results of all urological complications in a series of renal transplants in a single center. Children who underwent renal transplant between January 2008 and December 2014 were retrospectively evaluated. Postoperative urological complications were reviewed. Demographic details, cause of ESRD, donor type, and surgical procedures at transplant were analyzed. For statistical analysis, the chi-square test or Fisher's exact test were used as appropriate. One hundred and twenty-one kidney transplants were performed in 117 children (median age 12 yr). Sixty-two of 121 (53%) had an underlying urological malformation. At a median follow-up of three yr, 28 urological complications were recorded (23%): 12 lymphocele (10%), 10 ureteral obstruction (8%), three urinary leakage (2.5%), two symptomatic VUR (1.7%), and one hydropyonephrosis. When lymphocele was excluded, the complication incidence rate dropped to 13%. Ureteral obstruction mostly occurred late after transplant (more than six months). Presence of urological malformation was the only factor related to increased occurrence of urological complication (p = 0.007) and, in particular, ureteral obstruction (p = 0.018). Children with urological malformations presented a statistically significant risk of developing urological complications after kidney transplantation, ureteral obstruction being the most common complication.

Favorable Outcomes of Renal Transplant in Children With Abnormal Lower Urinary Tract

OBJECTIVES

Chronic kidney disease caused by lower urinary tract abnormalities is a significant complication in pediatric care. Although there are conflicting reports about clinical outcomes in the past, favorable outcomes have been reported in recent years. Despite this, many centers still refrain from performing renal transplant in these patients. Here, we compared clinical outcomes of renal transplant recipients with and without lower urinary tract abnormalities.

MATERIALS AND METHODS

Our study included 71 renal transplant recipients who were divided into 3 groups: 17 patients with abnormal lower urinary tracts having vesicoureteral reflux (group 1), 7 patients with abnormal lower urinary tracts having bladder dysfunction (group 2), and 47 patients with anatomically and functionally normal lower urinary tracts (group 3). We retrospectively compared demographic features, clinical course, graft survival, pre- and posttransplant incidence of urinary tract infections, and final graft function among the groups.

RESULTS

There were no statistically significant differences among groups regarding median age at time of transplant, graft survival, median creatinine level, and median glomerular filtration rate (P > .05). Significant differences were shown in incidence of urinary tract infections between patients in groups 1 and 2 (abnormal lower urinary tracts) and group 3 (normal lower urinary tracts) before transplant (P < .05). Although frequency of urinary tract infections in groups 1 and 2 were moderately higher than shown in group 3 after transplant, this difference was not statistically significant.

CONCLUSIONS

Although the children with abnormal lower urinary tracts had slightly higher incidence of urinary tract infections, there were no differences between patients with abnormal and normal lower urinary tracts regarding allograft survival and function. In addition, proper follow-up of patients before and after transplant, based on our experience, should include educating patients and their parents about potential complications after transplant for the best outcome of renal transplant.

A nipple-valve technique for ureteroneocystostomy in pediatric kidney transplantation

The ureteroneocystostomy in kidney transplantation can be performed with a variety of techniques. Over a 20-yr period, we utilized a technique of nipple-valve ureteroneocystostomy for the pediatric kidney transplants performed at our institution. The distal ureter is everted upon itself and anchored in place with four interrupted sutures to create a nipple valve, which is then inserted into the bladder and sewn mucosa-to-mucosa with the same sutures. The muscularis layer is closed around the ureter without tunneling and without routine ureteral stenting. After 109 transplants, patient survival was 97.2, 97.2, and 86.9% at one, five, and 10 yr, respectively. Graft survival was 91.7, 71.7, and 53.9% at one, five, and 10 yr, respectively. The most common cause of graft loss was acute or chronic rejection, seen in 75% of those experiencing graft loss. Two patients (1.8%) developed pyelonephritis in the transplanted kidney. Nipple-valve ureteroneocystostomy in pediatric kidney transplantation is a safe and simple method for performing the ureterovesical anastomosis with a low rate of pyelonephritis after transplantation.

Ultrasonographic evaluation of the renal transplant

Ultrasonography is an excellent tool for evaluation of the renal transplant in the immediate postoperative period and for long-term follow-up. In this article, normal imaging findings and complications of renal transplantations are described. Disease processes are divided into vascular, perinephric, urologic and collecting system, and parenchymal abnormalities. Attention is paid to the time of occurrence of each complication, classic imaging findings, and potential pitfalls.

Renal relevant radiology: imaging in kidney transplantation

Kidney transplantation can be associated with various complications that vary from vascular complications to urologic disorders to immunologic adverse effects. In evaluating the recipient with graft dysfunction, clinicians can choose among several imaging modalities, including ultrasonography, nuclear medicine studies, computed tomography, and magnetic resonance imaging. This review discusses the evaluation of the kidney transplant recipient using these imaging procedures, emphasizing the clinical diagnostic utility and role of each modality. A kidney biopsy is often required as a gold standard for diagnostic purposes. However, because of the inherent risks of a kidney biopsy, noninvasive imaging in diagnosing causes of graft dysfunction is a highly desired tool used and needed by the transplant community. Because the diagnostic accuracy varies depending on the time course and nature of the transplant-related complication, this review also addresses the advantages and limitations of each modality. The recent advances in kidney transplant imaging techniques and their clinical implications are also discussed.

Lich-gregoir procedure in treatment of the vesicoureteral reflux

Vesicoureteral reflux is a major problem in childhood affecting 1% of all children. There are various surgical methods for vesicoureteral reflux treatment. Current study evaluates effectiveness and success rate of the Lich-gregoir procedure in treatment of the vesicoureteral reflux. In a descriptive-analytical study, 32 children with 47 reflux unit underwent Lich-gregoir anti-reflux procedure in Imam Reza and Amir-al-Momenin Hospitals, Tabriz between March 2008 and August 2011. Surgery outcome and success rate, sonographic findings and complications rate were recorded in follow-up. Patients mean age was 5.85 +/- 3.81 years. 28.1% were male and 71.9% were female. Reflux was unilateral in 53.1% and bilateral in 46.9%. Vesicoureteral reflux grade I to V was in one, 1, 13, 22 and ten patients, respectively. Voiding Cystourethrogram (VCUG) findings were abnormal in all cases before operation. Surgery success rate in first 6 months was 95.7% and was 100% in 8 months after operation. Hydronephrosis disappeared after operation in all cases. Complication occurred in 2 cases (6.25%) with bilateral reflux including urinary intention and lymphocele. Lich-gregoir anti-reflux procedure technique is accompanied with higher success rate, low complication and hydronephrosis improvement and is an appropriate treatment for vesicoureteral reflux in children.

Value of routine voiding cystourethrography after renal transplantation

The impact of vesicoureteral reflux (VUR) on renal allograft outcomes is debatable, with small cohort studies reporting controversial results. The objective of this retrospective study was to evaluate long-term clinical effects of early VUR in a large cohort of kidney transplant patients. Posttransplantation voiding cystourethrography was used to evaluate 646 consecutive kidney transplant recipients before discharge. The study endpoints included VUR grade, death-censored graft or patient survival, renal function, proteinuria and occurrence of urinary tract infections (UTIs). Of the 646 recipients, 263 (40.7%) were diagnosed with VUR. VUR grade II was most common (19.8%), followed by grades III (10.2%), I (7.9%) and IV (2.8%). VUR was less common in transplantations performed by experienced compared to inexperienced surgeons (36% vs. 48%; p = 0.004). VUR did not affect death-censored graft or patient survival and was not associated with proteinuria or occurrence of UTIs. Patients with VUR had a lower eGFR at 1 year after transplantation than did patients without VUR (60 vs. 52 mL/min/1.73 m(2) ; p = 0.02), although this difference was not observed at 3 and 5 years after transplantation. We conclude that early VUR, a common finding among renal transplant patients, may not have a meaningful impact on long-term transplant outcomes.

The modified Barry technique to prevent vesicoureteric reflux in paediatric renal transplant recipients: initial recipient outcomes

OBJECTIVE

We present the initial clinical results of the 'modified Barry technique' for the prevention of VUR in paediatric renal transplant grafts. Ours is the only centre in the UK using this technique, as confirmed in a questionnaire developed in our department.

PATIENTS AND METHODS

We retrospectively analysed data of 15 paediatric renal transplant patients (operated June 2006-November 2009) who had their vesicoureteric anastomosis performed using the modified Barry technique with a 2-cm submucosal anti-reflux tunnel. The original Barry technique involved the creation of a 4-cm tunnel; this was modified by us to reduce the risk of ureteric stenosis.

RESULTS

At a median follow up of 23.7 months (6.3-39.4), the incidence of VUR was 7% (1/15). There was no evidence of postoperative urological complications, such as urinary leak, primary ureteric obstruction including anastomotic stricture/stenosis, transplant graft renal calculi and chronic rejection. At current follow up, graft and patient survival are 100%.

CONCLUSION

With the introduction of the modified Barry technique, the incidence of VUR in our series fell 10-fold to 7%, compared with our earlier study (P<0.0001), without any urological complications. Although the initial results are encouraging, larger patient numbers and longer follow up are required to validate this technique further.

Correlations between pretransplant dialysis duration, bladder capacity, and prevalence of vesicoureteral reflux to the graft

BACKGROUND

Urinary bladder capacity is reduced in patients undergoing long-term dialysis, which may increase the risk of vesicoureteral reflux (VUR) to a transplanted kidney. This study investigated the correlations between dialysis duration, pretransplant and posttransplant bladder capacity, and prevalence of VUR to the graft.

METHODS

Voiding cystography was performed in 101 adult renal transplant recipients without neurogenic disorders immediately before and 1 year after transplantation to evaluate bladder capacity and VUR. Nonstented extravesical antireflux ureteroneocystostomy was performed in all patients.

RESULTS

The median dialysis duration and pretransplant bladder capacity were 32 months (range 1-426 months) and 120 mL (range 15-450 mL), and 21 patients (20.8%) underwent dialysis for more than 120 months, and 30 patients (29.7%) had a pretransplant bladder capacity of less than 80 mL. Dialysis duration was correlated with pretransplant bladder capacity (R=0.466, P<0.001). Bladder capacity expanded more than 6-fold from pretransplantation to posttransplantation, and all recipients had a bladder capacity greater than 150 mL at 1 year posttransplantation. Thirty patients had VUR to the graft. Dialysis duration longer than 60 months (P=0.021) and pretransplant bladder capacity of less than 130 mL (P=0.024) were associated with VUR. VUR was associated with lower graft function.

CONCLUSIONS

Although bladder capacity decreased because of long-term dialysis, it exceeded 150 mL at 1 year posttransplantation. A small bladder can be used in renal transplantation, but it may increase the risk of VUR.

[Urinary tract infections after kidney transplantation: Essen algorithm for calculated antibiotic treatment]

Urinary tract infections are the most common infection early after transplantation and can affect long-term graft function. Any urinary tract infection in renal transplant recipients should be seen as "complex" with regard to consequences for diagnosis and therapy. The increase in resistance to anti-infective agents seen among uropathogens is one of the central therapeutic problems. This means for routine clinical practice that contact isolation precautions should be consistently implemented for affected patients and the duration of introducing urinary tract instruments should be minimized. Detection of pyuria and urine cultures are required to confirm infection, to identify the corresponding pathogen, and to review the antibiotic therapy.The "Essen algorithm for calculated antibiotic treatment of urinary tract infections in renal transplant patients" takes into consideration the high incidence of Gram-negative pathogens in general and the increased incidence of enterococci in the early phase after transplantation. Within the first 2 months after transplantation quinolones should be used and later cephalosporins. In case of urosepsis, calculated antibiotic therapy should cover problematic Gram-negative pathogens such as pseudomonades. The calculated antibiotic therapy should be administered intravenously in severe infections. In any case the local and regional antibiotic susceptibility should be taken into account when deciding on the calculated antibiotic therapy.

A novel surgical technique for management of vesicoureteral reflux following kidney transplantation: prospective study of 12 cases

The incidence of vesicoureteral reflux (VUR) varies between 10% and 80% of transplanted kidneys. In cases of failure of endoscopic treatment or recurrent urinary tract infections, surgical correction is proposed by ureteral reimplantation or pyeloureteral anastomosis using the native ureter. The aim of this study was to assess the results of a technique that increases the submucosal length of the ureter without a ureterovesical reimplantation. We treated 12 patients with VUR in the transplanted kidney by open surgery. Retrograde cystography showed resolution of reflux in all the patients. Our technique has the advantage of avoiding ureteral dissection thereby avoiding its devascularization and no invasion of the bladder mucosa.

Should a complex uropathy be a contraindication for renal transplantation in children?

BACKGROUND

Anatomic and functional disorders of the lower urinary tract represent up to 40% of the causes of renal failure in children. Several centers avoid renal transplantation in these patients because of the high risk of complications and lower graft survival. The aim of this work was to determine the frequency of urinary tract abnormalities (UTAs) among our pediatric series, and to compare the frequency of complications, function, and long-term graft survival among patients without versus with UTA.

METHODS

This single-center, retrospective study compared outcomes between pediatric recipients with versus without UTA. We analyzed demographic features, etiology, pretransplant protocol, urinary tract rehabilitation, incidence of complications, rejection events, as well as graft function and survival.

RESULTS

Among 328 pediatric cases performed between 1998 and 2008, we excluded nine patients due to incomplete medical records, analyzing 319 procedures in 312 patients. Sixty-seven patients (21%) had UTA. The average age, weight, and height at the time of grafting were significantly lower in the urologic group: 11.1 versus 12.6 years, 28.8 versus 34.4 kg; 125.4 versus 138.4 cm, respectively. There were significantly higher frequencies of a transperitoneal approach and vena cavae and aortic anastomoses among patients with UTA (P < .001), posing a greater technical challenge in this population. No differences in creatinine levels were observed at 0.5, 1, 2, 5, and 10 years: 1.3 versus 1.6 at 5 years, and 1.4 versus 1.5 at 8 years. Urologic complications, including urinary tract infections (UTIs), occurred among 80.6% of patients with UTA versus 42.1% in the non-UTA group (P < .001). UTIs appeared predominantly in patients with UTA (62.7% vs 35.3%, P < .001), representing a 2.7-fold risk compared with those children transplanted for other reasons. Rejection incidence was similar in both groups (49.8%). There was no significant difference in 5-y (89.8% vs 85%) or 10-year (83% vs 67%) graft survivals between the groups (P = .162).

CONCLUSION

Our results demonstrated that with proper interdisciplinary care, graft and patient survivals of pediatric recipients with UTAs were not affected; therefore, these patients should not be rejected for transplantation.

Urological issues in pediatric renal transplantation

PURPOSE OF REVIEW

The pediatric patient with end-stage renal disease provides a great opportunity for the involvement of the pediatric urologist because of the high incidence of associated urologic anomalies.

RECENT FINDINGS

Renal transplant remains the procedure of choice in the child with end-stage renal disease. The durability of survival of the graft is impacted by successful management of the genitourinary tract.

SUMMARY

Preoperative, intraoperative, and postoperative evaluation is critical for the child with associated urologic disease and end-stage renal disease. Early and appropriate management may stabilize renal function and prolong the time to transplant. Due to the relatively long life expectancy of children compared with adults with end-stage renal disease, appropriate management may be of benefit to avoid the morbidity associated with renal replacement therapy. In certain children, the appropriate management and reconstruction of the genitourinary tract may allow for a planned and preemptive renal transplant, thus avoiding dialysis.