Endoscopic antireflux surgery leading to obstruction in pediatric renal transplant patients

The Extended Utilization of Bulking Agents in Pediatric Urology

PURPOSE OF REVIEW

Traditional surgical management for urinary incontinence and vesicoureteral reflux often requires complex reconstructive surgery and extended hospitalizations. Since the introduction of endoscopic bulking agents in 1973, there has been increasing interest in the use of endoscopic injection (EI) and bulking for the treatment of a variety of pediatric urologic disorders. The purpose of this review is to summarize the most recent literature addressing the use of bulking agents in pediatric urology.

RECENT FINDINGS

The most recent literature has focused primarily on the use of EI of bulking agents at the bladder neck for the treatment of urinary incontinence. Other uses of EI of bulking agents has focused on the treatment of vesicoureteral reflux (VUR) in patients with anatomic abnormalities or treatment of incontinence catheterizable channels. The development of advanced techniques for endoscopic injection along with safe, stable bulking agents has allowed for the treatment of a variety of urologic conditions. This minimally invasive procedure offers an additional tool for the pediatric urologist's armamentarium in the treatment of urinary incontinence and VUR.

Does STING failure affect short-term graft functions in renal transplant patients: a single-center study

PURPOSE

The aim of the present study was to evaluate outcomes of symptomatic VUR treatment in transplant patients, compare open and endoscopic approaches in terms of graft functions, success rates, complications and recurrent UTIs.

METHODS

67 patients who undergone only STING and STING followed redo UNC due to symptomatic VUR after kidney transplantation were included into the investigation. Patients who had lower urinary tract dysfunctions were excluded from the trial. For 67 patients, baseline and before final surgery and 3rd month creatinine and GFR levels were recorded. Twenty-six of those 67 patients had redo UNC due to failed STING. The data of those patients were compared with the remaining 41 patients who had only STING.

RESULTS

In both groups no statistically significant variations in serum creatinine and GFR levels were detected during follow-up (p > 0.05). Serum levels after STING and in the 3rd month of redo UNC were compared. Although variation was observed in serum creatinine levels and in GFR levels, was not statistically significant (p: 0.59 and p: 0.23). The success rate of STING was %61.1 in 67 patients, and was not significantly different when three VUR grade groups (Grade 3 n:17, Grade 4 n:24, Grade 5 n:36) were compared (p > 0.05).

CONCLUSION

The present study revealed that subureteral endoscopic injection is cost effective and safe for the first-line treatment due to its minimally invasive nature, does not cause delay which leads to deterioration of graft functions. Redo-UNC has acceptable morbidity and complication rates, should be considered when STING is failed.

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.

Treatment of Vesicoureteral Reflux Detected After Renal Transplant in Pediatric Patients: A Single-Center Experience

OBJECTIVE

In children who undergo renal transplant, vesicoureteral reflux on the transplanted kidney is a serious complication that may result in organ loss. In this study, we aimed to evaluate the results of endoscopic and open surgical techniques in the treatment of patients with recurrent urinary tract infections and vesicoureteral reflux after renal transplant.

MATERIAL AND METHODS

The files of pediatric patients who underwent renal transplant in our hospital between January 2016 and January 2019 were evaluated retrospectively. In this single-center analysis, we investigated the incidence of vesicoureteral reflux in the kidney transplant recipients and the results of various approaches to treat it.

RESULTS

Eighty pediatric patients underwent renal transplant between January 2016 and January 2019. Fourteen of those patients (17.5%, 7 female and 7 male) were diagnosed with vesicoureteral reflux in the postoperative period. Twelve of 14 patients received endoscopic injections as the first treatment. Clinical or radiological success was achieved in 5 patients (5 of 15 injection treatments, 33%); in 4 patients (4/12, 33.3%) success was after the first endoscopic injection treatment, and in 1 patient (1/3, 33.3%) success was after the second injection. Meanwhile, clinical or radiological success was achieved in 6 of 7 patients who underwent redo ureteroneocystostomy (6/7, 85.7%).

CONCLUSION

Although symptomatic vesicoureteral reflux after renal transplant is rare in pediatric patients, it is an important cause of morbidity as it requires recurrent surgical procedures. Although endoscopic treatment is safe and minimally invasive, the success rate is lower than expected, and redo of ureteral reimplant may be required in most cases.

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.

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.

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.