Controversy in renal transplantation: antireflux versus non-antireflux ureteroneocystostomy

Allograft Vesicoureteral Reflux after Kidney Transplantation

Allograft vesicoureteral reflux (VUR) is a leading urological complication of kidney transplantation. Despite the relatively high incidence, there is a lack of consensus regarding VUR risk factors, impact on renal function, and management. Dialysis vintage and atrophic bladder have been recognized as the most relevant recipient-related determinants of post-transplant VUR, whilst possible relationships with sex, age, and ureteral implantation technique remain debated. Clinical manifestations vary from an asymptomatic condition to persistent or recurrent urinary tract infections (UTIs). Voiding cystourethrography is widely accepted as the gold standard diagnostic modality, and the reflux is generally graded following the International Reflux Study Committee Scale. Long-term transplant outcomes of recipients with asymptomatic grade I-III VUR are yet to be clarified. On the contrary, available data suggest that symptomatic grade IV-V VUR may lead to progressive allograft dysfunction and premature transplant loss. Therapeutic options include watchful waiting, prolonged antibiotic suppression, sub-mucosal endoscopic injection of dextranomer/hyaluronic acid copolymer at the site of the ureteral anastomosis, and surgery. Indication for specific treatments depends on recipient’s characteristics (age, frailty, compliance with antibiotics), renal function (serum creatinine concentration < 2.5 vs. ≥ 2.5 mg/dL), severity of UTIs, and VUR grading (grade I-III vs. IV-V). Current evidence supporting surgical referral over more conservative strategies is weak. Therefore, a tailored approach should be preferred. Properly designed studies, with adequate sample size and follow-up, are warranted to clarify those unresolved issues.

Robotic Surgery for the Reconstruction of Transplant Ureteral Strictures

OBJECTIVE

To demonstrate the feasibility and success of a robotic approach to reconstruction of ureterovesical anastomotic strictures in kidney transplants.

MATERIALS AND METHODS

Between November 2017 and December 2019, a total of 5 patients with transplant ureteral stricture were identified and treated with robot assisted laparoscopic repair. All patients were confirmed to have ureteral stricture with a preoperative antegrade nephrostogram through their nephrostomy tube and cystogram. The patients demographics, ureteral characteristics, type of procedure, and outcomes are reported.

RESULTS

All patients were diagnosed after evaluation for renal deterioration. The average age of the patients was 49 years old. The average stricture length was 2.5 cm, and the location was variable, though more commonly in the distal ureter. Three patients required a pyelo-vesicostomy, while 2 required a ureteroneocystostomy. The mean length of stay was 2.2 days. Average follow-up was 97 days, with all 5 patients having successful outcomes, no strictures or delayed leaks were identified. There were no wound infections or readmissions within 30 days.

CONCLUSION

Though a complex repair, the robot-assisted approach to transplant ureter reconstruction using either an end to side neoureterocystotomy or direct pyelo-vesicotomy is technically feasible and successful. Given the many advantages inherent in comparison to an open approach, the robotic repair offers significant advantages to both the patient and the surgeon who is experienced with robotic surgery and reconstructive principles.

Contemporary management of ureteral strictures

Ureteral stricture disease is a luminal narrowing of the ureter leading to functional obstruction of the kidney. Treatment of strictures is mandatory to preserve and protect renal function. In recent times, the surgical management of ureteral strictures has evolved from open repair to include laparoscopic, robotic and interventional techniques. Prompt diagnosis and early first line intervention to limit obstructive complications remains the cornerstone of successful treatment. In this article, we discuss minimally invasive, endo-urological and open approaches to the repair of ureteral strictures. Open surgical repair and endoscopic techniques have traditionally been employed with varying degrees of success. The advent of laparoscopic and robotic approaches has reduced morbidity, improved cosmesis and shortened recovery time, with results that are beginning to mirror and in some cases surpass more traditional approaches.

Level of evidence: Not applicable for this multicentre audit.

Ureterovesical anastomotic techniques for kidney transplantation: a systematic review and meta-analysis

No consensus exists about which ureterovesical anastomosis technique to use for kidney transplantation. The aim of this systematic review was to compare the existing techniques in relation to the risk of urological complications. All studies that compared ureterovesical anastomotic techniques in kidney transplantation were included. Study endpoints were urinary leakage, ureteral stricture, vesicoureteral reflux and hematuria. Subanalyses of stented and nonstented techniques were performed. Two randomized clinical trials and 24 observational studies were included. Meta-analyses were performed on the Lich-Gregoir (LG) versus Politano-Leadbetter (PL) techniques and LG versus U-stitch (U) techniques. Compared with the PL technique, the LG technique had a significantly lower prevalence of urinary leakage (risk ratio (RR): 0.47, 95% confidence interval (CI): 0.30 to 0.75) and a significantly lower prevalence of hematuria when compared with both PL and U techniques (RR: 0.28, 95% CI: 0.16 to 0.49 and RR: 0.23, 95% CI: 0.11 to 0.50, respectively), regardless of ureteral stenting. There was no difference in the prevalence of ureteral strictures or vesicoureteral reflux between the various techniques. Of the three most frequently used ureterovesical anastomotic techniques, the LG technique results in fewer urological complications than the PL and U techniques.

Feasibility and outcomes of ureteroureterostomy and extravesical ureteroneocystostomy as part of radical surgery for infiltrating gynecologic disease

OBJECTIVE

Abdominopelvic infiltrative disease may require aggressive surgical procedures. This study reports on our experience with distal ureterectomy, ureteroureterostomy, and extravesical ureteroneocystostomy as part of radical surgery for infiltrating gynecologic disease.

PATIENTS AND METHODS

Twenty-one women required surgery to the distal ureter at the Queensland Centre for Gynecological Cancer, Australia, from January 2006 to September 2012. Details of the patient's history, operation record, inpatient notes, and follow-up data were obtained through chart review.

RESULTS

Patients' median age was 57.8 ± 14.7 years (range, 30-80 years). Seventeen patients had gynecologic cancer. Mean operating time was 3.9 ± 0.9 hours (range, 2.5-5.5 hours). Restoration of continuity was achieved through extravesical ureteroneocystostomy and ureteroureterostomy in 18 and 3 patients, respectively. Boari flap was used in 3 patients, and psoas hitch was the technique chosen in 11 patients. Urinary tract infection was the most common clinical adverse event. Albeit clinically irrelevant, 38% of the patients showed structural renal tract changes postoperatively.

CONCLUSIONS

To achieve maximal surgical radicalness, resection of the distal ureter with subsequent ureteroureterostomy or extravesical ureteroneocystostomy is feasible and safe. Radical surgery to the urinary tract should be considered as a legitimate part of a gynecologic oncologist's surgical armamentarium to increase a patient's probability of survival and its positive effect on kidney function.

Endoscopic treatment of vesicoureteric reflux in transplanted kidneys

Twenty-one patients underwent endoscopic subureteric injection of Polytef paste for the correction of secondary vesicoureteric reflux (VUR) in transplanted kidneys. Ureteroneocystotomy was performed in renal transplants using an extravesical technique in 19 patients and the Leadbetter-Politano technique in 2 cases. Success was achieved in only 6 patients, including the 2 ureters reimplanted according to the Leadbetter-Politano technique. No significant complication relating to the technique was observed. Despite the low success rate (30%), endoscopic treatment of VUR in transplanted kidneys is justified as a first attempt in view of the morbidity of VUR and the difficulties of repeated surgical reimplantation in this population.

Non-antireflux versus antireflux ureteroneocystostomy in adults

A retrospective analysis of ureteric reimplantation in adults showed that a high proportion (71%) had been treated by non-antireflux procedures. Analysis of the ureteroneocystostomy success rate in aetiological groups where either antireflux or non-antireflux techniques were used indicated the superiority of antireflux surgery in the prevention of reflux. The risk of stenosis at the site of anastomosis was equal in both groups. No significant difference in the preservation of renal function was detected in the 2 groups. It was concluded that antireflux procedures offered no advantage over non-antireflux ureteric reimplantation in adults.

Pyelonephritis following pediatric renal transplant: increased incidence with vesicoureteral reflux

The association between pyelonephritis and vesicoureteral reflux (VUR) following pediatric renal transplantation is unclear. To understand the relationship of vesicoureteral reflux with urinary tract infection (UTI) and pyelonephritis, 67 patients were evaluated for reflux and pyelonephritis. Sixty-seven pediatric patients, aged 2 to 18 (39 males and 28 females) underwent renal transplantation. Beginning in 1982, all patients underwent voiding cystourethrography or radionuclide voiding studies 1 to 3 months postoperatively to assess the incidence of VUR. Techniques of ureteroneocystostomy (UNC) included the Leadbetter-Politano (L-p) in 39 cases, and two different modifications of the LICH (herein called LICH-1 and LICH-2) in 30 cases. Urinary cultures were performed routinely. Pyelonephritis was considered present in any patient with UTI and increased serum creatinine or fever greater than 38.5. VUR occurred in 36% of patients; highest in LICH-1 (79%), intermediate in L-P (22%), and lowest in LICH-2 (9%). VUR was not statistically significantly higher in females (43%) v males (31%). UTI occurred in 37% of patients. The difference in incidence between females (54%) and males (26%) was significant (P less than .05). The frequency of UTI in patients with VUR was 46% v 33% in patients without reflux (NS). However, pyelonephritis that occurred in 16% of cases overall was present in 82% of UTIs in patients with reflux v 14% of UTIs in patient without reflux (P less than .01). Pyelonephritis is significantly increased in pediatric renal transplant patients with UTI was have VUR. A nonrefluxing UNC is advocated in all patients. All renal transplant patients should have routine monitoring of urinary cultures and should be evaluated of VUR posttransplant.

Caliceal clubbing and adjacent parenchymal scarring (always reflux nephropathy?) as a cause of end-stage renal failure

Various clinical and laboratory aspects in 15 kidney transplanted patients with urographic evidence of caliceal clubbing and adjacent parenchymal scarring in their native kidneys are reported. These lesions were found in 16 per cent of our series of kidney transplantations; below 35 years of age it was the second most frequent disease. In 9 of these patients severe vesicoureteral reflux had been demonstrated. In the remaining 6 patients reflux nephropathy was only a tentative diagnosis based on a striking similarity in the radiographs and in several clinical findings. Nine patients had symptoms (mainly related to urinary tract infection) from 1 to 17 years before diagnosis/urography, in 5 as early as the first year of life. Recurrent urinary tract infection and renal impairment were the most frequent disorders leading to the diagnosis. Replacement therapy was initiated at an average age of 32.7 years. Following renal transplantation urinary tract infection was documented in 37 per cent of patients whether the patient had been bilaterally nephrectomized or not.

External ureteroneocystostomy in renal transplantation

The urologic complications of 184 consecutive renal transplants (68 living-related and 116 cadaveric) performed at Walter Reed Army Medical Center are reviewed. An anterior extravesical technique modified from Witzel, Sampson, and Lich was used to reimplant the ureter. Urologic complications occurred in 11 patients (6%): urine leak (4), obstruction (3), stricture (3), and total ureteral necrosis (1). These complications occurred in the first 115 patients; no complications have been documented in the last 69 patients. The several advantages of extravesical ureteroneocystostomy include: less operative time, avoidance of a separate cystotomy, virtually no hematuria, ability to use short ureters, no need for splints or stents, shortened Foley catheter drainage, and no interference with native ureteral function. Complications are few and become uncommon with practice.

The transplanted kidney. Diagnostic and interventional radiology

Following kidney allotransplantation a great number of complications threaten the patient and his graft, e.g. acute tubular necrosis, acute and chronic rejection, urologic and vascular complications and complications due to the immunosuppressive treatment. During the last decade a number of technical developments in radionuclide, ultrasonographic and radiographic imaging and intervention has significantly improved the possibility of early recognition and handling of such complications. Knowledge of the capability and limitations of the various techniques is of vital importance for their rational use. The aim of this review article is to give a short description of the various imaging modalities, the rational monitoring of the posttransplant patient, and possible handling of complications by the aid of imaging techniques.

Renal transplantation in children with obstructive uropathy

The outcome of renal transplantation was examined in 52 pediatric patients (mean age 13 years) whose primary renal disease was obstructive uropathy. The bladder was used at transplantation in 45 allograft recipients, 39 of whom had had a previous lower urinary tract operation or bladder defunctionalization. An ileal loop was used in 7 recipients. The 52 patients received 73 renal allografts from 58 cadaver and 15 live-related donors. Presently, 40 patients (77 per cent) have functioning allografts, 4 have returned to dialysis and 8 (15 per cent) have died. The results indicate that the outcome of renal transplantation in patients with obstructive uropathy is similar to that of other transplant recipients. Damaged and defunctionalized bladders may be used successfully in most cases. If necessary an ileal conduit is an effective alternative. Post-transplant urologic complications occur with increased frequency but with appropriate management allograft salvage and patient survival are excellent.