Primary Percutaneous Treatment of Transplant Ureteral Strictures Using Tandem Stents

Preliminary Outcomes of Different Tactics of Ureteral Stent Placement in Patients with Ureteral Stricture Undergoing Balloon Dilatation: Experience from a Large-Scale Center

Purpose

Our aim is to demonstrate the optimal number of ureteral stent placements in patients with a ureteral stricture (US) after balloon dilatation (BD).

Methods

A retrospective analysis of 213 patients who underwent BD from 2011 to 2019 was conducted. All statistical analyses were completed by software SPSS 25.0.

Results

Of the patients enrolled, 119 were males and 94 were females. The average age was 44.71 years. One month after stent removal, the overall success rate of ureteral stent placement was 76.99%, and the success rates of single, double, and triple stent groups were 81.7%, 70.3%, and 79.3%, respectively. Six months after stent removal, the overall success rate was 61.9%, and the success rates of the three groups were 61.7%, 52.7%, and 74.1%, respectively. Twelve months after stent removal, the overall success rate was 55.9%, and the success rates of the three groups were 51.9%, 48.6%, and 70.7%, respectively. During indwelling of the stents, the proportions of severe bladder irritation symptoms in the three groups were 13.6%, 16.2%, and 20.7%, respectively. Multivariate analysis indicated the length of US and the time and number of ureteral stent placements were independent risk factors of the treatment effect at 6 months and 12 months after stent removal. Patients in the triple stent group had a better prognosis when compared to those in the single or double stent group.

Conclusion

The long-term effect of three stents was better than that of single and double stents, but the success rate of treatment reduced gradually over time.

Simultaneous antegrade urography of the upper urinary tract and retrograde cystography combined with computed tomography imaging in the management of ureteral complications after renal transplantation

Background

To investigate the significance of simultaneous urography of the upper and lower urinary tract of transplanted kidneys combined with computed tomography urography (CTU), computed tomography arteriography (CTA), and computed tomography venography imaging in the planning of open surgery performed to treat any ureteral complications of a transplanted kidney.

Methods

In all, 24 patients with ureteral complications after renal transplantation were admitted, 12 of whom had renal graft ostomy during open surgery. Simultaneous antegrade urography of the upper urinary tract and retrograde cystography of the transplanted kidneys were performed on the patients. With the use of computed tomography imaging results, surgical planning was carried out.

Results

All surgeries were successfully completed according to preoperative planning. Three patients underwent end-to-end anastomosis of the ureter and bladder muscle flap, 8 patients underwent ureterocystostomy, and 1 patient underwent an end-to-end ureteral anastomosis. After the follow-up up to now, all the patients had stable renal function, and no complications such as ureteral stenosis or urine leakage have thus far reoccurred in the transplanted kidneys.

Conclusions

When open surgery is required to treat any ureteral complications following renal transplantation, preoperative multiangle imaging can be used to better understand the condition of the transplanted urinary tract and thus aid considerably in surgical planning.

Imaging of Renal Transplant Complications throughout the Life of the Allograft: Comprehensive Multimodality Review

The kidney is the most commonly transplanted solid organ. Advances in surgical techniques, immunosuppression regimens, surveillance imaging, and histopathologic diagnosis of rejection have allowed prolonged graft survival times. However, the demand for kidneys continues to outgrow the available supply, and there are efforts to increase use of donor kidneys with moderate- or high-risk profiles. This highlights the importance of evaluating the renal transplant patient in the context of both donor and recipient risk factors. Radiologists play an integral role within the multidisciplinary team in care of the transplant patient at every stage of the transplant process. In the immediate postoperative period, duplex US is the modality of choice for evaluating the renal allograft. It is useful for establishing a baseline examination for comparison at future surveillance imaging. In the setting of allograft dysfunction, advanced imaging techniques including MRI or contrast-enhanced US may be useful for providing a more specific diagnosis and excluding nonrejection causes of renal dysfunction. When a pathologic diagnosis is deemed necessary to guide therapy, US-guided biopsy is a relatively low-risk, safe procedure. The range of complications of renal transplantation can be organized temporally in relation to the time since surgery and/or according to disease categories, including immunologic (rejection), surgical or iatrogenic, vascular, urinary, infectious, and neoplastic complications. The unique heterotopic location of the renal allograft in the iliac fossa predisposes it to a specific set of complications. As imaging features of infection or malignancy may be nonspecific, awareness of the patient's risk profile and time since transplantation can be used to assign the probability of a certain diagnosis and thus guide more specific diagnostic workup. It is critical to understand variations in vascular anatomy, surgical technique, and independent donor and recipient risk factors to make an accurate diagnosis and initiate appropriate treatment.^©RSNA, 2019.

Comparison of tandem ureteral stents, cryoplasty, and cutting balloon ureteroplasty in treatment of refractory transplant ureteral strictures

The objective of study was to compare clinical outcome of cryoplasty, tandem stents, and cutting balloon ureteroplasty as "bailout procedures" to prevent surgical intervention or stent dependency in renal transplant patients with refractory ureteral stricture. All patients who underwent a bailout procedure from June 11, 2003, to August 8, 2015, at a single institution were reviewed retrospectively. Refractory ureteral stricture was defined as ureteral stenosis not responding to at least two prior percutaneous plain balloon ureteroplasties. Primary patency was defined as stable allograft function following the procedure with unobstructed urine outflow, not requiring indwelling ureteral stent, repeat ureteroplasty, or surgical revision. Sixty-one procedures were performed on 51 patients. Patients were followed up for a median of 286 days. Overall primary patency rate was 26.1%. Primary patency rate by method was 38.1%, 23.1%, and 14.3% after cryoplasty, tandem stent placement, and cutting balloon dilatation, respectively (P = .260). Primary patency rate was higher in early (<3 months post-transplant) ureteral strictures (35.7% vs 13.3%; P = .047). More complications identified in patients who had tandem ureteral stents (P = .00754). As some renal transplant patients may not be good operative candidates for ureteral revision, it would be reasonable to attempt one of these "bailout" interventions as long as the clinical team and patient are aware of overall low potential for achieving primary patency.

Impact of ureteral stricture and treatment choice on long-term graft survival in kidney transplantation

We aimed to evaluate the influence of urological complications occurring within the first year after kidney transplantation on long-term patient and graft outcomes, and sought to examine the impact of the management approach of ureteral strictures on long-term graft function. We collected data on urological complications occurring within the first year posttransplant. Graft survivals, patient survival, and rejection rates were compared between recipients with and without urological complications. Male gender of the recipient, delayed graft function, and donor age were found to be significant risk factors for urological complications after kidney transplantation (P < .05). Death censored graft survival analysis showed that only ureteral strictures had a negative impact on long-term graft survival (P = .0009) compared to other complications. Death censored graft survival was significantly shorter in kidney recipients managed initially with minimally invasive approach when compared to the recipients with no stricture (P = .001). However, graft survival was not statistically different in patients managed initially with open surgery (P = .47). Ureteral strictures following kidney transplantation appear to be strongly negatively correlated with long-term graft survival. Our analysis suggests that kidney recipients with ureteral stricture should be managed initially with open surgery, with better long-term graft survival.

The accordion sign in the transplant ureter: ramifications during balloon dilation of strictures

PURPOSE

This study was designed to demonstrate the accordion sign within the transplant ureter and evaluate its ramifications during balloon dilation of strictures.

METHODS

A retrospective electronic chart and imaging review included demographic characteristics, procedure reports, and complications of 28 renal transplant patients having ureteral strictures treated with percutaneous balloon dilation reported in our transplant nephrology database during an 8-year period. The accordion sign was deemed present or absent on the basis of an imaging review and was defined as present when a tortuous ureter became kinked and irregular when foreshortened after placement of a wire or a catheter. Procedure-related urine leaks were categorized as occurring at the stricture if within 2 cm; otherwise, they were considered away from the stricture.

RESULTS

The accordion sign was associated with a significantly greater occurrence of leaks away from the stricture (P = 0.001) but not at the stricture (P = 0.34).

CONCLUSIONS

The accordion sign is an important consideration when performing balloon dilation procedures on transplant ureteral strictures, given the increased risk of leak away from the stricture. Its presence should prompt additional care during wire and catheter manipulations.