Incidence of Ureteral Strictures After Laparoscopic Donor Nephrectomy

Observations on hydronephrosis after pig kidney transplantation in baboons

We have seen hydronephrosis (obstructive nephropathy) at necropsy in 3 of 11 (21%) genetically-engineered pig kidneys that functioned in baboons for >36 days, even when the clinical and histopathological features of rejection were minimal. We briefly report one such case and illustrate the macroscopic and microscopic appearances of such a kidney and ureter. The causes of the observed changes remain uncertain. In our small experience, there seems to be no correlation between the development of hydronephrosis and (i) the surgical technique, (ii) the genotype of the pig, (iii) the length of the pig ureter, or (iv) the immunosuppressive and anti-inflammatory therapy administered. We suggest that the distal ureteric thickening may be the result of an inflammatory response. In two cases, we resolved the problem by carrying out a secondary side-to-side anastomosis between the proximal pig ureter and the baboon bladder.

In vivo urinary compatibility of Mg-Sr-Ag alloy in swine model

A biodegradable metallic ureteral stent with suitable mechanical properties and antibacterial activity remains a challenge. Here we reveal the scientific significance of a biodegradable Mg-Sr-Ag alloy with a favorable combination of balanced mechanical properties, adjustable indwelling time in urinary tract and evident antibacterial activity via in vivo experiments in a swine model. Attributed to the rheo-solidification process, equiaxial microstructure and significantly refined grains (average grain size: 27.1 μm) were achieved. Mg₁₇Sr₂ and Mg₄Ag were found as the primary precipitates in the matrix, due to which the alloy obtained ca. 111% increase in ultimate tensile strength in comparison to pure magnesium. Both the in vitro and in vivo results demonstrated the satisfactory biocompatibility of the alloy. Histological evaluation and bioindicators analysis suggested that there was no tissue damage, inflammation and lesions in the urinary system caused by the degradation process. The stent also improved the post-operative bladder functions viewed from the urodynamic results. Our findings highlight the potential of this alloy as antibacterial biodegradable urinary implant material.

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Innovative biodegradable antibacterial Mg-Sr-Ag alloy.

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In vivo study in pig ureter models.

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Enhanced mechanical properties and adjustable indwelling time.

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Outstanding urinary compatibility and evident antibacterial activity.

Management of a ureteric stricture post ureteroileal anastomosis of a renal transplant

A 58-year-old woman with a prior radical cystectomy and ileal conduit underwent a living-related donor renal transplant for end-stage renal disease secondary to autoimmune glomerulonephritis. She subsequently developed an ischaemic stricture of the transplant ureter. A successful ureteropyelostomy was performed with the native right ureter anastomosed to the pelvis of the renal transplant. She presented to the emergency department 18 months later feeling unwell and with raised inflammatory markers. Imaging demonstrated a large soft tissue mass over the right psoas muscle and hydronephrosis of the native right kidney. A nephrostomy and nephrostogram of the native right kidney diagnosed a urine leak from the native right kidney and she underwent an open right native nephrectomy. She recovered well postoperatively and continues to have excellent graft function. Renal transplantation in an abnormal urinary tract carries a high risk of complications. A multidisciplinary team approach is essential in offering the most appropriate treatment and ensuring good graft function is preserved.

In vivo assessment of biodegradable magnesium alloy ureteral stents in a pig model

Today, ureteral stent technology is making progress towards the reduction of complications and patient discomfort. Therefore, magnesium alloys have become excellent candidate materials for manufacturing ureteral stents due to their biodegradability and antibacterial activity. Built on our previous work on biodegradable magnesium alloys, this article reports a semisolid rheo-formed magnesium implant that displays degradability and biocompatibility in vivo, and feasibility as ureteral stents in a pig model. Refined non-dendritic microstructure was observed in the rheo-formed alloy, whose grain size and shape factor were ca. 25.2 μm and ca. 1.56 respectively. Neither post-interventional inflammation nor pathological changes were observed in the urinary system during the implantation period of 14 weeks, and the degradation profile (14 weeks) meets the common requirement for the indwelling time of ureteral stents (8 to 16 weeks). Furthermore, histopathological observation and urinalysis results confirmed that the alloy had significantly higher antibacterial activity than the medical-grade stainless steel control. To our knowledge, this is the first in vivo study of biodegradable magnesium alloy as urinary implants in large animal models. Our results demonstrate that magnesium alloys may be a reasonable option for manufacturing biodegradable ureteral stents.

European experience of robot-assisted kidney transplantation: minimum of 1-year follow-up

OBJECTIVES

To evaluate functional results, graft survival and late complications in patients who underwent robot-assisted kidney transplantation (RAKT) and who had a minimum of 1 year of follow-up data, and to analyse the correlations between surgical data and functional results at a minimum of 1-year postoperatively and between renal function in the immediate postoperative period and after 1 year.

MATERIALS AND METHODS

A common prospectively collected RAKT database was created by the European Robotic Urological Section (ERUS) RAKT working group, which included eight different European centres. In each centre RAKTs were performed with kidneys from living donors. Data on demographic variables, surgical results, graft survival, functional outcomes (creatinine and estimated glomerular filtration rate [eGFR]) on postoperative days 7 and 30 and at 1 year, and late complications were extracted from the common database.

RESULTS

A total of 147 RAKTs were performed by the ERUS RAKT working group. Of the 147 patients, 83 had at least 1-year follow-up (mean [range] 21 [13-27] months). Of these 83 patients, 30 were women. The patients' median (range) age was 43 (30-75) years, body mass index was 25.3 (20-40) kg/m² , pre-transplantation serum creatinine was 517 (198-1 414) μmol/L and estimated GFR (eGFR) was 10 (3-29) mL/min per 1.73 m² . Of the 83 cases, 46 were pre-emptive. The median (range) overall ischaemia time was 116 (53-377) min. The median (range) rewarming time was 60 (35-110) min. At 1-year follow-up, the median (range) serum creatinine was 131 (66-244) μmol/L, with a median (range) eGFR of 57.4 (28-97) mL/min per 1.73 m² . There was no statistically significant difference between functional data at postoperative day 30 and those at 1 year for creatinine (P = 0.78) or eGFR (P = 0.91). Regarding the correlation between the surgical data and the functional outcomes, the data showed that overall operating time and rewarming time did not affect the graft function at 1 year. Three cases of graft loss occurred as a result of massive arterial thrombosis within the first postoperative week. Late complications comprised one case of ureteric stenosis and one case of graft pyelonephritis. No late vascular complications or cases of incisional hernia were recorded.

CONCLUSION

Findings at 1-year follow-up indicate RAKT from a living donor to be a safe procedure in a properly selected group of recipients. RAKT was associated with a low complication rate and there was maintenance of excellent graft survival and function. This is the first and largest study to report functional results after RAKT from a living donor with a minimum follow-up of 1 year.

The Utility of Routine Ultrasound Imaging after Elective Transplant Ureteric Stent Removal

Background. Ureteric stent insertion during kidney transplantation reduces the incidence of major urological complications (MUCs). We evaluated whether routine poststent removal graft ultrasonography (PSRGU) was useful in detecting MUCs before they became clinically or biochemically apparent. Methods. A retrospective analysis was undertaken of clinical outcomes following elective stent removals from adult single renal transplant recipients (sRTRs) at our centre between 1 January 2011 and 31 December 2013. Results. Elective stent removal was performed for 338 sRTRs. Of these patients, 222 had routine PSRGU (median (IQR) days after stent removal = 18 (11–31)), 79 had urgent PSRGU due to clinical or biochemical indications, 12 had CT imaging, and 25 had no further renal imaging. Of the 222 sRTRs who underwent routine PSRGU, 210 (94.6%) had no change of management, three (1.4%) required repeat imaging only, and eight patients (3.6%) had incidental (nonureteric) findings. One patient (0.5%) had nephrostomy insertion as a result of routine PSRGU findings, but no ureteric stenosis was identified. Of 79 patients having urgent PSRGU after elective stent removal, three patients required transplant ureteric reimplantation. Conclusions. This analysis found no evidence that routine PSRGU at two to three weeks after elective stent removal provides any added value beyond standard clinical and biochemical monitoring.

Laparoscopic ureterolysis with simultaneous ureteroscopy and percutaneous nephroscopy for treating complex ureteral obstruction after failed endoscopic intervention: A technical report

Objective

Complex ureteral obstruction is refractory to conventional urological intervention. This report describes a case of laparoscopic ureterolysis with simultaneous ureteroscopy and percutaneous nephroscopy for treating complex ureteral obstruction.

Methods

Right-side multiple ureteral stones and complicating ureteral obstruction failed an initial attempt of ureteroscopy lithotripsy with simultaneous percutaneous nephroscopy in a 23-year-old male. Laparoscopic ureterolysis with ureteroscopy and percutaneous nephroscopy was used simultaneously to dissect the periureteral adhesions with the patient placed in the Galdakao-modified supine Valdivia position. The ureter was incised to allow the insertion of a ureteral catheter through the twisted ureter, and a guide wire was advanced into the pelvis using ureteroscopy. A double-J stent was placed into the right-side ureter using antegrade percutaneous nephroscopy.

Results

The laparoendoscopic procedure lasted 330 min with an estimated bleeding volume of 100 mL. The patient underwent an uneventful postoperative course, and postoperative follow-up radiography confirmed good positioning of the double-J stent. The double-J stent was removed 3 months after operation. The patient remained asymptomatic within a 13-month follow-up period.

Conclusion

Laparoscopic ureterolysis with simultaneous ureteroscopy and percutaneous nephroscopy is an effective and safe treatment option for complex ureteral obstruction.

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.

Native ureteropyelostomy in the treatment of obstructive uropathy in adult renal transplant. Experience and technical alternatives

OBJECTIVE

To analyze and evaluate our experience in surgical treatment with the open approach of the complex ureteral stenosis after adult kidney transplantation in a tertiary level hospital in the last seven years. We have reviewed the different surgical options used.

PATIENTS AND METHODS

A total of 589 consecutive adult renal transplants were performed from January 2005 to December 2012. Of these, 1.1% showed some degree of symptomatic obstructive uropathy which after initial urinary diversion required open surgical approach using the ipsilateral or contralateral native urinary tract. Characteristics of the patient, clinical examinations performed and surgical technique performed as well as their results are presented.

RESULTS

During the period under review, in 5 men and 2 women who had ureteral stenoses after renal transplant, 7 reparative surgeries were performed by open ureteropyelostomy, using ipsilateral native ureter in 6 cases and contralateral ureter in the remaining case. In one case, uretero-calicial anastomosis was performed due to severe pyelic shrinkage. There were no significant complications. Native kidney nephrectomy was not required for further complications. All the patients operated on had optimum plasma creatinine levels with resolution of previous dilatation.

CONCLUSIONS

The initial percutaneous nephrostomy followed by open surgical repair using native ureter represents a definitive, valid and optimal alternative in terms of safety and preservation of renal function.

Mini-laparoscopic live donor nephrectomy with the use of 3-mm instruments and laparoscope

PURPOSE

To analyze our preliminary outcomes on the use of 3 mm instruments for laparoscopic live donor nephrectomy (LLDN).

METHODS

Our series includes thirteen patients, who underwent LLDN using 3-mm instruments and laparoscope and 5-mm transumbilical trocar. The patients were followed at 7 and 14 days from discharge and were specifically asked about their cosmetic satisfaction. At follow-up, the recipient graft function was controlled, as well as the donor's cosmetic results. Eight months after surgery, all thirteen patients were asked to fill out the Patient Scar Assessment Questionnaire and Scoring System (PSAQ).

RESULTS

All patients presented good recovery after surgery. Regarding cosmetic outcomes, the donors expressed their satisfaction toward the minimal incision size and optimal esthetic results at 7 and 14 days from discharge home. The low scores on each section of the PSAQ confirmed the favorable outcomes. Early graft function was satisfactory at 1 and 3 months after the kidney transplantation. Furthermore, there were no major complications in the recipients.

CONCLUSIONS

Our persistent positive results with the use of 3-mm instruments during LLDN support this technique as a good alternative to the standard laparoscopic approach for minimizing the incision site, while maintaining safety and excellent clinical outcomes. The fact that the general laparoscopic standards are maintained could make this approach a very attractive alternative to the other minimally invasive approaches for live donor nephrectomy. The hope is in that the higher degree of satisfaction in the donor population demonstrated in this study may likely enhance living kidney donation.

Ureteropyelostomy using the native ureter for the management of ureteric obstruction or symptomatic reflux following renal transplantation

OBJECTIVE

To evaluate the outcome of ureteropyelostomy using the native ureter for the management of ureteric obstruction or symptomatic reflux after renal transplantation.

MATERIALS AND METHODS

This is a single-center retrospective review of consecutive patients who underwent ureteropyelostomy after renal transplantation between the years 2000 and 2009. Ureteropyelostomy was performed using the ipsilateral native ureter. The native kidney was not removed. Patients' baseline characteristics, preceding interventions, and postprocedural outcomes were analyzed.

RESULTS

Ten patients underwent ureteropyelostomy after renal transplantation. All had initial Lich Gregoir ureterovesical anastomosis. Reasons for the reconstructive surgery were transplant ureteric stenosis in 8 patients or vesicoureteric reflux causing recurrent graft pyelonephritis in 2 patients. Median follow-up was 53 months (range 24-76). Postoperative complications included 3 patients who had transient anastomotic obstruction after removal of the double pigtail stent. They were managed with short-term ureteric restenting or nephrostomy tube insertion. In addition, 2 patients required delayed ipsilateral native nephrectomy because of infection. At last follow-up, all grafts remained unobstructed and free of infections.

CONCLUSION

Ureteropyelostomy using the native ureter for the management of transplant ureteric obstruction or symptomatic reflux is safe and provides good long-term preservation of graft function in selected patients.

Laparoscopic live donor nephrectomy with the use of 3-mm instruments and laparoscope: initial experience at a tertiary center

Laparoscopy has become the standard of care for kidney recovery during live donor nephrectomy (LDN) because of the well-documented better outcomes of minimally invasive surgery compared with the open approach. Especially in the donor population, the cosmetic results are of great importance; therefore, an effort to reduce the incision size should be attempted while maintaining the safe general principles of surgery. We present our initial experience with the use of 3-mm instruments for laparoscopic LDN.

Ureteral complications in the era of laparoscopic living donor nephrectomy: do we need to preserve the gonadal vein with the specimen?

BACKGROUND AND PURPOSE

The aim of this study was to analyze the ureteral complication rate in recipients transplanted with laparoscopically retrieved kidneys in our institution's 8-year experience when the gonal vein was not preserved with the specimen during the donor procedure.

PATIENTS AND METHODS

We reviewed the records of 800 consecutive laparoscopic donor nephrectomy patients. Donor sex, age, body mass index, warm ischemia time, hospital length of stay, donor and recipient serum creatinine levels, and incidence and type of complications including the incidence of ureteral complications were recorded.

RESULTS

Mean patient age was 39 +/- 10 years. Mean body mass index was 27 +/- 5. A total of 482 cases were treated purely laparoscopically. Of them, 318 were performed hand assisted. Seven hundred and ninety-three procedures were done on the left side and seven were done on the right side. The overall rate of intraoperative complications was 2.9%. The overall open conversion rate was 1.4%. The overall rate of postoperative complications was 3.9%. The postoperative day-7 serum creatinine values of the donors were 1.4 +/- 0.3 mg/dL. Mean creatinine in all patients at 1 week after transplantation was 1.5 +/- 0.2 mg/dL. We had one case of ureteral stricture in the recipients of laparoscopically procured kidneys without gonadal vein preservation technique among 800 patients.

CONCLUSION

Gonadal vein preservation with the entire specimen during laparoscopic donor nephrectomy procedure is not a necessary step to protect periureteral blood supply to prevent ureteral strictures.

Experience with 750 consecutive laparoscopic donor nephrectomies--is it time to use a standardized classification of complications?

PURPOSE

Laparoscopic living donor nephrectomy offers patients the benefits of decreased morbidity and improved cosmesis, while maintaining equivalent graft outcomes and complication rates similar to those of open donor surgery. With expressed concern for donor safety, using a standardized complication scale would allow combining data in a donor registry so potential donors could be adequately followed and counseled. We present the largest series to our knowledge of laparoscopic living donor nephrectomy by a single surgeon.

MATERIALS AND METHODS

The institution's initial 750 laparoscopic living donor nephrectomies were included in the study, and a retrospective and prospective chart and database analysis was performed.

RESULTS

Mean donor age was 40.5 years and average body mass index was 25.7 kg/m(2). There were 175 patients (23%) with 2 or more renal arteries while 161 (21.5%) had early arterial bifurcations. There were 3 open conversions (0.4%) and the overall complication rate was 5.46%. Median hospital stay was 1 day and the readmission rate was 1.2%. There were 5 reoperations (0.67%), none of which was for the control of bleeding. No patients required a blood transfusion and there were no mortalities. Using a modified Clavien classification of complications for living donor nephrectomy 65.8% were grade 1, 31.7% grade 2 (12.2% grade 2a, 14.6% grade 2b, 4.9% grade 2c) and 2.4% grade 3. There were no grade 4 complications.

CONCLUSIONS

With appropriate patient selection and operative experience, laparoscopic living donor nephrectomy is a safe procedure associated with low morbidity. The use of a standardized complication system specific for this procedure is encouraged and could aid in counseling potential donors in the future.