Complications urologiques de la transplantation rénale

[Surgical outcomes and complications following third kidney transplantation]

BACKGROUND

After two consecutive kidney transplant failures, a third kidney transplantation improves survival for patients on the waiting list. The surgical outcomes and complications of third kidney transplantations remain poorly known.

METHODS

We analyzed the last 100 third kidney transplantations performed in our center between January 2000 and August 2018. The data, relating to donors and recipients, were extracted retrospectively from medical records and from the prospective DIVAT database (computerized and validated data in transplantation). Continuous variables are expressed as means, medians, first and third quartiles (median, [Q1;Q3]). Categorical variables are expressed as percentages. Patient and transplant survivals were calculated using the Kaplan-Meier method.

RESULTS

Mean age of recipients was 46.4 years (47, [36;53]). Thirty-five percent had kidney failure due to urinary tract malformations. Mean age of donors was 48.2 years (52, [39.75; 58]) with 63% of donors with standard criteria. Mean cold ischemia time was 22.4hours (21, [16.5; 29.2]). Surgical mortality rate was 2% and surgical complication rate was 45%. Third kidney transplants survival was 73.1% and 58.8% at 5 years and 10 years. Mortality rate with a functioning transplant was 18%.

CONCLUSION

A third kidney transplant offers satisfactory functional outcomes but remains associated with high morbi-mortality and a significant death rate with a functioning transplant.

LEVEL OF EVIDENCE: 4

[Indocyanine green fluorescence to visualize the ureteric vascularization of kidney transplants: An exploratory study]

INTRODUCTION

Urinary complications after kidney transplantation are common and can compromise renal function. While they are mainly attributed to ischemic lesions of the ureter, there is no existing method to evaluate its vascularization during surgery. The aim of the study was to evaluate if indocyanine green, revealed by infra-red light andused to visualize tissue perfusion, could provide an appreciation of the ureter's vascularization during kidney transplantation.

METHODS

This feasibility study was conducted over one month, on eleven consecutive kidney transplants. During transplantation, an injection of indocyanine green enabled the surgeon to visualize in real time with an infra-red camera the ureter fluorescence. Its intensity was reported on a qualitative and semi-quantitative scale. Occurrence of urinary complications such as stenosis or ureteral fistula were collected during 6 months.

RESULTS

In all of the 11 cases (100%), the last centimeters of the ureters were not fluorescent. Three (27%) ureters were poorly or partiallly fluorescent. Out of these three cases, only one case of urinary fistula occurred, followed by ureteric stenosis. In the series, two fistulas (18%) and two ureteric stenoses (18%) occurred. No side effects were observed. The low number of events did not allow statistical analysis.

CONCLUSION

Infra-red fluorescence of indocyanine green could be a simple and innovative way to appreciate the transplant's ureteric vascularization during kidney transplantation. It could help surgeons to identify the level of ureter section and to decide the anastomosis technique, in order to limit urinary complications.

LEVEL OF EVIDENCE

3.

[Results of surgical revisions for ureteral complications after renal transplantation]

OBJECTIVE

To analyze the results of surgical revision for ureteral complication (ureteric stenosis or urinary leakage) after renal transplantation over a period of 10 years.

MATERIALS AND METHODS

We performed a retrospective study on 1313 consecutive kidney transplantations carried out in a University Hospital Center between 2005 and 2014. The data of the patients who developed a ureteral stenosis or a urinary leakage secondary to a renal transplantation were analyzed. Combined organ transplantations (kidney-liver and kidney-pancreas), as well as pediatric transplantations were excluded.

RESULTS

Seventy-six patients (5.8%) had ureteric stenosis or urinary leakage after renal transplantation. Forty-six patients (3.5%) underwent surgical revision: 27 for ureteral stenosis, 19 for urinary leakage. Early success was achieved in 26 patients (56.5%), including 14 ureteric stenosis (51.9%) and 12 urinary leakage (63.2%) (P=0.45). After a complementary endoscopic or surgical treatment, the final success rate was increased to 73.1% (34 patients): 20 ureteric stenosis (74.1%) and 14 urinary leakage (73.7%) (P=0.98). There were 2 graft losses (4.3%) and one death (2.2%). The mean glomerular filtration rate estimated by the MDRD was 44.58mL/min/1.73m² (±14.7) before surgery and 45.37mL/min/1.73m² (±16.5) 6 months after surgery (P=0.92).

CONCLUSION

Although frequently challenging, surgical revisions for ureteral complications after renal transplantation give good results, with a low rate of graft loss and mortality.

LEVEL OF EVIDENCE

4.

Ureteral Stenosis After Renal Transplantation-A Single-Center 10-Year Experience

BACKGROUND

Kidney transplantation (KT) is the definitive treatment for ESRD. Ureteral stenosis (US) is one of the most common urologic complications and has been reported in 2.6%-15% of KTs.

METHODS

We reviewed data for 973 consecutive KT procedures performed at our center from January 2004 to September 2014, with evaluation of US management and recurrence rate.

RESULTS

The 973 KTs were performed with the use of the direct ureterovesical (UV) implantation Paquin technique, and the mean follow-up time was 44.3 ± 30.2 [range, 3-111] months. During this period, 33 cases of US (3.39%) were reported. The interval from KT to US diagnosis was 10.6 ± 23.0 (range, 0.5-98.0) months. The majority of the US cases were located in the distal ureter and UV junction (83.9%), with only 2 cases of middle ureter stenosis and 2 cases of ureteropelvic junction. Mean US length was 2.5 ± 1.9 (range, 1.0-10.0) cm. Surgical management and global and treatment-specific recurrence rates were reviewed. Primary surgical treatment recurrence rate was higher for the endoscopic approach, with a mean global time from treatment to US recurrence of 6.9 ± 16.3 (range, 0-65) months and a median of 2.0 months. Open surgical approach was the main recurrence treatment option (74%). There were 2 cases of graft loss. Success rate evaluation of overall and treatment-specific primary surgical management did not reveal significant differences (P > .05) according to stenosis length (<1.5, 1.5-3.0, or >3.0 cm), time between transplant and stenosis (≤3, 3-12, or >12 mo), or stenosis location (distal, middle, or upper ureter). However, there was clearly a trend to higher success rate in smaller stenosis (<1.5 cm) and early management (≤3 mo), particularly with the use of balloon dilation.

CONCLUSIONS

US management should be decided on a case-by-case basis according to clinical characteristics, treatment-specific recurrence rate, and previous surgical options.

First Case Report of Acute Renal Failure After Mesh-Plug Inguinal Hernia Repair in a Kidney Transplant Recipient

Acute renal failure due to ureter compression after a mesh-plug inguinal repair in a kidney transplant recipient has not been previously reported to our knowledge. A 62-year-old man, who successfully underwent kidney transplantation from a deceased donor 6 years earlier, was admitted for elective repair of a direct inguinal hernia. The patient underwent an open mesh-plug repair of the inguinal hernia with placement of a plug in the preperitoneal space. We did not observe the transplanted ureter and bladder during dissection of the inguinal canal. Immediately after surgery, the patient became anuric, and a graft sonography demonstrated massive hydronephrosis. The serum creatinine level increased rapidly, and the patient underwent an emergency reoperation 8 hours later. During surgery, we did not identify the ureter but, immediately after plug removal, urine output increased progressively. We completed the hernia repair using the standard technique, without plug interposition, and the postoperative course was uneventful with complete resolution of graft dysfunction 3 days later. Furthermore, we reviewed the clinical features of complications related to inguinal hernia surgery. An increased risk of urological complications was reported recently in patients with a previous prosthetic hernia repair undergoing kidney transplantation, mainly due to the mesh adhesion to surrounding structures, making the extraperitoneal dissection during the transplant surgery very challenging. Moreover, older male kidney transplant recipients undergoing an inguinal hernia repair may be at higher risk of graft dysfunction due to inguinal herniation of a transplanted ureter. Mesh-plug inguinal hernia repair is a safe surgical technique, but this unique case suggests that kidney transplant recipients with inguinal hernia may be at higher risk of serious urological complications. Surgeons must be aware of the graft and ureter position before proceeding with hernia repair. A prompt diagnosis with graft sonography and abdominal computed tomography scan and emergency surgery may avoid the need for nephrostomy and may resolve graft dysfunction more rapidly.