Ureteral Complications in Kidney Transplantation: Analysis and Management of 853 Consecutive Laparoscopic Living-Donor Nephrectomies in a Single Center

Impact of early surgical complications on kidney transplant outcomes

BACKGROUND

Kidney transplantation (KT) improves clinical outcomes of patients with end stage renal disease. Little has been reported on the impact of early post-operative surgical complications (SC) on long-term clinical outcomes following KT. We sought to determine the impact of vascular complications, urological complications, surgical site complications, and peri-graft collections within 30 days of transplantation on patient survival, graft function, and hospital readmissions.

METHODS

We conducted a single-centre, observational cohort study examining adult patients (≥ 18 years) who received a kidney transplant from living and deceased donors between January 1st, 2005 and December 31st, 2015 with follow-up until December 31st, 2016 (n = 1,334). Univariable and multivariable analyses were performed with Cox proportional hazards models to analyze the outcomes of SC in the early post-operative period after KT.

RESULTS

The cumulative probability of SC within 30 days of transplant was 25%, the most common SC being peri-graft collections (66.8%). Multivariable analyses showed significant relationships between Clavien Grade 1 SC and death with graft function (HR 1.78 [95% CI: 1.11, 2.86]), and between Clavien Grades 3 to 4 and hospital readmissions (HR 1.95 [95% CI: 1.37, 2.77]).

CONCLUSIONS

Early SC following KT are common and have a significant influence on long-term patient outcomes.

Ureterovesical Leak Following Renal Transplant and Effects of Acute Rejection and Antirejection Therapy: A Nested Case-Control Analysis and Outcome of 1102 Consecutive Renal Transplant Recipients

OBJECTIVES

Studies on nontechnical risk factors for ureterovesical leak after renal transplant are scarce. This study aimed to report the possible pre- and postoperative risk factors and the role of acute rejection and antirejection therapies for urine leak after transplant and its effect on graft and patient survival.

MATERIALS AND METHODS

We conducted a retrospective analysis of 13 patients (1.17%) with urine leak (case group) and 52 patients without leak (control group) (case-to-control ratio of 1:4) from 1102 living related (first degree) renal transplant recipients seen between January 2012 and December 2021. We analyzed demographic and clinical details and biochemical and outcome parameters using a nested case-control design.

RESULTS

Cases were olderthan controls (P = .018), were more ABO incompatible (P = .009), and had more 6/6 HLA mismatch transplants (P = .047). Donors of cases were older than donors of controls (P = .049). The rate of postoperative hypoalbuminemia was greaterin the case group (P = .050). Rates of acute rejection (P = .012) and plasmapheresis (P = .003) were greaterin the case group than in the control group. On multivariate logistic regression analysis, recipient age, 6/6 HLA mismatch, and plasmapheresis were found to independently associated with urine leak. None ofthe patient required surgical repair, as all responded to conservative therapy. Urine leak did not affect graft outcomes (P = .324), but overall survival was less in cases than in controls.

CONCLUSIONS

Nontechnical risk factors that cause posttransplant ureteric leak include older donor and recipient age and ABO incompatible and 6/6 HLA mismatch transplants. Acute rejection and plasmapheresis predispose leak, and an indwelling double J stent can allow adequate healing of the anastomosis. High index of suspicion and prompt management are imperative to preserve graft and patient outcome.

Positive Effect of Platelet-Rich Plasma on Neoureterocystostomy in Rats: An Experimental Study

OBJECTIVES

Some of the most common problems after kidney transplant are urologic complications, including ureterocystoanastomosis leakage and stenosis with the development of severe renal graft complications. Isolated plasma contains active substances that cause the activation of various growth factors for the processes of tissue repair or regeneration, has an anti- inflammatory effect, activates angiogenesis, and reduces the risk of infectious complications. Platelet-rich plasma is actively used to stimulate bone regeneration, heal wounds and ulcers on the skin, enhance reconstruction of the larynx and trachea, and ameliorate urethral damage, among other uses. This study was developed to evaluate the positive effect of platelet-rich plasma on the healing process of an anastomotic wound in a model of ureterocystoanas-tomosis in rats.

MATERIAL AND METHODS

We randomized 14 Wistar albino male rats into 2 groups: group 1 included 7 rats that received platelet-rich plasma after ureterocystostomy; group 2 was the control group and included 7 rats that underwent ureterocystostomy without platelet-rich plasma. On postoperative day 7, all animals were euthanized, and the anastomosis area was resected for determination of the tissue hydroxyproline levels and histopathology examination.

RESULTS

Tissue hydroxyproline levels were 767 ± 62.9 μg/g in group 1 and 256 ± 28.0 μg/g in group 2. Tissue hydroxyproline levels were significantly higher in group 1 compared with group 2 (P < .05). There were no significant differences in epithelial damage, acute inflammation, or fibrosis between the tissue samples of both groups.

CONCLUSIONS

The results of this study show that the use of platelet-rich plasma during ureterocystostomy produces a positive effect. Our further research will be devoted to the use of autologous platelet-rich plasma in ureterocystostomy in big models.

Ureterovesical Anastomosis Complications in Kidney Transplantation: Definition, Risk Factor Analysis, and Prediction by Quantitative Fluorescence Angiography with Indocyanine Green

Ureteral stenosis and urinary leakage are relevant problems after kidney transplantation. A standardized definition of ureterovesical anastomosis complications after kidney transplantation has not yet been established. This study was designed to demonstrate the predictive power of quantitative indocyanine green (ICG) fluorescence angiography. This bicentric historic cohort study, conducted between November 2015 and December 2019, included 196 kidney transplantations. The associations between quantitative perfusion parameters of near-infrared fluorescence angiography with ICG and the occurrence of different grades of ureterovesical anastomosis complications in the context of donor, recipient, periprocedural, and postoperative characteristics were evaluated. Post-transplant ureterovesical anastomosis complications occurred in 18%. Complications were defined and graded into three categories. They were associated with the time on dialysis (p = 0.0025), the type of donation (p = 0.0404), and the number of postoperative dialysis sessions (p = 0.0173). Median ICG ingress at the proximal ureteral third was 14.00 (5.00–33.00) AU in patients with and 23.50 (4.00–117.00) AU in patients without complications (p = 0.0001, cutoff: 16 AU, sensitivity 70%, specificity 70%, AUC = 0.725, p = 0.0011). The proposed definition and grading of post-transplant ureterovesical anastomosis complications is intended to enable valid comparisons between studies. ICG Fluorescence angiography allows intraoperative quantitative assessment of ureteral microperfusion during kidney transplantation and is able to predict the incidence of ureterovesical anastomosis complications. Registration number: NCT-02775838.

Risk Factors for Urologic Complications After Kidney Transplantation and Impact in Graft Survival

Background and Purpose

Kidney transplantation (KT) is the best therapy for chronic kidney disease (CKD). Major urologic complications (MUCs) are the second etiology associated to morbidity and graft loss following KT, after rejection episodes. The objective of this study was to estimate the incidence, risk factors and impact on graft survival associated to urological complications in KT patients.

Patients and Methods

A retrospective cohort based on electronic patient files of kidney transplant recipients from Colombiana de Trasplantes was created for the period August 2008 to September 2019. Initiation of follow-up was defined as the date of transplantation up to 3 years post-transplantation. Incidence of ureteral stenosis, ureteral obstruction, and ureteral leak was measured. A logistic regression multivariate model was adjusted to determine the associated factors to MUCs (yes/no). Patient and graft survival time were analyzed using a Kaplan-Meier method.

Results

A total of 1584 KT patients were included in the cohort. MUCs were present in 195 (12.6%) KT patients. We found that dialysis duration (OR: 1.004; p = 0.02) remained significant for the incidence of MUCs in KT patients of deceased donors. Probability of graft and patient survival at 3 years of follow-up was 90.5% and 85.5%, respectively. No significant difference was found on graft and patient survival in KT patients with or without MUCs.

Conclusion

MUCs are frequent complications for KT. We did not observe significant differences in graft or patient survival according to the presence of MUCs. The identification of MUCs and risk factors may guide transplant teams for future surgical and clinical decisions.

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.

Robot-assisted Transplant Ureteral Repair to Treat Transplant Ureteral Strictures in Patients after Robot-assisted Kidney Transplant: A Case Series

OBJECTIVE

To describe the use of robotic-assisted transplant ureteral repair (RATUR) for treating transplant ureteral stricture (TUS) in 3 patients who had undergone robot assisted kidney transplant (RAKT).

METHOD

We reviewed the medical records of 3 patients who experienced TUS after RAKT and who underwent RATUR between 2017 and 2020. The patients' RAKT, post-transplant clinical course, endourological interventions, reoperation, and recovery were assessed.

RESULTS

All patients diagnosed with TUS presented with deterioration of kidney function after RAKT. Method of diagnosis included ultrasound, antegrade ureterogram, and CT scan. All 3 patients had a short (<1 cm) area of TUS and underwent RATUR. For 2 patients, distal strictures were bypassed with modified Lich-Gregoir ureteroneocystostomy reimplantation. One patient was treated with pyelo-ureterostomy to the contralateral native ureter. No intraoperative complications, conversions to open surgery, or significant operative blood loss requiring blood transfusion for any patient were observed. Also, no patients had urine leaks in the immediate or late postoperative period. After RATUR, 2 patients developed Clavien grade II complications with rectus hematoma or urinary tract infection.

CONCLUSION

RATUR is a technically feasible operation for kidney transplant patients with TUS after RAKT. This procedure may provide the same benefits of open operation without promoting certain comorbidities that may occur from open surgical procedures.

Hand-Assisted Laparoscopic Donor Nephrectomy in Living Donors with a History of Abdominal Surgery: A Retrospective Cohort Study

Background

Hand-assisted laparoscopic donor nephrectomy (HALDN) is frequently performed in living kidney transplantation donors. This study investigated the efficacy and safety of HALDN for living donors with abdominal surgical histories.

Material/Methods

A total of 573 living kidney donors underwent donor nephrectomies for living donor kidney transplantation between January 2008 and May 2015. Eighteen donors underwent open donor nephrectomy and were excluded from analyses. Left HALDN was performed in 533 donors, including 44 donors with abdominal surgical histories and 489 donors without abdominal surgical histories. Right HALDN was performed in 22 donors, including 11 donors with abdominal surgical histories and 11 donors without abdominal surgical histories. Graft quality including the lengths of arteries, veins and ureters, time to initial urination, recipient complications, and recipient estimated glomerular filtration rate (eGFR) and operation quality including warm ischemic time, blood loss, operation duration, donor complications and donor eGFR, were compared between donors with and without abdominal surgical histories in the left and right HALDN groups.

Results

The metrics of graft and operation quality were similar between living kidney donors with and without a history of abdominal surgery who underwent left or right HALDN.

Conclusions

The efficacy and safety of HALDN were not impaired by abdominal surgical histories.

Retrograde ureteric stent insertion from percutaneous suprapubic access to the bladder in renal transplant recipients with ureteric stenosis: a novel minimally invasive technique

Background

Ureteric stricture is a common and salvaging complications after renal transplantation. Two treatment methods are usually used, retrograde ureteral stent placement and percutaneous nephrostomy. The former has a higher failure rate, the latter has a great risk. Therefore, a safe and reliable treatment is needed.

Case presentation

A technique of retrograde insertion of ureteral stent was established, which was applicable in three transplant recipients with post-transplant ureteral stenosis, and the data was retrospectively recorded. The patients are 2 men and 1 woman, ages 44, 27 and 32 years. These patients underwent a total of five times of retrograde insertion of ureteral stent between 2018 and 2019. None of these patients had any postoperative complication, but all patients had complete recovery from oliguric status within two weeks.

Conclusions

The retrograde ureteric stent insertion by percutaneous suprapubic access to the bladder (RUS-PSAB) was demonstrated feasibility and safety in a case series with short-term follow-up. However, larger prospective studies are needed.

Risk Factors for Anastomosis Leakage After Kidney Transplantation

Purpose

Kidney transplantation is one of the best treatment options for end-stage renal disease with an incidence of urologic complications of 2.5 to 30%. One of the most serious and frequent urological complications is urinary leakage from ureteroneocystostomy anastomosis. The purpose of this study was to evaluate risk factors of urinary leakage from ureteroneocystostomy anastomosis after kidney transplantation.

Patients and Methods

A retrospective study was performed on patients who received kidney transplantation and were diagnosed with urinary leakage thereafter based on renal scan or drain creatinine per serum creatinine compared with patients in control group. Risk factor assessment was based on inpatient and outpatient information from hospital database.

Results

From 459 patients who received kidney transplantation in 2016-2018, there were 20 patients who were diagnosed with urinary leakage after they underwent ureteroneocystostomy anastomosis. The significant risk factors for anastomosis leakage were size of suture materials and duration of ureteral stent insertion. No statistically significant difference in other factors such as underlying disease, surgical technique or duration of urinary catheter was found. About overall urological complication, gender and body mass index significantly affected the outcome.

Conclusion

The rate of urinary leakage complications was found to be about 4.36%. The risk factors of overall complication comprised gender and body mass index. Although a lot of previous studies revealed many risk factors that could affect urinary leakage, size of suture materials and duration of ureteral stent insertion were the significant risk factors in our study. Proper consideration should be given to the size of suture materials and optimal duration of ureteral stent.

Urologic complications in renal transplants

Urologic complications of renal transplant occur commonly and can have significant impact on graft function, survival, and patient morbidity. This review examines the prevalence of urologic complications, risk factors, diagnosis and options for management of the most common urologic complications.