An Update on Early Urological Complications in Kidney Transplantation: A National Cohort Study

Single-port robotic-assisted ureteral reconstruction for management of strictures after renal transplantation

Ureteral strictures are a common and often challenging complication of renal transplantation. The use of single-port (SP) robotic-assisted laparoscopic surgery is a novel approach in the management of these patients. Here we describe 3 patients with stricture of the transplant ureter causing hydronephrosis and allograft dysfunction, whose ureteral reconstructions were successfully performed using the SP robotic-assisted laparoscopic approach. Two patients underwent transplant-to-native ureteroureterostomy and 1 patient underwent ureteroneocystostomy. We demonstrate that the use of concurrent ureteroscopy and near-infrared fluorescence enables safe and rapid identification of native and transplant ureters. In addition, side-to-side anastomosis of transplant-to-native ureters allows for preservation of ureteral vasculature. In this limited series, the SP robotic platform demonstrates great promise in simplifying and streamlining our approach to ureteral strictures in this patient population.

Postoperative Events in Incompatible Living Donor Kidney Transplant Recipients Undergoing Prior Desensitization

BACKGROUND

Living donor kidney transplantation (LDKT) is one of the best options for patients with chronic renal failure, but approximately one-third of cases are limited by incompatibility ABO and/or HLA between recipient and donor. This study aims to analyze the surgical complications and bleeding events presented in ABO-incompatible (ABOi) and HLA-incompatible (HLAi) patients within a pre-transplant desensitization program compared with ABO-compatible (ABOc) recipients.

MATERIAL AND METHODS

We performed a retrospective analysis of ABOi and HLAi recipients undergoing LKDT between 2009 and 2019, resulting in a total of 62 patients that we compared with the same number of ABOc performed consecutively before 2019. The following variables were analyzed: surgical complications, presence, size and rate of reintervention of peri-graft hematomas, and number of transfusions received in the postoperative period.

RESULTS

No statistical differences were shown in donor and recipient age, BMI, or sex; in the case of pre-surgical hematocrit, the ABOi group presented slightly lower figures. In the incompatible group (ABOi + HLAi), we found a greater number of postoperative surgical complications when analyzing the number of hematomas, size, need for surgical reintervention, and the number of blood units transfused; incompatible patients showed higher rates of hematomas, need for surgical reinterventions, and transfused units (P < .05).

CONCLUSION

Desensitized patients need more transfusions, have a greater number and size of hematomas, and have higher reintervention rates. Although these are present in greater numbers, we did not observe statistically significant differences in the number of surgical complications.

Improving Surgical Safety in Living Donor Renal Transplantation With Antiseptic Skin Preparation, Bladder Irrigation, Corner-Saving Vascular Anastomosis, DJ Stenting, and Extravesical Ureteroneocystostomy Modifications: A Comprehensive Approach

Introduction The antiseptic skin preparation, bladder irrigation, corner-saving vascular anastomosis, DJ stenting, and extravesical ureteroneocystostomy (ABCDE) approach encompasses a range of modifications applied during different stages of the surgical procedure in renal transplantation. These modifications include the following: A, antiseptic skin preparation sequentially with cetrimide 3.35%, chlorhexidine scrub 4%, spirit, and povidone-iodine 10%; B, bladder irrigation with amikacin and betadine solution; C, corner-saving end-to-side vascular anastomosis; D, DJ stenting with early postoperative removal within three weeks; and E, extravesical ureteroneocystostomy using our institute's modified Lich-Gregoir technique. Methods This prospective observational study was conducted at our institution between March 2021 and May 2023. Data were collected from the patients' medical records and analyzed using Statistical Package for the Social Sciences (SPSS) (IBM SPSS Statistics, Armonk, NY, USA). Statistical tests, including t-test, Mann-Whitney test, chi-square test, and Fisher's exact test, were used for analysis. The study assessed various recipient, donor, intraoperative, and post-transplant factors, as well as surgical complications and stent-related factors. Results Out of 72 renal transplantations, 12 (16.6%) had the following surgical complications: urinary (n = 4; 5.5%), wound-related (n = 3; 4.1%), and lymphocele (n = 5; 6.9%). The most common complications were lymphocele (n = 5; 6.9%) and urinary leak (n = 4; 5.5%). Surgical complications were more common in male recipients (91.6% versus 8.3%), as well as in recipients with longer dialysis duration (24 ± 17 versus 11.0 ± 7 months) and had extended hospitalization time (16.4 ± 8.6 versus 8.0 ± 2.9 days) (p < 0.05). Wound infection correlated with longer surgeries (>300 minutes) and other complications. Lymphocele patients had higher drain output (>500 mL) on day 1 and longer hospital stays (>15 days). Urinary tract infections (UTIs) were linked to dialysis duration (>24 months), diabetes, and longer indwelling times of DJ stents and urinary catheters. Early DJ stent removal (<3 weeks) reduced UTI incidence and symptoms (p < 0.05). All complications were categorized as minor (3a or less), according to the Clavien-Dindo classification. Conclusion The modified ABCDE surgical approach in renal transplantation decreased the complications, showing favorable outcomes compared to those in the literature.

Ureteral Stenosis and Fistula after Kidney Transplantation

INTRODUCTION

Ureteral complications after kidney transplantation are frequent and may have a negative impact on morbidity and graft function. Treatment modalities include conservative, endourological, and surgical techniques, with variable outcomes. The purpose of this study was to report the incidence, characteristics, treatment, and outcomes of ureteral complications at our center.

METHODS

Retrospective study of kidney transplants performed at our unit between 2015 and 2020, analyzing incidence, characteristics, treatment, and outcomes of ureteral stenoses and fistulas.

RESULTS

Of 648 kidney transplants, we present 3.24% stenosis and 2.16% ureteral fistulas, with a mean time from transplantation of 101.4 and 24.4 days, respectively. Primary treatment was open surgical repair in 52.4% stenosis and 100% fistulas, with a success rate of 90.9% and 71.4%, respectively. Anterograde balloon dilatations were performed in 33.3% of stenosis with 40% success. Three patients required surgery as a secondary approach with 100% success. Major complications (Clavien-Dindo III) were observed in 18.5% following surgical repair. After a mean follow-up of 31.1 ± 20.9 months, we observe 88.6% of functioning grafts. We found no significant differences in graft survival between patients with or without ureteral complications (p 0.948).

CONCLUSION

Surgical repair of ureteral complications offers satisfactory results with low associated morbidity. Endourological techniques are less effective and should be reserved for selected cases. With adequate management, there is no impact on graft survival.

Relationship between Cytomegalovirus Viremia and Long-Term Outcomes in Kidney Transplant Recipients with Different Donor Ages

OBJECTIVES

To explore the Cytomegalovirus (CMV) burden on the long-term post-transplant course in different donor ages, we evaluated the incidence and risk factors for CMV in our kidney-transplanted patients (KTs) with extensive adoption of expanded-criteria donors (ECDs).

METHODS

Retrospective evaluation of 929 consecutive first KTs (49.5% receiving an organ from a donor ≥ 60 years) performed between 01-2003 and 12-2013. Overall survival was estimated using Kaplan-Meier curves; cumulative incidence function was additionally analyzed to consider the potential role of death with a functioning graft as a competitive event with graft dysfunction and to avoid overestimation. Apart from regular DNAemia monitoring in all patients, prophylaxis was adopted in high-risk groups (D+/R- or recipients of anti-thymocyte globulin induction), with pre-emptive therapy in the remaining groups.

RESULTS

CMV incidence was 19.5% (4-34.9% according to serostatus combination: D-/R-, D-/R+, D+/R+, D+/R-). Donor and recipient age, recipient pre-transplant hypertension, DR antigen compatibility, cold ischemia time, and post-transplant early complications, including rejection, urologic and renal artery stenosis, and lower renal function and proteinuria ≥ 0.5 g/day at one year after KT were associated with CMV. CMV determined lower death-censored graft survival (DCGS) (p < 0.01), with a prominent effect in R+ (p < 0.01) and without impact in R- (p = 0.32 in D-/R- and p = 0.006 in D+/R-). Interestingly, CMV occurrence influenced DCGS only in KTs who received grafts from donors < 50 or 50-69 years old (p < 0.01), while it was not significant with older donors (p = 0.07). The analysis of the cumulative incidence of graft loss accounting for death as a competing risk confirmed all these findings. In multivariate analysis, CMV replication/disease in the first year was an independent predictor for DCGS (HR 1.73 [1.3-2.3]).

CONCLUSIONS

In a large population with extensive ECD adoption, CMV viremia in the first year demonstrates its harmful effect with an independent role for graft loss and significant impact among R+ recipients and KTs with donors < 70 years.

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.

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.

Pretransplant BMI Significantly Affects Perioperative Course and Graft Survival after Kidney Transplantation: A Retrospective Analysis

Background. The number of kidney transplant recipients (KTRs) with overweight and obesity is increasing. It was shown that obesity is related to inferior patient and graft survival. We aimed to analyze intraoperative parameters and postoperative short and long-term course of kidney transplantation (KT) in body mass index (BMI)-stratified cohorts of KTRs. Methods. A retrospective analysis of a prospectively built database of 433 KTRs from 2014 to 2017 from a single transplant center was performed. The objective of the study was to analyze the association between BMI at the time of transplantation with intraoperative parameters, adverse events in early postoperative course, and the overall mortality and graft loss in BMI-stratified cohorts: normal (18.5 and 24.9 kg/m2), overweight (25−29.9 kg/m2) and obese (≥30 kg/m2). Results. Obesity was related to longer total procedure time (p = 0.0025) and longer warm ischemia time (p = 0.0003). The postoperative course in obese patients was complicated by higher incidence of DGF (delayed graft function), early surgical complications (defined as surgical complications <30 days from KT), reoperation rate, vascular complications, incidence of lymphocele and wound dehiscence. There was no difference between the normal weight and overweight KTRs. The one-month kidney function (p = 0.0001) and allograft survival (p = 0.029) were significantly inferior in obese patients with no difference between normal weight and overweight patients. One-year death-censored graft survival was better in patients with BMI < 30 (88.6 vs. 94.8% p = 0.05). BMI was a significant predictor of graft loss in univariate (p = 0.04) but not in multivariate analysis (p = 0.09). Conclusion. Pretransplant obesity significantly affects the intraoperative and postoperative course of kidney transplantation and graft function and survival. The course of transplantation of overweight is comparable to normal BMI KTRs, and presumably pretransplant weight reduction to the BMI < 30 kg/m2 may improve the short-term postoperative course of transplantation as well as may improve graft survival. Thus, pretransplant weight reduction in obese KTRs may significantly improve the results of kidney transplantation. Metabolic surgery may play a role in improving results of KT.

A STENTLESS MODIFIED LICH-GREGOIR TECHNIQUE FOR SAFE EARLY BLADDER CATHETER REMOVAL IN LIVING AND DECEASED KIDNEY TRANSPLANTS

OBJECTIVES

To describe a stentless modified Lich-Gregoir technique (mLG) for ureteroneocystostomy in renal transplantation (RT), with early bladder catheter (BC) removal (under 48 hours), and compare the postoperative results with those of the traditional technique (LG) with routine bladder catheter removal (4 to 5 days). The modification consists of maintaining a thin layer of detrusor fibers covering the bladder mucosa during dissection, which is incorporated into the anastomosis to reinforce the ureteroneocystostomy.

MATERIALS AND METHODS

This retrospective cohort study compared the postoperative outcomes of 100 consecutive patients who underwent mLG with early removal of BC between October 2018 to November 2019 with those of a historical cohort of 165 consecutive patients transplanted using stentless LG and routine removal of BC, who underwent surgery between July 2017 and September 2018. All transplants were performed by the same surgeon. Follow-up was 6 months.

RESULTS

Demographic characteristics were comparable, although patients in the mLG group had a higher mean preoperative urine volume (911±753.8mL vs. 629±638.6mL, p=0.016). Patients in the mLG group successfully underwent early BC removal (2.2±0.9 vs. 4.8±4.8 days, p<0.001), with no differences in the incidence of surgical or clinical complications, including urine leaks (1 vs. 3%, p=0.284). In addition, mLG patients presented a shorter mean length of hospital stay (6.5±5.0 vs. 7.1±6.2 days, p=0.023).

CONCLUSION

This stentless modified Lich-Gregoir technique enables safe early bladder catheter removal and is associated with reduced hospital length of stay.

Transplant Ureteral Stenosis after Renal Transplantation: Risk Factor Analysis

INTRODUCTION

The results of kidney transplants have improved dramatically in recent years, leading to reduced morbidity and mortality. Despite continuous improvements, urological complications occur at a rate of 2.6%-15%. Ureteral stenosis of graft ureters is the most common complication, with a probability of 0.5%-6.3%. This study aimed to determine the incidence of ureteral stenosis after kidney transplantation and identify risk factors that distinguish transplant patients with and without ureteral stenosis.

METHODS

This study retrospectively analyzed patients who had undergone kidney transplantation at the Department of Urology of the Friedrich-Alexander University Erlangen-Nuremberg between 2001 and 2015. Forty-seven patients developed ureteral stenosis during the operation. Most of the ureteral stenosis cases occurred in the first 4 months after transplantation. Kaplan-Meier analysis and the log-rank test were used to calculate the cumulative risk, and the Mann-Whitney U test was used nonparametrically. The significance level was set at p < 0.05.

RESULTS

Statistical analysis showed that residual diuresis (p = 0.008), cold ischemia time (CIT) (p = 0.040), the body mass index (p = 0.027), and donor serum creatinine value (p = 0.039) showed a significantly different distribution between recipients with or without ureteral stenosis after kidney transplantation. In multivariate Cox's regression modeling, residual diuresis and the donor serum creatinine level were identified as the only independent predictors of patients' stenosis-free survival.

CONCLUSION

Urological complications not diagnosed and treated in time endanger the success of kidney transplantation. After evaluating the kidney transplantation data of the patients at the Transplant Center Erlangen-Nuremberg from 2001 to 2015, residual diuresis, CIT, the body mass index, and donor serum creatinine value were found to influence the development of ureteral stenosis.

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.

Update on the Management of Urological Problems Following Kidney Transplantation

Urological problems in kidney transplant recipients are not limited only to posttransplantation urological complications. These problems are a cause of significant patient mortality and morbidity that have wide-ranging effects on graft survival throughout the entire life of the graft. Ultimately, the transplant comprises a major portion of the urinary system; therefore, the transplant team should be prepared for foreseeable and unforeseeable urological problems in the short and long terms. These mainly include postoperative urological complications (urine leakage, ureteral stenosis, and vesicoureteral reflux), bladder outlet obstruction, and graft urolithiasis. In recent years, significant advances have been made in the management of urological complications, especially due to advances in endourologic interventions. The aim of this review is to summarize the management of urological problems after kidney transplantation in the context of the current literature.

Urological Complications in Kidney Transplant Recipients: Analysis of the Risk Factors and Impact on Transplant Outcomes in the Era of “Extended Criteria Donors”

Urological complications (UC) following kidney transplantation (KT) are associated with increased morbidity. The aim of this study is to evaluate the risk factors for UC in the era of “extended criteria donors” (ECD) and their impact on patient and graft survivals. A retrospective monocentric study of all patients undergoing KT from 2010 to 2019 with a follow-up ≥30 days was performed. Out of 459 patients (males: 296 (64.5%); age: 57 (19–77) years) enrolled, 228 (49.7%) received ECD organs, moreover, 166 (67.2%) grafts had a cold ischemia time ≥10 h. UCs were reported in 32 (7%) patients. In 21 (65.6%) cases UC occurred within 3 months post-KT and 24 (5.2%) were associated with early urinary tract infection (UTI). The overall 5 year patient and graft survival rates were 96.5% and 90.6%, respectively. UC decreased graft survival (UC-group: 75.0% vs. noUC-group: 91.8%, p < 0.001), especially if associated with early UTI (UC-group: 71.4% vs. noUC-group: 77.8%, p < 0.001). At multivariate analysis, early UTI after KT (OR: 9.975, 95%-IC: 2.934–33.909, p < 0.001) and delayed graft function (DGF) (OR: 3.844, 95%-IC: 1.328–11.131, p: 0.013) were significant risk factors for UC, while ECD graft did not increase the risk of post-transplant UC. ECD grafts are not associated with UC. DGF and early UTI post-KT increase the risks of UC and reduce graft survival in the long-term. Therefore, aggressive management of early post-transplant UTI and strategies to reduce DGF incidence, such as machine preservation, are essential to prevent UC after KT.

Recipient and renal allograft survival following living related-donor transplantation: a single center experience

Background

Despite improvements in surgical techniques of renal transplantation, still surgical complications remain a big challenge that might affect the post-transplant recipient and graft outcome. The aim of the current study was to retrospectively assess the surgical complications following living related kidney transplants in our center from 1990 to 2012 and determine their impact on long term recipient and graft survival.

Methods

We conducted a retrospective study of all live related-donor kidney transplants performed at our tertiary referral center between June 1990 and December 2012. Data regarding recipient demographics, details of surgical techniques, any reported complications and cumulative recipient and graft survival was analyzed.

Results

One hundred and four patients were included in the study whom we had access to their complete hospital records and they didn’t miss follow up. There were 41 surgical complications reported in 37 recipients, prevalence of 35.5%. Vascular and urologic complications were reported in 17(16.3%) and 11 (10.5%) recipients respectively. Lymphocele was post-operatively diagnosed in nine (8.7%) recipients. Recipient survival at 1 year and 5-year were 100% and 97% respectively. Graft survival at 1 year and at 5 years were 96% and 85.5% respectively. Surgical complications mentioned, other than renal artery thrombosis, had no statistically significant impact on the graft and recipient survival.

Conclusion

Although surgical complications post-transplantation are not rare, the resulting morbidity can be minimized by prompt management of complications. In general, the existence of surgical complications did not impact recipient or graft survival.