Stenting the ureteroneocystostomy reduces urological complications in kidney transplantation: a noninferiority randomized controlled trial, SPLINT trial.

The role of ureteral stents in living-donor kidney transplantation remains uncertain. In this randomized controlled trial (SPLINT), we compared urological complications in living-donor kidney transplantations performed with or without stents. We included 200 consecutive patients that received living-donor kidney transplantations at the Erasmus MC, University Medical Center, Rotterdam. Patients (124 males, 76 females, mean age 54 ± 13) were randomized for suprapubic externalized single J stents (N = 100) or no stent (N = 100). The primary outcome was the probability of a percutaneous nephrostomy insertion (PCN) during a 12-month follow-up. To assess whether no stenting is noninferior to stenting, we allowed the probability of a PCN to increase by at most 5% (this is the noninferiority margin). Baseline characteristics were comparable between groups. In the no-stent group, there were more PCN insertions, 14% (95% CI 4.3-23.7%); urinary leakages, 12% (95% CI 5.4-21.3%); and surgical re-interventions because of urological complications, 8% (95% CI 1.5-14.5%). The stent group had more hematuria, 26% (95% CI 13.1-38.9%); and graft rejections, 15% (95% CI 2.7-27.3%). Patients in both groups had similar mean GFRs at several time points. Besides a better Euro-Qol-5D in the no-stent group at 2 and 6 weeks postoperative, similar quality of life was reported based on SF-36 and Euro-Qol-5D scores. In this trial, noninferiority has not been demonstrated for no-stent placement in relation to the number urological complications.

Cell-free MicroRNA miR-505-3p in Graft Preservation Fluid Is an Independent Predictor of Delayed Graft Function After Kidney Transplantation.

BACKGROUND: Delayed graft function (DGF), a common complication after transplantation of deceased donor kidneys, affects both short- and long-term outcomes. Currently available biomarkers during graft preservation lack sensitivity in predicting risk for DGF. The aim of this study is to identify cell-free micro ribonucleic acid (miRNA) biomarkers in graft preservation fluid predictive of DGF after kidney transplantation. METHODS: Vascular bed preservation fluid was collected from 48 kidney grafts from donation after circulatory death (DCD) or donation after brain death (DBD) donors. miRNA profiles were determined by polymerase chain reaction (PCR) array (n = 8) and validated by reverse transcription and quantitative PCR (n = 40). Graft function posttransplantation was defined as immediate good function (IF) or DGF. RESULTS: A total of 223 miRNAs fulfilled the preset parameters (Ct < 40 in 3 or more samples) and were included in the analysis. Thirty-two miRNAs were significantly different between DGF and IF kidney grafts (P < 0.05) but, after correction for multiple testing, only miR-505-3p remained significant. The significant association of high miR-505-3p levels with DGF was confirmed in an independent validation cohort using conventional reverse transcription and quantitative PCR detection. Multivariate analyses showed miR-505-3p as an independent predictor for DGF (odds ratio, 1.12; P = 0.028). If stratified for donor type, miR-505-3p levels remained significantly different between IF and DGF in DCD grafts (P < 0.01), but not in DBD grafts. Receiver operating characteristic curve analysis showed a high sensitivity and specificity (area under the curve, 0.833). CONCLUSIONS: In DCD grafts, high levels of miR-505-3p in preservation fluid are associated with increased risk of DGF after kidney transplantation. Further study is required to confirm the utility of cell-free miR-505-3p as prognostic biomarker for DGF.

Antegrade Balloon Dilatation as a Treatment Option for Posttransplant Ureteral Strictures: Case Series of 50 Patients.

OBJECTIVES: The aim of this study was to investigate the effects of antegrade balloon dilatation on ureteral strictures that developed after kidney transplant. MATERIALS AND METHODS: The hospital databases of the Erasmus Medical Center (Rotterdam, The Netherlands) and the Academic Medical Center (Amsterdam, The Netherlands) were retrospectively screened for patients who underwent balloon dilatation after kidney transplant. Balloon dilatation was technically successful whenever it was able to pass the strictured segment with the guidewire followed by balloon inflation; the procedure was clinically successful if no further interventions (for example, surgical revision of the ureteroneocystostomy or prolonged double J placement) were necessary. RESULTS: Fifty patients (2.4%) of 2075 kidney transplant recipients underwent antegrade balloon dilatation because of urinary outflow obstruction. Median time between transplant and balloon dilatation was 3 months (range, 0-139 mo). In 43 patients (86%), balloon dilatation was technically successful. In the remaining 7 patients (14%), it was impossible to pass the strictured segment with the guidewire. In 20 of 43 patients (47%) having a technically successful procedure, the procedure was also clinically successful, with median follow-up after balloon dilatation of 35.5 months (range, 0-102 mo). We did not identify any patient or stricture characteristic that influenced the outcome of treatment. CONCLUSIONS: Balloon dilatation is a good option for ureter stricture treatment after kidney transplant as it is minimal invasive and can prevent surgical exploration in almost 50% of cases.

Urinary Tract Infections After Kidney Transplantation: A Risk Factor Analysis of 417 Patients.

BACKGROUND The aim of this study was to evaluate the number of urinary tract infections (UTI) that occur after kidney transplantation (KT) and to identify possible risk factors for development of a UTI. MATERIAL AND METHODS We retrospectively analyzed all KTs performed between January 2012 and December 2013 in the Erasmus University Medical Center, Rotterdam. UTI was scored if: (1) a patient had a urine culture with no more than 2 species of microorganisms, (2) at least 1 of which was a bacterium of ≥10^5 CFU/mL, (3) which was treated with antibiotics, and (4) which occurred within 3 months after KT. RESULTS A total of 417 patients were transplanted from January 2012 until December 2013. A UTI developed in 115 (28%), after a median of 13 days from transplantation (range: 3-82 days). The most common causative agent was Escherichia coli, followed by Enterococcus faecalis, Enterococcus faecium, and Klebsiella pneumoniae. The variables that were independently related to a UTI were female gender (OR 3.58, 95%CI 2.16-5.91), recipients age >60 y (OR 2.12, 95%CI 1.28-3.48), percutaneous nephrostomy placements (OR 6.29, 95%CI 3.35-11.85), and surgical re-interventions (OR 2.12, 95%CI 1.04-4.32). Mean glomerular filtration rate was significantly lower in the group of patients with a UTI at 3, 6, 9, and 12 months postoperatively compared to those patients who did not have a UTI. CONCLUSIONS We conclude that a UTI after KT is a common problem. We identified independent risk factors for the development of a UTI. UTI is associated with a GFR decrease postoperatively.

Proteins in Preservation Fluid as Predictors of Delayed Graft Function in Kidneys from Donors after Circulatory Death.

BACKGROUND AND OBJECTIVES: Kidney transplantation is the preferred treatment for ESRD, and donor kidney shortage urges proper donor-recipient matching. Zero-hour biopsies provide predictive values for short- and long-term transplantation outcomes, but are invasive and may not reflect the entire organ. Alternative, more representative methods to predict transplantation outcome are required. We hypothesized that proteins accumulating in preservation fluid during cold ischemic storage can serve as biomarkers to predict post-transplantation graft function. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Levels of 158 proteins were measured in preservation fluids from kidneys donated after circulatory death (Maastricht category III) collected in two Dutch centers (University Medical Center Utrecht and Erasmus Medical Center Rotterdam) between 2013 and 2015. Five candidate biomarkers identified in a discovery set of eight kidneys with immediate function (IF) versus eight with delayed graft function (DGF) were subsequently analyzed in a verification set of 40 additional preservation fluids to establish a prediction model. RESULTS: Variables tested for their contribution to a prediction model included five proteins (leptin, periostin, GM-CSF, plasminogen activator inhibitor-1, and osteopontin) and two clinical parameters (recipient body mass index [BMI] and dialysis duration) that distinguished between IF and DGF in the discovery set. Stepwise multivariable logistic regression provided a prediction model on the basis of leptin and GM-CSF. Receiver operating characteristic analysis showed an area under the curve (AUC) of 0.87, and addition of recipient BMI generated a model with an AUC of 0.89, outperforming the Kidney Donor Risk Index and the DGF risk calculator, showing AUCs of 0.55 and 0.59, respectively. CONCLUSIONS: We demonstrate that donor kidney preservation fluid harbors biomarkers that, together with information on recipient BMI, predict short-term post-transplantation kidney function. Our approach is safe, easy, and performs better than current prediction algorithms, which are only on the basis of clinical parameters.

Minimizing the Number of Urological Complications After Kidney Transplant: A Comparative Study of Two Types of External Ureteral Stents.

OBJECTIVES: The aim of this study was to evaluate the effects of 2 types of external ureteral stents on the number of urological complications after kidney transplant. MATERIALS AND METHODS: Data were retrospectively collected from 366 consecutive transplants performed between January 2013 and January 2015 in our hospital, in which an external ureteral stent was placed during surgery and removed after 9 days. Urological complications were defined as urinary leakage or ureteral stenosis requiring percutaneous nephrostomy placement. RESULTS: A total of 197 patients received a straight stent with 2 larger side holes (type A; 8F "Covidien" tube; Covidien, Dublin, Ireland) and 169 patients received a single J stent with 7 smaller side holes (type B; 7F "Teleflex" single J stent; Teleflex Medical, Athlone, Ireland). We found a significantly higher number of percutaneous nephrostomy placements with type A stents, with 34 (17%) versus 16 (9%) in type B (P = .030). Reason for percutaneous nephrostomy placement, occurrence of stent dysfunction, and need for early removal (< 8 days) were equal in both groups (P = .397), whereas incidence of rejection and urinary tract infection were higher in type B stent group. Patient and graft survival did not differ between the groups. CONCLUSIONS: Use of the type B stent was associated with less urological complications compared with the type A stent.

Incidence, risk factors, and treatment of incisional hernia after kidney transplantation: An analysis of 1,564 consecutive patients.

BACKGROUND: The objective was to evaluate the incidence and treatment of incisional hernia after kidney transplantation and to identify potential risk factors. METHODS: A retrospective cohort study was performed. All kidney transplant recipients between 2002 and 2012 were included. Two groups were identified: patients with and without incisional hernia. An analysis of risk factors for the development of incisional hernia was performed. RESULTS: A total of 1,564 kidney recipients were included. Fifty patients (3.2%) developed incisional hernia. On univariate analysis, female sex (54 vs 35%), body mass index (BMI) >30 kg/m(2) (38 vs 17%), concurrent abdominal wall hernia (30 vs 16%), multiple explorations of the ipsilateral iliac fossa (38 vs 19%), left iliac fossa implantation (36 vs 24%), history of smoking (72 vs 57%), and duration of the kidney transplantation procedure (210 vs 188 minutes) were associated with the development of incisional hernia (P < .05 each). In multivariate analyses, female sex (hazard ratio [HR] 2.6), history of smoking (HR 2.2), obesity (BMI >30; HR 2.9), multiple explorations of the ipsilateral iliac fossa (HR 2.0), duration of operation (HR 1.007), and concurrent abdominal wall hernia (HR 2.3) were independent risk factors. Twenty-six of 50 patients (52%) underwent operative repair, of whom 9 (35%) required emergency repair. CONCLUSION: The incidence of incisional hernia after kidney transplantation with a median follow-up of 59 months is 3.2%. Obesity (BMI >30), female sex, concurrent abdominal wall hernias, history of smoking, duration of surgery, and multiple explorations were independent risk factors for the development of incisional hernia after kidney transplantation. Attempts at preventing incisional hernias based on these risk factors should be explored.

Ureteral length in live donor kidney transplantation; Does size matter?

The aim of this study was to evaluate the role of ureteral length on urological complications. Data were retrospective collected from the INEX-trial database, a RCT to compare the intravesical to the extravesical ureteroneocystostomy. Ureteral length was measured in 198 recipients and used to divide recipients into three categories based on interquartile ranges: short (≤8.5 cm), medium (8.6-10.9 cm) and long ureters (≥11 cm). Urological complications were defined as the number of percutaneous nephrostomy placements (PCN). Fifty recipients fell into the short, 98 into the medium and 50 recipients into the long ureter category. Median follow-up was 26 (range 2-45) months. There was no significant difference in number of PCN placements between the categories. There were 9 (18%) PCN placements in the short ureter category, 21 (20%) in medium ureter category and 10 (21%) in the long ureter category, P = 0.886. Risk factor analysis for gender, arterial multiplicity and type of ureteroneocystostomy showed no differences in PCN placements between the three ureteral length categories. We conclude that ureteral length alone does not seem to influence the number of urological complications.