Multiomic profiling of transplant glomerulopathy reveals a novel T-cell dominant subclass.

Kidney transplant (KTx) biopsies showing transplant glomerulopathy (TG) (glomerular basement membrane double contours (cg) > 0) and microvascular inflammation (MVI) in the absence of C4d staining and donor-specific antibodies (DSAs) do not fulfill the criteria for chronic active antibody-mediated rejection (CA-AMR) diagnosis and do not fit into any other Banff category. To investigate this, we initiated a multicenter intercontinental study encompassing 36 cases, comparing the immunomic and transcriptomic profiles of 14 KTx biopsies classified as cg+MVI DSA-/C4d- with 22 classified as CA-AMR DSA+/C4d+ through novel transcriptomic analysis using the NanoString Banff-Human Organ Transplant (B-HOT) panel and subsequent orthogonal subset analysis using two innovative 5-marker multiplex immunofluorescent panels. Nineteen genes were differentially expressed between the two study groups. Samples diagnosed with CA-AMR DSA+/C4d+ showed a higher glomerular abundance of natural killer cells and higher transcriptomic cell type scores for macrophages in an environment characterized by increased expression of complement-related genes (i.e., C5AR1) and higher activity of angiogenesis, interstitial fibrosis tubular atrophy, CA-AMR, and DSA-related pathways when compared to samples diagnosed with cg+MVI DSA-/C4d-. Samples diagnosed with cg+MVI DSA-/C4d- displayed a higher glomerular abundance and activity of T cells (CD3+, CD3+CD8+, and CD3+CD8-). Thus, we show that using novel multiomic techniques, KTx biopsies with cg+MVI DSA-/C4d- have a prominent T-cell presence and activity, putting forward the possibility that these represent a more T-cell dominant phenotype.

Red blood cells as oxygen carrier during normothermic machine perfusion of kidney grafts: Friend or foe?

Renal ex vivo normothermic machine perfusion (NMP) is under development as an assessment tool for high-risk kidney grafts and as a means of achieving more physiologically accurate organ preservation. On-going hemolysis has been reported during NMP, as this technique relies on red blood cells for oxygen delivery. In this study, we confirm the occurrence of progressive hemolysis during 6-hour kidney NMP. NMP-associated erythrostasis in the glomeruli and in peri-glomerular vascular networks points to an interaction between the red blood cells and the graft. Continuous hemolysis resulted in prooxidative changes in the perfusate, which could be quenched by addition of fresh frozen plasma. In a cell-based system, this hemolysis induced redox stress and exhibited toxic effects at high concentrations. These findings highlight the need for a more refined oxygen carrier in the context of renal NMP.

The Influence of Hepatic Steatosis and Fibrosis on Postoperative Outcomes After Major Liver Resection of Perihilar Cholangiocarcinoma.

BACKGROUND: Surgical resection for perihilar cholangiocarcinoma (pCCA) is associated with high operative risks. Impaired liver regeneration in patients with pre-existing liver disease may contribute to posthepatectomy liver failure (PHLF) and postoperative mortality. This study aimed to determine the incidence of hepatic steatosis and fibrosis and their association with PHLF and 90-day postoperative mortality in pCCA patients. METHODS: Patients who underwent a major liver resection for pCCA were included in the study between 2000 and 2021 from three tertiary referral hospitals. Histopathologic assessment of hepatic steatosis and fibrosis was performed. The primary outcomes were PHLF and 90-day mortality. RESULTS: Of the 401 included patients, steatosis was absent in 334 patients (83.3%), mild in 58 patients (14.5%) and moderate to severe in 9 patients (2.2%). There was no fibrosis in 92 patients (23.1%), periportal fibrosis in 150 patients (37.6%), septal fibrosis in 123 patients (30.8%), and biliary cirrhosis in 34 patients (8.5%). Steatosis (≥ 5%) was not associated with PHLF (odds ratio [OR] 1.36; 95% confidence interval [CI] 0.69-2.68) or 90-day mortality (OR 1.22; 95% CI 0.62-2.39). Neither was fibrosis (i.e., periportal, septal, or biliary cirrhosis) associated with PHLF (OR 0.76; 95% CI 0.41-1.41) or 90-day mortality (OR 0.60; 95% CI 0.33-1.06). The independent risk factors for PHLF were preoperative cholangitis (OR 2.38; 95% CI 1. 36-4.17) and future liver remnant smaller than 40% (OR 2.40; 95% CI 1.31-4.38). The independent risk factors for 90-day mortality were age of 65 years or older (OR 2.40; 95% CI 1.36-4.23) and preoperative cholangitis (OR 2.25; 95% CI 1.30-3.87). CONCLUSION: In this study, no association could be demonstrated between hepatic steatosis or fibrosis and postoperative outcomes after resection of pCCA.

Long-Term Outcomes of Living Donor Liver Transplantation for Methylmalonic Acidemia.

BACKGROUND: Despite early diagnosis and medical interventions, patients with methylmalonic acidemia (MMA) suffer from multi-organ damage and recurrent metabolic decompensations. METHODS: We conducted the largest retrospective multi-center cohort study so far, involving five transplant centers (NCCHD, KUH, KUHP, ATAK, and EMC), and identified all MMA patients (n = 38) undergoing LDLT in the past two decades. Our primary outcome was patient survival, and secondary outcomes included death-censored graft survival and posttransplant complications. RESULTS: The overall 10-year patient survival and death-censored graft survival rates were 92% and 97%, respectively. Patients who underwent LDLT within 2 years of MMA onset showed significantly higher 10-year patient survival compared to those with an interval more than 2 years (100% vs. 81%, p = 0.038), although the death-censored graft survival were not statistically different (100% vs. 93%, p = 0.22). Over the long-term follow-up, 14 patients (37%) experienced intellectual disability, while two patients developed neurological complications, three patients experienced renal dysfunction, and one patient had biliary anastomotic stricture. The MMA level significantly decreased from 2218.5 mmol/L preoperative to 307.5 mmol/L postoperative (p = 0.038). CONCLUSIONS: LDLT achieves favorable long-term patient and graft survival outcomes for MMA patients. While not resulting in complete cure, our findings support the consideration of early LDLT within 2 years of disease onset. This approach holds the potential to mitigate recurrent metabolic decompensations, and preserve the long-term renal function.

Treatment of Renal Artery Aneurysm by ex situ Repair and Autotransplantation: A Nationwide Cohort Study.

INTRODUCTION: Renal artery aneurysm (RAA) is a rare vascular disease with a mortality rate of up to 80% upon rupture. This study aimed to investigate the safety and efficacy of ex situ repair and autotransplantation for endovascularly untreatable RAA. METHODS: A retrospective nationwide cohort study was conducted in RAA patients undergoing ex situ repair and autotransplantation in the Netherlands. Surgical techniques, postoperative complications, and graft outcomes were assessed. RESULTS: Ex situ repair was performed in 9 patients with 11 RAAs. Eight RAAs were located at the first bifurcation, one on the main trunk, one on the first branch, and one on the second branch. Nephrectomy was performed via laparoscopy (n = 7), robotic-assisted laparoscopy (n = 1), and laparotomy (n = 1). Postoperative complications were recorded in 4 patients, including bowel obstruction, delirium, pneumonia, and hydronephrosis due to double-J dislocation. The median estimated glomerular filtration rate was 83 mL/min/1.73 m2 pretransplant and 88 mL/min/1.73 m2 posttransplant. By an average follow-up of 32 months, 2 patients had died due to lung adenocarcinoma and stroke, while all autotransplanted kidneys had good patency and remained functional. CONCLUSIONS: Ex situ repair and autotransplantation are safe and feasible for endovascularly untreatable RAA cases. Larger cohorts with longer follow-up periods are necessary to further evaluate the role of this surgical approach.

Ipsilateral Aorto-Iliac Calcification is Not Directly Associated With eGFR After Kidney Transplantation: A Prospective Cohort Study Analyzed Using a Linear Mixed Model.

Aorto-iliac calcification (AIC) is a well-studied risk factor for post-transplant cardiovascular events and mortality. Its effect on graft function remains unknown. The primary aim of this prospective cohort study was to assess the association between AIC and estimated glomerular filtration rate (eGFR) in the first year post-transplant. Eligibility criteria were: ≥50 years of age or ≥30 years with at least one risk factor for vascular disease. A non-contrast-enhanced CT-scan was performed with quantification of AIC using the modified Agatston score. The association between AIC and eGFR was investigated with a linear mixed model adjusted for predefined variables. One-hundred-and-forty patients were included with a median of 31 (interquartile range 26-39) eGFR measurements per patient. No direct association between AIC and eGFR was found. We observed a significant interaction between follow-up time and ipsilateral AIC, indicating that patients with higher AIC scores had lower eGFR trajectory over time starting 100 days after transplant (p = 0.014). To conclude, severe AIC is not directly associated with lower post-transplant eGFR. The significant interaction indicates that patients with more severe AIC have a lower eGFR trajectory after 100 days in the first year post-transplant.

Real-time laser speckle contrast imaging measurement during normothermic machine perfusion in pretransplant kidney assessment.

OBJECTIVES: Normothermic machine perfusion (NMP) provides a platform for pre-transplant kidney quality assessment that is essential for the use of marginal donor kidneys. Laser speckle contrast imaging (LSCI) presents distinct advantages as a real-time and noncontact imaging technique for measuring microcirculation. In this study, we aimed to assess the value of LSCI in visualizing renal cortical perfusion and investigate the additional value of dual-side LSCI measurements compared to single aspect measurement during NMP. METHODS: Porcine kidneys were obtained from a slaughterhouse and then underwent NMP. LSCI was used to measure one-sided cortical perfusion in the first 100 min of NMP. Thereafter, the inferior renal artery branch was occluded to induce partial ischemia and LSCI measurements on both ventral and dorsal sides were performed. RESULTS: LSCI fluxes correlated linearly with the renal blood flow (R2 = 0.90, p < 0.001). After renal artery branch occlusion, absence of renal cortical perfusion could be visualized and semiquantified by LSCI. The overall ischemic area percentage of the ventral and dorsal sides was comparable (median interquartile range [IQR], 38 [24-43]% vs. 29 [17-46]%, p = 0.43), but heterogenous patterns between the two aspects were observed. There was a significant difference in oxygen consumption (mean ± standard deviation [SD], 2.57 ± 0.63 vs. 1.83 ± 0.49 mLO2 /min/100 g, p < 0.001), urine output (median [IQR], 1.3 [1.1-1.7] vs. 0.8 [0.6-1.3] mL/min, p < 0.05), lactate dehydrogenase (mean ± SD, 768 ± 370 vs. 905 ± 401 U/L, p < 0.05) and AST (mean ± SD, 352 ± 285 vs. 462 ± 383 U/L, p < 0.01) before and after renal artery occlusion, while no significant difference was found in creatinine clearance, fractional excretion of sodium, total sodium reabsorption and histological damage. CONCLUSIONS: LSCI fluxes correlated linearly with renal blood flow during NMP. Renal cortical microcirculation and absent perfusion can be visualized and semiquantified by LSCI. It provides a relative understanding of perfusion levels, allowing for a qualitative comparison between regions in the kidney. Dual-side LSCI measurements are of added value compared to single aspect measurement and renal function markers.

Antithrombotic Management in Adult Kidney Transplantation: A European Survey Study.

In kidney transplantation (KTx), renal graft thrombosis (RGT) is one of the main reasons for early graft loss. Although evidence-based guidance on prevention of RGT is lacking, thromboprophylaxis is widely used. The aim of this survey was to obtain a European view of the different thromboprophylactic strategies applied in KTx. An online 22-question survey, addressed to KTx professionals, was distributed by email and via platforms of the European Society for Organ Transplantation. Seventy-five responses (21 countries, 51 centers) were received: 75% had over 10 years' clinical experience, 64% were surgeons, 29% nephrologists, and 4% urologists. A written antithrombotic management protocol was available in 75% of centers. In 8 (16%) centers, respondents contradicted each other regarding the availability of a written protocol. Thromboprophylaxis is preferred by 78% of respondents, independent of existing antithrombotic management protocols. Ninety-two percent of respondents indicated that an anticipated bleeding risk is the main reason to discontinue chronic antithrombotic therapy preoperatively. Intraoperatively, 32% of respondents administer unfractionated heparin (400-10,000 international units with a median of 5,000) in selected cases. Despite an overall preference for perioperative thromboprophylaxis in KTx, there is a high variation within Europe regarding type, timing, and dosage, most likely due to the paucity of high-quality studies. Further research is warranted in order to develop better guidelines.

Expanding the living donor pool using domino liver transplantation: a systematic review.

INTRODUCTION: To this day, a discrepancy exists between donor liver demand and supply. Domino liver transplantation (DLT) can contribute to increasing the number of donor livers available for transplantation. METHODS: The design of this systematic review was based on the Preferred Reporting Items for Systematic Reviews (PRISMA). A qualitative analysis of included studies was performed. Primary outcomes were mortality and peri- and postoperative complications related to DLT. RESULTS: Twelve studies met the inclusion criteria. All included studies showed that DLT outcomes were comparable to outcomes of deceased donor liver transplantation (DDLT) in terms of mortality and complications. One-year patient survival rate ranged from 66.7% to 100%. Re-transplantation rate varied from 0 to 12.5%. Most frequent complications were related to biliary (3.7%-37.5%), hepatic artery (1.6%-9.1%), portal vein (12.5-33.3%) and hepatic vein events (1.6%), recurrence of domino donor disease (3.3%-17.4%) and graft rejection (16.7%-37.7%). The quality of the evidence was rated as moderate according to the Newcastle-Ottawa scale (NOS). CONCLUSION: DLT outcomes were similar to DDLT in terms of mortality and complications. Even though DLT will not solve the entire problem of organ shortage, transplant programs should always consider using this tool to maximize the availability of liver grafts.

The current status of stem cell-based therapies during ex vivo graft perfusion: An integrated review of four organs.

The use of extended criteria donor grafts is a promising strategy to increase the number of organ transplantations and reduce waitlist mortality. However, these organs are often compromised and/or damaged, are more susceptible to preservation injury, and are at risk for developing post-transplant complications. Ex vivo organ perfusion is a novel technology to preserve donor organs while providing oxygen and nutrients at distinct perfusion temperatures. This preservation method allows to resuscitate grafts and optimize function with therapeutic interventions prior to solid organ transplantation. Stem cell-based therapies are increasingly explored for their ability to promote regeneration and reduce the inflammatory response associated with in vivo reperfusion. The aim of this review is to describe the current state of stem cell-based therapies during ex vivo organ perfusion for the kidney, liver, lung, and heart. We discuss different strategies, including type of cells, route of administration, mechanisms of action, efficacy, and safety. The progress made within lung transplantation justifies the initiation of clinical trials, whereas more research is likely required for the kidney, liver, and heart to progress into clinical application. We emphasize the need for standardization of methodology to increase comparability between future (clinical) studies.

Risk of post-transplant cardiovascular events in kidney transplant recipients with preexisting aortoiliac stenosis.

Prediction of the risk of cardiovascular events (CVE's) is important to optimize outcomes after kidney transplantation. Aortoiliac stenosis is frequently observed during pre-transplant screening. We hypothesized that these patients are at higher risk of post-transplant CVE's due to the joint underlying atherosclerotic disease. Therefore, we aimed to assess whether aortoiliac stenosis was associated with post-transplant CVE's. This retrospective, single-center cohort study included adult kidney transplant recipients, transplanted between 2000 and 2016, with contrast-enhanced imaging available. Aortoiliac stenosis was classified according to the Trans-Atlantic Inter-Society Consensus (TASC) II classification and was defined as significant in case of ≥50% lumen narrowing. The primary outcome was CVE-free survival. Eighty-nine of 367 patients had significant aortoiliac stenosis and were found to have worse CVE-free survival (median CVE-free survival: stenosis 4.5 years (95% confidence interval (CI) 2.8-6.2), controls 8.9 years (95% CI 6.8-11.0); log-rank test P < .001). TASC II C and D lesions were independent risk factors for a post-transplant CVE with a hazard ratio of 2.15 (95% CI 1.05-4.38) and 6.56 (95% CI 2.74-15.70), respectively. Thus, kidney transplant recipients with TASC II C and D aortoiliac stenosis require extensive cardiovascular risk management pre-, peri,- and post-transplantation.

Screening, Management, and Acceptance of Patients with Aorto-Iliac Vascular Disease for Kidney Transplantation: A Survey among 161 Transplant Surgeons.

INTRODUCTION: Aorto-iliac vascular disease (AVD) is frequently found during the workup for kidney transplantation. However, recommendations on screening and management are lacking. We aimed to assess differences in screening, management, and acceptance of these patients for transplantation by performing a survey among transplant surgeons. Second, we aimed to identify center- and surgeon-related factors associated with decline or acceptance of kidney transplant candidates with AVD. METHODS: A survey was sent to transplant surgeons and urologists. The survey contained general questions (part I) and 2 patient-based cases (part II) with Trans-Atlantic Inter-Society Consensus (TASC) D and B AVD supported with videos of their CT scans. RESULTS: One hundred ninety-one (20.3%) participants responded; 171 were currently involved in kidney transplantation: 161 (94.2%) completed part I and 145 (84.8%) part II. Screening for AVD was often (38.5%) restricted to high-risk patients. The majority of respondents (67.7%) rated "technical problems" as the most important concern in case of AVD, followed by "increased mortality risk because of cardiovascular comorbidity" (29.8%). Pretransplant vascular interventions to facilitate transplantation were infrequently performed (71.4% mentioned <10 per year). Ninety (64.3%) respondents answered that an open vascular procedure should preferably be performed prior to kidney transplantation while 42 (30.0%) respondents preferred a simultaneous open vascular procedure. The decline rate was higher in the TASC D case compared to the TASC B case (26.9% and 9.7%, respectively). Respondents from centers with expertise in pretransplant vascular interventions were more likely to accept both patients with TASC D and B for transplantation. CONCLUSION: There is no uniformity in the screening, management, and acceptance of patients with AVD for transplantation. If a center declines a patient with AVD because of technical concerns, the patient should be referred for a second opinion to a tertiary center with expertise in pretransplant vascular interventions. Multidisciplinary meetings including a vascular surgeon and a cardiologist could help optimize these patients for transplantation.

Clinical outcome of kidney transplantation after bariatric surgery: A single-center, retrospective cohort study.

Patients with class II and III obesity and end-stage renal disease are often ineligible for kidney transplantation (KTx) due to increased postoperative complications and technically challenging surgery. Bariatric surgery (BS) can be an effective solution for KTx candidates who are considered inoperable. The aim of this study is to evaluate outcomes of KTx after BS and to compare the outcomes to obese recipients (BMI ≥ 35 kg/m2 ) without BS. This retrospective, single-center study included patients who received KTx after BS between January 1994 and December 2018. The primary outcome was postoperative complications. The secondary outcomes were graft and patient survival. In total, 156 patients were included, of whom 23 underwent BS prior to KTx. There were no significant differences in postoperative complications. After a median follow-up of 5.1 years, death-censored graft survival, uncensored graft survival, and patient survival were similar to controls (log rank test p = .845, .659, and .704, respectively). Dialysis pre-transplantation (Hazard Ratio (HR) 2.55; 95%CI 1.03-6.34, p = .043) and diabetes (HR 2.41; 95%CI 1.11-5.22, p = .027) were independent risk factors for all-cause mortality. A kidney from a deceased donor was an independent risk factor for death-censored graft loss (HR 1.98; 95%CI 1.04-3.79, p = .038). Patients who received a KTx after BS have similar outcomes as obese transplant recipients.

To screen or not to screen? The development of a prediction model for aorto-iliac stenosis in kidney transplant candidates.

Screening for aorto-iliac stenosis is important in kidney transplant candidates as its presence affects pre-transplantation decisions regarding side of implantation and the need for an additional vascular procedure. Reliable imaging techniques to identify this condition require contrast fluid, which can be harmful in these patients. To guide patient selection for these imaging techniques, we aimed to develop a prediction model for the presence of aorto-iliac stenosis. Patients with contrast-enhanced imaging available in the pre-transplant screening between January 1st, 2000 and December 31st, 2018 were included. A prediction model was developed using multivariable logistic regression analysis and internally validated using bootstrap resampling. Model performance was assessed with the concordance index and calibration slope. Three hundred and seventy-three patients were included, 90 patients (24.1%) had imaging-proven aorto-iliac stenosis. Our final model included age, smoking, peripheral arterial disease, coronary artery disease, a previous transplant, intermittent claudication and the presence of a femoral artery murmur. The model yielded excellent discrimination (optimism-corrected concordance index: 0.83) and calibration (optimism-corrected calibration slope: 0.91). In conclusion, this prediction model can guide the development of standardized protocols to decide which patients should receive vascular screening to identify aorto-iliac stenosis. External validation is needed before this model can be implemented in patient care.

A novel difficulty grading system for laparoscopic living donor nephrectomy.

BACKGROUND: Several difficulty grading systems have been developed as a useful tool for selecting patients and training surgeons in laparoscopic procedures. However, there is little information on predicting the difficulty of laparoscopic donor nephrectomy (LDN). The aim of this study was to develop a grading system to predict the difficulty of LDN. METHODS: Data of 1741 living donors, who underwent pure or hand-assisted LDN between 1994 and 2018 were analyzed. Multivariable analyses were performed to identify factors associated with prolonged operative time, defined as a difficulty index with 0 to 8. The difficulty of LDN was classified into three levels based on the difficulty index. RESULTS: Multivariable analyses identified that male (odds ratio [OR] 1.69, 95% CI 1.37-2.09, P < 0.001), BMI > 28 (OR 1.36, 95% CI 1.08-1.72, P = 0.009), pure LDN (OR 1.99, 95% CI 1.53-2.60, P < 0.001), multiple renal arteries (OR 2.38, 95% CI 1.83-3.10, P < 0.001) and multiple renal veins (OR 2.18, 95% CI 1.52-3.16, P < 0.001) were independent risk factors influencing prolonged operative time. The difficulty index based on these factors was calculated and categorized into three levels: low (0-2), intermediate (3-5), and high (6-8) difficulty. Operative time was significantly longer in the high difficulty group (225 min) than in the low (169 min, P < 0.001) and intermediate difficulty group (194 min, P < 0.001). The conversion rate was higher in the high difficulty group (4.4%) than in the low (2.1%, P = 0.04) and the intermediate difficulty group (3.0%, P = 0.27). No significant difference in major complications was found between the groups. CONCLUSION: We developed a novel grading system with simple preoperative donor factors to predict the difficulty of LDN. This grading system may help surgeons in patient selection to advance their experiences and/or teach fellows from simple to difficult LDN.

Optimizing porcine donor kidney preservation with normothermic or hypothermic machine perfusion: A systematic review.

We present an updated overview of the literature comparing normothermic with hypothermic machine perfusion in porcine kidneys. We conducted a systematic literature review in Embase, Medline Epub (Ovid), Cochrane Central, Web of Science, and Google Scholar on studies comparing normothermic (NMP) to hypothermic machine perfusion (HMP) in porcine kidneys. A meta-analysis was judged inappropriate because of heterogeneity in study design and perfusion methods. The quality of evidence of each included study was assessed. We included 8 studies. One out of 5 studies reported a significant difference in peak renal blood flow in favor of NMP. Oxygen consumption was significantly higher in NMP kidneys in 2 out of 5 studies. Peak creatinine clearance in NMP was significantly higher than that in HMP in 1 out of 6 studies. Two out of 4 studies reported a higher degree of epithelial vacuolation in kidneys receiving NMP over HMP. None of the studies found a significant difference between NMP and HMP in peak serum creatinine or graft survival after autotransplantation. The results need to be interpreted with caution in view of the diversity in perfusion protocols, the low quality of evidence, and the limited sample sizes.

Kidney Autotransplantation for Renal Artery Aneurysm: Case Series and a Systematic Review.

OBJECTIVES: Renal artery aneurysm (RAA) is a rare vascular disease. Kidney autotransplantation (KAT) is the treatment option when endovascular approach is not available. However, the evidence on KAT for RAA is mostly limited to small case series or reports. Here, we describe our 2 center experience of KAT for RAA, and provide the results of our systematic literature review to evaluate the outcomes. METHODS: A retrospective 2 center study was conducted in patients undergoing KAT for RAA between 2010 and 2018. Moreover, a systematic review was performed on medical databases to evaluate the outcomes of KAT for RAA. RESULTS: Nine patients were surgically treated at our institutions: eight with laparoscopic nephrectomy (LN), and 1 with open followed heterotopic KAT. All RAAs were ex-vivo reconstructed, and in 3 cases a vein graft was used for reconstruction. There were 2 postoperative major complications including 1 graft loss. In the systematic review, 102 studies with 355 patients were included. In 35 patients (9.9%) a minimal invasive approach was performed. The incidence of postoperative major complications and graft loss was 9.4% and 4.1%. CONCLUSIONS: Our experiences showed that laparoscopic approach for nephrectomy followed heterotopic KAT was feasible with good postoperative outcomes. KAT is an effective treatment for RAA when endovascular approach is not feasible for interpretation of the outcomes, the quality and sample size of the evidence should be taken into consideration.

The prognosis of kidney transplant recipients with aorto-iliac calcification: a systematic review and meta-analysis.

The prognosis of kidney transplant recipients (KTR) with vascular calcification (VC) in the aorto-iliac arteries is unclear. We performed a systematic review and meta-analysis to investigate their survival outcomes. Studies from January 1st, 2000 until March 5th, 2019 were included. Outcomes for meta-analysis were patient survival, (death-censored) graft survival and delayed graft function (DGF). Twenty-one studies were identified, eight provided data for meta-analysis. KTR with VC had a significantly increased mortality risk [1-year: risk ratio (RR) 2.19 (1.39-3.44), 5-year: RR 2.28 (1.86-2.79)]. The risk of 1-year graft loss was three times higher in recipients with VC [RR 3.15 (1.30-7.64)]. The risk of graft loss censored for death [1-year: RR 2.26 (0.58-2.73), 3-year: RR 2.19 (0.49-9.82)] and the risk of DGF (RR 1.24, 95% CI 0.98-1.58) were not statistically different. The quality of the evidence was rated as very low. To conclude, the presence of VC was associated with an increased mortality risk and risk of graft loss. In this small sample size, no statistical significant association between VC and DGF or risk of death-censored graft loss could be demonstrated. For interpretation of the outcomes, the quality and sample size of the evidence should be taken into consideration.

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.

Obese living kidney donors: a comparison of hand-assisted retroperitoneoscopic versus laparoscopic living donor nephrectomy.

BACKGROUND: The aim of this study was to examine the difference in outcome between hand-assisted retroperitoneoscopic and laparoscopic living donor nephrectomy in obese donors, and the impact of donor body mass index on outcome. METHODS: Out of 1108 living donors who underwent hand-assisted retroperitoneoscopic or laparoscopic donor nephrectomy between 2010 and 2018, 205 were identified having body mass index ≥ 30. These donors were included in this retrospective study, analyzing postoperative outcomes and remnant renal function. RESULTS: Out of 205 donors, 137 (66.8%) underwent hand-assisted retroperitoneoscopic donor nephrectomy and 68 donors (33.2%) underwent laparoscopic donor nephrectomy. Postoperative outcome did not show any significant differences between the hand-assisted retroperitoneoscopic donor nephrectomy group and the laparoscopic donor nephrectomy group in terms of major complications (2.2% vs. 1.5%, P = 0.72), postoperative pain scale (4 vs. 4, P = 0.67), and the length of stay (3 days vs. 3 days, P = 0.075). The results of kidney function in donors after nephrectomy demonstrated no significant differences between the groups. Additional analysis of 29 donors with body mass index ≥ 35 (14.1%) as compared with 176 donors with body mass index 30-35 (85.9%) revealed no significant differences between groups in postoperative outcomes as well as kidney function after donation. CONCLUSION: Our results show that laparoscopic living donor nephrectomy for obese donors is safe and feasible with good postoperative outcomes. There were no significant differences regarding postoperative outcome between hand-assisted retroperitoneoscopic and laparoscopic donor nephrectomy. Furthermore, the outcome in donors with body mass index ≥ 35 was comparable to donors with body mass index 30-35.