Effectiveness of Postoperative Single-shot and Continuous Transverse Abdominis Plane Block Compared to Conventional Analgesia in Hand-assisted Laparoscopic Live-donor Nephrectomy.

Background: Few studies have evaluated the efficacy of transverse abdominis plane (TAP) block in patients undergoing hand-assisted laparoscopic live-donor nephrectomy (HALN). We aimed to evaluate the analgesic effectiveness of TAP block as part of a multimodal pain management regimen in patients undergoing HALN. Methods: We retrospectively reviewed the medical records of living kidney donors at our center between June 2016 and February 2020. HALNs were performed via a transperitoneal approach through a suprapubic incision. Additional laparoscopic ports were used in the upper midabdomen. In consenting donors, TAP block was performed postoperatively under ultrasound guidance with either a single-shot or continuous infusion of long-acting local anesthetic (0.2%-0.5% ropivacaine). All the patients received postoperative around-the-clock ketorolac and acetaminophen. Results: Overall, 72 donors received the block (block group, 38 single-shot, 34 continuous), whereas 86 donors did not receive the block (control group). Baseline characteristics were comparable between the groups except for body weight (control: 71.8 ±â€…13.3 versus block: 77.8 ±â€…17.3 kg; P = 0.01) and intraoperative opioid dose (32.1 ±â€…9.6 versus 26.6 ±â€…10.7 morphine milligram equivalents; P < 0.001). After adjusting for baseline differences, postoperative opioid requirements were similar between the groups. When the baseline pain scale was adjusted for, there was no difference in the overall pain scale scores between the groups (P = 0.242). Subgroup analyses comparing single-shot or continuous TAP versus control did not show any differences. Conclusions: With the caveat of the retrospective nature of the study, the adjunctive effect of TAP block after transabdominal HALN was limited when other multimodal analgesia was used.

Prediction of High-Risk Donors for Kidney Discard and Nonrecovery Using Structured Donor Characteristics and Unstructured Donor Narratives.

Importance: Despite the unmet need, many deceased-donor kidneys are discarded or not recovered. Inefficient allocation and prolonged ischemia time are contributing factors, and early detection of high-risk donors may reduce organ loss. Objective: To evaluate the feasibility of machine learning (ML) and natural language processing (NLP) classification of donors with kidneys that are used vs not used for organ transplant. Design, Setting, and Participants: This retrospective cohort study used donor information (structured donor characteristics and unstructured donor narratives) from the United Network for Organ Sharing (UNOS). All donor offers to a single transplant center between January 2015 and December 2020 were used to train and validate ML models to predict donors who had at least 1 kidney transplanted (at our center or another center). The donor data from 2021 were used to test each model. Exposures: Donor information was provided by UNOS to the transplant centers with potential transplant candidates. Each center evaluated the donor and decided within an allotted time whether to accept the kidney for organ transplant. Main Outcomes and Measures: Outcome metrics of the test cohort included area under the receiver operating characteristic curve (AUROC), F1 score, accuracy, precision, and recall of each ML classifier. Feature importance and Shapley additive explanation (SHAP) summaries were assessed for model explainability. Results: The training/validation cohort included 9555 donors (median [IQR] age, 50 [36-58] years; 5571 male [58.3%]), and the test cohort included 2481 donors (median [IQR] age, 52 [40-59] years; 1496 male [60.3%]). Only 20% to 30% of potential donors had at least 1 kidney transplanted. The ML model with a single variable (Kidney Donor Profile Index) showed an AUROC of 0.69, F1 score of 0.42, and accuracy of 0.64. Multivariable ML models based on basic a priori structured donor data showed similar metrics (logistic regression: AUROC = 0.70; F1 score = 0.42; accuracy = 0.62; random forest classifier: AUROC = 0.69; F1 score = 0.42; accuracy = 0.64). The classic NLP model (bag-of-words model) showed its best metrics (AUROC = 0.60; F1 score = 0.35; accuracy = 0.59) by the logistic regression classifier. The advanced Bidirectional Encoder Representations From Transformers model showed comparable metrics (AUROC = 0.62; F1 score = 0.39; accuracy = 0.69) only after appending basic donor information. Feature importance and SHAP detected the variables (and words) that affected the models most. Conclusions and Relevance: Results of this cohort study suggest that models using ML can be applied to predict donors with high-risk kidneys not used for organ transplant, but the models still need further elaboration. The use of unstructured data is likely to expand the possibilities; further exploration of new approaches will be necessary to develop models with better predictive metrics.

A randomized controlled trial of preemptive rituximab to prevent recurrent focal segmental glomerulosclerosis post-kidney transplant (PRI-VENT FSGS): protocol and study design.

Background: Focal segmental glomerulosclerosis (FSGS) is a common cause of end-stage kidney disease requiring kidney transplantation and can recur in the allograft in 30-80% of recipients resulting in reduced graft survival. Plasmapheresis has shown efficacy in treating some cases of recurrent FSGS but isolated plasmapheresis has not demonstrated efficacy in preventing recurrent FSGS. Rituximab has had anecdotal success in preventing recurrence in a single center study but has not been studied in combination with plasmapheresis for preventing FSGS recurrence. Methods: We are conducting a randomized, controlled, multicenter clinical trial of adult and pediatric kidney transplant recipients with primary FSGS to assess whether plasmapheresis in combination with rituximab prevents recurrent disease post-transplantation. Discussion: Rituximab combined with plasmapheresis is a promising, novel therapy to prevent recurrent FSGS, a disease with limited therapeutic options and no consensus guidelines for prevention or treatment. Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT03763643, identifier NCT03763643.

A bio-instructive parylene-based conformal coating suppresses thrombosis and intimal hyperplasia of implantable vascular devices.

Implantable vascular devices are widely used in clinical treatments for various vascular diseases. However, current approved clinical implantable vascular devices generally have high failure rates primarily due to their surface lacking inherent functional endothelium. Here, inspired by the pathological mechanisms of vascular device failure and physiological functions of native endothelium, we developed a new generation of bioactive parylene (poly(p-xylylene))-based conformal coating to address these challenges of the vascular devices. This coating used a polyethylene glycol (PEG) linker to introduce an endothelial progenitor cell (EPC) specific binding ligand LXW7 (cGRGDdvc) onto the vascular devices for preventing platelet adhesion and selectively capturing endogenous EPCs. Also, we confirmed the long-term stability and function of this coating in human serum. Using two vascular disease-related large animal models, a porcine carotid artery interposition model and a porcine carotid artery-jugular vein arteriovenous graft model, we demonstrated that this coating enabled rapid generation of self-renewable "living" endothelium on the blood contacting surface of the expanded polytetrafluoroethylene (ePTFE) grafts after implantation. We expect this easy-to-apply conformal coating will present a promising avenue to engineer surface properties of "off-the-shelf" implantable vascular devices for long-lasting performance in the clinical settings.

Long-term Survival of Grafts From Small and Very Small Pediatric Donors in Women vs Men With End-stage Kidney Disease.

This cohort study compares graft survival of kidneys from small and very small pediatric donors in women vs men with end-stage kidney disease.

Benefit of B7-1 staining and abatacept for treatment-resistant post-transplant focal segmental glomerulosclerosis in a predominantly pediatric cohort: time for a reappraisal.

BACKGROUND: Primary FSGS manifests with nephrotic syndrome and may recur following KT. Failure to respond to conventional therapy after recurrence results in poor outcomes. Evaluation of podocyte B7-1 expression and treatment with abatacept (a B7-1 antagonist) has shown promise but remains controversial. METHODS: From 2012 to 2020, twelve patients developed post-KT FSGS with nephrotic range proteinuria, failed conventional therapy, and were treated with abatacept. Nine/twelve (< 21 years old) experienced recurrent FSGS; three adults developed de novo FSGS, occurring from immediately, up to 8 years after KT. KT biopsies were stained for B7-1. RESULTS: Nine KTRs (75%) responded to abatacept. Seven of nine KTRs were B7-1 positive and responded with improvement/resolution of proteinuria. Two patients with rFSGS without biopsies resolved proteinuria after abatacept. Pre-treatment UPCR was 27.0 ± 20.4 (median 13, range 8-56); follow-up UPCR was 0.8 ± 1.3 (median 0.2, range 0.07-3.9, p < 0.004). Two patients who were B7-1 negative on multiple KT biopsies did not respond to abatacept and lost graft function. One patient developed proteinuria while receiving belatacept, stained B7-1 positive, but did not respond to abatacept. CONCLUSIONS: Podocyte B7-1 staining in biopsies of KTRs with post-transplant FSGS identifies a subset of patients who may benefit from abatacept. A higher resolution version of the Graphical abstract is available as Supplementary information.

How to Deal With Kidney Retransplantation-Second, Third, Fourth, and Beyond.

Kidney transplantation is the best health option for patients with end-stage kidney disease. Ideally, a kidney transplant would last for the lifetime of each recipient. However, depending on the age of the recipient and details of the kidney transplant, there may be a need for a second, third, fourth, or even more kidney transplants. In this overview, the outcome of multiple kidney transplants for an individual is presented. Key issues include surgical approach and immunologic concerns. Included in the surgical approach is an analysis of transplant nephrectomy, with indications, timing, and immunologic impact. Allograft thrombosis, whether related to donor or recipient factors merits investigation to prevent it from happening again. Other posttransplant events such as rejection, viral illness (polyomavirus hominis type I), recurrent disease (focal segmental glomerulosclerosis), and posttransplant lymphoproliferative disease may lead to the need for retransplantation. The pediatric recipient is especially likely to need a subsequent kidney transplant. Finally, noncompliance/nonadherence can affect both adults and children. Innovative approaches may reduce the need for retransplantation in the future.

Automated En Masse Machine Learning Model Generation Shows Comparable Performance as Classic Regression Models for Predicting Delayed Graft Function in Renal Allografts.

BACKGROUND: Several groups have previously developed logistic regression models for predicting delayed graft function (DGF). In this study, we used an automated machine learning (ML) modeling pipeline to generate and optimize DGF prediction models en masse. METHODS: Deceased donor renal transplants at our institution from 2010 to 2018 were included. Input data consisted of 21 donor features from United Network for Organ Sharing. A training set composed of ~50%/50% split in DGF-positive and DGF-negative cases was used to generate 400 869 models. Each model was based on 1 of 7 ML algorithms (gradient boosting machine, k-nearest neighbor, logistic regression, neural network, naive Bayes, random forest, support vector machine) with various combinations of feature sets and hyperparameter values. Performance of each model was based on a separate secondary test dataset and assessed by common statistical metrics. RESULTS: The best performing models were based on neural network algorithms, with the highest area under the receiver operating characteristic curve of 0.7595. This model used 10 out of the original 21 donor features, including age, height, weight, ethnicity, serum creatinine, blood urea nitrogen, hypertension history, donation after cardiac death status, cause of death, and cold ischemia time. With the same donor data, the highest area under the receiver operating characteristic curve for logistic regression models was 0.7484, using all donor features. CONCLUSIONS: Our automated en masse ML modeling approach was able to rapidly generate ML models for DGF prediction. The performance of the ML models was comparable with classic logistic regression models.

Short- and Long-term Outcomes of Kidney Transplants From Very Small (≤15 kg) Pediatric Donors With Acute Kidney Injury.

BACKGROUND: Kidneys from small deceased pediatric donors with acute kidney injury (AKI) are commonly discarded owing to transplant centers' concerns regarding potentially inferior short- and long-term posttransplant outcomes. METHODS: We retrospectively analyzed our center's en bloc kidney transplants performed from November 2007 to January 2015 from donors ≤15 kg into adult recipients (≥18 y). We pair-matched grafts from 27 consecutive donors with AKI versus 27 without AKI for donor weight, donation after circulatory death status, and preservation time. RESULTS: For AKI versus non-AKI donors, median weight was 7.5 versus 7.1 kg; terminal creatinine was 1.7 (range, 1.1-3.3) versus 0.3 mg/dL (0.1-0.9). Early graft loss rate from thrombosis or primary nonfunction was 11% for both groups. Delayed graft function rate was higher for AKI (52%) versus non-AKI (15%) grafts (P = 0.004). Median estimated glomerular filtration rate was lower for AKI recipients only at 1 and 3 months (P < 0.03). Graft survival (death-censored) at 8 years was 78% for AKI versus 77% for non-AKI grafts. Late proteinuria rates for AKI versus non-AKI recipients with >4 years follow-up were not significantly different. CONCLUSIONS: Small pediatric donor AKI impacted early posttransplant kidney graft function, but did not increase risk for early graft loss and decreased long-term function. The presently high nonutilization rates for en bloc kidney grafts from very small pediatric donors with AKI appear therefore unjustified. Based on the outcomes of the present study, we infer that the reluctance to transplant single kidneys from larger pediatric donors with AKI lacks a rational basis as well. Our findings warrant further prospective study and confirmation in larger study cohorts.

Urologic complications after transplantation of 225 en bloc kidneys from small pediatric donors ≤20 kg: Incidence, management, and impact on graft survival.

Pediatric en bloc kidney transplants (EBKs) from small deceased pediatric donors are associated with increased early graft loss and morbidity. Yet, urologic complications post-EBK and their potential impact on graft survival have not been systematically studied. We retrospectively studied urological complications requiring intervention for 225 EBKs performed at our center January 2005 to September 2017 from donors ≤20 kg into recipients ≥18 years. Overall ureteral complication incidence after EBK was 9.8% (n = 22) (12% vs 2% for EBK donors < 10 vs ≥ 10 kg, respectively [P = .031]). The most common post-EBK urologic complication was a stricture (55%), followed by urine leak (41%). In all, 95% of all urologic complications occurred early within 5 months posttransplant (median, 138 days). Urologic complications could be successfully managed nonoperatively in 50% of all cases and had no impact on graft or patient survival. In summary, urologic complications after EBK were common, associated with lower donor weights, occurred early posttransplant, and were often amenable to nonoperative treatment, without adversely affecting survival. We conclude that the higher urologic complication rate after EBK (1) should not prevent increased utilization of small pediatric donor en bloc kidneys for properly selected recipients, and (2) warrants specific discussion with EBK recipients during the preoperative consent process.

Combined Ex Vivo Hypothermic and Normothermic Perfusion for Assessment of High-risk Deceased Donor Human Kidneys for Transplantation.

BACKGROUND: Despite careful clinical examination, procurement biopsy and assessment on hypothermic machine perfusion, a significant number of potentially useable deceased donor kidneys will be discarded because they are deemed unsuitable for transplantation. Ex vivo normothermic perfusion (EVNP) may be useful as a means to further assess high-risk kidneys to determine suitability for transplantation. METHODS: From June 2014 to October 2015, 7 kidneys (mean donor age, 54.3 years and Kidney Donor Profile Index, 79%) that were initially procured with the intention to transplant were discarded based on a combination of clinical findings, suboptimal biopsies, long cold ischemia time (CIT) and/or poor hypothermic perfusion parameters. They were subsequently placed on EVNP using oxygenated packed red blood cells and supplemental nutrition for a period of 3 hours. Continuous hemodynamic and functional parameters were assessed. RESULTS: After a mean CIT of 43.7 hours, all 7 kidneys appeared viable on EVNP with progressively increasing renal blood flow over the 3-hour period of perfusion. Five of the 7 kidneys had excellent macroscopic appearance, rapid increase in blood flow to 200 to 250 mL/min, urine output of 40 to 260 mL/h and increasing creatinine clearance. CONCLUSIONS: Favorable perfusion characteristics and immediate function after a 3-hour course of EVNP suggests that high-risk kidneys subjected to long CIT may have been considered for transplantation. The combined use of ex vivo hypothermic and normothermic perfusion may be a useful strategy to more adequately assess and preserve high-risk kidneys deemed unsuitable for transplantation. A clinical trial will be necessary to validate the usefulness of this approach.

Barriers to live and deceased kidney donation by patients with chronic neurological diseases: Implications for donor selection, donation timing, logistics, and regulatory compliance.

Live and deceased kidney donation by the numerous patients with advanced, progressive systemic neurological diseases, and other chronic neurological conditions (eg, high C-spine injury) remains largely unexplored. In a review of our current clinical practice, we identified multiple regulatory and clinical barriers. For live donation, mandatory reporting of postdonation donor deaths within 2 years constitutes a strong programmatic disincentive. We propose that the United Network for Organ Sharing should provide explicit regulatory guidance and reassurance for programs wishing to offer live donation to patients at higher risk of death during the reporting period. Under the proposal, live donor deaths within 30 days would still be regarded as donation-related, but later deaths would be related to the underlying disease. For deceased donation, donation after circulatory death (DCD) immediately following self-directed withdrawal of life-sustaining treatment ("conscious DCD") is not universally covered by existing DCD agreements with donor hospitals. Organ procurement organizations should thus systematically strive to revise these agreements. Obtaining adequate first-person consent from these communicatively severely impaired patients may be challenging. Optimized preservation and allocation protocols may maximize utilization of these DCD kidneys. Robust public debate and action by all stakeholders is necessary to lower existing barriers and maximize donation opportunities for patients with chronic neurological conditions.

Antibody-mediated rejection implies a poor prognosis in kidney transplantation: Results from a single center.

Two major barriers to achieving long-term graft survival include patient nonadherence in taking the prescribed immunosuppression and antibody-mediated rejection(AMR). We were therefore interested in determining the prognostic impact of developing an AMR component to rejection in a prospective randomized trial of 200 kidney transplant recipients who received dual induction therapy (rATG combined with either daclizumab or alemtuzumab) and planned early corticosteroid withdrawal. With a median follow-up of 96 months post-transplant, 40/200 developed a first BPAR; 9/200 developed a second BPAR. An AMR component to rejection was observed in 70% (28/40) of cases. Percentages having C4d deposition, histopathologic evidence of acute AMR, and presence of DSAs/non-DSAs at the time of first developing the AMR component were 64.3% (18/28), 60.7% (17/28), and 53.6% (15/28), respectively. Development of an AMR component was associated with a significantly higher death-censored graft failure rate following rejection in comparison with the patient state of experiencing BPAR but without developing an AMR component (estimated hazard ratio: 4.52, P = 0.01). The observed percentage developing graft failure following development of an AMR component was 53.6% (15/28) vs only 20.0%(3/15) if it was not observed. Actuarial death-censored graft survival at 60 months following development of an AMR component was 28.3 ± 11.9%. In summary, it appears that more effective AMR prevention/treatment strategies are warranted.

Impact of Willingness to Accept Hepatitis C Seropositive Kidneys Among Hepatitis C RNA-Positive Waitlisted Patients.

BACKGROUND: Kidney transplantation from hepatitis C seropositive (HCV+) donors may benefit hepatitis C RNA-positive (RNA+) candidates, but it is unclear how the willingness to be listed for and accept such kidneys affects waitlist and transplant outcomes. METHODS: In a single-center retrospective analysis, HCV+ transplant candidates (N = 169) listed from March 2004 to February 2015 were evaluated. All RNA+ candidates were offered the option to be listed for HCV+ donors. RNA- candidates were listed only for HCV- donors. RESULTS: Fifty-seven patients (51% of all RNA+ transplant candidates) willing to accept HCV+ donors were listed for both HCV+ and HCV- donor kidneys. During 6-year follow up, 43 (75%) of 57 patients accepting HCV+ versus 19 (35%) of 55 patients not accepting HCV+ received a deceased donor kidney transplant (P < 0.0001). Multivariable analysis demonstrated that willingness to be listed for and accept HCV+ kidneys was associated with receiving deceased donor kidney transplant (P = 0.0016). Fewer patients accepting HCV+ donors (7 [12%] vs 16 [29%]) were removed from the list due to death or deteriorated medical condition (P = 0.0117). Posttransplant patient and graft survival rates were not significantly different. Overall patient survival since the listing (combined waitlist and posttransplant survival) was similar among the groups. CONCLUSIONS: HCV RNA+ candidates had better access to transplantation and similar overall survival before the era of widespread use of direct-acting anti-HCV agents.

Predonation Volume of Future Remnant Cortical Kidney Helps Predict Postdonation Renal Function in Live Kidney Donors.

Purpose To determine whether the predonation computed tomography (CT)-based volume of the future remnant kidney is predictive of postdonation renal function in living kidney donors. Materials and Methods This institutional review board-approved, retrospective, HIPAA-compliant study included 126 live kidney donors who had undergone predonation renal CT between January 2007 and December 2014 as well as 2-year postdonation measurement of estimated glomerular filtration rate (eGFR). The whole kidney volume and cortical volume of the future remnant kidney were measured and standardized for body surface area (BSA). Bivariate linear associations between the ratios of whole kidney volume to BSA and cortical volume to BSA were obtained. A linear regression model for 2-year postdonation eGFR that incorporated donor age, sex, and either whole kidney volume-to-BSA ratio or cortical volume-to-BSA ratio was created, and the coefficient of determination (R2) for the model was calculated. Factors not statistically additive in assessing 2-year eGFR were removed by using backward elimination, and the coefficient of determination for this parsimonious model was calculated. Results Correlation was slightly better for cortical volume-to-BSA ratio than for whole kidney volume-to-BSA ratio (r = 0.48 vs r = 0.44, respectively). The linear regression model incorporating all donor factors had an R2 of 0.66. The only factors that were significantly additive to the equation were cortical volume-to-BSA ratio and predonation eGFR (P = .01 and P < .01, respectively), and the final parsimonious linear regression model incorporating these two variables explained almost the same amount of variance (R2 = 0.65) as did the full model. Conclusion The cortical volume of the future remnant kidney helped predict postdonation eGFR at 2 years. The cortical volume-to-BSA ratio should thus be considered for addition as an important variable to living kidney donor evaluation and selection guidelines. © RSNA, 2018.

Roux-en-Y gastric bypass is an effective bridge to kidney transplantation: Results from a single center.

Body mass index (BMI) > 35-40 kg/m2 is often a contraindication, while Roux-en-Y gastric bypass (RYGB) is performed to enable kidney transplantation. This single-center retrospective study evaluated pre- and post-transplant outcomes of 31 morbidly obese patients with end-stage renal disease having RYGB before kidney transplantation between July 2009 and June 2014. Fourteen RYGB patients were subsequently transplanted. Nineteen recipients not having GB with a BMI ≥ 36 kg/m2 at transplantation were used as historical controls. Mean BMI (±SE) before RYGB was 43.5 ± 0.7 kg/m2 (range: 35.4-50.5 kg/m2 ); 87.1% (27/31) achieved a BMI < 35 kg/m2 . The percentage having improved diabetes/hypertension control was 29.0% (9/31); 25.8% (8/31) had complications (mostly minor) after RYGB. Among transplanted patients, blacks/Hispanics comprised 78.6% (11/14) and 84.2% (16/19) of RYGB and controls; 57.1% (8/14) and 63.2% (12/19) had a (mostly long-standing) pretransplant history of diabetes. While biopsy-proven acute rejection (BPAR) occurred significantly higher among RYGB vs control patients (6/14 vs 3/19, P = .03), patients developing T-cell BPAR were also significantly more likely to have a tacrolimus (TAC) trough level < 4.0 ng/mL within 3 weeks of T-cell BPAR (P = .0007). In Cox's model, the impact of having a TAC level < 4.0 ng/mg remained significant (P = .007) while the effect of RYGB was no longer significant (P = .13). Infections, graft, and patient survival were not significantly different. Despite obvious effectiveness in achieving weight loss, RYGB will need more careful post-transplant monitoring given the observed higher BPAR rate.

Randomized trial of rATg/Daclizumab vs. rATg/Alemtuzumab as dual induction therapy in renal transplantation: Results at 8years of follow-up.

Our goal in using dual induction therapy is to bring the kidney transplant recipient closer (through more effectively timed lymphodepletion) to an optimally immunosuppressed state. Here, we report long-term results of a prospective randomized trial comparing (Group I,N=100) rATG/Dac (3 rATG, 2 Dac doses) vs. (Group II,N=100) rATG/Alemtuzumab(C1H) (1 dose each), using reduced tacrolimus dosing, EC-MPS, and early corticosteroid withdrawal. Lower EC-MPS dosing was targeted in Group II to avoid severe leukopenia. Median follow-up was 96mo post-transplant. There were no differences in 1st BPAR (including borderline) rates: 10/100 vs. 9/100 in Groups I and II during the first 12mo(P=0.54), and 20/100 vs. 20/100 throughout the study(P=0.90). Equally favorable renal function was maintained in both treatment arms(N.S.). While not significant, more patients in Group II experienced graft loss, 25/100 vs. 18/100 in Group I(P=0.23). Actuarial patient/graft survival at 96mo was 92%/83% vs. 85%/73% in Groups I and II(N.S.). DWFG-due-to-infection(N.S.), EC-MPS withholding-due-to-leukopenia during the first 2mo(P=0.03), and incidence of viral infections(P=0.09) were higher in Group II, whereas EC-MPS withholding-due-to-GI symptoms was higher in Group I(P=0.009). No other adverse event differences were observed. While long-term anti-rejection and renal function efficacy were demonstrated in both treatment arms, slight over-immunosuppression of Group II patients occurred.

Negative impact of prolonged cold storage time before machine perfusion preservation in donation after circulatory death kidney transplantation.

Kidney grafts are often preserved initially in static cold storage (CS) and subsequently on hypothermic machine perfusion (MP). However, the impact of CS/MP time on transplant outcome remains unclear. We evaluated the effect of prolonged CS/MP time in a single-center retrospective cohort of 59 donation after circulatory death (DCD) and 177 matched donation after brain death (DBD) kidney-alone transplant recipients. With mean overall CS/MP times of 6.0 h/30.0 h, overall incidence of delayed graft function (DGF) was higher in DCD transplants (30.5%) than DBD transplants (7.3%, P < 0.0001). In logistic regression, DCD recipient (P < 0.0001), longer CS time (P = 0.0002), male recipient (P = 0.02), and longer MP time (P = 0.08) were associated with higher DGF incidence. In evaluating the joint effects of donor type (DBD vs. DCD), CS time (<6 vs. ≥6 h), and MP time (<36 vs. ≥36 h) on DGF incidence, one clearly sees an unfavorable effect of MP time ≥36 h (P = 0.003) across each donor type and CS time stratum, whereas the unfavorable effect of CS time ≥6 h (P = 0.01) is primarily seen among DCD recipients. Prolonged cold ischemia time had no unfavorable effect on renal function or graft survival at 12mo post-transplant. Long CS/MP time detrimentally affects early DCD/DBD kidney transplant outcome when grafts were mainly preserved by MP; prolonged CS time before MP has a particularly negative impact in DCD kidney transplantation.