Single center utilization and post-transplant outcomes of thoracoabdominal normothermic regional perfusion deceased cardiac donor organs.

INTRODUCTION: Thoracoabdominal normothermic regional perfusion (TA-NRP) following cardiac death is an emerging multivisceral organ procurement technique. Recent national studies on outcomes of presumptive TA-NRP-procured organs are limited by potential misclassification since TA-NRP is not differentiated from donation after cardiac death (DCD) in registry data. METHODS: We studied 22 donors whose designees consented to TA-NRP and organ procurement performed at our institution between January 20, 2020 and July 3, 2022. We identified these donors in SRTR to describe organ utilization and recipient outcomes and compared them to recipients of traditional DCD (tDCD) and donation after brain death (DBD) organs during the same timeframe. RESULTS: All 22 donors progressed to cardiac arrest and underwent TA-NRP followed by heart, lung, kidney, and/or liver procurement. Median donor age was 41 years, 55% had anoxic brain injury, 45% were hypertensive, 0% were diabetic, and median kidney donor profile index was 40%. TA-NRP utilization was high across all organ types (88%-100%), with a higher percentage of kidneys procured via TA-NRP compared to tDCD (88% vs. 72%, p = .02). Recipient and graft survival ranged from 89% to 100% and were comparable to tDCD and DBD recipients (p ≥ .2). Delayed graft function was lower for kidneys procured from TA-NRP compared to tDCD donors (27% vs. 44%, p = .045). CONCLUSION: Procurement from TA-NRP donors yielded high organ utilization, with outcomes comparable to tDCD and DBD recipients across organ types. Further large-scale study of TA-NRP donors, facilitated by its capture in the national registry, will be critical to fully understand its impact as an organ procurement technique.

Wait Time Advantage for Transplant Candidates With HIV Who Accept Kidneys From Donors With HIV Under the HOPE Act.

BACKGROUND: Kidney transplant (KT) candidates with HIV face higher mortality on the waitlist compared with candidates without HIV. Because the HIV Organ Policy Equity (HOPE) Act has expanded the donor pool to allow donors with HIV (D + ), it is crucial to understand whether this has impacted transplant rates for this population. METHODS: Using a linkage between the HOPE in Action trial (NCT03500315) and Scientific Registry of Transplant Recipients, we identified 324 candidates listed for D + kidneys (HOPE) compared with 46 025 candidates not listed for D + kidneys (non-HOPE) at the same centers between April 26, 2018, and May 24, 2022. We characterized KT rate, KT type (D + , false-positive [FP; donor with false-positive HIV testing], D - [donor without HIV], living donor [LD]) and quantified the association between HOPE enrollment and KT rate using multivariable Cox regression with center-level clustering; HOPE was a time-varying exposure. RESULTS: HOPE candidates were more likely male individuals (79% versus 62%), Black (73% versus 35%), and publicly insured (71% versus 52%; P < 0.001). Within 4.5 y, 70% of HOPE candidates received a KT (41% D + , 34% D - , 20% FP, 4% LD) versus 43% of non-HOPE candidates (74% D - , 26% LD). Conversely, 22% of HOPE candidates versus 39% of non-HOPE candidates died or were removed from the waitlist. Median KT wait time was 10.3 mo for HOPE versus 60.8 mo for non-HOPE candidates ( P < 0.001). After adjustment, HOPE candidates had a 3.30-fold higher KT rate (adjusted hazard ratio = 3.30, 95% confidence interval, 2.14-5.10; P < 0.001). CONCLUSIONS: Listing for D + kidneys within HOPE trials was associated with a higher KT rate and shorter wait time, supporting the expansion of this practice for candidates with HIV.

Transplant Candidate Outcomes After Declining a DCD Liver in the United States.

BACKGROUND: In the context of the organ shortage, donation after circulatory death (DCD) provides an opportunity to expand the donor pool. Although deceased-donor liver transplantation from DCD donors has expanded, DCD livers continue to be discarded at elevated rates; the use of DCD livers from older donors, or donors with comorbidities, is controversial. METHODS: Using US registry data from 2009 to 2020, we identified 1564 candidates on whose behalf a DCD liver offer was accepted ("acceptors") and 16 981 candidates on whose behalf the same DCD offers were declined ("decliners"). We characterized outcomes of decliners using a competing risk framework and estimated the survival benefit (adjusted hazard ratio [95% confidence interval]) of accepting DCD livers using Cox regression. RESULTS: Within 10 y of DCD offer decline, 50.9% of candidates died or were removed from the waitlist before transplantation with any type of allograft. DCD acceptors had lower mortality compared with decliners at 10 y postoffer (35.4% versus 48.9%, P < 0.001). After adjustment for candidate covariates, DCD offer acceptance was associated with a 46% reduction in mortality (0.54 [0.49-0.61]). Acceptors of older (age ≥50), obese (body mass index ≥30), hypertensive, nonlocal, diabetic, and increased risk DCD livers had 44% (0.56 [0.42-0.73]), 40% (0.60 [0.49-0.74]), 48% (0.52 [0.41-0.66]), 46% (0.54 [0.45-0.65]), 32% (0.68 [0.43-1.05]), and 45% (0.55 [0.42-0.72]) lower mortality risk compared with DCD decliners, respectively. CONCLUSIONS: DCD offer acceptance is associated with considerable long-term survival benefits for liver transplant candidates, even with older DCD donors or donors with comorbidities. Increased recovery and utilization of DCD livers should be encouraged.

Characterizing the risk of human leukocyte antigen-incompatible living donor kidney transplantation in older recipients.

Older compatible living donor kidney transplant (CLDKT) recipients have higher mortality and death-censored graft failure (DCGF) compared to younger recipients. These risks may be amplified in older incompatible living donor kidney transplant (ILDKT) recipients who undergo desensitization and intense immunosuppression. In a 25-center cohort of ILDKT recipients transplanted between September 24, 1997, and December 15, 2016, we compared mortality, DCGF, delayed graft function (DGF), acute rejection (AR), and length of stay (LOS) between 234 older (age ≥60 years) and 1172 younger (age 18-59 years) recipients. To investigate whether the impact of age was different for ILDKT recipients compared to 17 542 CLDKT recipients, we used an interaction term to determine whether the relationship between posttransplant outcomes and transplant type (ILDKT vs CLDKT) was modified by age. Overall, older recipients had higher mortality (hazard ratio: 1.632.072.65, P < .001), lower DCGF (hazard ratio: 0.360.530.77, P = .001), and AR (odds ratio: 0.390.540.74, P < .001), and similar DGF (odds ratio: 0.461.032.33, P = .9) and LOS (incidence rate ratio: 0.880.981.10, P = 0.8) compared to younger recipients. The impact of age on mortality (interaction P = .052), DCGF (interaction P = .7), AR interaction P = .2), DGF (interaction P = .9), and LOS (interaction P = .5) were similar in ILDKT and CLDKT recipients. Age alone should not preclude eligibility for ILDKT.

Transplant Center Attitudes Toward Early Liver Transplant for Alcohol-associated Liver Disease.

Background: Many centers have removed 6-mo pretransplant alcohol abstinence requirements to provide early liver transplant (ELT) for individuals with severe alcohol-associated liver disease (ALD), but the practice remains controversial. Using data collected from a nationally distributed survey, this study examines the practices and attitudes of transplant centers in the United States regarding ELT. Methods: A 20-item survey designed to assess center practices and provider attitudes was distributed to 225 medical and surgical directors from 143 liver transplant centers via email. Results: Surveys were completed by 28.9% (n = 65) of directors and 39% (n = 56) of transplant centers. All responding centers reported evaluating patients for ELT. Circumstances for considering ELT included <6 mo of survival without a transplant (96.4%) and inability to participate in alcohol addiction therapy pretransplant (75%). Most (66%) directors indicated their center had established criteria for listing candidates with severe ALD for ELT. Regarding important factors for ELT candidate listing, 57.1% indicated patient survival, 37.5% indicated graft survival, and 55.4% indicated having a low risk of relapse. Only 12.7% of directors affirmed the statement, "Six months of pretransplant abstinence decreases the risk of relapse." Conclusions: More centers are providing ELT for severe ALD. Inability to participate in alcohol addiction therapy and <6 mo of survival are commonly reported circumstances for considering ELT. Continued investigation of posttransplant outcomes in patients receiving ELT is essential to establishing a national consensus for distributing this valuable resource.

Cancer Risk Following HLA-Incompatible Living Donor Kidney Transplantation.

Incompatible living donor kidney transplant recipients (ILDKTr) require desensitization to facilitate transplantation, and this substantial upfront immunosuppression may result in serious complications, including cancer. Methods: To characterize cancer risk in ILDKTr, we evaluated 858 ILDKTr and 12 239 compatible living donor kidney transplant recipients (CLDKTr) from a multicenter cohort with linkage to the US transplant registry and 33 cancer registries (1997-2016). Cancer incidence was compared using weighted Cox regression. Results: Among ILDKTr, the median follow-up time was 6.7 y (maximum 16.1 y) for invasive cancers (ascertained via cancer registry linkage) and 5.0 y (maximum 16.1 y) for basal and squamous cell carcinomas (ascertained via the transplant registry and censored for transplant center loss to follow-up). Invasive cancers occurred in 53 ILDKTr (6.2%) and 811 CLDKTr (6.6%; weighted hazard ratio [wHR] 1.01; 95% confidence interval [CI], 0.76-1.35). Basal and squamous cell carcinomas occurred in 41 ILDKTr (4.8%) and 737 CLDKTr (6.0%) (wHR 0.99; 95% CI, 0.69-1.40). Cancer risk did not vary according to donor-specific antibody strength, and in an exploratory analysis, was similar between CLDKTr and ILDKTr for most cancer types and according to cancer stage, except ILDKTr had a suggestively increased risk of colorectal cancer (wHR 3.27; 95% CI, 1.23-8.71); however, this elevation was not significant after correction for multiple comparisons. Conclusions: These findings indicate that the risk of cancer is not increased for ILDKTr compared with CLDKTr. The possible elevation in colorectal cancer risk is unexplained and might suggest a need for tailored screening or prevention.

Digital imaging software versus the "eyeball" method in quantifying steatosis in a liver biopsy.

Steatotic livers represent a potentially underutilized resource to increase the donor graft pool; however, 1 barrier to the increased utilization of such grafts is the heterogeneity in the definition and the measurement of macrovesicular steatosis (MaS). Digital imaging software (DIS) may better standardize definitions to study posttransplant outcomes. Using HALO, a DIS, we analyzed 63 liver biopsies, from 3 transplant centers, transplanted between 2016 and 2018, and compared macrovesicular steatosis percentage (%MaS) as estimated by transplant center, donor hospital, and DIS. We also quantified the relationship between DIS characteristics and posttransplant outcomes using log-linear regression for peak aspartate aminotransferase, peak alanine aminotransferase, and total bilirubin on postoperative day 7, as well as logistic regression for early allograft dysfunction. Transplant centers and donor hospitals overestimated %MaS compared with DIS, with better agreement at lower %MaS and less agreement for higher %MaS. No DIS analyzed liver biopsies were calculated to be >20% %MaS; however, 40% of liver biopsies read by transplant center pathologists were read to be >30%. Percent MaS read by HALO was positively associated with peak aspartate aminotransferase (regression coefficient= 1.04 1.08 1.12 , p <0.001), peak alanine aminotransferase (regression coefficient = 1.04 1.08 1.12 , p <0.001), and early allograft dysfunction (OR= 1.10 1.40 1.78 , p =0.006). There was no association between HALO %MaS and total bilirubin on postoperative day 7 (regression coefficient = 0.99 1.01 1.04 , p =0.3). DIS provides reproducible quantification of steatosis that could standardize MaS definitions and identify phenotypes associated with good clinical outcomes to increase the utilization of steatite livers.

Association between Abdominal CT Measurements of Body Composition before Deceased Donor Liver Transplant with Posttransplant Outcomes.

Background Pre-liver transplant (LT) sarcopenia is associated with poor survival. Methods exist for measuring body composition with use of CT scans; however, it is unclear which components best predict post-LT outcomes. Purpose To quantify the association between abdominal CT-based body composition measurements and post-LT mortality in a large North American cohort. Materials and Methods This was a retrospective cohort of adult first-time deceased-donor LT recipients from 2009 to 2018 who underwent pre-LT abdominal CT scans, including at the L3 vertebral level, at Johns Hopkins Hospital. Measurements included sarcopenia (skeletal muscle index [SMI] <50 in men and <39 in women), sarcopenic obesity, myosteatosis (skeletal muscle CT attenuation <41 mean HU for body mass index [BMI] <25 and <33 mean HU for BMI ≥25), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and VAT/SAT ratio. Covariates in the adjusted models were selected with use of least absolute shrinkage and selection operator regression with lambda chosen by means of 10-fold cross-validation. Cox proportional hazards models were used to quantify associations with post-LT mortality. Model discrimination was quantified using the Harrell C-statistic. Results A total of 454 recipients (median age, 57 years [IQR, 50-62 years]; 294 men) were evaluated. In the adjusted model, pre-LT sarcopenia was associated with a higher hazard ratio (HR) of post-LT mortality (HR, 1.6 [95% CI: 1.1, 2.4]; C-statistic, 0.64; P = .02). SMI was significantly negatively associated with survival after adjustment for covariates. There was no evidence that myosteatosis was associated with mortality (HR, 1.3 [95% CI: 0.86, 2.1]; C-statistic, 0.64; P = .21). There was no evidence that BMI (HR, 1.2 [95% CI: 0.95, 1.4]), VAT (HR, 1.0 [95% CI: 0.98, 1.1]), SAT (HR, 1.0 [95% CI: 0.97, 1.0]), and VAT/SAT ratio (HR, 1.1 [95% CI: 0.90, 1.4]) were associated with mortality (P = .15-.77). Conclusions Sarcopenia, as assessed on routine pre-liver transplant (LT) abdominal CT scans, was the only factor significantly associated with post-LT mortality. © RSNA, 2022 See also the editorial by Ruehm in this issue.

Telemedicine services for living kidney donation: A US survey of multidisciplinary providers.

Individuals considering living kidney donation face geographic, financial, and logistical challenges. Telemedicine can facilitate healthcare access/care coordination. Yet difficulties exist in telemedicine implementation and sustainability. We sought to examine centers' practices and providers' attitudes toward telemedicine to improve services for donors. We surveyed multidisciplinary providers from 194 active adult US living donor kidney transplant centers; 293 providers from 128 unique centers responded to the survey (center representation rate = 66.0%), reflecting 83.9% of practice by donor volume and 91.5% of US states/territories. Most centers (70.3%) plan to continue using telemedicine beyond the pandemic for donor evaluation/follow-up. Video was mostly used by nephrologists, surgeons, and psychiatrists/psychologists. Telephone and video were mostly used by social workers, while video or telephone was equally used by coordinators. Half of respondent nephrologists and surgeons were willing to accept a remote completion of physical exam; 68.3% of respondent psychiatrists/psychologists and social workers were willing to accept a remote completion of mental status exam. Providers strongly agreed that telemedicine was convenient for donors and would improve the likelihood of completing donor evaluation. However, providers (65.5%) perceived out-of-state licensing as a key policy/regulatory barrier. These findings help inform practice and underscore the instigation of policies to remove barriers using telemedicine to increase living kidney donation.

HOPE in action: A prospective multicenter pilot study of liver transplantation from donors with HIV to recipients with HIV.

Liver transplantation (LT) from donors-with-HIV to recipients-with-HIV (HIV D+/R+) is permitted under the HOPE Act. There are only three international single-case reports of HIV D+/R+ LT, each with limited follow-up. We performed a prospective multicenter pilot study comparing HIV D+/R+ to donors-without-HIV to recipients-with-HIV (HIV D-/R+) LT. We quantified patient survival, graft survival, rejection, serious adverse events (SAEs), human immunodeficiency virus (HIV) breakthrough, infections, and malignancies, using Cox and negative binomial regression with inverse probability of treatment weighting. Between March 2016-July 2019, there were 45 LTs (8 simultaneous liver-kidney) at 9 centers: 24 HIV D+/R+, 21 HIV D-/R+ (10 D- were false-positive). The median follow-up time was 23 months. Median recipient CD4 was 287 cells/µL with 100% on antiretroviral therapy; 56% were hepatitis C virus (HCV)-seropositive, 13% HCV-viremic. Weighted 1-year survival was 83.3% versus 100.0% in D+ versus D- groups (p = .04). There were no differences in one-year graft survival (96.0% vs. 100.0%), rejection (10.8% vs. 18.2%), HIV breakthrough (8% vs. 10%), or SAEs (all p > .05). HIV D+/R+ had more opportunistic infections, infectious hospitalizations, and cancer. In this multicenter pilot study of HIV D+/R+ LT, patient and graft survival were better than historical cohorts, however, a potential increase in infections and cancer merits further investigation.

National Landscape of Human Immunodeficiency Virus-Positive Deceased Organ Donors in the United States.

BACKGROUND: Organ transplantation from donors with human immunodeficiency virus (HIV) to recipients with HIV (HIV D+/R+) presents risks of donor-derived infections. Understanding clinical, immunologic, and virologic characteristics of HIV-positive donors is critical for safety. METHODS: We performed a prospective study of donors with HIV-positive and HIV false-positive (FP) test results within the HIV Organ Policy Equity (HOPE) Act in Action studies of HIV D+/R+ transplantation (ClinicalTrials.gov NCT02602262, NCT03500315, and NCT03734393). We compared clinical characteristics in HIV-positive versus FP donors. We measured CD4 T cells, HIV viral load (VL), drug resistance mutations (DRMs), coreceptor tropism, and serum antiretroviral therapy (ART) detection, using mass spectrometry in HIV-positive donors. RESULTS: Between March 2016 and March 2020, 92 donors (58 HIV positive, 34 FP), representing 98.9% of all US HOPE donors during this period, donated 177 organs (131 kidneys and 46 livers). Each year the number of donors increased. The prevalence of hepatitis B (16% vs 0%), syphilis (16% vs 0%), and cytomegalovirus (CMV; 91% vs 58%) was higher in HIV-positive versus FP donors; the prevalences of hepatitis C viremia were similar (2% vs 6%). Most HIV-positive donors (71%) had a known HIV diagnosis, of whom 90% were prescribed ART and 68% had a VL <400 copies/mL. The median CD4 T-cell count (interquartile range) was 194/µL (77-331/µL), and the median CD4 T-cell percentage was 27.0% (16.8%-36.1%). Major HIV DRMs were detected in 42%, including nonnucleoside reverse-transcriptase inhibitors (33%), integrase strand transfer inhibitors (4%), and multiclass (13%). Serum ART was detected in 46% and matched ART by history. CONCLUSION: The use of HIV-positive donor organs is increasing. HIV DRMs are common, yet resistance that would compromise integrase strand transfer inhibitor-based regimens is rare, which is reassuring regarding safety.

Temporal Trends in Utilization and Outcomes of DCD Livers in the United States.

BACKGROUND: Historically, donation after circulatory death (DCD) livers were frequently discarded because of higher mortality and graft loss after liver transplantation (LT). However, the demand for LT continues to outstrip the supply of "acceptable" organs. Additionally, changes in the donor pool, organ allocation, and clinical management of donors and recipients, and improved clinical protocols might have altered post-DCD-LT outcomes. METHODS: We studied 5975 recovered DCD livers using US Scientific Registry of Transplant Recipients data from 2005 to 2017, with a comparison group of 78 235 adult donation after brain death (DBD) livers recovered during the same time period. We quantified temporal trends in discard using adjusted multilevel logistic regression and temporal trends in post-LT mortality and graft loss for DCD LT recipients using adjusted Cox regression. RESULTS: DCD livers were more likely to be discarded than DBD livers across the entire study period, and the relative likelihood of discard increased over time (adjusted odds ratio [aOR] of discard DCD versus DBD 3.854.455.14 2005-2007, 5.225.876.59 2015-2017) despite improving outcomes after DCD LT. Mortality risk for DCD LTs decreased in each time period (compared with 2005-2007, aHR 2008-2011 0.720.840.97, aHR 2012-2014 0.480.580.70, aHR 2015-2017 0.340.430.55), as did risk of graft loss (compared with 2005-2007, aHR 2008-2011 0.690.810.94, aHR 2012-2014 0.450.550.67, aHR 2015-2017 0.360.450.56). CONCLUSIONS: Despite dramatic improvements in outcomes of DCD LT recipients, DCD livers remain substantially more likely to be discarded than DBD livers, and this discrepancy has actually increased over time. DCD livers are underutilized and have the potential to expand the donor pool.

Trends in Heart and Lung Transplantation in the United States Across the COVID-19 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic has had a variable course across the United States. Understanding its evolving impact on heart and lung transplantation (HT and LT) will help with planning for next phases of this pandemic as well as future ones. METHODS: We used Scientific Registry of Transplant Recipients data from before the pandemic to predict the number of waitlist registrations and transplants expected to occur between March 15, 2020, and December 31, 2020 (if no pandemic had occurred), and compared these expectations to observed rates. The observed era was divided into wave 1 (March 15-May 31), wave 2 (June 1-September 30), and wave 3 (October 1-December 31). We used multilevel Poisson regression to account for center- and state-level COVID-19 incidence. RESULTS: During wave 1, rates of heart registrations and transplants were 28% (incidence rate ratio [IRR]: 0.72 [95% confidence interval (CI), 0.67-0.77]) and 13% (IRR: 0.87 [95% CI, 0.80-0.93]) lower than expected; lung registrations and transplants were 40% (IRR: 0.60 [95% CI, 0.54-0.66]) and 28% (IRR: 0.72 [95% CI, 0.66-0.79]) lower. Decreases were greatest in states with the highest incidence where registrations were 53% (IRR: 0.47 [95% CI, 0.36-0.62]) and 59% (IRR: 0.41 [95% CI, 0.29-0.58]) and transplants were 57% (IRR: 0.43 [95% CI, 0.31-0.60]) and 58% (IRR: 0.42 [95% CI, 0.29-0.62]) lower than expected. Whereas HT largely recovered during waves 2 and 3, LT continued to fall short of expectations through the end of the year. CONCLUSIONS: The COVID-19 pandemic in the US substantially reduced thoracic transplant access. Ongoing evaluation of the risks and benefits of this dramatic practice change is critical to inform clinical decision-making moving forward.

Safety and Reactogenicity of 2 Doses of SARS-CoV-2 Vaccination in Solid Organ Transplant Recipients.

BACKGROUND: We studied the safety and reactogenicity SARS-CoV-2 mRNA vaccines in transplant recipients because immunosuppressed patients were excluded from vaccine trials. METHODS: US transplant recipients were recruited into this prospective cohort study through social media; those who completed the full vaccine series between December 9, 2020 and March 1, 2021 were included. We collected demographics, medical history, and safety information within 7 d after doses 1 and 2 (D1, D2). Associations between characteristics and reactions were evaluated using modified Poisson regression. RESULTS: We studied 741 transplant recipients who underwent BNT162b2 (54%) or mRNA-1273 (46%) vaccination. Median (interquartile range) age was 60 (44-69) y, 57% were female, and 10% were non-White. Although local site reactions decreased after D2 (85% D1 versus 78% D2, P < 0.001), systemic reactions increased (49% D1 versus 69% D2, P < 0.001). Younger participants were more likely to develop systemic symptoms after D1 (adjusted incidence rate ratio [aIRR] per 10 y = 0.850.900.94, P < 0.001) and D2 (aIRR per 10 y = 0.910.930.96, P < 0.001). Participants who experienced pain (aIRR = 1.111.662.47, P = 0.01) or redness (aIRR = 1.833.928.41, P < 0.01) were more likely to develop an antibody response to D1 of mRNA vaccines. No anaphylaxis, neurologic diagnoses, or SARS-CoV-2 diagnoses were reported. Infections were minimal (3% after D1, <0.01% after D2). One patient reported incident acute rejection post-D2. CONCLUSIONS: In solid organ transplant recipients undergoing mRNA vaccination, reactogenicity was similar to that reported in the original trials. Severe reactions were rare. These early safety data may help address vaccine hesitancy in transplant recipients.

MELD is MELD is MELD? Transplant center-level variation in waitlist mortality for candidates with the same biological MELD.

Recently, model for end-stage liver disease (MELD)-based liver allocation in the United States has been questioned based on concerns that waitlist mortality for a given biologic MELD (bMELD), calculated using laboratory values alone, might be higher at certain centers in certain locations across the country. Therefore, we aimed to quantify the center-level variation in bMELD-predicted mortality risk. Using Scientific Registry of Transplant Recipients (SRTR) data from January 2015 to December 2019, we modeled mortality risk in 33 260 adult, first-time waitlisted candidates from 120 centers using multilevel Poisson regression, adjusting for sex, and time-varying age and bMELD. We calculated a "MELD correction factor" using each center's random intercept and bMELD coefficient. A MELD correction factor of +1 means that center's candidates have a higher-than-average bMELD-predicted mortality risk equivalent to 1 bMELD point. We found that the "MELD correction factor" median (IQR) was 0.03 (-0.47, 0.52), indicating almost no center-level variation. The number of centers with "MELD correction factors" within ±0.5 points, and between ±0.5-± 1, ±1.0-±1.5, and ±1.5-±2.0 points was 62, 41, 13, and 4, respectively. No centers had waitlisted candidates with a higher-than-average bMELD-predicted mortality risk beyond ±2 bMELD points. Given that bMELD similarly predicts waitlist mortality at centers across the country, our results support continued MELD-based prioritization of waitlisted candidates irrespective of center.

Examination of Racial and Ethnic Differences in Deceased Organ Donation Ratio Over Time in the US.

Importance: Historically, deceased organ donation was lower among Black compared with White populations, motivating efforts to reduce racial disparities. The overarching effect of these efforts in Black and other racial/ethnic groups remains unclear. Objective: To examine changes in deceased organ donation over time. Design, Setting, and Participants: This population-based cohort study used data from January 1, 1999, through December 31, 2017, from the Scientific Registry of Transplant Recipients to quantify the number of actual deceased organ donors, and from the Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research Detailed Mortality File to quantify the number of potential donors (individuals who died under conditions consistent with organ donation). Data were analyzed from December 2, 2019, to May 14, 2020. Exposures: Race and ethnicity of deceased and potential donors. Main Outcomes and Measures: For each racial/ethnic group and year, a donation ratio was calculated as the number of actual deceased donors divided by the number of potential donors. Direct age and sex standardization was used to allow for group comparisons, and Poisson regression was used to quantify changes in donation ratio over time. Results: A total of 141 534 deceased donors and 5 268 200 potential donors were included in the analysis. Among Black individuals, the donation ratio increased 2.58-fold from 1999 to 2017 (yearly change in adjusted incidence rate ratio [aIRR], 1.05; 95% CI, 1.05-1.05; P < .001). This increase was significantly greater than the 1.60-fold increase seen in White individuals. Nevertheless, substantial racial differences remained, with Black individuals still donating at only 69% the rate of White individuals in 2017 (P < .001). Among other racial minority populations, changes were less drastic. Deceased organ donation increased 1.80-fold among American Indian/Alaska Native and 1.40-fold among Asian or Pacific Islander populations, with substantial racial differences remaining in 2017 (American Indian/Alaska Native population donation at 28% and Asian/Pacific Islander population donation at 85% the rate of the White population). Deceased organ donation differences between Hispanic/Latino and non-Hispanic/Latino populations increased over time (4% lower in 2017). Conclusions and Relevance: The findings of this cohort study suggest that differences in deceased organ donation between White and some racial minority populations have attenuated over time. The greatest gains were observed among Black individuals, who have been the primary targets of study and intervention. Despite improvements, substantial differences remain, suggesting that novel approaches are needed to understand and address relatively lower rates of deceased organ donation among all racial minorities.

Kidney Transplantation Confers Survival Benefit for Candidates With Pulmonary Hypertension.

Kidney transplantation (KT) is controversial in patients with pretransplant pulmonary hypertension (PtPH). We aimed to quantify post-KT graft and patient survival as well as survival benefit in recipients with PtPH. Methods: Using UR Renal Data System (2000-2018), we studied 90 819 adult KT recipients. Delayed graft function, death-censored graft failure, and mortality were compared between recipients with and without PtPH using inverse probability weighted logistic and Cox regression. Survival benefit of KT was determined using stochastic matching and stabilized inverse probability treatment Cox regression. Results: Among 90 819 KT recipients, 2641 (2.9%) had PtPH. PtPH was associated with higher risk of delayed graft function (odds ratio, 1.23; 95% CI, 1.10-1.36; P < 0.01), death-censored graft failure (hazard ratio [HR], 1.23; 95% CI, 1.11-1.38; P < 0.01), and mortality (HR, 1.56; 95% CI, 1.44-1.69; P < 0.01). However, patients with PtPH who received a KT had a 46% reduction in mortality (HR, 0.54; 95% CI, 0.48-0.61; P < 0.01) compared with those who remained on the waitlist. Conclusions: Although PtPH is associated with inferior post-KT outcomes, KT is associated with better survival compared with remaining on the waitlist. Therefore, KT is a viable treatment modality for appropriately selected patients with PtPH.

Characterizing the landscape and impact of infections following kidney transplantation.

Infections remain a major threat to successful kidney transplantation (KT). To characterize the landscape and impact of post-KT infections in the modern era, we used United States Renal Data System (USRDS) data linked to the Scientific Registry of Transplant Recipients (SRTR) to study 141 661 Medicare-primary kidney transplant recipients from January 1, 1999 to December 31, 2014. Infection diagnoses were ascertained by International Classification of Diseases, Ninth Revision (ICD-9) codes. The cumulative incidence of a post-KT infection was 36.9% at 3 months, 53.7% at 1 year, and 78.0% at 5 years. The most common infections were urinary tract infection (UTI; 46.8%) and pneumonia (28.2%). Five-year mortality for kidney transplant recipients who developed an infection was 24.9% vs 7.9% for those who did not, and 5-year death-censored graft failure (DCGF) was 20.6% vs 10.1% (P < .001). This translated to a 2.22-fold higher mortality risk (adjusted hazard ratio [aHR]: 2.15 2.222.29 , P < .001) and 1.92-fold higher DCGF risk (aHR: 1.84 1.911.98 , P < .001) for kidney transplant recipients who developed an infection, although the magnitude of this higher risk varied across infection types (for example, 3.11-fold higher mortality risk for sepsis vs 1.62-fold for a UTI). Post-KT infections are common and substantially impact mortality and DCGF, even in the modern era. Kidney transplant recipients at high risk for infections might benefit from enhanced surveillance or follow-up to mitigate these risks.