Project description:Use of deceased diabetic donor kidneys has increased over recent decades. However, scarce patient and allograft survival data are available taking into account recipient diabetes status. Here we performed a retrospective cohort study using data from the United Network of Organ Sharing in patients transplanted from 1994 to 2014. Multivariable Cox regression assessed recipient outcomes of 9074 diabetic vs. 152,555 non-diabetic donor kidneys. Recipients of diabetic donor kidneys had elevated rates of all-cause allograft failure (hazard ratio 1.21, 95% confidence interval 1.16-1.26) and death (1.19, 1.13-1.24) compared to recipients of kidneys from non-diabetic donors. Younger recipients of diabetic donor kidneys had worse allograft survival than older recipients of non-diabetic donor kidneys. There was significant interaction between donor and recipient diabetes status. To minimize the effect of unmeasured confounders, we used paired analyses of recipients of mate-kidneys from the same donor, with one diabetic recipient and the other non-diabetic. Among discordant recipient pairs of diabetic donor kidneys, diabetic recipients had significantly higher risk of allograft failure (1.27, 1.05-1.53) and death (1.53, 1.22-1.93) than non-diabetic recipients. After stratifying by Kidney Donor Profile Index risk category, diabetic recipients of diabetic donor kidneys continued to have worse allograft survival compared to all other patients. Thus, risks are associated with the use of diabetic donor kidneys. Understanding these risks will enable clinicians to better educate potential recipients.Kidney International advance online publication, 21 October 2015; doi:10.1038/ki.2015.325.
Project description:Two apolipoprotein L1 gene (APOL1) renal-risk variants in donors and African American (AA) recipient race are associated with worse allograft survival in deceased-donor kidney transplantation (DDKT) from AA donors. To detect other factors impacting allograft survival from deceased AA kidney donors, APOL1 renal-risk variants were genotyped in additional AA kidney donors.The APOL1 genotypes were linked to outcomes in 478 newly analyzed DDKTs in the Scientific Registry of Transplant Recipients. Multivariate analyses accounting for recipient age, sex, race, panel-reactive antibody level, HLA match, cold ischemia time, donor age, and expanded criteria donation were performed. These 478 transplantations and 675 DDKTs from a prior report were jointly analyzed.Fully adjusted analyses limited to the new 478 DDKTs replicated shorter renal allograft survival in recipients of APOL1 2-renal-risk-variant kidneys (hazard ratio [HR], 2.00; P = 0.03). Combined analysis of 1153 DDKTs from AA donors revealed donor APOL1 high-risk genotype (HR, 2.05; P = 3 × 10), older donor age (HR, 1.18; P = 0.05), and younger recipient age (HR, 0.70; P = 0.001) adversely impacted allograft survival. Although prolonged allograft survival was seen in many recipients of APOL1 2-renal-risk-variant kidneys, follow-up serum creatinine concentrations were higher than that in recipients of 0/1 APOL1 renal-risk-variant kidneys. A competing risk analysis revealed that APOL1 impacted renal allograft survival, but not recipient survival. Interactions between donor age and APOL1 genotype on renal allograft survival were nonsignificant.Shorter renal allograft survival is reproducibly observed after DDKT from APOL1 2-renal-risk-variant donors. Younger recipient age and older donor age have independent adverse effects on renal allograft survival.
Project description:MELODIC trial is an prospective, multicenter, non-randomized, open-label, parallel trial, aimed at assessing the efficacy (in terms of overall survival: OS) of liver transplantation (LT) in unresecable CRC liver-only metastases, compared with a matched cohort of patients bearing the same tumor characteristics, and treated with chemotherapy. Synthesis of Inclusion parameters: "10;10;10;100"
Project description:The COVID-19 pandemic brought living donor kidney transplant programs across the United States to a near halt in March 2020. As programs have begun to reopen, potential donor candidates often inquire about their risk of a COVID-19 infection and its potential impact on kidney function after donation. To address their concerns, we surveyed 1740 former live kidney donors at four transplant centers located in New York and Michigan. Of these, 839 (48.2%) donors responded, their mean age was 46 ± 12.5 years, 543 (65%) were females, and 611 (73%) were white. Ninety-two donors (11%) had symptoms suggestive of a COVID-19 infection with fever (48%) and fatigue (43%) being the most common. Among those with symptoms, 42 donors underwent testing and 16 tested positive. Testing was more common among donors with private insurance, and a positive test result was more common among young black donors. Only one donor surveyed required hospitalization and none required dialysis. Fourteen donors have recovered completely and two partially. Our survey highlights that a COVID-19 infection in former donors results in a mild disease with good recovery. These data will be useful for transplant programs to counsel living donors who are considering kidney donation during this pandemic.
Project description:BACKGROUND AND OBJECTIVES:The fraction of kidneys procured for transplant that are discarded is rising in the United States. Identifying donors from whom only one kidney was discarded allows us to control for donor traits and better assess reasons for organ discard. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS:We conducted a retrospective cohort study using United Network for Organ Sharing Standard Transplant Analysis and Research file data to identify deceased donors from whom two kidneys were procured and at least one was transplanted. Unilateral pairs were defined as kidney pairs from a single donor from whom one kidney was discarded ("unilateral discard") but the other was transplanted ("unilateral transplant"). Organ quality was estimated using the Kidney Donor Risk Index and Kidney Donor Profile Index (KDPI). We compared all-cause graft failure rates for unilateral transplants to those for bilateral transplant Kaplan-Meier methods, and life table methodology was used to evaluate 1-, 2-, 3-, and 5-year survival rates of transplants from bilateral and unilateral donors. RESULTS:Compared with bilateral donors (i.e., both kidneys transplanted) (n=80,584), unilateral donors (i.e., only one kidney transplanted) (n=7625) had higher mean terminal creatinine (1.3±2.1 mg/dl versus 1.1±0.9 mg/dl) and KDPI (67%±25% versus 42%±27%), were older, and were more likely to have hypertension, diabetes, hepatitis C, terminal stroke, or meet Centers for Disease Control and Prevention high-risk donor criteria. Unilateral discards were primarily attributed to factors expected to be similar in both kidneys from a donor: biopsy findings (22%), no interested recipient (13%), and donor history (7%). Anatomic abnormalities (14%), organ damage (11%), and extended ischemia (6%) accounted for about 30% of discards, but were the commonest reasons among low KDPI kidneys. Among kidneys with KDPI?60%, there was an incremental difference in allograft survival over time (for unilateral versus bilateral transplants, 1-year survival: 83% versus 87%; 3-year survival: 69% versus 73%; 5-year survival: 51% versus 58%). CONCLUSIONS:A large number of discarded kidneys were procured from donors whose contralateral kidneys were transplanted with good post-transplant outcomes.
Project description:In the article a virus transmission model is constructed on a simplified social network. The social network consists of more than 2 million nodes, each representing an inhabitant of Slovenia. The nodes are organised and interconnected according to the real household and elderly-care center distribution, while their connections outside these clusters are semi-randomly distributed and undirected. The virus spread model is coupled to the disease progression model. The ensemble approach with the perturbed transmission and disease parameters is used to quantify the ensemble spread, a proxy for the forecast uncertainty. The presented ongoing forecasts of COVID-19 epidemic in Slovenia are compared with the collected Slovenian data. Results show that at the end of the first epidemic wave, the infection was twice more likely to transmit within households/elderly care centers than outside them. We use an ensemble of simulations (N = 1000) and data assimilation approach to estimate the COVID-19 forecast uncertainty and to inversely obtain posterior distributions of model parameters. We found that in the uncontrolled epidemic, the intrinsic uncertainty mostly originates from the uncertainty of the virus biology, i.e. its reproduction number. In the controlled epidemic with low ratio of infected population, the randomness of the social network becomes the major source of forecast uncertainty, particularly for the short-range forecasts. Virus transmission models with accurate social network models are thus essential for improving epidemics forecasting.
Project description:Background and objectivesIn kidney transplantation, the relative contribution of donor versus other factors on clinical outcomes is unknown. We sought to quantify overall donor effects on transplant outcomes for kidney donations from deceased donors.Design, setting, participants, & measurementsFor paired donations from deceased donors resulting in transplants to different recipients, the magnitude of donor effects can be quantified by examining the excess of concordant outcomes within kidney pairs beyond chance concordance. Using data from the Organ Procurement and Transplantation Network between the years 2013 and 2017, we examined concordance measures for delayed graft function, death-censored 1-year graft failure, and death-censored 3-year graft failure. The concordance measures were excess relative risk, excess absolute risk, and the fixation index (where zero is no concordance and one is perfect concordance). We further examined concordance in strata of kidneys with similar values of the Kidney Donor Profile Index, a common metric of organ quality.ResultsIf the transplant of the kidney mate resulted in delayed graft function, risk for delayed graft function was 19% higher (95% confidence interval [95% CI], 18% to 20%), or 1.76-fold higher (95% CI, 1.73- to 1.80-fold), than baseline. If a kidney graft failed within 1 year, then the kidney mate's risk of failure was 6% higher (95% CI, 4% to 9%), or 2.85-fold higher (95% CI, 2.25- to 3.48-fold), than baseline. For 3-year graft failure, the excess absolute risk was 7% (95% CI, 4% to 10%) but excess relative risk was smaller, 1.91-fold (95% CI, 1.56- to 2.28-fold). Fixation indices were 0.25 for delayed graft function (95% CI, 0.24 to 0.27), 0.07 for 1-year graft failure (95% CI, 0.04 to 0.09), and 0.07 for 3-year graft failure (95% CI, 0.04 to 0.10). Results were similar in strata of kidneys with a similar Kidney Donor Profile Index.ConclusionsOverall results indicated that the donor constitution has small or moderate effect on post-transplant clinical outcomes.
Project description:COVID-19 pandemic dramatically impacted transplantation landscape. Scientific societies recommend against the use of donors with active SARS-CoV-2 infection. Italian Transplant Authority recommended to test recipients/donors for SARS-CoV-2-RNA immediately before liver transplant (LT) and, starting from November 2020, grafts from deceased donors with active SARS-CoV-2 infection were allowed to be considered for urgent-need transplant candidates with active/resolved COVID-19. We present the results of the first 10 LTs with active COVID-19 donors within an Italian multicenter series. Only two recipients had a positive molecular test at LT and one of them remained positive up to 21 days post-LT. None of the other eight recipients was found to be SARS-CoV-2 positive during follow-up. IgG against SARS-CoV-2 at LT were positive in 80% (8/10) of recipients, and 71% (5/7) showed neutralizing antibodies, expression of protective immunity related to recent COVID-19. In addition, testing for SARS-CoV-2 RNA on donors' liver biopsy at transplantation was negative in 100% (9/9), suggesting a very low risk of transmission with LT. Immunosuppression regimen remained unchanged, according to standard protocol. Despite the small number of cases, these data suggest that transplanting livers from donors with active COVID-19 in informed candidates with SARS-CoV-2 immunity, might contribute to safely increase the donor pool.
Project description:BackgroundDeceased-donor kidney transplantation (KT) from hepatitis C (HCV)-infected donors into HCV-uninfected recipients (HCV D+/R-) could become standard care in the near future. However, HCV viral replication by viral transmission might lead to a higher incidence of cytomegalovirus (CMV) infection in these recipients.MethodsA national-registry-based retrospective cohort study was conducted using the Scientific Registry of Transplant Recipients (SRTR) data set. We assessed the incidence of CMV infection in HCV antibody (Ab) negative recipients receiving kidneys from HCV Ab positive (HCVAb D+/R-) and negative (HCVAb D-/R-) donors. The risk of CMV infection was analyzed by Cox regression analysis in a propensity score (PS) matched-cohort of HCVAb D+/R- (n = 950) versus HCVAb D-/R- (n = 950). Sensitivity analysis was also conducted in the entire cohort (n = 181 082).ResultsThe mean age at baseline was 54 years, 75% were male, and 55% of the patients were African American in PS-matched cohort. Compared to the HCVAb D-/R - patients, recipients with HCVAb D+/R - showed identical probability for the incidence of CMV infection (Hazard Ratio (HR) = 1.00, 95% Confidence Interval (CI): 0.82-1.22). In the sensitivity analysis, compared to the HCVAb D-/R - patients, the HCVAb D+/R - group had a significantly lower risk of CMV infection in the unadjusted analysis (HR = 0.75, 95%CI: 0.65-0.85), while this risk difference disappeared after the adjusted analysis (HR = 0.99, 95%CI: 0.87-1.14).ConclusionThe incidence of CMV infection was similar in recipients who received HCVAb D + and HCVAb D - KT. Further studies are needed to assess this association in KT from HCV nucleic acid positive donors.