Morphologic and immunophenotypic evaluation of liver allograft biopsies with contemporaneous serum DSA measurements.

BACKGROUND: Acute antibody mediated rejection is increasingly identified in liver allografts as a unique form of alloimmune injury associated with donor specific antibodies (DSA). This manifests pathologically as microvascular injury and C4d uptake. Despite the liver allograft's relative resistance to alloimmune injury, liver allografts are not impervious to cellular and antibody-mediated rejection. METHODS: In this blinded control study, we evaluated CD163 immunohistochemistry and applied the Banff 2016 criteria for diagnosis of acute AMR on a group of indication allograft liver biopsies from DSA positive patients and compared them to indication biopsies from DSA negative controls. RESULTS: Most DSA positive patients were females (75%, p = .027), and underwent transplantation for HCV infection. Significant histopathological predictors of serum DSA positivity were Banff H-score (p = .01), moderate to severe cholestasis (p = .03), and CD163 score > 2 (p = .029). Other morphologic features that showed a trend with DSA positivity include Banff portal C4d-score (p = .06), bile ductular reaction (p = .07), and central perivenulitis (p = .07). The odds of DSA sMFI ≥5000 was 12.5 times higher in those with a C4d score >1 than those with a C4d score ≤ 1 (p = .04). Incidence of definite for aAMR in the DSA positive cohort was 25% (n = 5), and 0% in the DSA negative cohort. A group of 5 DSA positive cases were not classifiable by the current scheme. CONCLUSION: Sinusoidal CD163, Banff H-score, and diffuse C4d are predictors of serum DSA, and facilitate recognition of histopathological features associated with serum DSA and tissue-antibody interaction.

Back Table Preparation of the Right Lobe Live Donor Liver Allograft: A Crucial Part of the Adult Live Donor Liver Transplant Procedure.

INTRODUCTION: We aimed to describe our procedure for vascular reconstruction and back table bench preparation for the right lobe live donor allograft. Live donor liver transplantation (LDLT) remains an important option for the expansion of the donor pool. The procedure has been widely used, and its success is dependent on a technically perfect operation with appropriate inflow and outflow of the allograft. Adequate preparation of the right lobe (RL) allograft prior to implantation remains a vital part of the procedure. METHODS: Our technique of back table vascular reconstruction of the RL allograft has been performed using a hepatic vein patch venoplasty, inferior hepatic vein inclusion, portal vein reconstruction, and segment V and VIII reconstruction for all of our LDLTs. RESULTS: Between March 2009 and January 2020, 321 consecutive adult LDLTs were performed and underwent back table reconstruction with the techniques described. During that time period, no patients had hepatic insufficiency. There was a single thrombosis of a superior mesenteric vein (SMV) to PV jump conduit. CONCLUSIONS: Our technique of back table reconstruction of the LDLT right lobe graft remains a crucial part of the operative procedure. Our experience with RL grafts without middle hepatic vein (MHV) and our systematic approach for inflow and outflow reconstruction has yielded excellent results with no technical outflow issues and minimal inflow complications.

The combination of exposure to Tacrolimus, mycophenolic acid, Inosine 5'-Monophosphate Dehydrogenase activity and inhibition in the first week define early histological outcomes in renal transplant recipients.

Therapeutic drug monitoring is routine for Tacrolimus, while levels are not routinely monitored for mycophenolic acid (MPA). This study investigated the effect of early post-transplant pharmacokinetics (PK) of MPA and Tacrolimus along with the pharmacodynamics (PD) of MPA on biopsy-proven acute rejection (BPAR) after renal transplantation. A prospective PK/PD study with limited sampling (three blood samples) was conducted in renal transplant recipients on week 1, around Day 6 (n = 42) and at the 3rd-month biopsy on Day 90 (n = 23). The partial exposures (area under curve [AUC]0-3.5 h ) of both MPA and Tacrolimus obtained during the first week were more predictive of rejection (combined clinical and subclinical rejection) by Day 90 than their trough concentrations or Day 90 exposures. Patients with rejection had significantly worse renal function (eGFR) and a comparatively lower exposure to MPA during the first post-transplant week. The lower MPA exposure was also associated with sub-optimal inosine monophosphate dehydrogenase (IMPDH) inhibition in patients with rejection, and the probability of rejection was higher in the presence of an increased pre-transplant IMPDH activity. A composite of parameters, including MPA exposure and IMPDH activity was found to predict acute rejection and may be beneficial along with tacrolimus monitoring early after renal transplantation.

Function and longevity of renal grafts from high-KDPI donors.

BACKGROUND: High kidney-donor profile index (KDPI) kidneys have a shorter survival than grafts with lower KDPI values. It is still unclear, however, whether their shorter longevity depends on an inferior baseline function, faster functional decline, or the combination of both. METHODS: We analyzed the estimated glomerular filtration rate (eGFR) of 605 consecutive recipients of deceased donor kidney transplants (KT) at 1, 3, 6, 12, 18, 24, 36, 48, and 60 months. Comparisons were performed among four groups based on KDPI quartile: Group I-KDPI ≤ 25% (n = 151), Group II-KDPI 26-50% (n = 182), Group III-KDPI 51-75% (n = 176), and Group IV-KDPI 〉 75% (n = 96). Linear mixed model analysis was subsequently used to assess whether KDPI was independently associated with the decline in eGFR during the first 5-years after KT. We also analyzed the incidence of delayed graft function (DGF), rejection within the first year after KT, patient survival, graft survival, and death censored graft survival based on KDPI group. FINDINGS: High-KDPI grafts had lower eGFR immediately after KT, had a higher incidence of DGF and rejection. However, there were no signifcant differences in the adjusted rate (slope) of decline in eGFR among the four KDPI groups (P = .06). Although patient survival was signigicantly lower for recipients of high-KDPI grafts, death-censored graft survival was similar among the four KDPI groups (P = .33). CONCLUSIONS: The shorter functional survival of high-KDPI grafts seems to be due to their lower baseline eGFR rather than a more rapid functional decline after KT.

The Clinical Impact of Anti-HLA Donor Specific Antibody Detection Through First Year Screening on Stable Kidney Transplant Recipients.

Anti-HLA Donor Specific Antibody (DSA) detection post kidney transplant has been associated with adverse outcomes, though the impact of early DSA screening on stable patients remain unclear. We analyzed impact of DSA detection through screening in 1st year stable patients (n = 736) on subsequent estimated glomerular filtration rate (eGFR), death censored graft survival (DCGS), and graft failure (graft loss including return to dialysis or re-transplant, patient death, or eGFR < 20 ml/min at last follow up). Patients were grouped using 1st year screening into DSA+ (Class I, II; n = 131) or DSA- (n = 605). DSA+ group were more DR mismatched (p = 0.02), more sensitized (cPRA ≥90%, p = 0.002), less Caucasian (p = 0.04), and had less pre-emptive (p = 0.04) and more deceased donor transplants (p = 0.03). DSA+ patients had similar eGFR (54.8 vs. 53.8 ml/min/1.73 m2, p = 0.56), DCGS (91% vs. 94%, p = 0.30), and graft failure free survival (76% vs. 82%, p = 0.11). DSA timing and type did not impact survival. Among those with a protocol biopsy (n = 515), DSA detected on 1st year screening was a predictor for graft failure on multivariate analysis (1.91, 95% CI 1.03-3.55, p = 0.04). Overall, early DSA detection in stable patients was an independent risk factor for graft failure, though only among those who underwent a protocol biopsy.

Trends and impact on cold ischemia time and clinical outcomes using virtual crossmatch for deceased donor kidney transplantation in the United States.

For assessing human leukocyte antigen compatibility in deceased donor kidney transplantation, virtual crossmatch is used as an alternative to physical crossmatch and has potential to reduce cold ischemia time. The 2014 United States kidney allocation system prioritized highly sensitized candidates but led to increased shipping of kidneys. Using data from the Scientific Registry of Transplant Recipients, we evaluated changes in virtual crossmatch use with the new allocation policy and the impact of virtual crossmatch use on cold ischemia time and transplant outcomes. This was a retrospective cohort study of adult deceased donor kidney recipients in the United States (2011-2018) transplanted with either 9,632 virtual or 71,839 physical crossmatches. Before allocation change, only 9% of transplants were performed relying on a virtual crossmatch. After the 2014 allocation change, this increased by 2.4%/year so that 18% transplants in 2018 were performed with just a virtual crossmatch. There was significant variation in virtual crossmatch use among transplant regions (range 0.7-36%) and higher use was noted among large volume centers. Compared to physical crossmatches, virtual crossmatches were significantly associated with shorter cold ischemia times (mean 15.0 vs 16.5 hours) and similar death-censored graft loss and mortality (both hazard ratios HR 0.99) at a median follow-up of 2.9 years. Thus, our results show that virtual crossmatch is an attractive strategy for shortening cold ischemia time without negatively impacting transplant outcomes. Hence, strategies to optimize use and reduce practice variation may allow for maximizing benefits from virtual crossmatch.

Bimonthly viral monitoring for late-onset cytomegalovirus infection in kidney transplant recipients.

Kidney transplant recipients with high-risk cytomegalovirus (CMV) serostatus (seropositive donor to seronegative recipient) are at risk for late-onset CMV after cessation of antiviral prophylaxis. We report findings from a strategy of bimonthly (every 2 weeks) CMV screening for late-onset CMV. This is a single-center retrospective cohort study of 70 high-risk CMV kidney transplant recipients transplanted between June 2016 and September 2018. Patients were monitored at 6-12 months post-transplantation for late-onset CMV using bimonthly CMV nucleic acid testing (NAT). Adherence to screening and its correlation with CMV-related hospitalizations were assessed. Failure to prevent CMV-related hospitalization was classified into three categories (non-adherence to CMV testing, rapid CMV progression, and health system failure). Twenty-one (30%) patients developed CMV DNAemia, of whom 10 (14%) required hospitalization. Reasons for CMV-related hospitalization despite screening were (i) screening non-adherence (50%), (ii) rapid progression (40%), and (iii) health system failure (10%). Adherence to screening was associated with lower viral counts at diagnosis (r = -.44, p = .049) and a trend towards lower risk of CMV-related hospitalization (OR: 0.97 per 1% increase in adherence; 95% CI: 0.94-1.00; p = .06). Bimonthly monitoring for late-onset CMV allows for early CMV detection and may lower CMV-related hospitalization.

Donation after circulatory death is associated with increased fibrosis on 1-year post-transplant kidney allograft surveillance biopsy.

AIM: The use of kidneys donated after circulatory death (DCD) provides an invaluable expansion of the organ supply for transplantation. Here, we investigated the effect of DCD on fibrotic changes on 1 1-year post 1-transplant surveillance kidney allograft biopsy. METHODS: Recipients of a deceased donor kidney transplant between 2013 and 2017 at a single institution, who survived 1 year and underwent surveillance biopsy, were included in the analysis (n = 333: 87 DCD kidneys, 246 kidneys donated after brain death [DBD]). Banff scores for interstitial fibrosis and tubular atrophy were summed as IFTA and compared between the groups. RESULTS: DCD and DBD groups were comparable for baseline characteristics. Delayed graft function was 39% in DCD versus 19% in DBD, P = .0002. Patient and graft survival were comparable for DCD and DBD cohorts. IFTA scores were higher in DCD compared to DBD (2.43±..13 vs. 2.01±..08, P = .0054). On multivariate analysis, the odds of IFTA > 2 in the DCD group was 2.5× higher (95%CI: 1.354.63) than in the DBD group. Within the DCD group, kidneys with IFTA > 2 had inferior 5-year graft survival (P = .037). CONCLUSION: Compared to DBD kidneys, DCD kidneys developed a greater degree of fibrotic changes on 1-year post-transplant surveillance biopsy, which affected graft longevity within the DCD cohort.

Magnetic resonance imaging-derived proton density fat fraction (MRI-PDFF) is a viable alternative to liver biopsy for steatosis quantification in living liver donor transplantation.

This study aimed to investigate whether magnetic resonance imaging-derived proton density fat fraction (MRI-PDFF) can be a viable noninvasive alternative to liver biopsy for the quantification of living liver donor steatosis. Hepatic steatosis for 143 donors was graded by MRI-PDFF. Study endpoints included liver volume regeneration in donors, recipient outcomes including length of hospital stay, deaths, primary non-function (PNF), early allograft dysfunction (EAD), and small for size syndrome (SFSS). Correlation between MRI-PDFF determined donor steatosis and endpoints were analyzed. Donors had lower steatosis grade than non-donors. Donor remnant liver regenerated to an average of 82% of pre-donation volume by 101 ± 24 days with no complications. There was no correlation between percent liver regeneration and steatosis severity. Among recipients, 4 underwent redo-transplantation and 6 died, with no association with degree of steatosis. 52 recipients (36%) fulfilled criteria for EAD (driven by INR), with no difference in hepatic steatosis between groups. MRI-PDFF reliably predicted donor outcomes. Living donors with no or mild steatosis based on MRI-PDFF (ie, <20%) and meeting other criteria for donation can expect favorable post-surgical outcomes, including liver regeneration. Recipients had a low rate of death or retransplantation with no association between mild hepatic steatosis and EAD.

The liver transplant risk score prognosticates the outcomes of liver transplant recipients at listing.

BACKGROUND: We assessed if the risk of post-liver transplant mortality within 24 h could be stratified at the time of listing using the liver transplant risk score (LTRS). Secondary aims were to assess if the LTRS could stratify the risk of 30-day, 1-year mortality, and survival beyond the first year. METHODS: MELD, BMI, age, diabetes, and the need for dialysis were the five variables used to calculate the LTRS during patients' evaluation for liver transplantation. Mortality rates at 24 h, 30 days, and 1-year were compared among groups of patients with different LTRS. Patients with ABO-incompatibility, redo, multivisceral, partial graft and malignancies except for hepatocellular carcinoma were excluded. Data of 48,616 adult liver transplant recipients were extracted from the Scientific Registry of Transplant Recipients between 2002 and 2017. RESULTS: 24-h mortality was 0.9%, 1.0%, 1.1%, 1.7%, 2.3%, 2.0% and 3.5% for patients with LTRS of 0,1,2,3,4, 5 and ≥ 6, respectively (P < 0.001). 30-day mortality was 3.5%, 4.2%, 4.9%, 6.2%, 7.6%, 7.2% and 10.1% respectively (P < 0.001). 1-year mortality was 8.6%, 10.8%, 12.9%, 13.9%, 18.5%, 20.3% and 28.6% respectively (P < 0.001). 10-year survival was 61%, 56%, 57%, 54%, 47%, and 31% for patients with 0, 1, 2, 3, 4, 5 and ≥ 6 points respectively (P < 0.001). CONCLUSION: Perioperative mortality and long-term survival of patients undergoing LT can be accurately estimated at the time of listing by the LTRS.

Early subclinical tubulitis and interstitial inflammation in kidney transplantation have adverse clinical implications.

This prospective observational cohort study compared the impact of subclinical tubulitis with or without interstitial inflammation to interstitial inflammation alone and to no inflammation in early post kidney transplant biopsies. A study cohort of 415 patients (living and deceased donor recipients) was divided into three groups on the basis of their three-month biopsy: 149 patients with No Inflammation (NI), 83 patients with Isolated Interstitial Inflammation (IIF), and 183 patients with Tubulitis [(with or without interstitial inflammation) (TIF) but not meeting criteria for Banff IA]. TIF was further divided into 56 patients with tubulitis without interstitial inflammation (TIF0) and 127 patients with tubulitis alongside interstitial inflammation (TIF1). TIF was significantly associated with higher incidence of subsequent T-cell mediated rejection (clinical or subclinical) at one year compared to IIF (31% vs 15%) and NI (31% vs 17%). Chronicity on one-year biopsy was significantly higher in TIF compared to IIF (22% vs 11%) and NI (22% vs 7%). De novo donor-specific antibody development was significantly higher in TIF compared to NI (6% vs 0.7%). Tubulitis subgroups (TIF0 and TIF1) revealed comparable effects on de novo donor-specific antibody and interstitial fibrosis/tubular atrophy development. However, tubulitis with interstitial inflammation had a significantly higher incidence of subsequent rejection and posed an increased hazard for the composite end point (subsequent acute rejection and death censored graft loss) compared to other groups [adjusted hazard 2.1 (95% confidence interval 1.2-3.5)]. Thus, subclinical tubulitis is a marker of adverse immunological events, but tubulitis with interstitial inflammation has a worse prognosis. Hence, the Banff 1997 (TIF1) and Banff 2005 classifications (TIF) for borderline change may have different implications.

Epidemiology of end-stage renal failure among twins and diagnosis, management, and current outcomes of kidney transplantation between identical twins.

The aim of the study is to provide a comprehensive overview of identical twin kidney transplantation in the modern era. We provide epidemiologic trends in the US twin population from 1959 to 2000, current methods to identify zygosity, outcomes for identical twin transplants, and a comprehensive management strategy for identical twin kidney transplantation. By 2019, we project that 433 010 dizygotic and monozygotic twins will be alive and at risk for developing ESRF. Monozygosity between a donor-recipient pair can be confirmed by concordance in sex, blood type, and HLA antigen match with precision testing using 13/17 Short Tandem Repeat sequencing to a likelihood of nearly 100%. Among identical twin transplants from 2001 to 2017, excellent patient and kidney graft survival rates were noted. Approximately 50% of kidney transplant recipients of identical twins transplant did not receive maintenance immunosuppression, and no differences in graft survival were noted among patients with and without immunosuppression at 6 and 12 months (P = .8 and .7). Patients with glomerulonephritis as the cause of ESRF had lower graft survival (P = .06) suggesting that recurrent glomerulonephritis as a likely cause of graft loss among these recipients.

Donor acute kidney injury and its effect on 1-year post-transplant kidney allograft fibrosis.

Transplantation of kidneys from deceased donors with acute kidney injury (AKI) can expand the donor pool. We investigated the effect of donor AKI on renal function and chronic changes on protocol biopsies at 1-year post-transplant. Donor AKI was defined according to Acute Kidney Injury Network (AKIN) criteria. Between 2013 and 2017, 333 kidneys were transplanted and subsequently biopsied after 1 year. Fifty-three kidneys from AKI donors (AKIN stage I n = 42, stage II n = 8, stage III n = 3) were compared to 280 kidneys from non-AKI donors. At 1-year follow-up, patient and graft survival were comparable. Donor AKI was not predictive of IFTA (Banff interstitial fibrosis plus tubular atrophy scores) at 1-year post-transplant biopsy (2.10 ± 1.28 in AKI, 2.09 ± 1.22 in non-AKI, P = .95). Donor AKI was also not associated with progression of IFTA from 3 to 12 months (P = .69), or inferior glomerular filtration rate (eGFR, P = .94). In a multivariate analysis, the odds of IFTA >2 were comparable between AKI and non-AKI groups. In conclusion, the transplantation of kidneys from donors with predominantly stage I AKI results in comparable function and degree of fibrosis on protocol biopsies 1-year post-transplant. Selected grafts from donors with AKI are a valuable tool for expanding the donor pool for kidney transplantation.

Adult Living Donor Versus Deceased Donor Liver Transplant (LDLT Versus DDLT) at a Single Center: Time to Change Our Paradigm for Liver Transplant.

OBJECTIVE: The aim of this study was to compare outcomes between living donor liver transplant (LDLT) and deceased donor liver transplant (DDLT) at a single center to demonstrate the advantages of LDLT and provide justification for the increased utilization and application of this procedure. SUMMARY OF BACKGROUND DATA: LDLT comprises a very small percentage of all liver transplants performed in the United States, this despite its advantages and a shortage of the availability of deceased donor organs. METHODS: A retrospective review of all adult LDLT (n = 245) and DDLT (n = 592) performed at a single center over 10 years (2009-2019), comparing survival outcomes by Kaplan-Meier analysis and comparing other measures of outcome such as recovery times, complications, costs, and resource utilization. RESULTS: Patient survival outcomes were superior in LDLT recipients (3-year 86% vs 80%, P = 0.03). Other outcomes demonstrated shorter length of hospital stay (11 vs 13 days, P = 0.03), less likelihood of intraoperative blood transfusion (52% vs 78%, P < 0.01), and less likelihood of need for posttransplant dialysis (1.6% vs 7.4%, P < 0.01). Early reoperation and biliary/vascular complication rates were similar. Hospital costs related to the transplant were 29.5% lower for LDLT. Complications in living donors were acceptable with no early or late deaths, 3-month reoperation rate of 3.1%, and overall complication rate of 19.5%. Given its advantages, we have expanded LDLT-in 2018, LDLT comprised 53.6% of our transplants (national average 4.8%), and our transplant rate increased from 44.8 (rate per 100-person years) in 2015 to 87.5 in 2018. CONCLUSIONS: LDLT offers advantages over DDLT including superior outcomes and less resource utilization. The time has come to change the paradigm of how LDLT is utilized in this country.

A population neuroscience approach to the study of cerebral small vessel disease in midlife and late life: an invited review.

Aging in later life engenders numerous changes to the cerebral microvasculature. Such changes can remain clinically silent but are associated with greater risk for negative health outcomes over time. Knowledge is limited about the pathogenesis, prevention, and treatment of potentially detrimental changes in the cerebral microvasculature that occur with advancing age. In this review, we summarize literature on aging of the cerebral microvasculature, and we propose a conceptual framework to fill existing research gaps and advance future work on this heterogeneous phenomenon. We propose that the major gaps in this area are attributable to an incomplete characterization of cerebrovascular pathology, the populations being studied, and the temporality of exposure to risk factors. Specifically, currently available measures of age-related cerebral microvasculature changes are indirect, primarily related to parenchymal damage rather than direct quantification of small vessel damage, limiting the understanding of cerebral small vessel disease (cSVD) itself. Moreover, studies seldom account for variability in the health-related conditions or interactions with risk factors, which are likely determinants of cSVD pathogenesis. Finally, study designs are predominantly cross-sectional and/or have relied on single time point measures, leaving no clear evidence of time trajectories of risk factors or of change in cerebral microvasculature. We argue that more resources should be invested in 1) developing methodological approaches and basic science models to better understand the pathogenic and etiological nature of age-related brain microvascular diseases and 2) implementing state-of-the-science population study designs that account for the temporal evolution of cerebral microvascular changes in diverse populations across the lifespan.

Can Neuroimaging Markers of Vascular Pathology Explain Cognitive Performance in Adults With Sickle Cell Anemia? A review of the Literature.

Adults with homozygous sickle cell anemia have, on average, lower cognitive function than unaffected controls. The mechanisms underlying cognitive deterioration in this population are poorly understood, but cerebral small vessel disease (CSVD) is likely to be implicated. We conducted a systematic review using the Prisma Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines of articles that included both measures of cognitive function and magnetic resonance imaging (MRI) neuroimaging markers of small vessel disease. While all five studies we identified reported small vessel disease by MRI, only two of them found a significant relationship between structural changes and cognitive performance. Differences in methodologies and small sample sizes likely accounted for the discrepancies between the studies. We conclude that while MRI is a valuable tool to identify markers of CSVD in this population, larger studies are needed to definitely establish a link between MRI-detectable abnormalities and cognitive function in sickle cell anemia.

A glycine betaine importer limits Salmonella stress resistance and tissue colonization by reducing trehalose production.

Mechanisms by which Salmonella establish chronic infections are not well understood. Microbes respond to stress by importing or producing compatible solutes, small molecules that stabilize proteins and lipids. The Salmonella locus opuABCD (also called OpuC) encodes a predicted importer of the compatible solute glycine betaine. Under stress conditions, if glycine betaine cannot be imported, Salmonella enterica produce the disaccharide trehalose, a highly effective compatible solute. We demonstrate that strains lacking opuABCD accumulate more trehalose under stress conditions than wild-type strains. ΔopuABCD mutant strains are more resistant to high-salt, low-pH and -hydrogen peroxide, conditions that mimic aspects of innate immunity, in a trehalose-dependent manner. In addition, ΔopuABCD mutant strains require the trehalose production genes to out-compete wild-type strains in mice and macrophages. These data suggest that in the absence of opuABCD, trehalose accumulation increases bacterial resistance to stress in broth and mice. Thus, opuABCD reduces bacterial colonization via a mechanism that limits trehalose production. Mechanisms by which microbes limit disease may reveal novel pathways as therapeutic targets.

Outcomes and factors leading to graft failure in kidney transplants from deceased donors with acute kidney injury-A retrospective cohort study.

Due to shortage of donor, kidney transplants (KTs) from donors with acute kidney injury (AKI) are expanding. Although previous studies comparing clinical outcomes between AKI and non-AKI donors in KTs have shown comparable results, data on high-volume analysis of KTs outcomes with AKI donors are limited. This study aimed to analyze the selection trends of AKI donors and investigate the impact of AKI on graft failure using the United states cohort data. We analyzed a total 52,757 KTs collected in the Scientific Registry of Transplant Recipient (SRTR) from 2010 to 2015. The sample included 4,962 (9.4%) cases of KTs with AKI donors (creatinine ≥ 2 mg/dL). Clinical characteristics of AKI and non-AKI donors were analyzed and outcomes of both groups were compared. We also analyzed risk factors for graft failure in AKI donor KTs. Although the incidence of delayed graft function was higher in recipients of AKI donors compared to non-AKI donors, graft and patient survival were not significantly different between the two groups. We found donor hypertension, cold ischemic time, the proportion of African American donors, and high KDPI were risk factors for graft failure in AKI donor KTs. KTs from deceased donor with AKI showed comparable outcomes. Thus, donors with AKI need to be considered more actively to expand donor pool. Caution is still needed when donors have additional risk factors of graft failure.

Moderately Macrosteatotic Livers Have Acceptable Long-Term Outcomes but Higher Risk of Immediate Mortality.

BACKGROUND AND AIMS: Liver transplantation is the most effective treatment for end-stage liver disease (ESLD). Whether moderately macrosteatotic livers (30%-60%) represent a risk for worsened graft function is controversial. The uncertainty, in large part, is owing to the heterogeneous steatosis grading. Our aim was to determine the short- and long-term outcomes of moderately macrosteatotic allografts that were graded according to a standardized institutional protocol. METHODS: We performed a retrospective analysis of transplants performed between 1994 and 2014. All patients with allografts biopsied pretransplantation were included. Relevant donor and recipient variable were recorded. Moderately macrosteatotic livers were compared with mildly macrosteatotic and nonsteatotic livers. Primary outcomes of interest were patient survival at 90 days, 1 year, and 5 years. Cox regression analyses were carried out to compare survival between the 2 groups. RESULTS: We compared 65 allografts with moderate macrosteatosis and 810 with no or mild macrosteatosis. Patients with moderately macrosteatotic allografts were 2.69 times as likely to die within the first 90 days after transplant (75.1% vs 91.6% survival) after adjusting for donor age, donor race, recipient age, recipient race, recipient body mass index, recipient diabetes, presence of hepatocellular carcinoma, days on waitlist, Model for End-Stage Liver Disease (MELD) score at transplantation, cold ischemia time. However, for recipients who survive 90 days, moderately macrosteatotic allografts had comparable long-term survival. CONCLUSION: Our study shows that moderate macrosteatosis is a strong predictor of early but not late mortality. Further studies are needed to distinguish the specific cohort of patients for whom moderately macrosteatotic allografts will lead to acceptable outcomes.