Combining Blood Gene Expression and Cellfree DNA to Diagnose Subclinical Rejection in Kidney Transplant Recipients

BACKGROUND AND OBJECTIVES

Subclinical acute rejection is associated with poor outcomes in kidney transplant recipients. As an alternative to surveillance biopsies, noninvasive screening has been established with a blood gene expression profile. Donor-derived cellfree DNA (cfDNA) has been used to detect rejection in patients with allograft dysfunction but not tested extensively in stable patients. We hypothesized that we could complement noninvasive diagnostic performance for subclinical rejection by combining a donor-derived cfDNA and a gene expression profile assay.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a post hoc analysis of simultaneous blood gene expression profile and donor-derived cfDNA assays in 428 samples paired with surveillance biopsies from 208 subjects enrolled in an observational clinical trial (Clinical Trials in Organ Transplantation-08). Assay results were analyzed as binary variables, and then, their continuous scores were combined using logistic regression. The performance of each assay alone and in combination was compared.

RESULTS

For diagnosing subclinical rejection, the gene expression profile demonstrated a negative predictive value of 82%, a positive predictive value of 47%, a balanced accuracy of 64%, and an area under the receiver operating curve of 0.75. The donor-derived cfDNA assay showed similar negative predictive value (84%), positive predictive value (56%), balanced accuracy (68%), and area under the receiver operating curve (0.72). When both assays were negative, negative predictive value increased to 88%. When both assays were positive, positive predictive value increased to 81%. Combining assays using multivariable logistic regression, area under the receiver operating curve was 0.81, significantly higher than the gene expression profile (P<0.001) or donor-derived cfDNA alone (P=0.006). Notably, when cases were separated on the basis of rejection type, the gene expression profile was significantly better at detecting cellular rejection (area under the receiver operating curve, 0.80 versus 0.62; P=0.001), whereas the donor-derived cfDNA was significantly better at detecting antibody-mediated rejection (area under the receiver operating curve, 0.84 versus 0.71; P=0.003).

CONCLUSIONS

A combination of blood-based biomarkers can improve detection and provide less invasive monitoring for subclinical rejection. In this study, the gene expression profile detected more cellular rejection, whereas donor-derived cfDNA detected more antibody-mediated rejection.

Acute murine cytomegalovirus disrupts established transplantation tolerance and causes recipient allo-sensitization

We have previously shown that acute cytomegalovirus (CMV) infection disrupts the induction of transplantation tolerance. However, what impact acute CMV infection would have on the maintenance of established tolerance and on subsequent recipient allo-sensitization is a clinically important unanswered question. Here we used an allogeneic murine islet transplantation tolerance model to examine the impact of acute CMV infection on: (a) disruption of established transplantation tolerance during tolerance maintenance; and (b) the possibility of recipient allo-sensitization by CMV-mediated disruption of stable tolerance. We demonstrated that acute CMV infection abrogated transplantation tolerance during the maintenance stage in 50%-60% recipients. We further demonstrated that acute CMV infection-mediated tolerance disruption led to recipient allo-sensitization by reverting the tolerant state of allo-specific T cells and promoting their differentiation to allo-specific memory cells. Consequently, a second same-donor islet allograft was rejected in an accelerated fashion by these recipients. Our study therefore supports close monitoring for allo-sensitization in previously tolerant transplant recipients in whom tolerance maintenance is disrupted by an episode of acute CMV infection.

Kidney-intrinsic factors determine the severity of ischemia/reperfusion injury in a mouse model of delayed graft function

Delayed graft function due to transplant ischemia/reperfusion injury adversely affects up to 50% of deceased-donor kidney transplant recipients. However, key factors contributing to the severity of ischemia/reperfusion injury remain unclear. Here, using a clinically relevant mouse model of delayed graft function, we demonstrated that donor genetic background and kidney-intrinsic MyD88/Trif-dependent innate immunity were key determinants of delayed graft function. Functional deterioration of kidney grafts directly corresponded with the duration of cold ischemia time. The graft dysfunction became irreversible after cold ischemia time exceeded six hours. When cold ischemia time reached four hours, kidney grafts displayed histological features reflective of delayed graft function seen in clinical kidney transplantation. Notably, kidneys of B6 mice exhibited significantly more severe histological and functional impairment than kidneys of C3H or BALB/c mice, regardless of recipient strains or alloreactivities. Furthermore, allografts of B6 mice also showed an upregulation of IL-6, neutrophil gelatinase-associated lipocalin, and endoplasmic reticulum stress genes, as well as an increased influx of host neutrophils and memory CD8 T-cells. In contrast, donor MyD88/Trif deficiency inhibited neutrophil influx and decreased the expression of IL-6 and endoplasmic reticulum stress genes, along with improved graft function and prolonged allograft survival. Thus, kidney-intrinsic factors involving genetic characteristics and innate immunity serve as critical determinants of the severity of delayed graft function. This preclinical murine model allows for further investigations of the mechanisms underlying delayed graft function.

MCMV Dissemination from Latently-Infected Allografts Following Transplantation into Pre-Tolerized Recipients

Transplantation tolerance is achieved when recipients are unresponsive to donor alloantigen yet mobilize against third-party antigens, including virus. After transplantation, cytomegalovirus (CMV) reactivation in latently-infected transplants reduces allograft viability. To determine if pre-tolerized recipients are resistant to viral dissemination in this setting, we transfused chemically-fixed donor splenocytes (1-ethyl-3- (3′-dimethyl-aminopropyl)-carbo-diimide (ECDI)-treated splenocytes (ECDIsp)) to induce donor antigen tolerance without immunosuppression. In parallel, we implanted donor islet cells to validate operational tolerance. These pre-tolerized recipients were implanted with murine CMV (MCMV) latently-infected donor kidneys (a validated model of CMV latency) to monitor graft inflammation and viral dissemination. Our results indicate that tolerance to donor islets was sustained in recipients after implantation of donor kidneys. In addition, kidney allografts implanted after ECDIsp and islet implantation exhibited low levels of fibrosis and tubulitis. In contrast, kidney cellular and innate immune infiltrates trended higher in the CMV group and exhibited increased markers of CD8⁺ T cell activation. Tolerance induction was unable to prevent increases in MCMV-specific CD8⁺ T cells or dissemination of viral IE-1 DNA. Our data suggest that latently-infected allografts are inherently more susceptible to inflammation that is associated with viral dissemination in pre-tolerized recipients. Thus, CMV latently-infected allografts require enhanced strategies to protect allograft integrity and viral spread.

Kidney Graft Surveillance Biopsy Utilization and Trends: Results From a Survey of High-Volume Transplant Centers

An e-mail-based market research survey focused on high-volume US adult transplant centers was developed and implemented to assess surveillance based on United Network for Organ Sharing/Scientific Registry of Transplant Recipients data: 51 to 100 transplants, 101 to 200 transplants, and more than 200 transplants. Eighty-three centers responded to the survey. Respondent centers represented 13,837/21,167 (65%) of the total kidney transplants in 2018. In total, 38/83 (46%) centers reported the use of surveillance biopsies-20 centers in all patients and 18 in select patients. Surveillance biopsies were performed in 37% (7/19) of centers performing 51 to 100 transplants annually, in 44% (15/34) doing 101 to 200 transplants, and in 53% (16/30) of centers doing more than 200 transplants. Of the 20 centers doing surveillance biopsies in all patients, 17/20 (85%) perform more than 100 annual transplants, and 3/20 (15%) perform less than 100 annual transplants. Of the 45 centers not currently doing surveillance biopsies, 13 (29%) used surveillance biopsies in the past; discontinuation was primarily due to patient inconvenience, adverse events, and cost. Using survey percentages, it is estimated that surveillance biopsies are performed in approximately 34% of kidney transplant recipients and that 74% of all surveillance biopsies occur in centers performing more than 100 kidney transplants per year.

A novel murine model of differentiation-mediated cytomegalovirus reactivation from latently infected bone marrow haematopoietic cells

CD34+ myeloid lineage progenitor cells are an important reservoir of latent human cytomegalovirus (HCMV), and differentiation to macrophages or dendritic cells (DCs) is known to cause reactivation of latent virus. Due to its species-specificity, murine models have been used to study mouse CMV (MCMV) latency and reactivation in vivo. While previous studies have shown that MCMV genomic DNA can be detected in the bone marrow (BM) of latently infected mice, the identity of these cells has not been defined. Therefore, we sought to identify and enrich for cellular sites of MCMV latency in the BM haematopoietic system, and to explore the potential for establishing an in vitro model for reactivation of latent MCMV. We studied the kinetics and cellular characteristics of acute infection and establishment of latency in the BM of mice. We found that while MCMV can infect a broad range of haematopoietic BM cells (BMCs), latent virus is only detectable in haematopoietic stem cells (HSCs), myeloid progenitor cells, monocytes and DC-enriched cell subsets. Using three separate approaches, MCMV reactivation was detected in association with differentiation into DC-enriched BMCs cultured in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) followed by lipopolysaccharide (LPS) treatment. In summary, we have defined the kinetics and cellular profile of MCMV infection followed by the natural establishment of latency in vivo in the mouse BM haematopoietic system, including the haematopoietic phenotypes of cells that are permissive to acute infection, establish and harbour detectable latent virus, and can be stimulated to reactivate following DC enrichment and differentiation, followed by treatment with LPS.

A clinically relevant murine model unmasks a "two-hit" mechanism for reactivation and dissemination of cytomegalovirus after kidney transplant

Reactivation of latent cytomegalovirus remains an important complication after transplant. Although immunosuppression (IS) has been implicated as a primary cause, we have previously shown that the implantation response of a kidney allograft can lead to early transcriptional activation of latent murine cytomegalovirus (MCMV) genes in an immune-competent host and to MCMV reactivation and dissemination to other organs in a genetically immune-deficient recipient. We now describe a model that allows us to separately analyze the impact of the implantation effect vs that of a clinically relevant IS regimen. Treatment with IS of latently infected mice alone does not induce viral reactivation, but transplant of latently infected allogeneic kidneys combined with IS facilitates MCMV reactivation in the graft and dissemination to other organs. The IS regimen effectively dampens allo-immune inflammatory pathways and depletes recipient anti-MCMV but does not affect ischemia-reperfusion injury pathways. MCMV reactivation similar to that seen in allogeneic transplants combined with also occurs after syngeneic transplants. Thus, our data strongly suggest that while ischemia-reperfusion injury of the implanted graft is sufficient and necessary to initiate transcriptional reactivation of latent MCMV ("first hit"), IS is permissive to the first hit and facilitates dissemination to other organs ("second hit").

Immunometabolism of Phagocytes and Relationships to Cardiac Repair

Cardiovascular disease remains the leading cause of death worldwide. Myocardial ischemia is a major contributor to cardiovascular morbidity and mortality. In the case of acute myocardial infarction, subsequent cardiac repair relies upon the acute, and coordinated response to injury by innate myeloid phagocytes. This includes neutrophils, monocytes, macrophage subsets, and immature dendritic cells. Phagocytes function to remove necrotic cardiomyocytes, apoptotic inflammatory cells, and to remodel extracellular matrix. These innate immune cells also secrete cytokines and growth factors that promote tissue replacement through fibrosis and angiogenesis. Within the injured myocardium, macrophages polarize from pro-inflammatory to inflammation-resolving phenotypes. At the core of this functional plasticity is cellular metabolism, which has gained an appreciation for its integration with phagocyte function and remodeling of the transcriptional and epigenetic landscape. Immunometabolic rewiring is particularly relevant after ischemia and clinical reperfusion given the rapidly changing oxygen and metabolic milieu. Hypoxia reduces mitochondrial oxidative phosphorylation and leads to increased reliance on glycolysis, which can support biosynthesis of pro-inflammatory cytokines. Reoxygenation is permissive for shifts back to mitochondrial metabolism and fatty acid oxidation and this is ultimately linked to pro-reparative macrophage polarization. Improved understanding of mechanisms that regulate metabolic adaptations holds the potential to identify new metabolite targets and strategies to reduce cardiac damage through nutrient signaling.

Application of TruGraf v1: A Novel Molecular Biomarker for Managing Kidney Transplant Recipients With Stable Renal Function

TruGraf v1 is a laboratory-developed DNA microarray-based gene expression blood test to enable proactive noninvasive serial assessment of kidney transplant recipients with stable renal function. It has been previously validated in patients identified as Transplant eXcellence (TX: stable serum creatinine, normal biopsy results, indicative of immune quiescence), and not-TX (renal dysfunction and/or rejection on biopsy results). TruGraf v1 is intended for use in subjects with stable renal function to measure the immune status as an alternative to invasive, expensive, and risky surveillance biopsies.

MATERIALS AND METHODS

In this study, simultaneous blood tests and clinical assessments were performed in 192 patients from 7 transplant centers to evaluate TruGraf v1. The molecular testing laboratory was blinded to renal function and biopsy results.

RESULTS

Overall, TruGraf v1 accuracy (concordance between TruGraf v1 result and clinical and/or histologic assessment) was 74% (142/192), and a result of TX was accurate in 116 of 125 (93%). The negative predictive value for TruGraf v1 was 90%, with a sensitivity 74% and specificity of 73%. Results did not significantly differ in patients with a biopsy-confirmed diagnosis vs those without a biopsy.

CONCLUSIONS

TruGraf v1 can potentially support a clinical decision enabling unnecessary surveillance biopsies with high confidence, making it an invaluable addition to the transplant physician's tool kit for managing patients. TruGraf v1 testing can potentially avoid painful and risky invasive biopsies, reduce health care costs, and enable frequent assessment of patients with stable renal function to confirm the presence of immune quiescence in the peripheral blood.

Development and clinical validity of a novel blood-based molecular biomarker for subclinical acute rejection following kidney transplant

Noninvasive biomarkers are needed to monitor stable patients after kidney transplant (KT), because subclinical acute rejection (subAR), currently detectable only with surveillance biopsies, can lead to chronic rejection and graft loss. We conducted a multicenter study to develop a blood-based molecular biomarker for subAR using peripheral blood paired with surveillance biopsies and strict clinical phenotyping algorithms for discovery and validation. At a predefined threshold, 72% to 75% of KT recipients achieved a negative biomarker test correlating with the absence of subAR (negative predictive value: 78%-88%), while a positive test was obtained in 25% to 28% correlating with the presence of subAR (positive predictive value: 47%-61%). The clinical phenotype and biomarker independently and statistically correlated with a composite clinical endpoint (renal function, biopsy-proved acute rejection, ≥grade 2 interstitial fibrosis, and tubular atrophy), as well as with de novo donor-specific antibodies. We also found that <50% showed histologic improvement of subAR on follow-up biopsies despite treatment and that the biomarker could predict this outcome. Our data suggest that a blood-based biomarker that reduces the need for the indiscriminate use of invasive surveillance biopsies and that correlates with transplant outcomes could be used to monitor KT recipients with stable renal function, including after treatment for subAR, potentially improving KT outcomes.

Investigator Assessment of the Utility of the TruGraf Molecular Diagnostic Test in Clinical Practice

BACKGROUND

TruGraf v1 is a well-validated DNA microarray-based test that analyzes blood gene expression profiles as an indicator of immune status in kidney transplant recipients with stable renal function.

METHODS

In this study, investigators assessed clinical utility of the TruGraf test in patient management. In a retrospective study, simultaneous blood tests and clinical assessments were performed in 192 patients at 7 transplant centers, and in a prospective observational study they were performed in 45 subjects at 5 transplant centers.

RESULTS

When queried regarding whether or not the TruGraf test result impacted their decision regarding patient management, in 168 of 192 (87.5%) cases the investigator responded affirmatively. The prospective study indicated that TruGraf results supported physicians' decisions on patient management 87% (39/45) of the time, and in 93% of cases physicians indicated that they would use serial TruGraf testing in future patient management. A total of 21 of 39 (54%) reported results confirmed their decision that no intervention was needed, and 17 of 39 (44%) reported that results specifically informed them that a decision not to perform a surveillance biopsy was correct.

CONCLUSIONS

TruGraf is the first and only noninvasive test to be evaluated for clinical utility in determining rejection status of patients with stable renal function and shows promise of providing support for clinical decisions to avoid unnecessary surveillance biopsies with a high degree of confidence. TruGraf is an invaluable addition to the transplant physician's tool kit for managing patient health by avoiding painful and invasive biopsies, reducing health care costs, and enabling frequent assessment of patients with stable renal function to confirm immune quiescence.

Updated follow-up of a tolerance protocol in HLA-identical renal transplant pairs given donor hematopoietic stem cells

Kidney transplant recipients given donor hematopoietic stem cells from their HLA-identical living related donors have now been followed between 5 and 9½ years post-operatively. Recipients who were designated as tolerant (Tol) have remained so since the last report when the 5 year (biopsy associated) milestone was reached. There has been 1 mortality of a Tol patient, unrelated to the study protocol, while 5 (of 15) have remained Tol between 7 and 8½ years post-operatively. There has been continuing elevated T-regulatory (CD4⁺CD25^HighCD127^-FOXP3⁺) cells in PBMC previously reported on. Ten year renal transplant biopsies are tentatively planned.

A point-based prediction model for cardiovascular risk in orthotopic liver transplantation: The CAR-OLT score

Cardiovascular disease (CVD) complications are important causes of morbidity and mortality after orthotopic liver transplantation (OLT). There is currently no preoperative risk-assessment tool that allows physicians to estimate the risk for CVD events following OLT. We sought to develop a point-based prediction model (risk score) for CVD complications after OLT, the Cardiovascular Risk in Orthotopic Liver Transplantation risk score, among a cohort of 1,024 consecutive patients aged 18-75 years who underwent first OLT in a tertiary-care teaching hospital (2002-2011). The main outcome measures were major 1-year CVD complications, defined as death from a CVD cause or hospitalization for a major CVD event (myocardial infarction, revascularization, heart failure, atrial fibrillation, cardiac arrest, pulmonary embolism, and/or stroke). The bootstrap method yielded bias-corrected 95% confidence intervals for the regression coefficients of the final model. Among 1,024 first OLT recipients, major CVD complications occurred in 329 (32.1%). Variables selected for inclusion in the model (using model optimization strategies) included preoperative recipient age, sex, race, employment status, education status, history of hepatocellular carcinoma, diabetes, heart failure, atrial fibrillation, pulmonary or systemic hypertension, and respiratory failure. The discriminative performance of the point-based score (C statistic = 0.78, bias-corrected C statistic = 0.77) was superior to other published risk models for postoperative CVD morbidity and mortality, and it had appropriate calibration (Hosmer-Lemeshow P = 0.33).

CONCLUSION

The point-based risk score can identify patients at risk for CVD complications after OLT surgery (available at www.carolt.us); this score may be useful for identification of candidates for further risk stratification or other management strategies to improve CVD outcomes after OLT. (Hepatology 2017;66:1968-1979).

Mortality Risk Factors Among Patients With Cirrhosis and a Low Model for End-Stage Liver Disease Sodium Score (≤15): An Analysis of Liver Transplant Allocation Policy Using Aggregated Electronic Health Record Data

Although the Model for End-Stage Liver Disease sodium (MELD Na) score is now used for liver transplant allocation in the United States, mortality prediction may be underestimated by the score. Using aggregated electronic health record data from 7834 adult patients with cirrhosis, we determined whether the cause of cirrhosis or cirrhosis complications was associated with an increased risk of death among patients with a MELD Na score ≤15 and whether patients with the greatest risk of death could benefit from liver transplantation (LT). Over median follow-up of 2.3 years, 3715 patients had a maximum MELD Na score ≤15. Overall, 3.4% were waitlisted for LT. Severe hypoalbuminemia, hepatorenal syndrome, and hepatic hydrothorax conferred the greatest risk of death independent of MELD Na score with 1-year predicted mortality >14%. Approximately 10% possessed these risk factors. Of these high-risk patients, only 4% were waitlisted for LT, despite no difference in nonliver comorbidities between waitlisted patients and those not listed. In addition, risk factors for death among waitlisted patients were the same as those for patients not waitlisted, although the effect of malnutrition was significantly greater for waitlisted patients (hazard ratio 8.65 [95% CI 2.57-29.11] vs. 1.47 [95% CI 1.08-1.98]). Using the MELD Na score for allocation may continue to limit access to LT.

Comparative top down proteomics of peripheral blood mononuclear cells from kidney transplant recipients with normal kidney biopsies or acute rejection

Recent studies utilizing transcriptomics, metabolomics, and bottom up proteomics have identified molecular signatures of kidney allograft pathology. Although these results make significant progress toward non-invasive differential diagnostics of dysfunction of a transplanted kidney, they provide little information on the intact, often modified, protein molecules present during progression of this pathology. Because intact proteins underpin diverse biological processes, measuring the relative abundance of their modified forms promises to advance mechanistic understanding, and might provide a new class of biomarker candidates. Here, we used top down proteomics to inventory the modified forms of whole proteins in peripheral blood mononuclear cells (PBMCs) taken at the time of kidney biopsy for 40 kidney allograft recipients either with healthy transplants or those suffering acute rejection. Supported by gas-phase fragmentation of whole protein ions during tandem mass spectrometry, we identified 344 proteins mapping to 2905 distinct molecular forms (proteoforms). Using an initial implementation of a label-free approach to quantitative top down proteomics, we obtained evidence suggesting relative abundance changes in 111 proteoforms between the two patient groups. Collectively, our work is the first to catalog intact protein molecules in PBMCs and suggests differentially abundant proteoforms for further analysis.

Changes in Urinary Microbiome Populations Correlate in Kidney Transplants With Interstitial Fibrosis and Tubular Atrophy Documented in Early Surveillance Biopsies

An unbalanced microbiome may lead to disease by creating aberrant immune responses. A recent association of cellular rejection with the development of interstitial fibrosis and tubular atrophy (IFTA) suggests the role of immune-mediated tissue injury. We hypothesized that developing IFTA correlates with altered urinary tract microbiomes (UMBs). UMBs at two serial time points, 1 and 6-8 months posttransplant, were assessed by 16S microbial ribosomal gene sequencing in 25 patients developing biopsy-proven IFTA compared to 23 transplant patients with normal biopsies and excellent function (TX) and 20 healthy nontransplant controls (HC). Streptococcus, the dominant genera in HC males, was lower in IFTA and TX males at 1 month compared to HCs. At 6-8 months, Streptococcus was further decreased in IFTA males, but normalized in TX. IFTA males and females had increases in number of genera per sample at 6-8 months. UMB composition varied substantially between individuals in all groups. Despite the wide variation in UMBs between individuals, IFTA was associated with a loss in dominant resident urinary microbes in males, and a parallel increase in nonresident, pathogenic bacteria in males and females. UMB changes may contribute to IFTA development by alteration of the host immune response.

Exome Sequencing and Prediction of Long-Term Kidney Allograft Function

Current strategies to improve graft outcome following kidney transplantation consider information at the human leukocyte antigen (HLA) loci. Cell surface antigens, in addition to HLA, may serve as the stimuli as well as the targets for the anti-allograft immune response and influence long-term graft outcomes. We therefore performed exome sequencing of DNA from kidney graft recipients and their living donors and estimated all possible cell surface antigens mismatches for a given donor/recipient pair by computing the number of amino acid mismatches in trans-membrane proteins. We designated this tally as the allogenomics mismatch score (AMS). We examined the association between the AMS and post-transplant estimated glomerular filtration rate (eGFR) using mixed models, considering transplants from three independent cohorts (a total of 53 donor-recipient pairs, 106 exomes, and 239 eGFR measurements). We found that the AMS has a significant effect on eGFR (mixed model, effect size across the entire range of the score: -19.4 [-37.7, -1.1], P = 0.0042, χ2 = 8.1919, d.f. = 1) that is independent of the HLA-A, B, DR matching, donor age, and time post-transplantation. The AMS effect is consistent across the three independent cohorts studied and similar to the strong effect size of donor age. Taken together, these results show that the AMS, a novel tool to quantify amino acid mismatches in trans-membrane proteins in individual donor/recipient pair, is a strong, robust predictor of long-term graft function in kidney transplant recipients.

Medication understanding, non-adherence, and clinical outcomes among adult kidney transplant recipients

We sought to evaluate the prevalence of medication understanding and non-adherence of entire drug regimens among kidney transplantation (KT) recipients and to examine associations of these exposures with clinical outcomes. Structured, in-person interviews were conducted with 99 adult KT recipients between 2011 and 2012 at two transplant centers in Chicago, IL; and Atlanta, GA. Nearly, one-quarter (24%) of participants had limited literacy as measured by the Rapid Estimate of Adult Literacy in Medicine test; patients took a mean of 10 (SD=4) medications and 32% had a medication change within the last month. On average, patients knew what 91% of their medications were for (self-report) and demonstrated proper dosing (via observed demonstration) for 83% of medications. Overall, 35% were non-adherent based on either self-report or tacrolimus level. In multivariable analyses, fewer months since transplant and limited literacy were associated with non-adherence (all P<.05). Patients with minority race, a higher number of medications, and mild cognitive impairment had significantly lower treatment knowledge scores. Non-white race and lower income were associated with higher rates of hospitalization within a year following the interview. The identification of factors that predispose KT recipients to medication misunderstanding, non-adherence, and hospitalization could help target appropriate self-care interventions.

Functional Maturation of Induced Pluripotent Stem Cell Hepatocytes in Extracellular Matrix-A Comparative Analysis of Bioartificial Liver Microenvironments

The ability of two three-dimensional bioscaffold systems to reverse the primary limitations of induced pluripotent stem cell (iPSC)-derived hepatocytes was compared. Proliferation and function of iPSC hepatocytes were significantly enhanced when cultured within scaffolds made from extracellular matrix (ECM). This ECM scaffold enhanced phenotypic maturation of iPSC hepatocytes compared with other platforms, likely owing to its biologically diverse makeup.

Induced pluripotent stem cells (iPSCs) are new diagnostic and potentially therapeutic tools to model disease and assess the toxicity of pharmaceutical medications. A common limitation of cell lineages derived from iPSCs is a blunted phenotype compared with fully developed, endogenous cells. We examined the influence of novel three-dimensional bioartificial microenvironments on function and maturation of hepatocyte-like cells differentiated from iPSCs and grown within an acellular, liver-derived extracellular matrix (ECM) scaffold. In parallel, we also compared a bioplotted poly-l-lactic acid (PLLA) scaffold that allows for cell growth in three dimensions and formation of cell-cell contacts but is infused with type I collagen (PLLA-collagen scaffold) alone as a “deconstructed” control scaffold with narrowed biological diversity. iPSC-derived hepatocytes cultured within both scaffolds remained viable, became polarized, and formed bile canaliculi-like structures; however, cells grown within ECM scaffolds had significantly higher P450 (CYP2C9, CYP3A4, CYP1A2) mRNA levels and metabolic enzyme activity compared with iPSC hepatocytes grown in either bioplotted PLLA collagen or Matrigel sandwich control culture. Additionally, the rate of albumin synthesis approached the level of primary cryopreserved hepatocytes with lower transcription of fetal-specific genes, α-fetoprotein and CYP3A7, compared with either PLLA-collagen scaffolds or sandwich culture. These studies show that two acellular, three-dimensional culture systems increase the function of iPSC-derived hepatocytes. However, scaffolds derived from ECM alone induced further hepatocyte maturation compared with bioplotted PLLA-collagen scaffolds. This effect is likely mediated by the complex composition of ECM scaffolds in contrast to bioplotted scaffolds, suggesting their utility for in vitro hepatocyte assays or drug discovery.

Significance

Through the use of novel technology to develop three-dimensional (3D) scaffolds, the present study demonstrated that hepatocyte-like cells derived via induced pluripotent stem cell (iPSC) technology mature on 3D extracellular matrix scaffolds as a result of 3D matrix structure and scaffold biology. The result is an improved hepatic phenotype with increased synthetic and catalytic potency, an improvement on the blunted phenotype of iPSC-derived hepatocytes, a critical limitation of iPSC technology. These findings provide insight into the influence of 3D microenvironments on the viability, proliferation, and function of iPSC hepatocytes to yield a more mature population of cells for cell toxicity studies and disease modeling.

Abstract 161: Heart Failure Care Transitions: A Queuing Theory Approach to Match Variable Hospital Discharge Rate With Outpatient Clinic Capacity

Background: Heart failure (HF) readmissions remain a major driver of cost and health care utilization. Timely follow-up of patients post-discharge represents an evidence-based intervention proven to reduce readmission rates. A previously unexplored characteristic of hospital discharges is variability in discharge caseload. This variability thwarts the timeliness of follow-up, negates the benefit of transition care planning and may lead to a higher risk of HF readmissions. Queuing theory is the mathematical study of waiting times. We opted to use queuing theory to determine if caseload can be determined more precisely in a manner that sufficiently accommodates HF discharge variability.

Objective: To analyze the impact of hospital discharge rate variability on outpatient clinic capacity needs using HF hospitalization discharge data and operations management approaches.

Methods: Higher risk hospitalizations requiring active transitional care heart failure management were detected using an enterprise data warehouse-supported process over the study period. Queuing theory approaches were used to model the impact of HF discharge clinic capacity on wait time to an appointment. Discharge clinic was modeled as a single 7-day follow-up appointment, with an acceptable scheduling window of 5 to 9 days post-discharge.

Results: During the study period of 100 days, 566 HF discharges were made, for a median of 5.66 discharges daily, or 39.6 discharges weekly. The distribution of daily discharges was skewed rightward (mode = 3, range = 0 to 18, standard deviation = 3.3, coefficient of variation = 0.58). Current clinic design: Providing one discharge slot for every hospital discharge (100% utilization) leads to an average wait of 18.3 days prior to an appointment, with only 31.9% of appointments scheduled within 7 days, and 38.9% of appointments scheduled within 9 days. Clinic re-design (queuing theory): Providing five extra discharge appointment slots per week (88% utilization or 13.6% excess capacity) reduces the expected waiting period to 1.1 days, with 99.8% of patients seen within 7 days, and virtually all patients seen within 9 days of discharge.

Conclusions: Deployment of queuing theory allows for a more precise quantification of needed clinical capacity to accomplish appropriate HF follow-up with a reasonable degree of certainty. Our simplified model demonstrates that variability in hospital discharge rates leads to excessive clinic wait times in the absence of a modest capacity buffer and consequently exposes patients to a higher risk of HF readmission. We show using single center HF discharge data that a 10-15% increase in capacity is needed to ensure an adequate follow-up service level. Ongoing process of care work will demonstrate if optimization of clinic load yields a significant reduction in HF readmissions.

Abstract 152: Enterprise Data Warehouse-Supported Early Identification of Acute Decompensated Heart Failure Admissions for Efficient and Multidisciplinary Transitional Care Team Interventions

Background: Multidisciplinary transitional care teams represent a model for reducing heart failure readmissions. Within this context, early identification of patients hospitalized with acute decompensated heart failure (ADHF) permits meaningful transitional care plan development. Improving the efficiency of early identification of the higher risk ADHF patient represents an area not well studied in hospitalized heart failure (HF).

Objective: To validate the sensitivity and specificity of an enterprise data warehouse (EDW)-based strategy for early identification of patients with ADHF.

Methods: An EDW query was constructed to identify patients with ADHF based on clinical and diagnosis-related parameters, including BNP level and administration of intravenous diuretics. The EDW query was run daily; expert clinicians verified the diagnosis of ADHF based on comprehensive chart review. This classification was used to determine specificity of the query for ADHF. We computed the sensitivity of the EDW-based approach by matching query results to heart failure diagnosis related group (DRG) data and primary discharge diagnosis data from separate hospital systems.

Results: During the study period of 70 days, a total of 2354 charts were screened (33.6 charts per day). A total of 410 patients were identified by chart review as having heart failure requiring active management, for a specificity of 17.4%. Sensitivity was computed using both heart failure DRG data and primary discharge diagnosis data. Of the 114 patients discharged with a heart failure DRG (291, 292, or 293), all 114 were detected a priori by the admission EDW screen, for a sensitivity of 100%. A similar analysis conducted using HF principal diagnoses, which includes cardiac surgery-related admissions, yielded a sensitivity of 97.2%.

Conclusions: EDW-based screening of patients based on simple clinical parameters early in the hospitalization is highly sensitive for detection of ADHF hospitalizations, but specificity is low. Brief chart review by expert clinicians is rapid, and identifies a specific cohort of patients that can be targeted for multidisciplinary HF transitional care. A better delineation of risk has broad outpatient workflow implications. Ongoing process improvements will demonstrate if early identification of at-risk patients yields significant reduction in HF readmissions.

Applying the WHO conceptual framework for the International Classification for Patient Safety to a surgical population

OBJECTIVE

Efforts to improve patient safety are challenged by the lack of universally agreed upon terms. The International Classification for Patient Safety (ICPS) was developed by the World Health Organization for this purpose. This study aimed to test the applicability of the ICPS to a surgical population.

DESIGN

A web-based safety debriefing was sent to clinicians involved in surgical care of abdominal organ transplant patients. A multidisciplinary team of patient safety experts, surgeons and researchers used the data to develop a system of classification based on the ICPS. Disagreements were reconciled via consensus, and a codebook was developed for future use by researchers.

RESULTS

A total of 320 debriefing responses were used for the initial review and codebook development. In total, the 320 debriefing responses contained 227 patient safety incidents (range: 0-7 per debriefing) and 156 contributing factors/hazards (0-5 per response). The most common severity classification was 'reportable circumstance,' followed by 'near miss.' The most common incident types were 'resources/organizational management,' followed by 'medical device/equipment.' Several aspects of surgical care were encompassed by more than one classification, including operating room scheduling, delays in care, trainee-related incidents, interruptions and handoffs.

CONCLUSIONS

This study demonstrates that a framework for patient safety can be applied to facilitate the organization and analysis of surgical safety data. Several unique aspects of surgical care require consideration, and by using a standardized framework for describing concepts, research findings can be compared and disseminated across surgical specialties. The codebook is intended for use as a framework for other specialties and institutions.

Unintended Consequences of the New National Kidney Allocation Policy in the United States

The new national Kidney Allocation System of the Organ Procurement and Transplantation Network (OPTN), effective as of December 4, 2014, was designed to improve the chances of transplanting the most highly sensitized patients on the waitlist, those with calculated panel reactive antibody values of 98%, 99% and 100%. Recently, it was suggested that these highly sensitized patients will experience inequitable access, given the reported high prevalence of antibodies to HLA-DP, and the fact that only about 1/3 of deceased donors are typed for HLA-DP antigens. Here we report that 320/2948 flow cytometric crossmatches performed for the Northwestern transplant program over the past 28 months were positive solely due to HLA-DP donor-specific antibodies (11%; 16.5% of patients with HLA antibodies-sensitized patients). We further show that 58/207 (12%) HLA-DR serologically matched donor-recipient pairs had a positive B cell flow crossmatch due to donor-specific HLA class II antibodies, and 2/34 (6%) serologic zero-HLA-A-B-DR mismatch had a positive flow crossmatch due to HLA-DSA. We therefore provide information regarding the necessity and importance of complete donor HLA typing including both chains of the HLA-DP antigen (encoded by HLA-DPA1 and HLA-DPB1) at the time of organ offer.

Clinician perceptions of operating room to intensive care unit handoffs and implications for patient safety: a qualitative study

BACKGROUND

Operating room (OR) to the intensive care unit (ICU) handoffs are known sources of medical error, yet little is known about the relationship between process failures and patient harm.

METHODS

Interviews were conducted with clinicians involved in the OR-to-ICU handoff to characterize the relationship between handoff process failures and patient harm. Qualitative analysis was used to inductively identify key themes.

RESULTS

A total of 38 interviews were conducted. Dominant themes included early communication from the OR to the ICU, team member participation in the handoff, and relationships between clinicians; clinician perspectives varied depending substantially on role within the team.

CONCLUSIONS

The findings suggest that ambiguous roles and conflicting expectations of team members during the OR-to-ICU handoff can increase risk of patient harm. Future studies should investigate early postoperative ICU care as outcome markers of handoff quality and the effect of interprofessional education on clinician adherence to interventions.

Operating room to intensive care unit handoffs and the risks of patient harm

BACKGROUND

The goal of this study was to assess systems and processes involved in the operating room (OR) to intensive care unit (ICU) handoff in an attempt to understand the criticality of specific steps of the handoff.

METHODS

We performed a failure modes, effects, and criticality analysis (FMECA) of the OR to ICU handoff of deceased donor liver transplant recipients using in-person observations and descriptions of the handoff process from a multidisciplinary group of clinicians. For each step in the process, failures were identified along with frequency of occurrence, causes, potential effects and safeguards. A Risk Priority Number (RPN) was calculated for each failure (frequency × potential effect × safeguard; range 1-least risk to 1,000-most risk).

RESULTS

Using FMECA, we identified 37 individual steps in the OR to ICU handoff process. In total, 81 process failures were identified, 22 of which were determined to be critical and 36 of which relied on weak safeguards such as informal human verification. Process failures with the greatest risk of harm were lack of preliminary OR to ICU communication (RPN 504), team member absence during handoff communication (RPN 480), and transport equipment malfunction (Risk Priority Number 448).

CONCLUSION

Based on the analysis, recommendations were made to reduce potential for patient harm during OR to ICU handoffs. These included automated transfer of OR data to ICU clinicians, enhanced ICU team member notification processes and revision of the postoperative order sets. The FMECA revealed steps in the OR to ICU handoff that are high risk for patient harm and are currently being targeted for process improvement.

Recipient Myd88 Deficiency Promotes Spontaneous Resolution of Kidney Allograft Rejection

The myeloid differentiation protein 88 (MyD88) adapter protein is an important mediator of kidney allograft rejection, yet the precise role of MyD88 signaling in directing the host immune response toward the development of kidney allograft rejection remains unclear. Using a stringent mouse model of allogeneic kidney transplantation, we demonstrated that acute allograft rejection occurred equally in MyD88-sufficient (wild-type [WT]) and MyD88(-/-) recipients. However, MyD88 deficiency resulted in spontaneous diminution of graft infiltrating effector cells, including CD11b(-)Gr-1(+) cells and activated CD8 T cells, as well as subsequent restoration of near-normal renal graft function, leading to long-term kidney allograft acceptance. Compared with T cells from WT recipients, T cells from MyD88(-/-) recipients failed to mount a robust recall response upon donor antigen restimulation in mixed lymphocyte cultures ex vivo. Notably, exogenous IL-6 restored the proliferation rate of T cells, particularly CD8 T cells, from MyD88(-/-) recipients to the proliferation rate of cells from WT recipients. Furthermore, MyD88(-/-) T cells exhibited diminished expression of chemokine receptors, specifically CCR4 and CXCR3, and the impaired ability to accumulate in the kidney allografts despite an otherwise MyD88-sufficient environment. These results provide a mechanism linking the lack of intrinsic MyD88 signaling in T cells to the effective control of the rejection response that results in spontaneous resolution of acute rejection and long-term graft protection.

Optimization and critical evaluation of decellularization strategies to develop renal extracellular matrix scaffolds as biological templates for organ engineering and transplantation

The ability to generate patient-specific cells through induced pluripotent stem cell (iPSC) technology has encouraged development of three-dimensional extracellular matrix (ECM) scaffolds as bioactive substrates for cell differentiation with the long-range goal of bioengineering organs for transplantation. Perfusion decellularization uses the vasculature to remove resident cells, leaving an intact ECM template wherein new cells grow; however, a rigorous evaluative framework assessing ECM structural and biochemical quality is lacking. To address this, we developed histologic scoring systems to quantify fundamental characteristics of decellularized rodent kidneys: ECM structure (tubules, vessels, glomeruli) and cell removal. We also assessed growth factor retention--indicating matrix biofunctionality. These scoring systems evaluated three strategies developed to decellularize kidneys (1% Triton X-100, 1% Triton X-100/0.1% sodium dodecyl sulfate (SDS) and 0.02% Trypsin-0.05% EGTA/1% Triton X-100). Triton and Triton/SDS preserved renal microarchitecture and retained matrix-bound basic fibroblast growth factor and vascular endothelial growth factor. Trypsin caused structural deterioration and growth factor loss. Triton/SDS-decellularized scaffolds maintained 3 h of leak-free blood flow in a rodent transplantation model and supported repopulation with human iPSC-derived endothelial cells and tubular epithelial cells ex vivo. Taken together, we identify an optimal Triton/SDS-based decellularization strategy that produces a biomatrix that may ultimately serve as a rodent model for kidney bioengineering.

Medication misuse, nonadherence, and clinical outcomes among liver transplant recipients

Medication nonadherence after liver transplantation (LT) is associated with adverse clinical outcomes such as graft rejection and graft loss. Few studies have examined nonadherence and its impact on clinical outcomes in LT. The study objectives were (1) to evaluate medication understanding (with treatment knowledge and demonstrated regimen use scores) and medication adherence or nonadherence to entire regimens among LT recipients and (2) to examine associations of these exposures with clinical outcomes. We conducted a 2-site study of 105 recipients between 2011 and 2012 at 2 transplant centers in Chicago, IL and Atlanta, GA. Data were collected via detailed, in-person interviews and medical record reviews. Study participants were middle-aged and predominantly male; 15% of the sample had limited literacy. On average, patients were taking 11 medications [standard deviation (SD) = 4], and 39% had undergone a medication change within the last month. The average scores for the entire medication regimen were 86% (SD = 22%) for treatment knowledge and 78% (SD = 22%) for demonstrated regimen use. The mean score for self-reported nonadherence to the entire regimen was 14% (SD = 20%), whereas 32% of the patients were nonadherent according to tacrolimus levels. In multivariate analyses, lower income, less time since transplantation, a higher number of medications, and limited literacy were inversely associated with treatment knowledge scores (all P < 0.05), whereas limited literacy was associated with nonadherence according to tacrolimus levels (P < 0.05). In multivariate models, higher scores for treatment knowledge [incidence rate ratio (IRR) = 0.85, 95% confidence interval (CI) = 0.74-0.97] and demonstrated regimen use (IRR = 0.87, 95% confidence interval = 0.77-0.98) were independently associated with 15% and 13% reductions in the number of posttransplant rehospitalizations, respectively. Inadequate treatment knowledge and improper regimen use may be significant determinants of unintentional nonadherence among LT recipients and are associated with adverse clinical outcomes.

Plasma protein biomarkers enhance the clinical prediction of kidney injury recovery in patients undergoing liver transplantation

Biomarkers predictive of recovery from acute kidney injury (AKI) after liver transplantation (LT) could enhance decision algorithms regarding the need for liver-kidney transplantation or renal sparing regimens. Multianalyte plasma/urine kidney injury protein panels were performed immediately before and 1 month post-LT in an initial test group divided by reversible pre-LT AKI (rAKI = post-LT renal recovery) versus no AKI (nAKI). This was followed by a larger validation set that included an additional group: irreversible pre-LT AKI (iAKI = no post-LT renal recovery). In the test group (n = 16), six pre-LT plasma (not urine) kidney injury proteins (osteopontin [OPN], neutrophil gelatinase-associated lipocalin, cystatin C, trefoil factor 3, tissue inhibitor of metalloproteinase [TIMP]-1, and β-2-microglobulin) were higher in rAKI versus nAKI (P < 0.05) and returned to normal values with renal recovery post-LT. In the validation set (n = 46), a number of proteins were significantly higher in both rAKI and iAKI versus nAKI. However, only pre-LT plasma OPN (P = 0.009) and TIMP-1 (P = 0.019) levels were significantly higher in rAKI versus iAKI. Logistic regression modeling was used to correlate the probability of post-LT rAKI, factoring in both pre-LT protein markers and clinical variables. A combined model including elevated OPN and TIMP-1 levels, age <57, and absence of diabetes had the highest area under the curve of 0.82, compared to protein-only and clinical variable-only models.

CONCLUSION

These data suggest that plasma protein profiles might improve the prediction of pre-LT kidney injury recovery after LT. However, multicenter, prospective studies are needed to validate these findings and ultimately test the value of such protein panels in perioperative management and decision making.

The use of technology for urgent clinician to clinician communications: a systematic review of the literature

OBJECTIVE

Urgent clinician-clinician communications require routes of contact that are fast and dependable, and allow for the exchange of complex information. Despite the increasing focus on improving healthcare delivery systems over the past decade, few studies have examined the role of technology in clinician-clinician communication. The aim of this study was to review the literature examining the role of devices and technology in facilitating urgent clinician-clinician communication to identify critical areas for future research.

MATERIALS AND METHODS

A search of Pub Med was performed using the terms (((("Critical Care"[Mesh] OR "urgent")))) AND (((hospital communication systems[MeSH Terms]) OR health communication[MeSH Terms]) OR interdisciplinary communication[MeSH Terms]). Commentaries and editorials were excluded.

RESULTS

The initial search returned 272 articles, which were reviewed to identify articles describing: (1) the role of technological support or devices in clinician-clinician communication, (2) technology-based interventions that improved clinician-to-clinician communication in hospitals or acute care facilities related to critically ill patients, or (3) critical information exchange. A total of 16 articles were included in the final review. These were grouped into three categories: alphanumeric pagers, cellular and smart telephones, and novel uses of technology.

DISCUSSION

Breakdowns in clinician-clinician communication are complex and cannot be solved through the implementation of devices or technologically advanced systems alone. It is essential to understand the correlation between emerging technologies, a demanding workload, and clinician-clinician interaction. Enhanced communication of clinical ideas, opportunities for team discussion, and a sense of partnership and support require not just increased information, but enhanced delivery.

Improving Geographic Equity in Kidney Transplantation Using Alternative Kidney Sharing and Optimization Modeling

The national demand for kidney transplantation far outweighs the supply of kidney organs. Currently, a patient's ability to receive a kidney transplant varies depending on where he or she seeks transplantation. This reality is in direct conflict with a federal mandate from the Department of Health and Human Services. We analyze current kidney allocation and develop an alternative kidney sharing strategy using a multiperiod linear optimization model, KSHARE. KSHARE aims to improve geographic equity in kidney transplantation while also respecting transplant system constraints and priorities. KSHARE is tested against actual 2000–2009 kidney allocation using Organ Procurement and Transplant Network data. Geographic equity is represented by minimizing the range in kidney transplant rates around local areas of the country. In 2009, less than 25% of standard criteria donor kidneys were allocated beyond the local area of procurement, and Donor Service Area kidney transplantation rates varied from 3.0% to 30.0%, for an overall range of 27.0%. Given optimal sharing of kidneys within 600 miles of procurement for 2000–2009, kidney transplant rates vary from 5.0% to 12.5% around the country for an overall kidney transplant range of 7.5%. Nationally sharing kidneys optimally between local areas only further decreases the transplant rate range by 1.7%. Enhancing the practice of sharing kidneys by the KSHARE model may increase geographic equity in kidney transplantation.

High early cardiovascular mortality after liver transplantation

Cardiovascular disease (CVD) contributes to excessive long-term mortality after liver transplantation (LT); however, little is known about early postoperative CVD mortality in the current era. In addition, there is no model for predicting early postoperative CVD mortality across centers. We analyzed adult recipients of primary LT in the Organ Procurement and Transplantation Network (OPTN) database between February 2002 and December 2012 to assess the prevalence and predictors of early (30-day) CVD mortality, which was defined as death from arrhythmia, heart failure, myocardial infarction, cardiac arrest, thromboembolism, and/or stroke. We performed logistic regression with stepwise selection to develop a predictive model of early CVD mortality. Sex and center volume were forced into the final model, which was validated with bootstrapping techniques. Among 54,697 LT recipients, there were 1576 deaths (2.9%) within 30 days. CVD death was the leading cause of 30-day mortality (40.2%), and it was followed by infection (27.9%) and graft failure (12.2%). In a multivariate analysis, 9 significant covariates (6 recipient covariates, 2 donor covariates, and 1 operative covariate) were identified: age, preoperative hospitalization, intensive care unit status, ventilator status, calculated Model for End-Stage Liver Disease score, portal vein thrombosis, national organ sharing, donor body mass index, and cold ischemia time. The model showed moderate discrimination (C statistic = 0.66, 95% confidence interval = 0.63-0.68). In conclusion, we provide the first multicenter prognostic model for the prediction of early post-LT CVD death, the most common cause of early post-LT mortality in the current transplant era. However, evaluations of additional CVD-related variables not collected by the OPTN are needed in order to improve the model's accuracy and potential clinical utility.

A meta-analysis of complications following deceased donor liver transplant

BACKGROUND

Liver transplantation is a complex surgery associated with high rates of postoperative complications. While national outcomes data are available, national rates of most complications are unknown.

DATA SOURCES

A systematic review of the literature reporting rates of postoperative complications between 2002 and 2012 was performed. A cohort of 29,227 deceased donor liver transplant recipients from 74 studies was used to calculate pooled incidences for 17 major postoperative complications.

CONCLUSIONS

This is the first comprehensive review of postoperative complications after liver transplantation and can serve as a guide for transplant and nontransplant clinicians. Efforts to collect national data on complications, such as through the National Surgical Quality Improvement Program, would improve the ability to provide patients with informed consent, serve as a tool for individual center performance monitoring, and provide a central source against which to measure interventions aimed at improving patient care.

Culturally competent transplant program improves Hispanics' knowledge and attitudes about live kidney donation and transplant

CONTEXT

Hispanics receive disproportionately fewer live donor kidney transplants than non-Hispanic whites. Increasing Hispanics' knowledge and changing attitudes about live kidney donation may reduce these disparities.

OBJECTIVE

To evaluate the effectiveness of culturally and linguistically competent educational sessions delivered through Northwestern University's Hispanic Transplant Program.

DESIGN

Baseline and postsession questionnaires were used to evaluate changes in patients' and family members' knowledge and attitudes toward live kidney donation and program satisfaction. Knowledge items related to live kidney donation were scaled, and changes in scores were evaluated via a paired t test. Multiple regression analysis of follow-up knowledge scores controlled for baseline scores was used to estimate the effects of patients' and families' sociodemographic characteristics. Changes in attitude items, including comfort with exploring live kidney donation, were analyzed with χ2 tests.

RESULTS

One-hundred thirteen patients and family members completed surveys before and after an education session. Respondents' knowledge about live kidney donation and transplant increased significantly (P<.001) between baseline and after the session. Patients' attitudes toward live kidney donation became more favorable (P< .02), as did family members' attitudes toward being a donor (P < .001) after participating in the program. All respondents reported high levels of satisfaction with the program and preferences for culturally congruent care.

CONCLUSIONS

The educational sessions provided by the Hispanic Transplant Program effectively addressed commonly shared Hispanic concerns about live kidney donation. Culturally congruent education increased Hispanic patients' and family members' knowledge and improved attitudes about live donor kidney transplants.

Increased quality of life among hepatocellular carcinoma patients treated with radioembolization, compared with chemoembolization

BACKGROUND & AIMS

Quality of life (QoL) is an important aspect of any palliative treatment. However, few data are available from studies comparing how embolotherapy affects QoL for patients with hepatocellular carcinoma (HCC). We performed a health-related QoL study in patients with HCC treated by transarterial chemoembolization (TACE) or (90)Y radioembolization.

METHODS

We performed a prospective study of patients undergoing (90)Y radioembolization (n = 29) or TACE (n = 27) for HCC. We assessed patients before treatment and 2 and 4 weeks after treatment using the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) survey. We compared differences in health-related QoL between the treatment groups using linear regression repeated-measures analysis.

RESULTS

At baseline, the groups had comparable baseline Child-Pugh class and performance statuses, although patients undergoing TACE had lower tumor burdens (P = .018) and less-advanced disease, based on United Network for Organ Sharing and Barcelona stage (P = .03 and P = .02, respectively), permitting injections at segmental arteries (P < .0001). There were no significant differences between groups in overall FACT-Hep health-related QoL scores (P = .055, effect size [ES], .54), owing to a limited sample size. Despite the more advanced disease of patients who received (90)Y radioembolization, they had a significantly better QoL, based on social well being (P = .019; ES, .65), functional well-being (P = .031; ES, .60), and embolotherapy-specific scores (P = .018; ES, .67). They also had a trend toward better overall QoL (P = .055; ES, .54) and higher Trial Outcome Index (P = .05; ES, .56) and FACT-Hep scores (P = .071; ES, .52).

CONCLUSIONS

In a prospective study, although (90)Y radioembolization was used to treat patients with more advanced disease, those who received this treatment had significant increases in several features of QoL, whereas patients who received TACE had decreases in QoL scores. However, because of the limited sample size, there was no significant difference in overall FACT-Hep health-related QoL scores. The increase was greatest in the embolotherapy-specific score. ClinicalTrials.gov, number NCT00739167.

Yttrium-90 radioembolization for the treatment of unresectable hepatocellular carcinoma in patients with transjugular intrahepatic portosystemic shunts

PURPOSE

To evaluate the toxicity and response to radioembolization with yttrium-90 ((90)Y) glass microspheres in patients with hepatocellular carcinoma (HCC) and existing transjugular intrahepatic portosystemic shunts (TIPS).

MATERIALS AND METHODS

For treatment of unresectable HCC, 12 patients with a patent TIPS underwent a total of 21 infusions of (90)Y. Toxicity within 90 days of treatment was assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE v4.0). Imaging response within the index lesion was assessed using the World Health Organization (WHO) and European Association for the Study of the Liver (EASL) guidelines. Survival was calculated using the Kaplan-Meier method.

RESULTS

All patients had a patent TIPS on imaging before treatment. Clinical toxicities included fatigue (83%), encephalopathy (33%), and abdominal pain (25%). Three patients (25%) experienced new grade 3 or 4 bilirubin toxicity. Imaging response was achieved in 50% and 67% of patients according to WHO and EASL criteria. Six patients (50%) went on to liver transplantation. Median survival censored for liver transplantation was 498 days (95% confidence interval [CI],100-800 d), and uncensored median survival was 827 days (95% CI, 250-2,400 d).

CONCLUSIONS

(90)Y radioembolization may be a safe and effective treatment for patients with unresectable HCC and existing TIPS. This minimally embolic therapy may be particularly useful as a bridge to curative liver transplantation.

The emergence of top-down proteomics in clinical research

Proteomic technology has advanced steadily since the development of 'soft-ionization' techniques for mass-spectrometry-based molecular identification more than two decades ago. Now, the large-scale analysis of proteins (proteomics) is a mainstay of biological research and clinical translation, with researchers seeking molecular diagnostics, as well as protein-based markers for personalized medicine. Proteomic strategies using the protease trypsin (known as bottom-up proteomics) were the first to be developed and optimized and form the dominant approach at present. However, researchers are now beginning to understand the limitations of bottom-up techniques, namely the inability to characterize and quantify intact protein molecules from a complex mixture of digested peptides. To overcome these limitations, several laboratories are taking a whole-protein-based approach, in which intact protein molecules are the analytical targets for characterization and quantification. We discuss these top-down techniques and how they have been applied to clinical research and are likely to be applied in the near future. Given the recent improvements in mass-spectrometry-based proteomics and stronger cooperation between researchers, clinicians and statisticians, both peptide-based (bottom-up) strategies and whole-protein-based (top-down) strategies are set to complement each other and help researchers and clinicians better understand and detect complex disease phenotypes.

Opportunities for shared decision making in kidney transplantation

Health researchers and policy-makers increasingly urge both patient and clinician engagement in shared decision making (SDM) to promote patient-centered care. Although SDM has been examined in numerous clinical settings, it has received little attention in solid organ transplantation. This paper describes the application of SDM to the kidney transplantation context. Several distinctive features of kidney transplantation present challenges to SDM including fragmented patient-provider relationships, the time-sensitive and unpredictable nature of deceased organ offers, decision-making processes by transplant providers serving as both organ guardians (given the organ scarcity) versus advocates for specific patients seeking transplantation, variable clinical practices and policies among transplant centers, and patients' potentially compromised cognitive status and literacy levels. We describe potential barriers to and opportunities for SDM, and posit that SDM is feasible, warranting encouragement in kidney transplantation. We propose strategies to promote and overcome obstacles to SDM in kidney transplantation. We contend that engagement in SDM can be facilitated by re-organization of clinical care, communication and education of providers and patients.

NUTORC-a transdisciplinary health services and outcomes research team in transplantation

The field of solid organ transplantation has historically concentrated research efforts on basic science and translational studies. However, there has been increasing interest in health services and outcomes research. The aim was to build an effective and sustainable, inter- and transdisciplinary health services and outcomes research team (NUTORC), that leveraged institutional strengths in social science, engineering, and management disciplines, coupled with an international recognized transplant program. In 2008, leading methodological experts across the university were identified and intramural funding was obtained for the NUTORC initiative. Inter- and transdisciplinary collaborative teams were created across departments and schools within the university. Within 3 years, NUTORC became fiscally sustainable, yielding more than tenfold return of the initial investment. Academic productivity included funding for 39 grants, publication of 60 manuscripts, and 166 national presentations. Sustainable educational opportunities for students were created. Inter- and transdisciplinary health services and outcomes research in transplant can be innovative and sustainable.

Outcomes and native renal recovery following simultaneous liver-kidney transplantation

With the increase in patients having impaired renal function at liver transplant due to MELD, accurate predictors of posttransplant native renal recovery are needed to select candidates for simultaneous liver-kidney transplantation (SLK). Current UNOS guidelines rely on specific clinical criteria for SLK allocation. To examine these guidelines and other variables predicting nonrecovery, we analyzed 155 SLK recipients, focusing on a subset (n = 78) that had post-SLK native GFR (nGFR) determined by radionuclide renal scans. The 77 patients not having renal scans received a higher number of extended criteria donor organs and had worse posttransplant survival. Of the 78 renal scan patients, 31 met and 47 did not meet pre-SLK UNOS criteria. The UNOS criteria were more predictive than our institutional criteria for all nGFR recovery thresholds (20-40 mL/min), although at the most conservative cut-off (nGFR ≤ 20) it had low sensitivity (55.3%), specificity (75%), PPV (67.6%) and NPV (63.8%) for predicting post-SLK nonrecovery. On multivariate analysis, the only predictor of native renal nonrecovery (nGFR ≤ 20) was abnormal pre-SLK renal imaging (OR 3.85, CI 1.22-12.5). Our data support the need to refine SLK selection utilizing more definitive biomarkers and predictors of native renal recovery than current clinical criteria.