Utility of phosphatidylethanol testing in liver transplant evaluation: examining concordance to self-reported alcohol use

Cannabis use in liver transplant candidates and recipients

The increasing legality and acceptance of cannabis sale and consumption across the United States has led to a measurable increase in cannabis use nationwide, including in liver transplant (LT) candidates and recipients. With over 75% of liver transplant recipients transplanted in states with legalized use of medicinal and/or recreational cannabis, liver transplant clinicians must have expertise in the assessment of cannabis use given its potential impact on clinical care. In this review, the authors provide an understanding of nomenclature and tools to assess cannabis use, highlight essential components to guide clinical policy development and implementation, and discuss the potential impacts of cannabis use on patients' transplant course.

Reexamining "psychosocial clearance": A procedural framework for psychosocial evaluation in liver transplantation

Psychosocial and "nonmedical" phenomena are commonly encountered in liver transplantation (LT) evaluations. They are simultaneously crucial decision-making factors and some of the most difficult and controversial clinical matters clinicians confront. Epidemiology, societal trends, and the preponderance of psychological and behavioral factors underpinning common end-stage liver diseases ensure that LT teams will continue to encounter highly complex psychosocial patient presentations. Psychosocial policies, practices, and opinions vary widely among clinicians and LT centers. Liver clinicians already report insufficient psychosocial expertise, which creates a large gap between the stark need for psychosocial expansion, improvement, and innovation in LT and the lack of accompanying guidance on how to achieve it. While the clinical domains of an LT psychosocial evaluation have been well-described, few articles analyze the procedures by which teams determine candidates' "psychosocial clearance" and no conceptual frameworks exist. This article proposes a framework of core domains of psychosocial evaluation procedures, common pitfalls, and practical improvement strategies.

Management of alcohol-associated liver disease and alcohol use disorder in liver transplant candidates and recipients: Challenges and opportunities

Alcohol-associated liver disease poses a significant global health burden, with rising alcohol consumption and prevalence of alcohol use disorder (AUD) contributing to increased morbidity and mortality. This review examines the challenges and opportunities in the care of candidates and recipients of liver transplant (LT) with AUD. Despite advancements in posttransplant patient survival, the risk of disease recurrence and alcohol relapse remains substantial. Several challenges have been identified, including (1) rising disease burden of alcohol-associated liver disease, variable transplant practices, and systemic barriers; (2) disparities in mental health therapy access and the impact on transplant; (3) variable definitions, underdiagnosis, and stigma affecting access to care; and (4) post-LT relapse, its risk factors, and consequential harm. The review focuses on the opportunities to improve AUD care for candidates and recipients of LT through effective biochemical monitoring, behavioral and pharmacologic approaches, creating Centers of Excellence for post-LT AUD care, advocating for policy reforms, and ensuring insurance coverage for necessary services as essential steps toward improving patient outcomes. The review also highlights unmet needs, such as the scarcity of addiction specialists, and calls for further research on personalized behavioral treatments, digital health, and value-based care models to optimize AUD care in the LT setting.

Clinical Utility and Impact of Phosphatidylethanol Testing in Liver Transplantation Evaluations

BACKGROUND

Phosphatidylethanol (PEth) is a serum biomarker that can detect alcohol use within the last 28 days with excellent sensitivity and specificity. Urinary ethyl glucuronide (uEtG) is commonly used in transplant settings to screen for alcohol use; however, it has several limitations relevant to liver transplantation. Transplant centers are beginning to regularly utilize PEth as part of the screening process for high-risk liver transplantation candidates although the clinical utility of uniform pre-transplant PEth testing is unclear.

METHODS

This was a retrospective chart review of all patients evaluated for liver transplantation from December 1, 2019, through May 31, 2022, at a large academic tertiary referral center utilizing uniform serum PEth and uEtG screening. Information regarding the patients' transplantation status, age, sex, race, Model for End-Stage Liver Disease score, and PEth levels was obtained. In those with a positive PEth, we examined if the result would have been detected with uEtG, identified a discrepancy from the documented patient report of last use, led to a change in the Psychosocial Assessment of Candidate for Transplantation score, or influenced the transplant selection committee's decision.

RESULTS

Our sample included 865 individuals (mean age = 55.20, 61.27% male and 82.54% white) with calculated Model for End-Stage Liver Disease-Sodium scores ranging from 6.43 to 50.65 (mean: 18.09; median: 16.46). Forty-eight patients were found to have a positive PEth (PEth range 20-1833); 75% of the sample had alcohol-associated liver disease. In 23 of 48 (47.91%) cases, the positive PEth identified alcohol use missed by a concomitant uEtG screen. A positive PEth test identified a discrepancy from patients' self-report in 29 (60.42%) cases and influenced the selection committee's decision in 28 cases (58.33%).

CONCLUSION

Uniform pretransplant PEth screening of liver transplant candidates at the time of initial evaluation identified alcohol use that would have been missed by uEtG testing, identified discrepancies from the patient's self-report, and influenced clinical decision-making in a significant number of cases. These findings support the use of uniform PEth screening in liver transplantation evaluations.

Assessment and Evaluation of Alcohol Use Disorder in Liver Transplant

Alcohol-related liver disease is the most common indication for liver transplantation. It is essential for providers in transplantation to be informed of the state of the science in evaluation of alcohol use disorder (AUD). This review examines the broad range of approaches to the evaluation of AUD ranging from traditional interview approaches to recent literature on artificial intelligence models. The empirical support for methods of evaluation is examined. The authors discuss the use of each method in the context of patients seeking a liver transplant for alcohol-related liver disease. This review emphasizes the importance of using objective assessments so that transplant centers make evidence-based decisions and reduce cognitive bias. The review concludes with a proposed assessment battery for evaluation and bridges to future directions in the field of AUD assessment in liver transplantation.

"But I didn't drink!": What to do with discordant phosphatidylethanol results

Liver transplantation (LT) teams must be adept at detecting, evaluating, and treating patients' alcohol use, given its prominence among psychological and behavioral phenomena which cause and contribute to liver diseases. Phosphatidylethanol (PEth) is a highly useful alcohol biomarker increasingly recommended for routine use in hepatology and LT. PEth is unique among alcohol biomarkers because of its wide detection window, high sensitivity and specificity, and the correlation of its numerical value with different patterns of alcohol use. Alongside myriad clinical opportunities in hepatology and LT, PEth also confers numerous challenges: little guidance exists about its clinical use; fearing loss of LT access and the reactions of their clinicians and families, candidates and recipients are incentivized to conceal their alcohol use; and liver clinicians report lack of expertise diagnosing and treating substance-related challenges. Discordance between patient self-reported alcohol use and toxicology is yet another common and particularly difficult circumstance. This article discusses the general toxicological properties of PEth; explores possible scenarios of concordance and discordance among PEth results, patient history, and self-reported drinking; and provides detailed clinical communication strategies to explore discordance with liver patients, a key aspect of its use.

Factors associated with a positive phosphatidylethanol test during liver transplantation evaluation

BACKGROUND

Early identification of alcohol use is crucial for informing recommendations of appropriate follow-up treatment pre-liver transplant and optimizing post-liver transplant outcomes. The purpose of the study was to investigate whether there are psychosocial factors associated with a positive PEth test.

METHODS

All patients who underwent a routine pre-surgical psychological evaluation for liver transplant listing (all etiologies, including acute liver failure, dual organ, and re-transplantation) at a single health care system in 2020 were included in a retrospective chart review. Data extraction included results from PEth testing and information from the psychological evaluation (i.e., demographic, psychiatric symptoms, and cognitive functioning).

RESULTS

There were 158 patients (73.8%) who had a PEth test, of whom 21.5% had a positive result (n = 34). Younger age was associated with a positive PEth (p < .001). ALD status and type of ALD (hepatitis vs. cirrhosis) were also associated with a positive PEth test. Other demographic characteristics and psychiatric symptoms were not associated with a positive PEth result (p > .05).

CONCLUSION

Younger age was the only significant demographic variable associated with a positive PEth test. Given the difficulty of predicting who may be using alcohol, it may be useful to use PEth testing for all patients during the pre-liver transplant evaluation and while patients are listed for liver transplant. Early identification of alcohol use through routine PEth testing will help identify patients who are using alcohol and need further treatment for alcohol use to optimize health and post-transplant outcomes.

New insights into the molecular basis of alcohol abstinence and relapse in alcohol-associated liver disease

Alcohol use disorder remains a significant public health concern, affecting around 5% of adults worldwide. Novel pathways of damage have been described during the last years, providing insight into the mechanism of injury due to alcohol misuse beyond the direct effect of ethanol byproducts on the liver parenchyma and neurobehavioral mechanisms. Thus, the gut-liver-brain axis and immune system involvement could be therapeutic targets for alcohol use disorder. In particular, changes in gut microbiota composition and function, and bile acid homeostasis, have been shown with alcohol consumption and cessation. Alcohol can also directly disrupt intestinal and blood-brain barriers. Activation of the immune system can be triggered by intestinal barrier dysfunction and translocation of bacteria, pathogen-associated molecular patterns (such as lipopolysaccharide), cytokines, and damage-associated molecular patterns. These factors, in turn, promote liver and brain inflammation and the progression of liver fibrosis. Other involved mechanisms include oxidative stress, apoptosis, autophagy, and the release of extracellular vesicles and miRNA from hepatocytes. Potential therapeutic targets include gut microbiota (probiotics and fecal microbiota transplantation), neuroinflammatory pathways, as well as neuroendocrine pathways, for example, the ghrelin system (ghrelin receptor blockade), incretin mimetics (glucagon-like peptide-1 analogs), and the mineralocorticoid receptor system (spironolactone). In addition, support with psychological and behavioral treatments is essential to address the multiple dimensions of alcohol use disorder. In the future, a personalized approach considering these novel targets can contribute to significantly decreasing the alcohol-associated burden of disease.