What is the role of phosphatidyl ethanol (PEth) in treating alcohol use disorder and liver disease?

From the Guidelines

Phosphatidyl ethanol (PEth) is not a treatment for alcohol use disorder or liver disease, but rather a biomarker used to detect and monitor alcohol consumption. PEth is formed in red blood cell membranes when alcohol is consumed, through a reaction between phosphatidylcholine and ethanol. Unlike traditional alcohol biomarkers such as gamma-glutamyl transferase (GGT) or carbohydrate-deficient transferrin (CDT), PEth is highly specific to alcohol consumption and can detect drinking for up to 2-4 weeks after consumption, as noted in recent clinical guidelines 1. This makes it valuable in clinical settings for objectively assessing alcohol intake, monitoring abstinence in treatment programs, and evaluating treatment effectiveness. For patients with liver disease, PEth testing helps healthcare providers determine if ongoing alcohol use is contributing to liver damage, as continued drinking can significantly worsen conditions like alcoholic hepatitis or cirrhosis. The test requires a blood sample and is increasingly available in clinical settings, though it's essential to understand that PEth itself has no therapeutic properties - its value lies in improving diagnosis and monitoring of alcohol-related conditions.

Some key points to consider when using PEth in clinical practice include:

• The importance of comprehensive history of alcohol use, including recent and lifetime alcohol intake, as emphasized by an expert panel on alcohol-related liver disease 1.
• The challenges in quantifying alcohol use, such as underreporting, stigma, impaired recall, and cognitive impairment, which can be addressed by using standardized surveys, electronic health records, and input from collateral sources 1.
• The role of PEth in differentiating between alcohol-related liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD), as part of an integrated approach to managing MetALD 1.
• The recommendation to use alcohol biomarkers, such as PEth, to aid in diagnosis and support recovery, as stated in the 2019 practice guidance from the American Association for the Study of Liver Diseases 1.

Overall, PEth is a valuable tool in the diagnosis and monitoring of alcohol-related conditions, and its use can contribute to improved patient outcomes in the context of alcohol use disorder and liver disease.

From the Research

Role of Phosphatidyl Ethanol (PEth) in Treating Alcohol Use Disorder and Liver Disease

• Phosphatidyl ethanol (PEth) is a direct nonoxidative metabolite of ethanol that may be measured in clinical samples as a marker for monitoring alcohol consumption 2.
• PEth testing is becoming increasingly common as a tool to assess for alcohol consumption in the practice of addiction medicine, with its potential to be an objective measure of ethanol exposure 3.
• The use of PEth testing in identifying alcohol intake in liver disease patients has been limited, but it has been used in a wide variety of clinical and nonclinical settings 2.

Applications of PEth Testing

• PEth detects moderate-to-heavy alcohol use in liver transplant recipients, with 70% of those who reported no alcohol use having consistently negative PEth levels (<8 ng/ml) 4.
• PEth testing can enable early identification of patients at risk of alcohol use and facilitate abstinence in patients with a history of alcohol dependence and alcohol-related liver damage 4.
• However, PEth results can be influenced by medical procedures and events such as blood transfusion, which can lead to false-positive results 3.

Challenges and Limitations

• The field has yet to develop a complete understanding of the factors that can influence a PEth level, including the impact of medical procedures and events 3.
• Further study is needed to understand how PEth is impacted by these factors if we are to maintain a just and ethical practice in the setting of addiction and transplant medicine 3.
• The use of PEth testing in patients with advanced liver disease has not been extensively studied, and more research is needed to determine its effectiveness in this population 5.