From the Guidelines
Laboratory tests for individuals with alcohol use disorder should include comprehensive metabolic panel (CMP), complete blood count (CBC), liver function tests (AST, ALT, GGT, bilirubin, albumin), coagulation studies (PT/INR), lipid panel, magnesium, phosphate, and vitamin B1 (thiamine) levels, as recommended by recent guidelines 1. These tests are crucial because alcohol affects multiple organ systems, particularly the liver, and can cause nutritional deficiencies, electrolyte imbalances, and hematologic abnormalities like macrocytic anemia. Some key points to consider when ordering laboratory tests for individuals with alcohol use disorder include:
- Elevated liver enzymes, especially GGT and AST:ALT ratio >2:1, often indicate alcohol-related liver damage 1.
- Thiamine levels are important as deficiency can lead to Wernicke-Korsakoff syndrome.
- Regular monitoring of these parameters helps track disease progression, guides treatment decisions, and monitors for complications of alcohol use disorder. Additional important tests include:
- Blood alcohol concentration
- Urine toxicology screen
- Carbohydrate-deficient transferrin (CDT) which is specific for chronic alcohol use Depending on clinical presentation, consider testing for:
- Hepatitis B and C
- HIV
- Obtaining an ECG to assess for cardiac abnormalities, as suggested by recent studies 1. It is also important to use screening tools such as AUDIT to identify individuals with alcohol use disorder and to monitor their response to treatment 1. The use of alcohol biomarkers, such as phosphatidylethanol (PEth), ethyl glucuronide (EtG), and ethyl sulphate (EtS), can also be helpful in assessing alcohol use and monitoring treatment response 1.
From the Research
Laboratory Tests for Alcohol Use Disorder
The following laboratory tests are commonly used to assess individuals with alcohol use disorder:
- γ-glutamyltransferase (GGT) activity 2, 3, 4
- Aspartate aminotransferase (AST) activity 2, 3
- Alanine aminotransferase (ALAT) 3, 4
- High-density lipoprotein cholesterol (HDL-C) content of serum 2
- Erythrocyte mean corpuscular volume (MCV) 2, 4
- Carbohydrate deficient transferrin 2
- β-hexosaminidase 2
- Acetaldehyde adducts 2
- Urinary ratio of serotonin metabolites, 5-hydroxytryptophol and 5-hydroxyindoleacetic acid 2
Liver Function Tests
Liver function tests, such as SGOT, SGPT, Alkaline phosphatase, and GGTP, may be elevated in individuals with alcohol use disorder, but their predictive value is limited 5. The ASAT/ALAT ratio and the ratio of GGT to alkaline phosphatase may be useful in distinguishing between alcoholic and non-alcoholic liver injury 3.
Screening and Recognition of Alcohol Abuse
No single laboratory test or combination of tests is suitable for screening for alcohol abuse in primary care patients 4. However, elevated laboratory test values, such as GGT, may be used as an "alerting factor" for problem drinking, and may be a powerful patient-motivating factor in monitoring treatment response 4.