Alcohol Abuse


Indications for Testing

  • Suspicion of alcohol abuse – patient meets World Health Organization (WHO) criteria for diagnosis from the International Classification of Diseases 10th Revision (ICD-10) and the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5)
  • Trauma-related injury
  • Monitoring of patient in substance abuse treatment
  • Follow-up testing to investigate abnormalities of other biomarkers suggestive of alcohol abuse
    • Gamma glutamyl transferase (GGT)
    • Mean corpuscular volume (MCV)
    • High-density lipoprotein (HDL) cholesterol
    • Aspartate aminotransferase (AST)
    • Alanine aminotransferase (ALT)

Criteria for Diagnosis

  • ICD-10 criteria for diagnosis of alcoholism
    • ICD-10 defines 1 unit of alcohol equal to 8-10 g
      • 8 oz of beer, 5 oz of wine, 1 oz of hard liquor
  • CDC – patterns of alcohol consumption
    • Binge drinking
      • Women – ≥4 drinks on a single occasion
      • Men – ≥5 drinks on a single occasion
    • Heavy drinking
      • Women – >1 drink/day on average
      • Men – >2 drinks/day on average
  • DSM-5 criteria for alcohol dependency
    • Three or more of the following for ≥1 month or repeatedly over the past 12 months
      • Strong desire or compulsion to drink
      • Difficulty in controlling drinking in terms of onset, termination, or extent of use
      • Physiologic withdrawal when use is reduced – tremor, sweating, tachycardia, anxiety, insomnia
      • Drinking to avoid withdrawal state
      • Evidence of alcohol tolerance – increasing amount required to produce same effects
      • Progressive neglect of other interests
      • Persistent use despite awareness of harmful effects

Laboratory Testing

  • Nonspecific testing
    • CBC
      • MCV
        • May show macrocytosis
        • More sensitive test in females – not specific for alcohol abuse
        • Limited as a screening test – reduced sensitivity with B12 and folate deficiencies, liver disease, concomitant tobacco abuse, and hypothyroidism
        • Not a suitable marker for following abstinence – normalization of MCV may require 2-4 months of abstinence
      • Platelet count – thrombocytopenia present in ~30% of alcohol-abuse patients
        • Rapidly normalizes with abstinence
      • HDL – increases with regular consumption of 3-5 drinks per day
        • Decreases within 1-2 weeks of abstinence
      • Ferritin – increases with low levels of alcohol consumption
      • Albumin  – low in association with chronic alcoholic liver disease
        • Urate – increases with low levels of alcohol consumption
        • Immunoglobulin A – increased in chronic alcoholic liver disease
    • Liver function tests
      • Aspartate transaminase (AST) and alanine transaminase (ALT)
        • AST:ALT ratio – >2 suggests alcoholic etiology
        • May not be elevated – not highly sensitive or specific
        • ALT is fairly specific for liver injury, although AST may also be elevated with skeletal muscle and cardiac muscle injury
      • Gamma glutamyl transferase (GGT)
        • Sensitive and inexpensive indirect marker of alcohol consumption
        • Nonspecificity for alcohol abuse limits usefulness – may also be elevated with nonalcoholic fatty liver disease, drug intoxication, obesity, diabetes, hepatobiliary disorders
        • Even moderate drinkers (<60 g/week), especially men, show higher levels than abstainers
        • May be a less-sensitive marker in young drinkers
        • Age dependent – levels increase with age, even in abstinent patients
        • Normalization requires 2-3 weeks of abstinence
  • Ethanol levels – blood, urine, or breath specimens
    • Use for patients with suspected acute alcohol consumption
    • Suggestive of dependence
      • Levels >0.15 g/dL (>1.5%) without evidence of intoxication
      • >3.0 g/dL (>3.0%) without death
      • Positive level during daytime hours
  • Carbohydrate deficient transferrin (CDT)
    • Can detect ≥40 g/day ethanol consumption for ≥2 weeks
      • Estimates alcohol consumption over the past month
    • ≥1.6% – considered elevated and associated with active alcohol use
      • Levels between 1.4-1.6% should be retested in 3-4 weeks
    • Sensitivity
      • Moderately sensitive and specific for longer-term alcohol use
      • More sensitive test in men – especially >40 years of age
      • May be a sensitive marker of relapse in chronic abusers
      • Highest sensitivity may be achieved in combination with one or all of the following
        • GGT
        • MCV
        • Ethyl glucuronide
  • Ethyl glucuronide
    • Detects recent ethanol exposure – 1-4 days post ingestion
      • Ethanol dose may be as low as ≤0.25 g/kg at day 1 testing or ≤0.5 g/kg at day 2 testing
      • Aids in monitoring alcohol abstinence – negative test confirms abstinence during ~2 previous days
    • Specimens
      • Urine – most available testing with quantitation
      • Hair – may be better indicator of long-term alcohol consumption
    • False-positive results
      • May reflect use of ethanol-containing personal care products (eg, cough syrup, mouth wash, hand sanitizer)
      • Urine specimen with high glucose level from diabetics
      • Storage of specimen >12 hours

Differential Diagnosis


  • Ethanol (serum, breath, or urine) – best screen for acute alcohol ingestion


  • Ethyl glucuronide (EtG)/ethyl sulfate (EtS) – may be used to monitor short-term abstinence (up to 80 hours)
  • Carbohydrate deficient transferrin (CDT) – may be used to monitor longer abstinence (2-5 weeks)
  • Phosphatidylethanol (PEth) – may be used to monitor longer abstinence (up to 4 weeks)

Clinical Background

Approximately 20% of primary care patients in the U.S. drink alcohol (ethanol) at levels harmful to health.


  • Incidence – 20-30% of hospital admissions and health-care costs are due to alcohol abuse
  • Age – usually young adults
  • Sex – M>F


  • Alcohol consumption has toxic effects on the liver and the hematologic system
    • Liver enzymes are induced by alcohol and may increase during the ensuing hepatocyte injury
    • Suppresses albumin production by the liver
    • Toxic to the hematologic precursor cells and may affect red blood cell morphology
  • Markers of ethanol exposure

    Markers of Ethanol Exposure


    Ethyl glucuronide (EtG)

    Ethyl sulfate (EtS)

    Carbohydrate-deficient transferrin (CDT)

    Phosphatidylethanol (PEth)

    Metabolite of ethanol

    Direct minor metabolite (<0.1% of ethanol disposition)


    Heavy ethanol abuse increases fractions of CDT

    Direct ethanol metabolite





    Marker for abstinence

    Short term abstinence

    Long term marker of heavy ethanol use

    Long term marker of heavy ethanol use

    Length of time since exposure

    Up to 80 hrs

    Detectable for

    • 1 day after consumption of ethanol <25 mg/kg
    • 2 days after consumption of ethanol <50 mg/kg

    2-5 wks

    Consumption of 50-80 g ethanol/per day for 1-2 weeks elevates CDT above baseline

    Up to 4 wks

    Influences upon sensitivity

    Amount of ethanol consumed

    • Sensitivity highest in heavy drinkers

    Cutoff points

    False positive from ethanol OTC products (eg, mouthwash)

    Intervals based on methodology

    Rare congenital disorders will have elevated values

    Amount of ethanol consumed over last 7 days (most PEth resides in red blood cell membranes)

    Effect of cirrhosis




Clinical Presentation

  • May present with signs of acute intoxication – slurred speech, altered sense of consciousness, coma
  • Other nonspecific signs in non-intoxicated patients – depression, anxiety
  • Complications
    • Withdrawal signs and symptoms – tremor, tachycardia, nausea, anxiety, sweating, insomnia
      • Delirium tremens – clouding of consciousness, psychomotor agitation, fear, delusions, hallucinations
    • Wernicke-Korsakoff syndrome – caused by alcohol-induced thiamine deficiency
    • Impaired cognition and learning, confabulation, ataxia, nystagmus
    • Cirrhosis
    • Pancreatitis
    • Esophageal varices
    • Coagulopathy – vitamin K deficiency
    • Ascites
    • Megaloblastic anemia – vitamin B12 and folate deficiency

Indications for Laboratory Testing

  • Tests generally appear in the order most useful for common clinical situations
  • Click on number for test-specific information in the ARUP Laboratory Test Directory
Test Name and Number Recommended Use Limitations Follow Up
Ethanol, Serum or Plasma - Medical 0090120
Method: Quantitative Gas Chromatography/Enzymatic
Serum test to identify acute alcohol ingestion

Assay detection limit – varies based on instrumentation

Alcohols 0090131
Method: Quantitative Gas Chromatography
Use to identify ethanol, methanol, acetone, or isopropanol ingestion

Assay detection limit – 5 mg/dL

Drugs of Abuse Test, Alcohol, Urine - Screen with Reflex to Confirmation/Quantitation 0092280
Method: Semi-Quantitative Alcohol Dehydrogenase/ Qualitative Gas Chromatography-Flame Ionization Detection

Urine screening and confirmation test to identify acute alcohol ingestion

Reflex pattern – if screen is positive, then confirmation by gas chromatography/flame ionization is added

Sensitivity and specificity with urine are relatively poor; not valid for forensic use

Positive cutoff 40 mg/dL

Alcohol, Urine, Quantitative 2010136
Method: Quantitative Gas Chromatography

Useful in the assessment of acute ethanol exposure

Urine ethyl glucuronide screen with reflex to confirmation is preferred for the assessment of ethanol exposure up to several days post-exposure

Sensitivity and specificity with urine are relatively poor; not valid for forensic use

Positive cutoff 5 mg/dL

Carbohydrate Deficient Transferrin for Alcohol Use 0070412
Method: Quantitative Electrophoresis

Identify alcohol abuse or abuse relapse

Will detect chronic ethanol use (≥40 g/day for 2 weeks)

More sensitive in men

Cannot be used in patient suspected of having congenital glycosylation disorders

Advanced liver damage (including severe chronic viral hepatitis) and anti-epileptic drug therapy can increase CDT levels

Ethyl Glucuronide Screen with Reflex to Confirmation, Urine 2007912
Method: Qualitative Enzyme Immunoassay/Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Urine screening and confirmation test to identify acute alcohol ingestion

Cutoff for positive screen – set at 500 ng/mL

Reflex – positive result will be confirmed by liquid chromatography tandem mass spectrometry (LC-MS/MS)

False-positive results –microbial formation or fermentation, ethanol-containing products (eg, hand sanitizer, mouth wash)

False-negative results – bacterial degradation, >4 days since ethanol ingestion

Ethyl Glucuronide and Ethyl Sulfate, Urine, Quantitative 2007909
Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Urine confirmation test to identify acute alcohol ingestion

Analytic range – 100-10,000 ng/mL

Incidental exposure from ethanol containing products may be detected

Phosphatidylethanol (PEth)  2012130
Method: Quantitative Liquid Chromatography/Tandem Mass Spectrometry

Whole blood biomarker associated with ethanol consumption; may be helpful in monitoring alcohol abstinence

Additional Tests Available
Click the plus sign to expand the table of additional tests.
Test Name and NumberComments
CBC with Platelet Count 0040002
Method: Automated Cell Count

Initial test to determine macrocytosis

Hepatic Function Panel 0020416
Method: Quantitative Enzymatic/Quantitative Spectrophotometry

Initial screen for suspected chronic alcohol related hepatic injury

Panel includes albumin, alkaline phosphatase, AST, ALT, direct bilirubin, total protein, and total bilirubin

Gamma Glutamyl Transferase, Serum or Plasma 0020009
Method: Quantitative Enzymatic

May be useful as an indirect marker of alcohol abuse

May be less sensitive marker in young drinkers

Not specific for alcohol abuse; may be elevated with nonalcoholic fatty liver disease, drug intoxication, or other liver diseases

Ethanol, Urine, Qualitative - Medical 0090518
Method: Quantitative Enzymatic

Urine test to identify acute alcohol ingestion

HDL Cholesterol 0020053
Method: Detergent Solubilization/Enzymatic
Albumin, Serum or Plasma by Spectrophotometry 0020030
Method: Quantitative Spectrophotometry
Uric Acid, Urine 0020481
Method: Quantitative Spectrophotometry

Aids in diagnosis of kidney stones; aids in monitoring uric acid levels in patients at risk for kidney stone development (eg, gout)

Immunoglobulin A 0050340
Method: Quantitative Nephelometry

Determine whether to use IgA or IgG tTG and DGP assays

Alkaline Phosphatase, Serum or Plasma 0020005
Method: Quantitative Enzymatic
Bilirubin, Total, Serum or Plasma 0020032
Method: Spectrophotometry
Aspartate Aminotransferase, Serum or Plasma 0020007
Method: Quantitative Enzymatic
Alanine Aminotransferase, Serum or Plasma 0020008
Method: Quantitative Enzymatic
Albumin by Nephelometry 0050671
Method: Quantitative Nephelometry
Ferritin 0070065
Method: Quantitative Chemiluminescent Immunoassay

Aids in the diagnosis of iron deficiency anemia and iron overload; monitor treatment of hemochromatosis