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HelpTest Code ETGR Ethyl Glucuronide Screen with Reflex, Random, Urine
Ordering Guidance
For situations where chain of custody is required, a Chain of Custody Kit (T282) is available. For chain-of-custody testing, order ETGX / Ethyl Glucuronide Confirmation, Chain of Custody, Random, Urine.
Additional Testing Requirements
If urine creatinine is required or adulteration of the sample is suspected, the following test should also be ordered, ADULT / Adulterants Survey, Random, Urine.
Specimen Required
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube: Plastic urine container
Submission Container/Tube: Plastic, 5 mL tube
Specimen Volume: 5 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Useful For
Screening and confirmation for drug abuse involving alcohol
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| ETGS | Ethyl Glucuronide Screen, U | Yes | Yes |
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| ETGC | Ethyl Glucuronide Confirmation, U | Yes | No |
Testing Algorithm
Testing begins with a screening assay. If the screen is positive, then the liquid chromatography tandem mass spectrometry confirmation with quantification will be performed at an additional charge.
Method Name
Immunoassay
Reporting Name
Ethyl Glucuronide Scrn w/Reflex, USpecimen Type
UrineSpecimen Minimum Volume
2.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Refrigerated (preferred) | 28 days | |
| Frozen | 28 days | ||
| Ambient | 72 hours |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Clinical Information
Ethyl glucuronide is a direct metabolite of ethanol that is formed by enzymatic conjugation of ethanol with glucuronic acid. Alcohol in urine is normally detected for only a few hours, whereas ethyl glucuronide can be detected in the urine for 1 to 3 days.
This procedure uses immunoassay reagents that are designed to produce a negative result when no drugs are present in a natural (ie, unadulterated) specimen of urine; the assay is designed to have a high true-negative rate. Like all immunoassays, it can have false-positives due to cross-reactivity with natural chemicals and drugs other than those they were designed to detect. The immunoassay can also have false negatives due to the antibody's ability to cross react with different drugs in the class being screened. When the screen result is positive, liquid chromatography tandem mass spectrometry will be performed to confirm the result.
Reference Values
Negative
Screening cutoff concentration: 500 ng/mL
Interpretation
If the screen result is negative, ethyl glucuronide concentrations were not detected.
If the screen result is positive, then confirmation by liquid chromatography tandem mass spectrometry will be performed.
A positive interpretation will be given if either the ethyl glucuronide (EtG) result is greater than or equal to 250 ng/mL and/or the ethyl sulfate (EtS) is greater than or equal to 100 ng/mL.
A "high" positive (ie, >1000 ng/mL) may indicate:
-Heavy drinking on the same day or previously (ie, previous day or 2).
-Light drinking the same day
A "low" positive (ie, 500-1000 ng/mL) may indicate:
-Previous heavy drinking (ie, previous 1 3 days).
-Recent light drinking (ie, past 24 hours).
-Recent intense "extraneous" exposure (ie, within 24 hours or less).
A "very low" positive (ie, 100-500 ng/mL) may indicate:
-Previous heavy drinking (ie, 1-3 days)
-Previous light drinking (ie, 12-36 hours).
-Recent "extraneous" exposure.(2)
Cautions
Care should be taken when interpreting results since there are many factors (eg, fluid intake and other biologic factors) that may influence a urine test result. It is possible that substances other than those investigated in the specificity study may interfere with the test and cause false-positive or negative results.
Method Description
This assay is a homogeneous enzyme immunoassay technique. The assay will be performed semi-quantitatively. The assay is based on competition between free drug in the urine sample, and a drug labeled with the enzyme glucose-6-phosphate dehydrogenase for a fixed amount of specific antibody binding sites. Active enzyme converts nicotinamide adenine dinucleotide (NAD+) to NADH, which results in an absorbance change that can be measured spectrophotometrically at 340 nm.(Package insert: DRI Ethyl Glucuronide Assay. Microgenics Corporation; 09/2015)
Day(s) Performed
Monday through Saturday
Report Available
Same day/1 to 2 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80307
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| ETGR | Ethyl Glucuronide Scrn w/Reflex, U | 58375-7 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 63420 | Ethyl Glucuronide Screen, U | 58375-7 |