Phosphatidylethanol (PEth)

Label Mnemonic:	PETH
Epic code:	LAB8734
Downtime form:	A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Commercial Mailout Laboratory
6240-8 RCP
356-8593

Specimen(s):

Whole Blood

Collection Medium:

Lavender top tube 3 mL (EDTA)

Minimum:

Preferred Minimum: 1 mL whole blood in EDTA lavender top tube
Absolute Minimum: 0.5 mL whole blood in EDTA lavender top tube

Rejection Criteria:

Gel separator tubes, Plain Red, light blue (citrate), or yellow (SPS or ACD solution).

Delivery Instructions:

IMMEDIATELY place tube in ice and delivery to the laboratory.

Testing Schedule:

Varies

Turn Around Time:

1-4 days upon receipt at reference laboratory

Reference Range:

By report

Interpretive Data:

Phosphatidylethanol
(PEth) homologues  Result Interpretation                             
PEth 16:0/18.1     Less than 10 ng/mL   Not detected
(POPEth)           Less than 20 ng/mL   Abstinence or light alcohol
                                        consumption
                   20 – 200 ng/mL       Moderate alcohol consumption
                   > 200 ng/mL          Heavy alcohol consumption or 
                                        chronic alcohol use
---------------------------------------------------------------------
PEth 16:0/18.2                          Reference ranges are not well
(PLPEth)                                established
(Reference: W. Ulwelling and K Smith 2018 J. Forensic Sci)

Phosphatidylethanol (PEth) is a group of phospholipids formed in the presence of ethanol, phospholipase D and phosphatidylcholine. PEth is known to be a direct alcohol biomarker. The predominant PEth homologues are PEth 16:0/18:1 (POPEth) and PEth 16:0/18:2 (PLPEth), which account for 37-46% and 26-28% of the total PEth homologues, respectively. PEth is incorporated into the phospholipid membrane of red blood cells and has a general half-life of 4 - 10 days and a window of detection of 2 - 4 weeks. However, the window of detection is longer in individuals who chronically or excessively consume alcohol. Serial monitoring of PEth may be helpful in monitoring alcohol abstinence over time. PEth results should be interpreted in the context of the patient's clinical and behavioral history. Patients with advanced liver disease may have falsely elevated PEth concentrations (Nguyen VL et al 2018, Alcoholism Clinical & Experimental Research).

Comments:

Ordering Recommendation
Biomarker associated with ethanol consumption; may be helpful in monitoring alcohol abstinence.

Methodology:

Quantitative Liquid Chromatography/Tandem Mass Spectrometry

CPT Code:

80321

See Additional Information:
Specimens Requiring Immediate Delivery