Phosphatidylethanol clearance after packed red blood cell transfusion

Area of Science:

• Clinical Chemistry
• Transfusion Medicine
• Toxicology

Background:

• Phosphatidylethanol (PEth) is a biomarker for long-term alcohol consumption.
• PEth is crucial for assessing abstinence, particularly in transplant candidates.
• Packed red blood cell (pRBC) transfusions can introduce exogenous PEth, potentially confounding results.

Purpose of the Study:

• To evaluate the kinetics and duration of PEth 16:0/18:1 positivity following pRBC transfusion.
• To determine the impact of pRBC transfusion on PEth levels in recipients.

Main Methods:

• Liver transplant recipients (n=76) receiving pRBCs were monitored for PEth 16:0/18:1 concentrations up to two weeks post-transfusion.
• PEth clearance kinetics were analyzed, with adjustments for hemoglobin and hematocrit.

Main Results:

• Nearly half (48.7%) of recipients showed PEth ≥ 10 ng/mL post-transfusion.
• PEth half-life was variable (mean 6.6 days), improved with hematocrit/hemoglobin correction (mean 4.6-4.9 days).
• Clearance to <10 ng/mL ranged from <1 to >19 days; 40.5% cleared within 5 days.

Conclusions:

• PEth positivity post-pRBC transfusion is more frequent than previously assumed.
• Higher PEth thresholds (e.g., 20 ng/mL) are advisable for interpretation.
• Transplant teams must cautiously interpret PEth for 2-3 weeks post-transfusion due to potential pRBC influence.