Clinical Utility of Phosphatidylethanol (Peth) Testing in Liver Transplantation Evaluations

Background:

Phosphatidylethanol (PEth) testing allows for evaluation of alcohol consumption for even up to 4 weeks since last ingestion. The utility of PEth in transplant settings to detect continued alcohol use, inform treatment decisions, and determine transplant candidacy is unclear.

Methods

This was a retrospective chart review of all patients evaluated for liver transplantation candidacy at Mayo Clinic, Rochester with PEth testing from December 1, 2019 through May 31, 2022. Information regarding the patients’ transplantation status, age, sex, race, MELD Score, and PEth levels were obtained. In those with a positive PEth, we examined if the result identified a discrepancy from the documented patient report of last use and whether the result influenced a change in clinical decision making, i.e. change in Psychosocial Assessment of Candidate for Transplantation (PACT) score and treatment recommendation.

Results

Our sample included 872 individuals (mean age=54.93±age, 61.24% male and 82.57% Caucasian). Of those, 309 underwent liver transplant, and MELD scores ranged from 6.43-50.65 (Mean 18.53; Median: 16.95). Forty-eight patients were found to have a positive PEth (range 20-1833); 77%, of these individuals had Alcohol-Related Liver Disease. PEth values identified a discrepancy from the patient’s subjective report (last alcohol use) in 60.42% of cases and influenced clinical decision making in 58.33% of cases. PACT scores changed in 24.32% of cases, and Peth results influenced the selection committee decision to defer or deny transplant listing in 56.75% of cases.

Discussion

Of the patients with positive PEths in our study, 77% had Alcohol-Related liver Disease. For those testing positive, clinical decision-making was impacted in 58.33% of the patients. Given organ scarcity and the likelihood of worse outcomes in patients with persistent undisclosed alcohol use, both pre- and post-transplant, Peth testing appears to have significant clinical utility in liver transplant evaluations.

Conclusion

PEth testing influenced decision making in 58.33% of positive cases, thus supporting its clinical utility in Liver Transplantation Evaluations.