Persistent Urinary Ethyl Sulfate in the Absence of Urinary Ethyl Glucuronide in a Patient with Alcohol Use Disorder Who Claimed Abstinence.

A 48-year-old nurse with an alcohol use disorder history was being monitored in a professional health program. She consistently produced low-to-moderate urinary ethyl sulfate (EtS) concentrations in the absence of detectable urinary ethyl glucuronide (EtG), blood phosphatidylethanol and breath alcohol. She denied intentional ethanol consumption. After prolonged monitoring in a drug treatment program, including a period in a controlled environment, we concluded that this individual's urinary EtS likely resulted from anatomical and microbial factors related to Roux-en-Y gastric bypass surgery, with possible contributions from hidden dietary sources of ethanol. We have no definitive explanation for the lack of urinary EtG.