Adduct Dipstick for Diagnosis of Acetaminophen Toxicity

This study is a non-intervention, clinical study to test "research use only" APAP protein
adducts dipsticks in human blood samples. The study will be conducted in two phases. In
phase 1, the research use only dipsticks and dipstick testing components will be tested for
feasibility in the emergency department at UAMS. Patients will be enrolled that are having
an acetaminophen level obtained as part of their medical evaluation. In phase 2, the
research use only dipsticks will be tested in centers that participate in the Acute Liver
Failure Study Group (ALFSG), a clinical research network funded by the National Institutes
of Diabetes, Digestive and Kidney Diseases (NIDDK). Subjects participating in the clinical
registry of the ALFSG will be approached for enrollment. These patients all have the
diagnosis of acute liver failure or acute liver injury from a variety of etiologies,
including APAP. A single blood sample will be obtained and will be aliquoted for 1) testing
by the dipstick and 2) testing by high performance liquid chromatography with
electrochemical detection (HPLC-EC) analysis for APAP protein adducts. APAP levels will also
be determined from the second aliquot of blood. In both Phase 1 and Phase 2, the dipsticks
will be read manually and by dipstick readers by independent testers that are not directly
involved in the clinical care of the patients. The results of the two dipstick readings will
be recorded, will remain confidential and will not be used in the diagnosis or management of
the patient. The results of the dipsticks and HPLC-EC assays will be compared to the final
patient diagnoses.