AKT-3188

A 35-year-old woman presents to her GP with a complaint of feeling constantly fatigued for the past 3 months. She has a history of intravenous drug use and routine testing reveals abnormal liver enzyme tests, including a significant increase in alanine aminotransferase (ALT). Although she is not jaundiced, the GP suspects that she may be suffering from acute hepatitis. Which of the following tests is most likely to be positive in this patient if this suspicion is correct?