Hepatitis E Virus Superinfection: an Underrecognized Trigger of Acute Hepatitis B Virus Flare.

Hepatitis E virus (HEV) infection is a significant cause of acute hepatitis in endemic areas, such as parts of Asia, Africa, and Mexico, though HEV prevalence in the United States has been estimated between 6% and 20%. Chronic hepatitis B virus (HBV) infection affects about 1 per 1.4 million people in North America. Although well documented in Asia, HBV flare secondary to HEV superinfection is rarely reported in the United States. Here, we present a case of chronic undiagnosed HBV infection with acute flare secondary to HEV superinfection.