RESUMEN
A previously healthy 11-year-old Caucasian boy presented with a 2-week history of nonspecific symptoms of nausea and nonbilious, nonbloody emesis. He developed significant jaundice and hepatic encephalopathy within 1 week of beginning symptoms and was discovered to have fulminant liver failure. Extensive work-ups for underlying etiologies included serologic evaluation for underlying chronic liver diseases, toxicology screening, inborn errors of metabolism, and infectious diseases. The results of the entire assessment were negative except for human herpesvirus 6B, which was detected in the liver by quantitative real-time polymerase chain reaction and immunohistochemical analysis. The patient underwent ABO-compatible liver transplantation and has had clinically stable health, with no evidence to date of complications associated with HHV-6 or other members of the herpesvirus family.