Human herpesvirus 6–related fulminant myocarditis and hepatitis in an immunocompetent adult with fatal outcome

SummaryA 59-year-old previously healthy man had flulike symptoms of fever and diarrhea for a week, which worsened despite treatment with antibiotics. After admission, his medical condition rapidly deteriorated with renal failure, heart failure, and a marked increase of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase. The patient died of a cardiac arrhythmia 3 days after the admission. The autopsy showed diffuse myocarditis with a granulocytic and monocytic infiltrate, necrotizing arteritis of the coronary arteries, and fulminant hepatitis, with microvesicular steatosis and necrosis. Cell-free serum showed high copies of human herpesvirus 6 B variant DNA by polymerase chain reaction. Human herpesvirus 6 B was identified in the heart, liver, lung, and spleen by immunohistochemistry. No parvovirus B19 was evident in the heart by immunohistochemistry. Human herpesvirus 6 is increasingly found in association with myocarditis in immunocompromised patients; however, histopathologic features and the clinical severity of this disease have not yet been clearly defined. Only 4 to 5 cases of human herpesvirus 6 fulminant myocarditis have been reported, all in young children or immunosuppressed patients. To the best of our knowledge, this is the first case in the English literature of human herpesvirus 6 fulminant myocarditis and hepatitis in an immunocompetent adult with a fatal outcome. In addition, several pathologic features of our case have not been previously reported.