Human herpesvirus-6 and sudden death in infancy: Report of a case and review of the literature

Investigation of sudden death in infancy is a viral Function of the medical examiner's office. Surveillance of these cases may lead to recognition of new diseases or new manifestations of previously described diseases. Human herpesvirus-6 (HHV-6) is a relatively newly described virus that has been r ecognized as a cause of acute febrile illness in early childhood. While mos t cases are apparently self-limited, seven fatal cases have been reported. We present a case of a seven-month-old Latin American male with recent otit is media and vomiting who was found dead in bed. Autopsy revealed interstit ial pneumonitis with an atypical polymorphous lymphocytic infiltrate in the liver, kidney, heart, spleen, lymph nodes, and bone marrow, associated wit h erythrophagocytosis. Polymerase chain reaction (PCR) analysis of formalin -fixed paraffin-embedded tissue was positive for HHV-6 and negative for Eps tein-Barr virus (EBV) and cytomegalovirus (CMV). HHV-6 was also detected in the atypical lymphoid infiltrate by in-situ hybridization.