Human herpesvirus 6 infection associated with anticonvulsant hypersensitivity syndrome and reactive haemophagocytic syndrome.

Viral infections are thought to play a part in some cutaneous drug reactions. Human herpesvirus 6 (HHV6), which is the agent of exanthema subitum (sixth disease), has never been implicated in a drug reaction. We report a patient with severe phenobarbital-induced anticonvulsant hypersensitivity syndrome in whom a fulminant haemophagocytic syndrome was associated with HHV6 infection. We discuss the possible role of HHV6 in this reactive condition.