Drug reaction with eosinophilia and systemic symptoms (DRESS) et human herpesvirus 6 (HHV-6)

Drug reaction with eosinophilia and systemic symptoms (DRESS) may be life-threatening related due to visceral involvement. A limited number of drugs may induce DRESS. DRESS pathophysiology is unique and associates reactivation of herpesviruses (HHV), including mainly HHV-6, but also HHV-7, or cytomegalovirus, as a consequence of drug intake. Immune reaction against viral antigens is the key factor responsible for visceral manifestations. A multifactorial genetic susceptibility is probably necessary. It includes combination of HLA at risk with specific drug intake and genetic polymorphism of genes playing a role in drug metabolism. It has been recently demonstrated that HHV-6 may integrate cellular DNA. In some persons, inherited chromosomal HHV-6 integration is observed defined by the presence of HHV-6 genome in every cell and results in the germ-line transmission of the HHV-6 genome. This condition could genetically predispose to HHV-6 reactivation.