Association of human herpesvirus 6 infection with drug reaction with eosinophilia and systemic symptoms

Background: There is a current debate regarding the association of human he rpesvirus 6 (HHV-6) infection and drug reaction with eosinophilia and syste mic symptoms (DRESS). Methods: Seven consecutive patients hospitalized with DRESS were enrolled i n a prospective study to evaluate evidence of active HHV-6 infection. Observations: The imputable drugs were carbamazepine (5 patients), ibuprofe n (1 patient), and sulfasalazine (1 patient). All patients were seropositiv e for anti-HHVd IgG antibodies. Anti-HHV-6 IgM antibodies were detected in 4 of the 7 patients with a seroconversion in 2 patients. Neither anti-cytom egalovirus nor anti-Epstein-Barr virus early antigen IgM antibody was detec ted. Human herpesvirus 6 genome was not detected by polymerase chain reacti on in the first serum sample of all patients. It was weakly detected in ski n lesions in the last patient tested by polymerase chain reaction but was n ot found in uninvolved skin. Conclusions: The results suggest an association between HHV-6 active infect ion (primo-infection or reactivation) and severe DRESS. Absence of anticyto megalovirus or anti-Epstein-Barr virus early antigen IgM antibodies argues against a nonspecific viral reactivation. Human herpesvirus 6 infection may play a role in the development of DRESS in susceptible patients. Some drug s with reactive metabolites could favor reactivation and propagation of HHV -6.