Human herpesvirus 7 in patients with pityriasis rosea. Electron microscopy investigations and polymerase chain reaction in mononuclear cells, plasma and skin.

Background: Clinical evidence suggests a viral etiology for pityriasis rosea (PR).

Objective: To evaluate human herpesvirus (HHV)-6 and HHV-7 as candidates for the etiology of PR.

Methods: Blood and skin tissue from 12 patients with acute PR, and 12 patients with other dermatoses were studied, as well as blood samples from 25 healthy persons.