Association of pityriasis rosea with Human Herpesvirus-6

Background: pityriasis rosea (pr) is a common papulosquamous skin disorder that is suspected to have an infectious etiology. we aimed to study the role of human herpesvirus-6 (hhv-6) in the pathogenesis of pr. method: we used immunohistochemical (ihc) assays to detect hhv-6 in patients with pr. fifty-one patients with pr and 35 age and sex matched healthy control samples were enrolled in the study. the intensity and percentage of cell staining for hhv-6 infection were evaluated and recorded. result: the intensity of ihc staining was negative in 25 (49.01%) patients and 24 (68.58%) control samples while it was +1 in 6(11.77%) patients and 11 (31.42%) control samples, +2 in 4 (7.85%) patients and +3 in 16 (31.37%) of them. the incidence of moderate and intense staining for hhv-6 was significantly higher among patients with pr than the control group (p value < 0.01). conclusion: we concluded that hhv-6 infection may play a role in some patients with pr. the rate of hhv-6 infection was significantly higher in pr patients than the control group.