Association of pityriasis rosea with Human Herpesvirus-6

Background: Pityriasis rosea (PR) is a common papulosquamousskin disorder that is suspected to have an infectious etiology.We aimed to study the role of human herpesvirus-6 (HHV-6) inthe pathogenesis of PR.Method: We used immunohistochemical (IHC) assays to detectHHV-6 in patients with PR. Fifty-one patients with PR and 35 ageand sex matched healthy control samples were enrolled in thestudy. The intensity and percentage of cell staining for HHV-6infection 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 moderateand intense staining for HHV-6 was significantly higher amongpatients with PR than the control group (P value < 0.01).Conclusion: We concluded that HHV-6 infection may play arole in some patients with PR. The rate of HHV-6 infection wassignificantly higher in PR patients than the control group.