Evaluation of pityriasis rosea associated with human herpesviruses 6 and 7

Background Pityriasis rosea (PR) is suspected to have an infectious etiology, either viral or bacterial. Although the exact etiology of PR is yet to be identified, speculations exist that the disease is viral in origin, which could be certain strains of the human herpes virus (HHV). Objective To evaluate HHV-6 and HHV-7 as etiological factors for PR. Patients and Methods Plasma samples from 24 patients with PR and from an equal, age-matched and sex-matched healthy control group were tested for the presence of HHV-6 and HHV-7-specific DNA sequences in plasma and peripheral blood mononuclear cells (PBMCs) using nested PCR. Results HHV-6 and HHV-7 DNA were detected in both plasma (33 and 54%, respectively) and PBMCs (50 and 75%, respectively) of patients with PR more than in controls (0% for both in plasma and 16.66 and 33%, respectively, in PBMCs) with more statistical significance for HHV-7. Conclusion This study provides further evidence for HHV-6 and HHV-7 as etiological factors in pityriasis rosea, and detecting HHV-7 DNA in biopsy specimens from skin lesions is recommended.