Is human herpesvirus 7 the causative agent of pityriasis rosea?--A critical review.

Background: Conflicting results on the association of pityriasis rosea and human herpesvirus 7 infection have been reported by different investigators.

Aim: To review the level of evidence for such an association.

Methods: Medline was searched with unlimited data entry and 13 reports were retrieved. The data were analyzed for a causative association according to the criteria of Fredericks and Relman, which take into consideration latent infection and the reactivation of viruses characteristic of herpesviruses, and the roles of sequence-based detection methods.

Results: None of the criteria was substantiated by the findings of most investigators. Factors leading to the discrepancies of the results were discussed.

Conclusion: There is currently insufficient evidence that human herpesvirus 7 infection is causally related to pityriasis rosea.