We read with interest the epidemiologic investigation of the clustering of pityriasis rosea (PR) by Chuh et al.1 The presence of temporal case clustering in patients with antecedent respiratory tract infection during spring and fall, and in some cases of contact with patients with similar exanthem, provides compelling evidence for an infectious etiology. However, the definitive cause of PR remains elusive after many years of research. The causative role of human herpesvirus (HHV) 7 infection remains controversial.2 We report a case of chronic enteroviral infection causing a PR-like rash in which the diagnosis was based on specific immunohistochemical staining of the skin biopsy specimen.
John K. S. Chia, Paul Shitabata, Jie Wu, Andrew Y. Chia. Enterovirus Infection as a Possible Cause of Pityriasis Rosea: Demonstration by Immunochemical Staining. Arch Dermatol. 2006;142(7):927–947. doi:10.1001/archderm.142.7.942