Some progress in pityriasis rosea

Recent studies have found that some viruses,including human herpesvirus (HHV)-6,HHV-7,HHV-8,influenza A (H1N1) virus,as well as a variety of drugs are involved in the pathogenesis of PR.The cell immunity mediated by T lymphocytes plays an important role in the development of pityriasis rosea (PR).In addition,HLA-DQB1*04 allele may be associated with the genetic susceptibility to PR.Some patients with PR may show atypical manifestations in rash shape,size,distribution,location,number and duration.Pregnant women with PR have a higher incidence of premature birth and abortion.Drug-induced PR appears more severe than classical type of PR.There is no specific therapy for PR.Acyclovir,ultraviolet B (UVB) and UVA1 have shown attractive efficacy in the clinical treatment of some types of PR. Key words: Pityriasis rosea;  Immunity;  Therapy