Abstract: Objective To analyze the possible association of psoriasis vulgaris with herpes simplex virus type 1 (HSV-1). Methods Polymerase chain reaction was used to detect HSV-1 DNA in lesional skin biopsies, periphery blood mononuclear cells (PBMCs)and throat swabs from patients with psoriasis vulgaris, and ELISA was used to detect IgM and IgG antibodies against HSV-1 in sera from these patients. Results The positive detection rates of HSV-1 DNA in lesional skin biopsies, PBMCs and throat swabs were 37.5%, 18.6%and 18.8%, respectively. Anti HSV-1 IgM and IgG antibodies were positive in 37.2% and 53.5% of serum specimens, respectively. The detection rates of HSV-1 DNA in lesional skin biopsies and PBMCs, and IgM antibody in sera were significantly higher than those in normal controls. In psoriatic patients of guttate type the positive detection rates of HSV-1 DNA and IgM antibody were significantly higher than those in the plaque type. Conclusions There is strong association of psoriasis vulgaris, especially the guttate type, with HSV-1, and there may be recent infection of HSV-1 in these patients.

Key words: Psoriasis, Herpes simplex virus, type 1, Polymerase chain reaction, Enzyme-linked immunosorbent assay