Role of Cytomegalovirus Infection and Tumor Necrosis Factor-α in Psoriasis

Background. Psoriasis is a common cutaneous disorder characterized by inflammation and abnormal epidermal proliferation. More than 40% of psoriatic patients reported a provoking infection. Active and subclinical cytomegalovirus (CMV) infection may be of pathophysiological importance in psoriasis.Cytomegalovirus super-antigen has been suggested, as well as inflammatory cytokines especially tumornecrosis factor-alpha (TNF-a), to be involved in the pathogenesis of the disease. Aim of the study. to detecta possible role of CMV infection in psoriasis occurring as a result of CMV antigenaemia associated with over-expression of TNF-a in psoriasis. Patients and methods. 35 patients complaining from psoriasis were included in this study in addition to fifteen healthy controls. Two blood samples were taken from each individual: the first was to detect CMV antigenaemia by PCR technique and the second was to evaluate the serum level of TNF-a using the ELISA technique. Results. in our study the mean value of TNF-a in thepsoriatic patients was statistically significantly higher than in the healthy controls and the mean value of TNF-α in the CMV positive patients was statistically significantly higher than in CMV negative patients.Conclusion. The role of CMV infection in psoriasis could be due to either virus induced immune activation state leading to increased secretion of cytokines as TNF-α or that the inflammation process associated with psoriasis is accompanied by elevation of serum TNF-a resulting in subclinical activation of a latent CMV infection.