RESUMO
Objective To investigate the efficacy of tumor necrosis factor alpha (TNF-α) antagonists therapy and the possible eauses of new onset or exacerbation of psoriatic skin lesion in patients with arthritides treated with TNF-α atagonists therapy. Methods One patient with definite psoriatie arthritis and one patient with definite ankylosing spondylitis, who were treated with TNF-α antagonist therapy developed an unexpected exacerbation or new onset of psoriatic skin lesion, were investigated in this study. Furthermore, the literatures associated with psoriasis induced by anti-TNF-α therapy were reviewed. Results The patient with psoriatic arthritis experienced exacerbation of psoriatic skin lesion and the skin lesions subsided after discontinuation ofetanereept therapy. The skin lesions recurred with re-introduction of etanereept, which improved after withd-rawal of etanercept therapy. The patient with ankylosing spondylitis unexpectedly developed psoriasis vulgaris after receiving etanercept therapy. The skin lesion waxed and waned followed the administration or discon-tinuation of etanercept therapy. The same settings were reported in patients with rheumatoid arthritis receiving different types of anti-TNF-α therapy. Conclusion Blockage of TNF-α is highly effective in arthritides. Ho-wever, some patients with arthritides can unexpectedly develop either a new onset or exacerbation of psoriatic skin lesions after initiation of TNF-α antagonist therapy. The skin lesions subside after discontinuation of the TNF-α antagonist therapy, but the causes remain unclear.