[Paradoxical psoriasis induced by anti-TNF - a clinical challenge].

Anti-TNFs have revolutionized the management of numerous chronic inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis. Although anti-TNF drugs are highly effective, 2-5 % of treated patients develop psoriasis-like skin lesions called paradoxical psoriasis. Paradoxical psoriasis is specific to anti-TNFs and it is, despite clinically resembling classical psoriasis, immunologically distinct. As it frequently requires cessation of the anti-TNF therapy, paradoxical psoriasis is a critical drug side effect and a challenge in the management of patients with chronic inflammatory diseases. In this review, we discuss the clinical, histological and pathogenic distinctions between the two entities and the management of patients developing paradoxical psoriasis.