Review article: paradoxical psoriasis as a consequence of tumour necrosis factor antagonists in patients with inflammatory bowel disease

Summary Background Tumour necrosis factor (TNF) antagonists are an efficacious therapy used in the management of several immune‐mediated inflammatory diseases, including inflammatory bowel disease (IBD) and psoriasis. However, since being prescribed more widely, reports of new‐onset psoriatic lesions have began to emerge in the literature and are known as paradoxical psoriasis. Aim To review the evidence available in both the dermatology and gastroenterology literature pertaining to the entity known as paradoxical psoriasis as it relates to IBD and to create a comprehensive guide to assist clinicians who treat this challenging patient population. Methods A literature search was conducted in PubMed to identify manuscripts that presented, discussed or summarised data pertaining to paradoxical psoriasis presenting in individuals with IBD. Results Paradoxical psoriasis is now thought to be a contradictory effect of TNF antagonist therapy leading to psoriatic lesions often within the first year of treatment. The underlying pathogenesis, although not completely understood, is likely related to an imbalance of inflammatory cytokines. The histological appearance, while similar to classical psoriasis, does have unique features. The clinical presentation can vary among patients but often presents during maintenance therapy for inflammatory bowel disease. Treatment options should be determined based upon the severity of the skin lesion, activity of the underlying inflammatory bowel disease and the patient’s unique clinical history. Conclusions The approach to paradoxical psoriasis in IBD should be discussed with a multidisciplinary team to optimise and preserve intestinal disease remission and to ensure the resolution of debilitating skin lesions.