Abstract
TNF inhibitors (TNFi) have revolutionized the therapeutic management of various chronic immune-mediated inflammatory diseases. Despite their known benefits, these therapies are related to paradoxical adverse effects (PAEs), including paradoxical psoriasis (PP). Although the underlying mechanism remains somewhat unclear, some theories suggest that genetic factors, particularly certain single-nucleotide polymorphisms (SNPs), may play an important role. The present review aimed to research and analyze recent findings regarding the pathomechanisms involved in the appearance of PP and the association between various genetic factors and PP in individuals treated with TNFi. We performed a literature search and found that certain genes (IL23R, TNF, FBXL19, CTLA4, SLC12A8, TAP1) are strongly associated with the occurrence of PP in pediatric and adult patients during therapy with TNFi. The identification of the specific SNPs involved in the appearance of PP and other PAEs in patients treated with TNFi for various diseases and in different populations may later favor the recognition of those patients at a high risk of developing such adverse effects and could guide personalized therapeutic strategies in future years.