New Onset and Exacerbation of Psoriasis Following COVID-19 Vaccination: A Review of the Current Knowledge

: COVID-19 vaccination was the main measure to overcome the pandemic. As with other drugs and vaccines, mild to moderate adverse events have been reported following vaccination. In addition, several cutaneous reactions have been described. In particular, there are several reports investigating de novo psoriasis or the exacerbation of psoriasis following COVID-19 vaccination. However, data on the possible pathogenetic mechanisms as well as comprehensive manuscripts on the topic are scant. Thus, the aim of our manuscript was to perform a review of the current literature on post-COVID-19 vaccination exacerbations and new-onset psoriasis in order to offer a wide perspective on this area and to point out possible pathogenetic mechanisms. Research on the current literature was performed following PRISMA guidelines. In total, 49 studies involving 134 patients developing new-onset psoriasis (n = 27, 20.1%) or psoriasis exacerbation (n = 107, 79.9%) were collected. Although cases of de novo psoriasis or a worsening of psoriasis have been reported following vaccination, all of the cases have been successfully treated while overall benefit-risk profile of COVID-19 vaccination does not justify vaccine hesitancy due to the risk of psoriasis being developed or worsening. Certainly, further studies are needed to identify possible pathogenetic mechanisms in order to identify "at-risk" patients. Finally, vaccination should not be discouraged.