Infliximab-Induced Psoriasis in an Ulcerative Colitis Patient Successfully Treated with Guselkumab: A Case Report

Ulcerative colitis (UC) is a chronic inflammatory disorder of the gastrointestinal tract. Tumor necrosis factor (TNF) inhibitors such as infliximab (IFX) are used to treat UC. But TNF inhibitors can induce psoriasis, which was characterized by IL-17/IL-22 expressing Th17 cells and IFN-γ expressing Th1 cells, with increased expression of Th17 cells correlated with more severe skin lesions and a need for Ustekinumab (UST) therapy1. UST is a monoclonal antibody that binds to the p40 subunit of the interleukin (IL)-12 and IL-23. It has shown remarkable efficacy in psoriasis and UC2. Guselkumab, a subcutaneously administered fully human IgG1 monoclonal antibody that selectively inhibits the p19 subunit of IL-23, is approved for the treatment of patients with moderate-to-severe plaque psoriasis3. It was shown to be efficacious in patients with prior failure of other biologics such as UST and was also observed in the treatment of psoriasis localized in difficult-to-treat body regions including the scalp, palms, soles, and fingernails. We report a case of successful use of guselkumab to treat a UC patient with IFX-induced psoriasis that was refractory to UST therapy.