Complete Clearance of Pustular Psoriasis After A Single Dose of Risankizumab.

Introduction: Psoriasis is a chronic, multifactorial, inflammatory skin disease with several subtypes, including pustular psoriasis. Pustular psoriasis is characterized by pustules forming lakes of pus on the skin. Pro-inflammatory pathways, such as the interleukin (IL)-17/IL-23 axis, have been shown to play a significant role in the pathogenesis of psoriasis. Biologic therapies directed towards these pro-inflammatory pathways have effectively treated plaque psoriasis, but fewer treatments have shown similar efficacy for pustular psoriasis. Case Presentation: We present a 45-year-old Black female who presented to the dermatology clinic with generalized pustular psoriasis affecting approximately 70% of her body surface area. She also noted joint stiffness and pain that was worse after inactivity. Her disease did not respond to previous treatment, which was using adalimumab for 6 months. She also had no response to a 3-month course of apremilast.Two weeks after receiving her first dose of risankizumab, she had complete clearance of her pustular psoriasis, affecting 0% of her body surface area. She also noted significant improvement in her joint pain. Conclusions: There is little data regarding the efficacy of IL-23 inhibitors in treating generalized pustular psoriasis. To date, our case is the only reported instance in the literature showing rapid clearance of pustular psoriasis after 1 injection of risankizumab. This case illustrates that IL-23 inhibitors play an essential role in the rapid clearance of pustular psoriasis.