Guselkumab as a therapeutic option for recalcitrant pyoderma gangrenosum and Crohn disease: a case report and review of the literature.

Pyoderma gangrenosum (PG) is a rare, chronic neutrophilic dermatosis characterized by rapidly progressive, painful ulcers. It is frequently associated with systemic inflammatory conditions such as inflammatory bowel disease. The pathogenesis remains incompletely understood, and treatment of refractory cases poses a significant challenge. We present a 26-year-old woman diagnosed with PG, initially managed with systemic corticosteroids and ciclosporin. During follow-up, she developed gastrointestinal symptoms and was subsequently diagnosed with Crohn disease (CD). Despite treatment with azathioprine, infliximab and, later, ustekinumab, the patient experienced repeated flares of both PG and CD. Upon recurrence of PG lesions and CD exacerbation under ustekinumab therapy, systemic corticosteroids were reintroduced, and subcutaneous guselkumab, an interleukin (IL)-23 p19 inhibitor, was initiated. A rapid and sustained clinical response was observed following the second dose of guselkumab, with complete ulcer healing and tapering off corticosteroids. The patient has remained in complete remission from both PG and CD for over 2 years under guselkumab monotherapy. This case adds to the growing body of evidence supporting the use of IL-23 inhibitors, particularly guselkumab, in recalcitrant PG associated with systemic inflammatory comorbidities. Guselkumab may offer a promising therapeutic alternative in the management of treatment-resistant PG, especially in patients with coexisting CD.