Tofacitinib in the Treatment of Refractory Adult-Onset Still's Disease Co-diagnosed With Celiac Disease: A Case Report.

Adult-onset Still's disease (AOSD) is an autoinflammatory disease characterized by systemic and musculoskeletal manifestations driven by dysregulated cytokine activity. Fevers, evanescent salmon-colored rash, and transaminitis are hallmark features of the systemic subset of AOSD. Macrophage activation syndrome (MAS) represents the most feared and potentially life-threatening complication of AOSD. Tofacitinib, a Janus kinase (JAK) inhibitor, is approved for the management of several autoimmune conditions. We present a case of a 31-year-old woman with AOSD co-diagnosed with celiac disease, who was refractory to high-dose corticosteroids and tocilizumab. Initiation of tofacitinib led to marked clinical and laboratory improvement, enabling complete cessation of prednisolone. This case contributes to the limited body of literature supporting the use of tofacitinib in refractory AOSD and represents only the second reported instance of overlap between AOSD and celiac disease.