JAK Inhibitor Effectiveness in Giant-Cell Arteritis With Large-Vessel Involvement Assessed by 18F-FDG PET-CT.

We report the case of a 76-year-old woman with relapsing giant-cell arteritis and large-vessel vasculitis demonstrated on 18F-FDG-PET/CT. Methotrexate and tocilizumab failed to achieve remission, and the patient ultimately exhibited a favorable clinical and radiological response to baricitinib, a JAK inhibitor. This case suggests that baricitinib may be a promising treatment for giant-cell arteritis-related large-vessel vasculitis and that 18F-FDG-PET/CT may be used to monitor therapeutic response.