Tofacitinib citrate for the treatment of refractory, severe chronic actinic dermatitis

CAD: chronic actinic dermatitis JAK: Janus kinase TCR: T cell receptor UV: ultraviolet INTRODUCTION Chronic actinic dermatitis (CAD) is an uncommon inflammatory dermatosis characterized by dermatitis involving ultraviolet (UV) lighteexposed skin with notable sparing of sun-protected areas. Rarely, spread of the exanthema to UV-protected areas of skin and even erythroderma with palmoplantar hyperkeratosis occurs. CAD typically afflicts men in the fifth decade of life or older. Although the pathophysiology remains unknown, it is thought that lymphocyte recognition of UV-induced neoantigens in the skin underlies this process. Furthermore, cross-reactivity to exogenous contact antigens may also be contributing, as allergic contact dermatitis to numerous allergens has been reported in more than 50% of affected individuals. Management involves strict photoprotection, topical corticosteroids, topical calcineurin inhibitors, prednisone, and immunomodulatory agents, often with only limited success. Herein, we report a case of severe CAD refractory to all common immunomodulatory agents that was successfully remitted with the Janus kinase (JAK)1/3 inhibitor tofacitinib citrate.