Tofacitinib treatment for psoriatic skin lesions associated with Aicardi-Goutières syndrome 7/Singleton-Merten syndrome 1

The purpose of this letter to the editor is to illustrate the effect of tofacitinib on psoriatic skin lesions in a patient with Aicardi-Goutières syndrome (AGS) type 7/Singleton-Merten syndrome 1. AGS is characterized by an encephalopathy of variable severity and systemic autoinflammatory manifestations due to continuous type I interferon (IFN) induction. While traditional JAK 1/2 inhibitors like baricitinib and ruxolitinib have proven effectiveness for systemic inflammatory symptoms, they face reimbursement issues in some countries. Tofacitinib, a JAK 1/3 inhibitor, significantly improved psoriatic skin lesions in our patient without the need for additional immunosuppressive therapy. Within one month of starting tofacitinib, psoriatic rashes and ulcerative skin lesions markedly improved, in the absence of a reduction in the IFN-stimulated gene signature or CD169 expression on monocytes. The clinical benefits persisted until the treatment was discontinued, after which symptoms recurred. Resuming tofacitinib treatment again led to improvement. No adverse effects were observed. This case highlights the potential of tofacitinib as a clinically effective treatment for psoriatic skin lesions in AGS and offers a viable alternative for JAK 1/2 inhibitors for this target symptom. Further studies are needed to confirm the long-term safety of JAK 1/3 inhibitors in AGS as well as their possible efficacy and dosing to address other systemic symptoms or neurologic manifestations.