Palmoplantar Pustulosis-Like Eruption Following Tofacitinib Therapy for Juvenile Idiopathic Arthritis

A 25-year-old Japanese woman with juvenile idiopathic arthritis (JIA) developed a palmoplantar pustulosis–like eruption after starting tofacitinib therapy. This case was significant as it was the first reported instance of such a reaction to tofacitinib, a JAK inhibitor used for rheumatoid arthritis. The eruption appeared 10 days after initiating the treatment and improved upon discontinuation of the drug. However, due to worsening joint symptoms, tofacitinib was reintroduced, leading to the reappearance of the skin condition. The study concluded that tofacitinib likely caused the eruption, although the exact mechanism remained unknown. The case highlighted the need for further reports to understand the pathogenesis of this reaction.