A Case Report of JAK Inhibitors Therapy for Adult-Onset Still's Disease with Persistent Pruritic Lesions.

Background And Objective: Adult-onset Still's disease (AOSD) is a recognized autoinflammatory disorder of unknown etiology. The standard initial management for AOSD includes conventional corticosteroids and disease-modifying antirheumatic drugs. In cases that are resistant to these treatments, additional therapeutic options such as immunosuppressants, biologics, and other alternative treatments may be considered. Yet, a significant proportion of patients remain unresponsive to these therapeutic interventions. Herein, a case is reported involving a patient with AOSD who had persistent pruritic lesions that did not respond to conventional therapy, but were alleviated with Janus kinase inhibitors (JAKi), namely baricitinib and upadacitinib. The objective is to expand the number of refractory AOSD cases treated with JAKi in clinical practice. Another aim is to offer potentially effective therapeutic options for AOSD patients who experience persistent pruritus.

Methods: A case was reported involving AOSD characterized by persistent pruritic lesions that failed to respond to conventional treatment, but showed favorable outcomes with JAKi therapy. An analysis of the PubMed literature was performed to assess the medication's efficacy and explore possible mechanisms.

Results: The present case study is one of the few documented instances exploring the use of JAKi for treating AOSD, aligning with previously published research. After initiating JAKi therapy, the patient exhibited significant improvement in symptoms, most notably a reduction in persistent pruritus. Additionally, there was a substantial decrease in the patient's glucocorticoid dosage. Aside from minor renal function anomalies, no adverse reactions were observed.

Conclusions: The present case illustrates that JAKi can provide rapid and sustained clinical improvement in patients with AOSD, especially those who have not responded to conventional treatment, and they have the ability to alleviate persistent itching. Further investigation is needed to ascertain the precise mechanism.