Case Report: Successful management of refractory SAPHO syndrome with guselkumab-upadacitinib combination.

SAPHO syndrome is a rare chronic aseptic inflammatory disorder characterized by the concurrence of osteoarticular inflammation and cutaneous lesions. The intricate mechanism network, coupled with issues such as paradoxical reactions, often results in suboptimal therapeutic outcomes. To the best of our knowledge, this is the first report of refractory SAPHO syndrome achieving clinical remission with the combination of guselkumab (an IL-23 inhibitor) and upadacitinib (a JAK inhibitor). A 38-year-old male with refractory SAPHO experienced complete pain resolution within 2 weeks and significant improvement in cutaneous lesions by 4 weeks post-treatment, with a favorable safety profile observed throughout the follow-up period. We further analyzed the underlying inflammatory mechanisms to provide a therapeutic clues for the management of similar refractory cases.