Rapid remission of refractory synovitis, acne, pustulosis, hyperostosis, and osteitis syndrome in response to the Janus kinase inhibitor tofacitinib: A case report

BACKGROUND Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare autoinflammatory disease for which clinical treatment has not been standardized. Janus kinase (JAK) inhibitors represent a novel therapeutic option for rheumatoid arthritis, psoriatic arthritis, and some other autoinflammatory diseases. However, the clinical utility of JAK inhibitors in treating SAPHO syndrome has not been thoroughly investigated. In this study, we describe a patient with SAPHO syndrome who failed to respond to conventional treatment but demonstrated a remarkable and rapid response to the JAK inhibitor tofacitinib. CASE SUMMARY A 62-year-old female patient presented with swelling and pain at the sternoclavicular joints, back pain that limited her activities, arthralgia in the right knee, and cutaneous lesions. Her symptoms were unresponsive to nonsteroidal anti-inflammatory drugs, disease-modifying antirheumatic drugs, Tripterygium wilfordii hook f, and bisphosphonates. SAPHO syndrome was diagnosed in accordance with dermatological and osteoarticular manifestations and abnormal inflammatory factors. Multiple image studies have illustrated bone lesions and pathological fractures of vertebral bodies. Oral treatment with tofacitinib at 5 mg twice daily with methotrexate and bisphosphonates was initiated. The patient reported that her pain symptoms were relieved after 3 d and her cutaneous lesions were reduced after 4 wk of treatment. Vertebral lesions were improved after 6 mo on tofacitinib. No serious adverse effects were noted. CONCLUSION JAK inhibitor therapy may be a promising strategy to treat SAPHO syndrome.