Successful use of tofacitinib in the treatment of diffuse systemic sclerosis and axial spondyloarthritis: a case-based review.

Systemic sclerosis (SSc) is an autoimmune rheumatic disease characterised by vasculopathy, inflammation and fibrosis in multiple organs and occasionally coexists with rheumatic conditions, such as axial spondyloarthritis (axSpA). The aim of this study was to demonstrate the successful use of tofacitinib in SSc and axial spondylarthritis (axSpa), as a novel therapeutic agent; however, further studies are needed to elucidate the role of JAK inhibition in the treatment of both conditions. In this paper, we report a case of a 58-year-old woman with diffuse SSc who developed axSpA. The patient had a 10-year history of SSc and was treated with tocilizumab before the onset of lower back pain. The diagnostic evaluation included MRI that demonstrated bone marrow oedema in the sacroiliac joints, the HLA-B27 was positive, and given the inflammatory features of her back pain, she was diagnosed with axSpa. The biologic agent was switched into etanercept with an improvement of the back pain; however, the patient had a relapse of her skin manifestations. Given the treatment failure, we aim to treat the 2 coexisting conditions concurrently with tofacitinib, which led to symptom improvement. This case report is noteworthy, given the rarity of the coexistence of both conditions and the therapeutic challenges faced by the clinician. The online database MEDLINE/PubMed and Scopus where searched for articles published from inception to June 2020, using the terms "ankylosing spondylitis" AND "systemic sclerosis" OR "axial spondyloarthritis" AND "systemic sclerosis". Also, we searched the American College of Rheumatology and European League Against Rheumatism annual meeting abstracts from 2015 to 2019 using the same terms. As a result, we found 9 similar case reports. 9 case reports of patients with both conditions were identified through a literature review and we highlighted the differences and similarities between them. Also, we emphasise on intracellular signalling inhibitors as novel therapeutic targets in treating both conditions. Tofacitinib might be a novel therapeutic agent in the management of SSc and axSpA.