Systemic sclerosis associated myopathy: how to treat

Curr Treatm Opt Rheumatol. 2023 Dec;9(4):151-167. doi: 10.1007/s40674-023-00206-y. Epub 2023 Jul 19.

Abstract

Purpose of review: Systemic sclerosis (SSc) and myositis are two different entities that may coexist as an overlap syndrome. Immunological biomarkers such as anti-PM/Scl or anti-Ku reinforce the syndrome. This review is focused on the treatment of different and characteristic manifestations of this syndrome.

Recent findings: Among the different phenotypes of muscle involvement in patients with SSc, the fibrotic pattern and the sporadic inclusion body myositis must be identified early to avoid a futile immunosuppressive treatment. Other forms such as dermatomyositis, non-specific myositis and immune-mediated necrotizing myopathy need to receive conventional immunosuppressive therapy considering that high dose of glucocorticoids may induce a scleroderma renal crisis in patients with SSc. Physicians must be aware of the existence of a "double trouble" association of hereditary myopathy with an autoimmune phenomenon. Several autoantibodies, mainly anti-PM/Scl and anti-Ku may help to define specific phenotypes with characteristic clinical manifestations that need a more specific therapy. Vasculopathy is one of the underlying mechanisms that link SSc and myositis. Recent advances in this topic are reviewed.

Summary: Current treatment of SSc associated myopathy must be tailored to specific organs involved. Identifying the specific clinical, pathological, and immunological phenotypes may help to take the correct therapeutic decisions.

Keywords: Systemic sclerosis; anti-Ku; antiPM/Scl; fibrosis; inflammatory myopathy; myopathy; myositis; vasculopathy.