Systemic Sclerosis‐Associated Myopathy

Abstract

Skeletal muscle involvement is a common feature in systemic sclerosis (SSc) because muscle weakness is found in up to 90% SSc patients when systematically assessed. Muscle clinical, biological, and electromyographic features are similar to those of polymyositis or dermatomyositis, except for a higher proportion of mild symptoms. SSc-associated myopathy is more prevalent in diffuse SSc and is also associated with cardiomyopathy. The pathophysiological process leading to SSc-associated myopathy is likely to be complex, given the heterogeneity of pathological muscle findings, including stigma of microangiopathy, and also inflammatory infiltrate in about half of the cases and interstitial fibrosis. Conflicting results have been reported regarding the correlation between clinicobiological presentation and pathological muscle features, nevertheless there is a general agreement that histologically proven inflammatory myopathies usually regress under high-dose corticosteroid therapy, or even low dose in case of positive anti-PM/Scl antibody. In contrast, noninflammatory myopathies often result in milder clinical expression but do not respond to immunosuppressive treatment.

The rehabilitation of facial involvement in systemic sclerosis: efficacy of the combination of connective tissue massage, Kabat’s technique and kinesitherapy: a randomized controlled trial

“…Systemic Sclerosis (SSc) is characterised by induration of the skin and internal organs, by joint modifications and muscle impairment [1][2][3][4][5]. Skin fibrosis leads to tissue retraction and atrophy, and consequently to disability and reduction of patients quality of life (QoL).…”

Envolvimento das musculaturas esquelética e cardíaca na esclerose sistêmica

“…Although clinically less expressive, non-infl ammatory myopathy responds poorly to immunosuppressant treatment. 2,7 In our study, we observed a 42.5% prevalence of muscle involvement in the form of muscle weakness, atrophy and/or CPK elevation in patients with SSc. The same assessment in other studies has shown prevalence between 16% and 81%, refl ecting the heterogeneity of the criteria used to defi ne muscle involvement in SSc.…”

“…7,8 The histological fi ndings are heterogeneous and include both the infl ammatory myopathy component and specifi c fi ndings of SSc in varied proportions: from infl ammatory infi ltrates, necrosis, and atrophy to microangiopathy and fi brosis of the perimysium and epimysium. 7,8 The diagnostic criteria for muscle involvement in SSc have not been well defi ned, and neither has the superposition SSc/ polymyositis versus SSc-associated myopathy. 7 The myositis type of SSc has a favorable prognosis and usually responds adequately to corticoids.…”

“…7 The latter does not have a consensual defi nition and usually includes muscle involvement without infl ammation. The alterations found on the electroneuromyography of patients with SSc are similar to those evidenced in idiopathic infl ammatory myopathies.…”

“…7,8 The diagnostic criteria for muscle involvement in SSc have not been well defi ned, and neither has the superposition SSc/ polymyositis versus SSc-associated myopathy. 7 The myositis type of SSc has a favorable prognosis and usually responds adequately to corticoids. Although clinically less expressive, non-infl ammatory myopathy responds poorly to immunosuppressant treatment.…”