Corticosteroid-sparing benefit of intravenous immunoglobulin in systemic sclerosis-associated myopathy: A comparative study in 52 patients

Abstract Introduction Little is known about systemic sclerosis (SSc)-associated myopathy (SScAM) treatment. Herein we evaluated the use of intravenous immunoglobulin (IVIg) in SScAM. Methods We conducted a retrospective study of patients with SScAM in the Internal medicine department of Cochin University Hospital between 1993 and 2017. Results Fifty-two patients were included comprising 18 (34.6%) with limited SSc and 34 (65.4%) with diffuse SSc. SScAM occurred at a median [interquartile range (IQR)] time of 1 month [0–15] after SSc diagnosis. Thirty-four patients (65.4%) had muscle weakness, 28 (53.8%) had myalgia and 24 (46.2%) had dysphagia. Fifty patients (96.2%) had increased creatine kinase, 22/26 (84.6%) had myopathic electromyography, 10/12 (83.3%) had a high intensity signal of girdle muscles on MRI and 49/50 (98%) had abnormal muscle biopsy. Eighteen (34.6%) patients received IVIg. Severe adverse events occurred in 3/18 (16.7%) patients. When compared to patients who did not receive IVIg, patients who received IVIg had a significantly higher maximal corticosteroid (CS) dose ever, a greater decrease of CS at 3 months, and a lower CS dose at one year and at the end of follow up. Conclusions This study suggests the benefit of IVIg as adjunctive therapy, with an acceptable tolerance profile, and supports its use as a CS-sparing agent, in SScAM.