[Profiles of autoimmune myositis with or without pulmonary involvement: A retrospective single-center study of 40 patients]. / Profils des myosites auto-immunes avec ou sans atteinte pulmonaire : une étude monocentrique rétrospective de 40 patients.

INTRODUCTION: Idiopathic inflammatory myopathies (IMM) are rare diseases with clinico-biological heterogeneity. Pulmonary involvement is frequent and associated with some distinctive manifestations. The aim of this study was to describe the clinico-biological profile of patients with autoimmune myositis with and without pulmonary involvement. METHODS: This retrospective descriptive study included patients with idiopathic inflammatory myopathies and a positive antibody test performed at Grenoble Alpes University Hospital between 2010 and 2020. RESULTS: Forty patients were included, the majority were women. The anti-Jo1 autoantibody was the most frequently found (37.5%). The prevalence of pulmonary involvement was 70%. Mechanics' hands and Raynaud's syndrome were the extra-respiratory signs significantly more present in the group with lung involvement (P <0.05), in contrast to creatine kinase levels which were lower in this group (P <0.05). Glucocorticoids and rituximab were significantly more often used in the group with lung involvement (P <0.05). The 5-year survival rate was 76.2% in patients with lung involvement and 100% in patients without lung involvement (P=0.50). CONCLUSION: We report a high prevalence of lung involvement probably explained by the presence of many patients with anti-synthetase syndrome. Our study highlights a lower severity of muscle involvement in myositis patients with lung disease, which deserves to be confirmed in a larger study.