Epidemiological, Clinical, Paraclinical, and Progressive Characteristics of Idiopathic Inflammatory Myopathies in the Internal Medicine Department of the Treichville University Hospital in Abidjan

Abstract

Introduction: Idiopathic inflammatory myopathies (IIM) are a group of rare autoimmune diseases that share the common feature of muscle inflammation. The objective was to study the epidemiological, clinical, paraclinical, and evolutionary characteristics of IIM. Materials and Methods : This is a Cross-sectional study conducted in the Internal Medicine Department of Treichville University Hospital from 1 January 2012 to 31 December 2022 (11 years); It included patients of all ages with a definite diagnosis of IIM based on the pathological results of muscle biopsy and/or autoantibodies specific to myositis, or a probable diagnosis according to the 2017 EULAR-ACR criteria. Results: The hospital prevalence of IIM was 0.33%. Women predominated in 58.3% of cases. The age group [35 to 44 years] was the most affected (42%) and the average age at diagnosis was 40 years (range 9 to 81 years). The main manifestations were cutaneous-mucosal (100%) and muscular (83.3%). Myogenic syndrome (58.3%) and suggestive signs on muscle MRI (41.7%) were found. Muscle biopsy and myositis autoantibodies mainly revealed anti-synthetase syndrome (41.7%), followed by dermatomyositis (33.3%). Treatment consisted of corticosteroid therapy (100%) combined with an immunosuppressant (75%). Mortality (25%) was mainly caused by respiratory disorders. Conclusion: Although rare, IIM does exist in Côte d’Ivoire. Mortality remains high and is dominated by respiratory disorders despite corticosteroid therapy often combined with immunosuppressants.