NGHIÊN CỨU ĐẶC ĐIỂM LÂM SÀNG VÀ MÔ BỆNH HỌC CỦA BỆNH VIÊM CƠ VÔ CĂN

Abstract

Background: Idiopathic inflammatory myopathies (IIMs), also known as myositis, are a heterogeneous group of chronic autoimmune conditions affecting the muscles and extra muscle tissues/ organs with varying clinical manifestations, treatment responses and prognosis.  Objectives: This study aimed to describe the clinical and histopathology in the diagnosis of idiopathic inflammatory myopathies and sub-groups classification. Materials and methods: Retrospective, descriptive case series. A total of 46 patients were diagnosed with IIMs at the Department of Pathology, University of Medicine and Pharmacy at Ho chi Minh city from January 1st, 2019, to June 31st, 2022. Results: The mean age at diagnosis of IIMs was 45.53 ± 17.3 years old; the male ratio was 2.29:1. 73.9% of cases presented muscle weakness, primarily proximal extremities. The average blood CK concentration was 4472.96 ± 4189.42 U/L. 2.8% of patients showed no abnormalities on electromyography, and 97.2% presented abnormalities. The highest percentage of MSA was anti-SRP (18.8%), followed by anti-HMGCR (12.5%), and the highest frequency of MAA was anti-Ro (18.8%). Thirty-four cases (73.9%) had infiltration of inflammatory cells in endomysium. There were no cases with rimmed vacuole. Muscle fiber necrosis was observed in 28/46 cases (60.9%), myophagocytosis in 15/46 cases (32.6%) and perifasicular atrophic fiber 5/46 cases (10,9%). Conclusions: Diagnosis of IIMs and subtype should be based on clinical symptoms, muscle enzymes, serological tests, electromyography, imaging and histopathology.