Updates in Treatment of Refractory Inflammatory Myositis


  • Kun Huang, MD, PhD, FRCPC Department of Medicine, University of British Columbia, Vancouver, British Columbia Division of Rheumatology, Vancouver General Hospital, Vancouver, British Columbia Division of Rheumatology, Surrey Memorial Hospital, Surrey, British Columbia Arthritis Research Canada, Vancouver, British Columbia
  • Aidan Pye, MD Department of Medicine, University of British Columbia, Vancouver, British Columbia


Idiopathic immune myopathies (IIM), also known as myositis, are a heterogeneous group of autoimmune diseases with varying phenotypes, prognoses, and treatment responses. They are primarily characterized by muscle inflammation, however, many patients have extramuscular involvement including skin rash, arthritis, interstitial lung disease (ILD), cardiomyopathy, and gastrointestinal dysmotility. The discovery of myositis-specific autoantibodies (MSAs) has been a major advancement in the field of IIMs, shaping the new landscape of the clinical, phenotypical, histological, and serological correlations. Based on this discovery, IIM can be more specifically classified into dermatomyositis (DM) (including amyopathic DM), antisynthetase syndrome (ASyS), immune-mediated necrotizing myopathy (IMNM), inclusion body myositis (IBM), polymyositis (PM), and overlap myositis (OM). An increasing number of histological studies have revealed a misdiagnosis of PM because many patients who were previously diagnosed with PM were later reclassified to other forms of IIM, including IBM, IMNM, ASyS, or DM without a rash.

Author Biographies

Kun Huang, MD, PhD, FRCPC, Department of Medicine, University of British Columbia, Vancouver, British Columbia Division of Rheumatology, Vancouver General Hospital, Vancouver, British Columbia Division of Rheumatology, Surrey Memorial Hospital, Surrey, British Columbia Arthritis Research Canada, Vancouver, British Columbia

Dr. Kun Huang is a rheumatologist at Surrey Memorial Hospital and a myositis specialist at the Mary Pack Arthritis Program at Vancouver Coastal Health. She is a clinical assistant professor at the University of British Columbia and a clinical investigator at the Arthritis Research Canada. She has an academic focus in inflammatory myositis therapies and outcome.

Aidan Pye, MD, Department of Medicine, University of British Columbia, Vancouver, British Columbia

Dr. Aidan Pye is a first-year internal medicine resident at the University of British Columbia with an interest in rheumatology. He completed his undergraduate degree in chemistry at the University of Victoria and MD at the University of British Columbia.


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How to Cite

Huang K, Pye A. Updates in Treatment of Refractory Inflammatory Myositis. Can Rheumatol Today [Internet]. 2024 Apr. 23 [cited 2024 Jun. 24];1(1):19–26. Available from: https://canadianrheumatologytoday.com/article/view/1-1-Huang_et_al