(from the 2025 Neuropathology in Practice Forum, Canadian Association of Neuropathologists Annual Meeting, Banff, AB, October 24, 2025)
This document summarizes the recommendations of the Canadian Association of Neuropathologists with respect of the diagnostic work-up of inflammatory myopathies. These recommendations are based on the current medical literature and presentations and discussions during the 2025 Neuropathology in Practice Forum.
Immunohistochemical markers of inflammatory pathways and autophagy have become standard for the myopathological characterization of inflammatory myopathies within a clinico-sero-pathological classification. The present recommendations summarize current markers and try to give a tiered approach to their implementation ranging from core recommendations to additional options. These recommendations are not designed to shape an approach to muscle biopsy evaluation in general, but to guide work-up in cases of a reasonable suspicion of an inflammatory myopathy with the aim of classifying the subtype of inflammatory myopathy. Exclusion of other types of pathologies relies on general myopathological evaluation and clinico-pathological correlation.
Finally, a listing of national resources is also included for reference.
Submitted respectfully,
Invited Speakers/Primary Authors:
Dr. Peter Schutz MD PhD Dr. Benjamin Ellezam MD PhD
Vancouver General Hospital Centre Hospitalier Universitaire Sainte-Justine
University of British Columbia University of Montreal
Moderator/Editor:
Dr. Robert Hammond MD
London Health Sciences Centre
Western University
January 2026