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Updated: May 8, 2026
06:37
Immunolabelling Myofiber Degeneration in Muscle Biopsies
Published on: December 5, 2019
[Necrotizing autoimmune myopathies]
P Petiot1, A Choumert, L Hamelin
1Service de neurologie, centre de référence maladies rares neuromusculaires Rhône-Alpes, groupe hospitalier Nord, 103, grande rue de la Croix-Rousse, 69004 Lyon, France.
Revue Neurologique
|September 4, 2013
Summary
Necrotizing autoimmune myopathies cause severe muscle damage without typical inflammation. Diagnosis requires muscle biopsy, and treatment involves immunosuppressants with variable responses.
Area of Science:
- Neurology
- Immunology
- Pathology
Context:
- Necrotizing autoimmune myopathies (NAMs) are a subset of inflammatory myopathies.
- Characterized by significant muscle fiber necrosis without prominent inflammatory infiltrates.
- Clinical presentation is diverse, often mimicking other idiopathic inflammatory myopathies.
Purpose:
- To outline the diagnostic features and clinical spectrum of necrotizing autoimmune myopathies.
- To highlight key pathological findings and associated antibodies.
- To discuss treatment strategies and response variability.
Summary:
- NAMs present with severe muscle necrosis, often with rhabdomyolysis and elevated creatine kinase levels.
- Muscle biopsy reveals necrosis without T-cell invasion, but may show microangiopathy and complement deposition (C5b9).
- Associated antibodies include anti-SRP and anti-HMGCR (linked to statin-induced NAMs).
Impact:
- Clarifies the distinct pathological features of NAMs within the inflammatory myopathy spectrum.
- Aids in accurate diagnosis through characteristic biopsy findings and antibody testing.
- Informs treatment decisions for this severe autoimmune muscle disease.
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