[Necrotizing myopathies: From genetic to acquired forms].

Abstract

Necrotizing myopathies (NM) are defined by histological features. Muscle biopsy demonstrates marked muscle necrosis with regeneration, with little or an absence of inflammatory infiltrate. Histological pattern of NM is unspecific and can be encountered in diverse conditions as acquired myopathies and muscular dystrophies. Among acquired forms of NM, necrotizing autoimmune myopathy (NAM) is a recently recognized sub-group of the idiopathic inflammatory myopathies. Classically, patients present with a subacute severe proximal myopathy, associated with a markedly elevated creatine kinase level, usually greater than 10 times the upper limit of normal. Nevertheless, the clinical presentation can be misleading, with chronic course mimicking muscular dystrophy. Different forms of NAM can be distinguished with various underlying inciting conditions, including autoantibodies to the SRP, autoantibodies to the HMG-CoA reductase, association to connective tissue disease or underlying malignancy. Other associated conditions need yet to be identified. To confirm a diagnosis of NAM, other causes of NM should be excluded as toxic myopathies, muscular dystrophies and other inflammatory myopathies with a misleading histological pattern. NAM is a rare condition but is probably underdiagnosed. Both clinicoserologic and pathologic data must be taken into account to improve this diagnosis. We propose guidelines for diagnosis of NAM according to clinical course, to be used in clinical practice.

• Authors: E Salort-Campana, A M De Paula, D Figarella-Branger, J Pouget
• Journal: La Revue de medecine interne (Rev Med Interne) Vol. 35 Issue 7 Pg. 430-6 (Jul 2014) ISSN: 1768-3122 [Electronic] France
• Vernacular Title: Myopathies nécrosantes : des formes héréditaires aux formes acquises.
• PMID: 24359726 (Publication Type: English Abstract, Journal Article, Review)
• Copyright: Copyright © 2013 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Topics

• Autoimmune Diseases (diagnosis, etiology, genetics)
• Biopsy
• Diagnosis, Differential
• Humans
• Muscle, Skeletal (pathology)
• Muscular Diseases (diagnosis, etiology, genetics)
• Necrosis