G.P.70

• Published in: Neuromuscular disorders : NMD Vol. 24; no. 9; pp. 815 - 816
• Main Authors: Allenbach, Y, Benveniste, O, Preusse, C, Pehl, D, Goebel, H, Stenzel, W
• Format: Journal Article
• Language: English
• Published: 01.10.2014
• Subjects: Neurology
• ISSN: 0960-8966
• DOI: 10.1016/j.nmd.2014.06.084

The principal classification of inflammatory myopathies is based on a diagnostic approach combining evaluation of a certain clinical syndrome, laboratory results, electromyography and myoimaging with results of a muscle biopsy analysis. Clinical syndromes have been linked to defined entities, and biopsy results have also been recognized as being characteristic for these entities. Numerous studies have evaluated the impact of certain pathomechanisms like a CD8-mediated, MHC-class I-restricted immune response, deposition of complement or distribution of atrophic fibers. Recently a number of muscle-related auto-antibodies (so called MSAs) have been identified and implicated in disease pathogenicity. However, the spectrum of clinical features in one given disease entity is broad and shows numerous variations, the disease-defining clinical features are not well described. Along that line, the morphological spectrum and associated morphological phenomena of one entity (e.g. dermatomyositis) may also be surprisingly large. Morphology is a crucial diagnostic procedure and includes a number of different steps and techniques, however, we believe that all diagnostic possibilities in daily routine have not yet been fully explored. In most publications, authors promote a small number of described patterns like e.g. perifascicular atrophy, MHC class I expression, C5b9 deposition, immune attack of CD8 + T cells, myofiber necrosis etc. Although certainly useful, these patterns have never been analyzed whether they are sufficient, necessary, specific and specific of what. Therefore we have done a large study, based on the identification of a specific clinical syndrome in a group of patients who all harbor one specific auto-antibody. Using a combination of modern techniques, we found distinct myopathological patterns defining specific subgroups of myositis. In addition, molecular (immune) signatures characteristic of certain pathomechanisms are highlighted.