Neurology 2017 Jan 30;88(5):493-500. Epub 2016 Dec 30.
From the Department of Genome Medicine Development (A.U., A.N., K.H., I.N.), Medical Genome Center, and Department of Neuromuscular Research (A.U., A.N., R.S.T., K.H., I.N.), National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo; Department of Education (A.N.), Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi; Department of Pediatric Neurology (R.S.T.), National Hospital Organization, Utano National Hospital; Department of Neurology (K.H.), Graduate School of Medicine, Kyoto University; Department of Allergy and Rheumatology (M.K.), Nippon Medical School Graduate School of Medicine; and Division of Rheumatology (M.K.), Department of Internal Medicine, and Department of Neurology (Y.W., S.S., N.S.), Keio University School of Medicine, Tokyo, Japan.
: To evaluate the diagnostic value of myxovirus resistance A (MxA) expression in the cytoplasm of myofibers in the diagnosis of dermatomyositis (DM).Methods
: We assessed the sensitivity and specificity of the sarcoplasmic expression of MxA in muscles with DM by immunohistochemistry in consecutive cases of DM (n = 34) and other idiopathic inflammatory myopathies (n = 120: 8 with polymyositis, 16 with anti-tRNA-synthetase antibody-associated myositis, 46 with immune-mediated necrotizing myopathy, and 50 with inclusion body myositis) and compared them with conventional pathologic hallmarks of DM, including perifascicular atrophy (PFA) and membrane attack complex (MAC) deposition on endomysial capillaries.Results
: The sensitivity and specificity of sarcoplasmic MxA expression were 71% and 98%, respectively. Read More