Specialty Neurology Neurology 5 5 Chapter Specific Polymyositis (PM); Polymyositis (PM) Conditions Dermatomyositis (DM); Dermatomyositis (DM) Inclusion body myositis (IBM) Necrotising autoimmune myopathy (NAM) of Evidence of probable benefit (Category PM and DM Evidence of probable benefit Level of evidence was confirmed for all – Evidence 2a). (Category 2a). specific conditions. NAM Small case studies only, insufficient data – (Category 4a) Description The inflammatory myopathies are a Dermatomyositis and polymyositis are idiopathic Diagnostic criteria have been revised and and group of three discrete disorders of inflammatory myopathies. Necrotizing autoimmune updated including NAM. Diagnostic skeletal muscle: DM, PM and IBM. myopathy typically has necrotic myofibres with less (A) Criteria inflammatory infiltrate and the absence of direct These disorders are acquired and have myocyte invasion by lymphocytes. These disorders in common the occurrence of significant are acquired and have in common the occurrence of muscle weakness and the presence of significant muscle weakness and the presence of an an inflammatory response within the inflammatory response within the muscle. The muscle. weakness usually develops subacutely but may be The diagnosis of DM, PM or IBM is chronic and present over many months. Proximal usually made muscles are predominantly affected in a symmetric fashion. by neurologists or rheumatologists, and relies on
Specialty Neurology Neurology Chapter 5 5 Specific Conditions Polymyositis (PM); Dermatomyositis (DM); Inclusion body myositis (IBM) Polymyositis (PM) Dermatomyositis (DM) Necrotising autoimmune myopathy (NAM) of Evidence Evidence of probable benefit (Category 2a). PM and DM – Evidence of probable benefit (Category 2a). NAM – Small case studies only, insufficient data (Category 4a) Level of evidence was confirmed for all specific conditions. Description and Diagnostic Criteria The inflammatory myopathies are a group of three discrete disorders of skeletal muscle: DM, PM and IBM. These disorders are acquired and have in common the occurrence of significant muscle weakness and the presence of an inflammatory response within the muscle. The diagnosis of DM, PM or IBM is usually made by neurologists or rheumatologists, and relies on Dermatomyositis and polymyositis are idiopathic inflammatory myopathies. Necrotizing autoimmune myopathy typically has necrotic myofibres with less inflammatory infiltrate and the absence of direct myocyte invasion by lymphocytes. These disorders are acquired and have in common the occurrence of significant muscle weakness and the presence of an inflammatory response within the muscle. The weakness usually develops subacutely but may be chronic and present over many months. Proximal muscles are predominantly affected in a symmetric fashion. Diagnostic criteria have been revised and updated including NAM. (A)
inflammatory-myopathies-polymyositis%28pm%29-dermatomyositis%28dm%29-and-necrotising-autoimmune-myopathy%28nam%29.DOCX