title: Anti-3-hydroxy-3-methylglutaryl-coenzyme a reductase necrotizing myopathy masquerading as a muscular dystrophy in a child.
abstract: BACKGROUND
  Immune-mediated necrotizing myopathies (IMNMs) are characterized by progressive weakness, elevated serum creatine kinase levels, and necrotizing myopathic features on muscle biopsy. Presence of highly specific autoantibodies against signal recognition particle (SRP) or 3-hydroxy-3-methylglutaryl- coenzyme A reductase (HMGCR) can aid in recognition and confirmation of IMNMs.
  
  
  METHODS
  In this study we describe a boy with HMGCR-positive necrotizing myopathy and highlight the clinical features of the patient.
  
  
  RESULTS
  In contrast to most adults, the patient described had a more indolent disease course, reminiscent of a muscular dystrophy. Intravenous immunoglobulin monotherapy resulted in a dramatic clinical response with return to normal strength.
  
  
  CONCLUSIONS
  Systematic consideration of IMNMs and testing for relevant autoantibodies in children with suspected but genetically unconfirmed muscular dystrophy may help improve diagnostic accuracy and allow timely treatment with potentially highly effective immunotherapies. Muscle Nerve 56: 175-179, 2017.
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Payam
authors.initials: P
authors.lastname: Mohassel
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: A Reghan
authors.initials: AR
authors.lastname: Foley
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Sandra
authors.initials: S
authors.lastname: Donkervoort
authors.affiliation: Department of Pediatrics, Division of Pediatric Neurology, University of Alabama at Birmingham, Birmingham, Alabama, USA.
authors.forename: Pierre R
authors.initials: PR
authors.lastname: Fequiere
authors.affiliation: Muscle Disease Unit, Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Building 50, Room 1146, Bethesda, Maryland, 20892, USA.
authors.forename: Katherine
authors.initials: K
authors.lastname: Pak
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Carsten G
authors.initials: CG
authors.lastname: Bönnemann
authors.affiliation: Muscle Disease Unit, Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Building 50, Room 1146, Bethesda, Maryland, 20892, USA.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Mammen
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood*; D003937:Diagnosis, Differential; D006801:Humans; D006903:Hydroxymethylglutaryl CoA Reductases / Q000097:blood*; D008297:Male; D009135:Muscular Diseases / Q000097:blood* / Q000000981:diagnostic imaging*; D009136:Muscular Dystrophies / Q000097:blood / Q000000981:diagnostic imaging; D009336:Necrosis / Q000097:blood / Q000000981:diagnostic imaging
chemical_list: D001323:Autoantibodies; C553220:HMGCR protein, human; D006903:Hydroxymethylglutaryl CoA Reductases
keywords: HMGCR; IVIg; linear scleroderma; muscular dystrophy; myositis; necrotizing myopathy