title: Significant response to immune therapies in a case of subacute necrotizing myopathy and FKRP mutations.
abstract: Necrotizing myopathies can be encountered in various conditions as acquired myopathies (toxic or autoimmune) or muscular dystrophies. We report a twenty-year-old Caucasian woman who presented with clinical findings suggestive of an inflammatory myopathy: subacute onset of lower limb muscle weakness, myalgia, weight loss and absence of family history. The serum creatine kinase level was elevated at 4738 IU/L (normal range, 25-175 IU/L). Muscle biopsy was consistent with necrotizing myopathy. The patient showed significant clinical improvement following corticosteroid, azathioprine and intravenous immunoglobulin treatments. Biological tests revealed no specific autoantibodies associated with necrotizing autoimmune myopathies. Immunohistochemical staining for sarcolemmal proteins in muscle biopsy samples finally led to a diagnosis of limb-girdle muscular dystrophy 2I (fukutin-related protein gene mutations). The response to immune therapies suggested a possible inflammatory component associated with the muscular dystrophy and highlighted the potential benefit of corticosteroid treatment in patients with LGMD2I and subacute onset.
authors.affiliation: Department of Clinical Neurophysiology, Hospices Civils de Lyon, Croix-Rousse University Hospital, Lyon, France. Electronic address: juliette.svahn@chu-lyon.fr.
authors.forename: J
authors.initials: J
authors.lastname: Svahn
authors.affiliation: Department of Neuropathology, Hospices Civils de Lyon, Neurology and Neurosurgery Pierre Wertheimer University Hospital, Lyon, France.
authors.forename: N
authors.initials: N
authors.lastname: Streichenberger
authors.affiliation: Department of Internal Medicine and Clinical Immunology (DHU i2B), Assistance Publique - Hôpitaux de Paris, Pitié-Salpêtrière University Hospital, Paris, France; Sorbonne Universités, Université Pierre et Marie-Curie Paris 6, Myology Research Center UMR 974, INSERM, Paris U974, France.
authors.forename: O
authors.initials: O
authors.lastname: Benveniste
authors.affiliation: Department of Molecular Endocrinology and Rare Diseases, Hospices Civils de Lyon, Lyon, France.
authors.forename: R
authors.initials: R
authors.lastname: Menassa
authors.affiliation: Department of Molecular Endocrinology and Rare Diseases, Hospices Civils de Lyon, Lyon, France.
authors.forename: L
authors.initials: L
authors.lastname: Michel
authors.affiliation: Department of Neurology, Montelimar Hospital Center, Montelimar, France.
authors.forename: H
authors.initials: H
authors.lastname: Fayolle
authors.affiliation: Department of Clinical Neurophysiology, Hospices Civils de Lyon, Croix-Rousse University Hospital, Lyon, France.
authors.forename: P
authors.initials: P
authors.lastname: Petiot
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D001379:Azathioprine / Q000627:therapeutic use; D003402:Creatine Kinase / Q000097:blood; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D007155:Immunologic Factors / Q000627:therapeutic use*; D009132:Muscles / Q000473:pathology / Q000503:physiopathology; D049288:Muscular Dystrophies, Limb-Girdle / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology / Q000628:therapy*; D010430:Pentosyltransferases; D011506:Proteins / Q000235:genetics*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000305:Adrenal Cortex Hormones; D016756:Immunoglobulins, Intravenous; D007155:Immunologic Factors; D011506:Proteins; C443107:FKRP protein, human; D010430:Pentosyltransferases; D003402:Creatine Kinase; D001379:Azathioprine
keywords: Corticosteroid; FKRP mutations; LGMD2I; Muscular dystrophy; Necrotizing myopathy