title: Dystrophinopathy mimicking metabolic myopathies.
abstract: Recurrent rhabdomyolysis warrants comprehensive evaluations to search for underlying muscle diseases, including metabolic myopathies, LPIN1-myopathy, RYR1-myopathy, and less commonly muscular dystrophies. The absence of weakness and the normal or minimally elevated creatine kinase levels between attacks are typical of metabolic myopathies, LPIN1-myopathy, and RYR1-myopathy, while the presence of weakness and the highly elevated creatine kinase levels between attacks point toward muscular dystrophies. Here we report a 32-year-old man with a one-year history of recurrent rhabdomyolysis, who had normal strength, slightly elevated baseline creatine kinase level, and normal muscle histopathology. All workups for metabolic myopathies, LPIN1-myopathy and RYR1-myopathy were unrevealing. Next generation sequencing of muscular dystrophy-related genes revealed a hemizygous deletion of exons 17-34 of the dystrophin-encoding gene. Immunohistochemical study revealed absent staining for the rod domain of dystrophin. Dystrophinopathy should be considered in patients with recurrent rhabdomyolysis despite the absence of fixed weakness or highly elevated resting creatine kinase level.
authors.affiliation: Department of Neurology, Anschutz Medical Campus, Mail Stop B-185, 12631 East 17th Avenue, University of Colorado School of Medicine, Aurora, Colorado 80045, USA. Electronic address: teerin.liewluck@ucdenver.edu.
authors.forename: Teerin
authors.initials: T
authors.lastname: Liewluck
authors.affiliation: Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, NAB 2015, Houston, Texas 77030, USA.
authors.forename: Xia
authors.initials: X
authors.lastname: Tian
authors.affiliation: Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, NAB 2015, Houston, Texas 77030, USA.
authors.forename: Lee-Jun
authors.initials: LJ
authors.lastname: Wong
authors.affiliation: Department of Neurology, Washington University School of Medicine, Campus Box 8111, 660 South Euclid Avenue, St. Louis, Missouri 63110, USA.
authors.forename: Alan
authors.initials: A
authors.lastname: Pestronk
mesh_terms: D000328:Adult; D016189:Dystrophin / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology; D009135:Muscular Diseases / Q000175:diagnosis* / Q000235:genetics; D009136:Muscular Dystrophies / Q000150:complications* / Q000175:diagnosis* / Q000235:genetics; D010711:Phosphatidate Phosphatase / Q000235:genetics; D012206:Rhabdomyolysis / Q000150:complications* / Q000235:genetics; D019837:Ryanodine Receptor Calcium Release Channel / Q000235:genetics
chemical_list: D016189:Dystrophin; D019837:Ryanodine Receptor Calcium Release Channel; C485999:LPIN1 protein, human; D010711:Phosphatidate Phosphatase
keywords: Becker muscular dystrophy; Dystrophin; Dystrophinopathy; Metabolic myopathy; Rhabdomyolysis