title: Atypical presentation of GNE myopathy with asymmetric hand weakness.
abstract: GNE myopathy is a rare autosomal recessive muscle disease caused by mutations in GNE, the gene encoding the rate-limiting enzyme in sialic acid biosynthesis. GNE myopathy usually manifests in early adulthood with distal myopathy that progresses slowly and symmetrically, first involving distal muscles of the lower extremities, followed by proximal muscles with relative sparing of the quadriceps. Upper extremities are typically affected later in the disease. We report a patient with GNE myopathy who presented with asymmetric hand weakness. He had considerably decreased left grip strength, atrophy of the left anterior forearm and fibro-fatty tissue replacement of left forearm flexor muscles on T1-weighted magnetic resonance imaging. The patient was an endoscopist and thus the asymmetric hand involvement may be associated with left hand overuse in daily repetitive pinching and gripping movements, highlighting the possible impact of environmental factors on the progression of genetic muscle conditions.
authors.affiliation: Medical Genetics Branch (MGB), National Human Genome Research Institute (NHGRI), National Institutes of Health (NIH), USA.
authors.forename: John Karl L
authors.initials: JK
authors.lastname: de Dios
authors.affiliation: Department of Rehabilitation Medicine, NIH Clinical Center, USA.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Shrader
authors.affiliation: Department of Rehabilitation Medicine, NIH Clinical Center, USA.
authors.forename: Galen O
authors.initials: GO
authors.lastname: Joe
authors.affiliation: Department of Neurology, San Antonio Military Medical Center, USA.
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: McClean
authors.affiliation: Department of Rehabilitation Medicine, NIH Clinical Center, USA.
authors.forename: Kayla
authors.initials: K
authors.lastname: Williams
authors.affiliation: Radiology and Imaging Sciences, NIH Clinical Center, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Evers
authors.affiliation: Medical Genetics Branch (MGB), National Human Genome Research Institute (NHGRI), National Institutes of Health (NIH), USA.
authors.forename: May Christine V
authors.initials: MC
authors.lastname: Malicdan
authors.affiliation: Medical Genetics Branch (MGB), National Human Genome Research Institute (NHGRI), National Institutes of Health (NIH), USA.
authors.forename: Carla
authors.initials: C
authors.lastname: Ciccone
authors.affiliation: National Institute of Neurological Disorders and Stroke (NINDS), NIH, USA.
authors.forename: Ami
authors.initials: A
authors.lastname: Mankodi
authors.affiliation: Medical Genetics Branch (MGB), National Human Genome Research Institute (NHGRI), National Institutes of Health (NIH), USA.
authors.forename: Marjan
authors.initials: M
authors.lastname: Huizing
authors.affiliation: Therapeutics for Rare and Neglected Diseases (TRND), National Center for Advancing Translational Sciences (NCATS), NIH, USA.
authors.forename: John C
authors.initials: JC
authors.lastname: McKew
authors.affiliation: Radiology and Imaging Sciences, NIH Clinical Center, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Bluemke
authors.affiliation: Medical Genetics Branch (MGB), National Human Genome Research Institute (NHGRI), National Institutes of Health (NIH), USA.
authors.forename: William A
authors.initials: WA
authors.lastname: Gahl
authors.affiliation: Therapeutics for Rare and Neglected Diseases (TRND), National Center for Advancing Translational Sciences (NCATS), NIH, USA. Electronic address: carrilln@mail.nih.gov.
authors.forename: Nuria
authors.initials: N
authors.lastname: Carrillo-Carrasco
mesh_terms: D000328:Adult; D012090:Cumulative Trauma Disorders / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D005500:Follow-Up Studies; D006225:Hand / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009097:Multienzyme Complexes / Q000235:genetics*; D018908:Muscle Weakness / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology; D009135:Muscular Diseases / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology*
chemical_list: D009097:Multienzyme Complexes; C482901:UDP-N-acetylglucosamine 2-epimerase - N-acetylmannosamine kinase
keywords: Distal myopathy with rimmed vacuoles (DMRV); GNE myopathy; Hereditary inclusion body myopathy (HIBM); Inclusion body myopathy 2; N-acetylmannosamine (ManNAc); Nonaka myopathy; Sialic acid