title: A Novel Variant in the HINT1 Gene in a Girl with Autosomal Recessive Axonal Neuropathy with Neuromyotonia: Thorough Neurological Examination Gives the Clue.
abstract: We report a girl with autosomal recessive axonal neuropathy with neuromyotonia (ARAN-NM) who presented with asymmetric gait impairment, foot drop, and action myotonia on fast handgrip. Electrophysiological studies showed symmetrical axonal motor greater than sensory neuropathy, and neuromyotonic discharges on needle electromyography. ARAN-NM was confirmed by molecular genetic testing, which revealed a novel homozygous missense variant c.100G > A [p.(Glu34Lys)] in HINT1. This case shows that the diagnosis of ARAN-NM, as a new entity, has to be considered in the differential diagnosis of polyneuropathy in combination with neuromyotonia/action myotonia in children, even with asymmetric clinical presentation.
authors.affiliation: Department of Pediatrics, Hospital Ostallgäu-Kaufbeuren, Kaufbeuren, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Rauchenzauner
authors.affiliation: Department of Pediatrics, Hospital St. Vinzenz, Zams, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Frühwirth
authors.affiliation: Department of Neurology, Bezirkskliniken Schwaben, Kaufbeuren, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Hecht
authors.affiliation: Department of Neurology, Hochzirl Hospital, Zirl, Austria.
authors.forename: Markus
authors.initials: M
authors.lastname: Kofler
authors.affiliation: Division of Human Genetics, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: Martina
authors.initials: M
authors.lastname: Witsch-Baumgartner
authors.affiliation: Division of Human Genetics, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: Christine
authors.initials: C
authors.lastname: Fauth
mesh_terms: D002648:Child; D004576:Electromyography; D005260:Female; D005808:Genes, Recessive; D015417:Hereditary Sensory and Motor Neuropathy / Q000175:diagnosis*; D006801:Humans; D020386:Isaacs Syndrome / Q000175:diagnosis* / Q000235:genetics* / Q000503:physiopathology; D018482:Muscle, Skeletal / Q000503:physiopathology; D020125:Mutation, Missense; D009419:Nerve Tissue Proteins / Q000235:genetics*; D009431:Neural Conduction; D009460:Neurologic Examination
chemical_list: C063306:HINT1 protein, human; D009419:Nerve Tissue Proteins