title: Adult-onset acid maltase deficiency with isolated axial muscle involvement.
abstract: BACKGROUND
  We report a patient with acid maltase deficiency who presented with subacute respiratory failure as the first symptom without significant extremity weakness.
  
  
  RESULTS
  Electromyography of extremities was normal but showed myopathic changes and myotonic discharges limited to axial muscles only. Muscle biopsy confirmed the diagnosis.
  
  
  CONCLUSIONS
  It is essential to examine axial muscles during electromyography if a patient presents with respiratory failure of unclear etiology even if the clinical examination does not show significant weakness in the extremities and electromyographic findings in the extremities are unremarkable.
authors.affiliation: Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA.
authors.forename: Bassel
authors.initials: B
authors.lastname: Salem
authors.forename: Pariwat
authors.initials: P
authors.lastname: Thaisetthawatkul
authors.forename: J Americo
authors.initials: JA
authors.lastname: Fernandes
authors.forename: Rodney D
authors.initials: RD
authors.lastname: McComb
mesh_terms: D000328:Adult; D017668:Age of Onset; D018450:Disease Progression; D004576:Electromyography; D006009:Glycogen Storage Disease Type II / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000473:pathology; D009135:Muscular Diseases / Q000175:diagnosis* / Q000201:enzymology* / Q000473:pathology; D012133:Respiratory Paralysis / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D016896:Treatment Outcome