title: Chorea-acanthocytosis presenting as motor neuron disease.
abstract: BACKGROUND
  Chorea-acanthocytosis (ChAc) is a rare autosomal recessive disease characterized by involuntary movements, seizures, cognitive changes, myopathy, and axonal neuropathy.
  
  
  METHODS
  We report a patient who presented with gait impairment and dysarthria. Clinical and neurophysiological assessment disclosed upper and lower motor neuron signs suggestive of motor neuron disease (MND).
  
  
  RESULTS
  Later observation of involuntary movements prompted further investigation. Acanthocytes were identified, and the patient's chorein level was low. Genetic studies identified a novel double heterozygous mutation of the chorein gene involving an exon-stop mutation associated with another mutation that can affect the normal splicing of the RNA.
  
  
  CONCLUSIONS
  We speculate that this genetic mutation could cause the atypical presentation. ChAc should be included in the differential diagnosis of atypical MND.
authors.affiliation: Department of Neurosciences, Centro Hospitalar Lisboa Norte, Hospital Santa Maria, Avenida Professor Egas Moniz, 1648-028 Lisboa, Portugal.
authors.forename: Dulce
authors.initials: D
authors.lastname: Neutel
authors.forename: Gabriel
authors.initials: G
authors.lastname: Miltenberger-Miltenyi
authors.forename: Ines
authors.initials: I
authors.lastname: Silva
authors.forename: Mamede
authors.initials: M
authors.lastname: de Carvalho
mesh_terms: D003072:Cognition Disorders / Q000209:etiology; D056344:Executive Function / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000503:physiopathology*; D054546:Neuroacanthocytosis / Q000150:complications / Q000175:diagnosis*