Background: There have been a few case reports of motor neuron disease in association with Huntington disease (HD).
Objective: To describe a patient presenting with prominent fasciculations, chorea, and possible amyotrophic lateral sclerosis (ALS) in whom genetic testing revealed HD mutation.
Design: Case report.
Setting: University of Texas Southwestern Medical Center, Dallas. Patient A 69-year-old man with chorea and fasciculations.
Interventions: Genetic and electrophysiologic testing.
Main outcome measures: Genetic test result, electrophysiologic test result, and physical examination.
Results: A 69-year-old man with long-standing depression and failing memory presented with muscle twitches of 8 months' duration. He was found to have choreoathetoid movements and distal weakness on neurological examination. Electrophysiologic studies revealed evidence of motor neuron disease. Genetic test showed CAG repeat of 40 on chromosome 4, confirming the diagnosis of HD.
Conclusion: Motor neuron disease can rarely occur in patients with HD and could be one of its presenting features.