Huntington disease (HD) is a genetic, autosomal dominant, neurodegenerative disorder characterized clinically by disorders of movement, progressive dementia, and psychiatric and/or behavioral disturbance. In 1872, George Huntington, MD, presented a disease featuring “hereditary nature, adult onset, chorea, mind impairment,” and “with a tendency to insanity and suicide.” Although Huntington was not the first to describe this “dancing mania,” his account was so comprehensive that he received international recognition. In the following 128 years, HD has inspired thousands of research papers in which elucidation of this unrelenting neurodegenerative disorder has been attempted.
The progressive nature of the disorder, the variation in symptoms, and the complexity of diagnosis and treatment is well portrayed in a case study published by Lipe and Bird. They reviewed clinical and genetic features in 34 cases of late-onset Huntington disease.
Among the cases reviewed was a 74-year-old male who presented with mild chorea, memory problems, and anxiety at the age of 61 years. Though his family had no known history of HD, a number of family members were believed to have been afflicted by dementia, a staggering gait, emphysema, and Parkinson disease. Genetic testing revealed 43 CAG repeats in the HD gene. His motor and cognitive function deteriorated over several years following diagnosis. Mild depression progressed to severe depression and suicidal thoughts, followed by psychosis including delusions and hallucinations, requiring multiple psychiatric hospitalizations.