Neurology - Huntington's Chorea Flashcards
What is Huntington’s Chorea?
An autosomal dominant genetic condition that causes a progressive deterioration in the nervous system
A “trinucleotide repeat disorder” that involves a genetic mutation in the HTT gene on chromosome 4.
> 40 CAG repeats will result in HC
What is the genetic pattern of Huntington’s chorea
Autosomal dominant -
Displays genetic anticipation
Anticipation is a feature of trinucleotide repeat disorders.
This is where successive generations have more repeats in the gene, resulting in:
- Earlier age of onset
- Increased severity of disease
Presentation of Huntington’s…
Insidious worsening neurological symptoms
Typically begins with cognitive, psychiatric or mood problems.
Followed then by development of movement disorders:
- Chorea
- Eye movement disorders
- Dysarthria
- Dysphagia
Diagnosis of Huntington’s
Refer to neurology
Genetic testing for the faulty gene
Main focus of management
Currently no treatment options for slowing or stopping progression of the disease
The key to management of the condition is supporting the person and their family.
Effectively breaking bad news
Involvement of MDT in supporting and maintaining their quality of life (e.g. occupational therapy, physiotherapy and psychology)
Speech and language therapy where there are speech and swallowing difficulties
Genetic counselling regarding relatives, pregnancy and children
Advanced directives to document the patients wishes as the disease progresses
End of life care planning
What medications/treatments can be used to alleviate symptoms?
Medications that can suppress the disordered movement:
- Antipsychotics e.g. olanzapine, haloperidol
- Benzodiazepines e.g. diazepam
- Dopamine depleting agents e.g. tetrabenazine
CBT or antidepressants e.g. SSRIs for psychiatric presentations like depression
Prognosis of HC
Progressive condition
Life expectancy is 15-20 years after symptom onset
As the disease progresses patients become more susceptible and less able to fight off illnesses.
Death is often due to respiratory disease (e.g. pneumonia).
