Huntingtons chorea

Question 1

what is huntintons chorea

Answer 1

Huntington’s chorea is an autosomal dominant genetic condition that causes a progressive deterioration in the nervous system.

Question 2

describe the onset of Huntingtons chorea

Answer 2

Patients are usually asymptomatic until symptoms begin around aged 30 to 50.

Question 3

Huntington’s chorea is a “______________” that involves a genetic mutation in the ____ gene on chromosome _.

Answer 3

Huntington’s chorea is a “trinucleotide repeat disorder” that involves a genetic mutation in the HTT gene on chromosome 4.

Question 4

describe what is meant by anticipation wrt Huntingtons chorea

Answer 4

Huntington’s chorea displays something called 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

Question 5

how might huntingtons chorea present?

Answer 5

usually an insidious progressive worsening of symptoms
typically begins with cognitive, psychiatric or mood problems.
These are followed by the development of movement disorders.

Question 6

give the movement disorders associated with Huntingtons chorea?

Answer 6

Chorea (involuntary, abnormal movements)
Eye movement disorders
Speech difficulties (dysarthria)
Swallowing difficulties (dysphagia)

Question 7

how do we diagnose Huntingtons chorea

Answer 7

Diagnosis is made in a specialist genetic centre using a genetic test for the faulty gene. It involves pre-test and post-test counselling regarding the implications of the results.

Question 8

how do we manage huntintons chorea

Answer 8

No treatment options:
SO:
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

Question 9

give the medications which we can use to control the symptoms of Huntingtons chorea?

Answer 9

Medications that can suppress the disordered movement:

Antipsychotics (e.g. olanzapine)
Benzodiazepines (e.g. diazepam)
Dopamine-depleting agents (e.g. tetrabenazine)