Huntington's disease Flashcards
1
Q
Define Huntington’s disease
A
autosomal dominant neurodegenerative movement
disorder
2
Q
What is Huntington’s due to?
A
It is due to an increase in CAG repeats: <28 is normal; 28-35 runs risk of disease; 40 or more basically guarantees pathology
3
Q
Describe the pathophysiology of Huntington’s
A
- Pathology involves the degeneration of the basal ganglia, specifically the caudate nucleus and putamen. These are input nuclei; inhibitory.
- Because of a loss in inhibition, it results in a lack of coordination, initiation of unwanted movements, and shaky, choreiform characteristics
4
Q
What do more CAG repeats in a person mean?
A
The earlier and more severely the symptoms will present (anticipation)
5
Q
What is the age of onset for Huntington’s?
A
20-40
6
Q
What are symptoms and signs of Huntington’s?
A
- Chorea: choreiform
movements at first - aggressive personality change
- loss in cognitive ability
- dysphagia and speech difficulties
- akinesia and dystonia soon replaces the chorea to become more Parkinsonian in
nature - Psychiatric features include depression, psychosis, delusions, hallucinations, agitation, sleep disturbance and emotional instability
7
Q
Where are the CAG repeats located?
A
On chromosome 4 affecting HTT gene
8
Q
How do you diagnose Huntington’s?
A
- through PCR testing for CAG
repeats, but can be done clinically
(>35 CAG) - Family history
9
Q
What is the treatment/management for Huntington’s?
A
- is MDT and palliative
- Antipsychotics and VMAT2 inhibitors are given
- DA agonist for chorea (tetrabenazine)
