L9 HD Flashcards
(54 cards)
two main categories of movement disorder
hypokinetic and hyperkinetic
what does a hypokinetic movement disorder entail
reduced movement
examples of hypokinetic movement disorders
- Idiopathic Parkinson’s disease
- Progressive Supranuclear Palsy (PSP)
- Multiple System Atrophy (MSA)
- Vascular Parkinsonism
- Drug-induced Parkinsonism
what does a hyperkinetic movement disorder entail
increased movement
examples of hyperkinetic movement disorders
- Tremor
- Chorea (e.g., Huntington’s Disease)
- Tics
- Hemiballismus
- Myoclonus
what was an early name for HD and where did it come from
“Chorea” (Greek for “dance”)—describes the characteristic twisting, writhing, and uncontrollable movements.
what is Huntington’s Disease
an inherited neurodegenerative movemment disorder characterised by chorea
what type of genetic disorder is HD
Autosomal dominant trinucleotide repeat disorder
where is the genetic mutation that causes HD
Chromosome 4
what is the prevalence of HD
5-8 per 100,000
what does autosomal dominant inheritance mean
- Each child of an affected parent has a 50% chance of inheriting the HD gene.
- If a person does not inherit the gene, they will not develop the disease and cannot pass it on.
- If a person does inherit the gene, they will eventually develop the disease.
- One child inheriting the gene does not affect the chances of others inheriting it.
how is HD diagnosed
- Clinical and family history
- Genetic testing
- MRI scan → Shows atrophy of caudate nuclei
typical age of onset for HD
30-55 years
what is the westphal variant of HD
a variant in which onset occurs before age 21
what percentage of HD cases does the westphal variant account for
5%
what does a younger onset of the disease indicate
that the disease may progress more rapidly
what is a common cause of death in people with HD
aspiration pneumonia
what is the survival time for people with HD
15-20 years post-diagnosis (some cases up to 30-40 years)
three types of symtoms which occur in HD
- movement
- psychiatric
- cognitive
movement symptoms in HD
- Chorea → Rapid, involuntary, non-repetitive movements
- Eye movement disorders
psychiatric symptoms in HD
- Depression, agitation, anxiety
- Increased suicide risk
cognitive symptoms present in HD
- dementia
- dysexecutive syndrome
can HD present with parkinsonism features
yes
what do the movement features in HD look like
- Choreiform, irregular, random, and variable movements.
- May appear semi-purposeful.
- Any part of the body may be affected.
- Interruption of voluntary movement by chorea.