| Alzheimer Disease
| Vascular Dementia
| Frontotemporal dementia
| Huntington's Disease/Chorea
| Dementia with Lewy bodies
| Creutzfeldt Jakob disease
| Behavioural and Psychological Symptoms of Dementia
The disease is named after George Huntington, a doctor of Ohio who published a paper in 1872 based on observations of patients in the East Hampton's, Long Island. The disease could be traced back to a family who had emigrated to the US in 1630 from a small Anglian town in Suffolk, England. If interested read the excellent "Saturday" by Ian McEwan which features a character with Huntington's Chorea.
Rhythmic twirl of wrist
Hints at cruel genetic twist
If child’s path trails parent’s fate
Younger would anticipate Link to author
- Autosomal dominant inheritance
- Choreiform movement disorder in patient aged 30-50
- Cognitive issues are more disabling than chorea
- There is often a family history
- The Mutant HTT gene is at 4p.16.3 and encodes the protein *huntingtin*
- Disease is almost certain with expanded (over 42) CAG trinucleotide repeats.
- CAG (cytosine-adenine-guanine) codes for glutamine
- The translated result is long tracts of glutamine residues
- Main structures affected are the caudate and putamen of the basal ganglia
- Paternally inherited disease may come on earlier and produce a variant with a Parkinsonian picture in childhood
There is a juvenile form of the illness which affects children and young adults under 21 at the point of diagnosis in which Rigidity, spasticity and dystonia are seen early
- Restless and fidgets, extra movements proceeding over time to chorea
- Slowness of movements eventually and chorea eventually declines
- Late disease has Rigidity, spasticity and dystonia but this is seen much earlier in those with childhood onset in which they are often
present from the beginning
- Onset at earlier age with each generation - anticipation
- Difficulty multitasking unable to organise and concentrate and prioritorise
- Subcortical dementia and epilepsy is also a feature
- Increased blink frequency (opposite of Parkinson's disease)
- Slow eye movements, balance problems, late stage dysphagia
- Psychiatric features include mood swings, anger and poor self-control.
- Obsessive compulsive and even psychotic episodes, depression, anxiety
- Episodic anger and irritability, impulsive
- There is a Westphal variant which demonstrates increased rigidity and parkinsonism and is commoner in children
- FBC, U&E, LFTs
- CT/MRI shows decrease in size of caudate and putamen.
- PET scan shows decreased metabolism in an anatomically normal caudate in early disease
- Post mortem studies show significant atrophy of both the cerebral cortex and the corpus striatum.
- There is significant cell loss in the caudate and putamen.
- Genetic testing is now available before the onset of symptoms - ethical questions. Testing is only available at regional genetics clinics, which are
located throughout England and Wales. GPs can arrange a referral.
For more information go to www.hda.org.uk
- Sydenham's chorea
- Wilson's disease
- Management largely supportive and genetic counselling for the family affected
- Treatment of the chorea can involve Haloperidol [US Haldol], Sulpiride and dopamine depleting drugs such as Tetrabenazine to try and induce parkinsonism which might be worse than the chorea
- SSRI's may be useful to treat depression and Sodium Valproate and Carbamazepine may help as mood stabilisers.