Movement Disorders: Dyskinesias Flashcards
How can you catagorise dyskinesias?
Tremor Dystonia Chorea Myclonus Tics
What is a tremor?
Rhythmic sinusoidal oscilations of a body part.
May be most prominant at rest (resting tremor), with limbs outstretched (postural tremor) or on movement (intention tremor) depending on the underlying cause.
What is dystonia?
Involuntary, sustained muscle contraction, causes twisting movement or abnormal postures.
What is chorea?
Continuous, irregular, jerky or fidgety movements that move from one part of the body to another in an unpredictable fashion.
What is myoclonus?
Brief, shock-like jerks.
What are tics?
Brief, repetitive stereotyped behaviours that can be transiently controlled by the patient, although doing so causes a build up of inner tension until the tic is allowed to occur.
How is an essential tremor characterized?
Characterised by tremor on holding the arms outstretched or on maintaining certain postures (postural tremour).
Tremor minimal at rest and is not associated with any other neurological dysfunction.
Underlying cause is unknown although family history is present in 50%.
How would an essential tremor present?
Upper limb tremor provoked by certain activities such as holding or pouring drinks.
Tremor usually bilateral and may also affect the head (titubation).
May be localised, generalised, constant or intermittent.
Exacerbated by anxiety and patients may notice an improvement after small amounts of alcohol.
How would you treat a patient with an essential tremor?
Treatment often unnecessary.
In individuals with disabling tremor beta blockers and primidone may be helpful.
What is Huntington’s disease?
Progressive neurodegenerative disease inherited in an autosomal dominant fashion.
How might patients with Huntington’s disease present?
Affected individuals typically present between 30 and 50 years of age with personality change (irritability, aggression and loss of interest) and chorea.
Chorea may be subtle at onset and patients may simply appear fidgety.
How does Huntington’s progress?
Chorea becomes more florid and dementia becomes more severe.
Death occurs 10-20 years after symptom onset.
What tests would you perform if you suspected Huntington’s disease?
Genetic testing can diagnose Huntington’s disease in symptomatic individuals and can identify whether unaffected individuals carry the gene.
Further investigations are required in individuals with no family history and in whom genetic testing is negative.
How would you manage Huntington’s disease?
No treatment for Huntington’s disease.
In view of its devastating nature testing raises difficult issues for families. Genetic counselling is vital.
What is Wilson’s disease?
A rare autosomal recessive disorder of copper metabolism.
What is the pathogenesis behind Wilson’s disease?
Results from the accumulation of copper in the liver, brain (particularly basal ganglia) and other organs.
How do individuals with Wilson’s disease present?
Impaired liver function and neurological features, eg: dystonia Parkinsonism Tremor Neuropsychiatric disturbance
What would be found on examination and investigation of an individual with Wilson’s disease?
Kayser-Fleischer rings (copper deposits around the cornea) are seen on eye examination.
Investgations show:
- Low serum caeruloplasmin
- elevated urinary copper
Elevated hepatic copper concentration on liver biopsy confirms diagnosis.
How would you treat Wilson’s disease?
Treatment is with chelating agents such as penicillamine.
What is Sydenham’s chorea?
Unilateral, postinfective chorea that affects children or adolescents.
Describe the pathogenesis and progression of Sydenham’s chorea.
Onset is usually within several weeks of a group A streptococcal infection.
Settles spontaneously over weeks to months.
What is Gilles de la Tourette’s Syndrome?
Comprises multiple motor and vocal tics such as grunting, barking or uttering oscenities.
Often associated with behavioral disturbance, particularly obsessive-compulsive disorder or attention-deficit hyperactivity disorder.
What would be found after examination and testing on a patient with Gilles de la Tourette’s syndrome?
Nothing, diagnostic tests and examination are normal.
How would you manage a patient with Gilles de la Tourette’s syndrome?
Clondine or haloperidol may provide some symptomatic benefit.
