Movement disorders

Question 1

akinetic-rigid syndromes

Answer 1

slowed movement with increased muscle tone e.g. parkinsons

Question 2

dyskinesias

Answer 2

added uncontrollable movements e.g. essential tremor

Question 3

idiopathic parkinson’s disease pathophysiology

Answer 3

progressive depletion of dopamine-secreting cells in the substantia nigra = less dopamine alone non-striatal pathways = messed up regulation of movement by basal ganglia

Question 4

what causes the loss of dopamine secreting cells from the substantia nigra in PD?

Answer 4

abnormal accumulation of alpha synuclein bound to ubiquitin which forms cytoplasmic inclusions called Lewy bodies

Question 5

aetiology PD

Answer 5

MPTP - impurity produced during illegal synthesis of opiates
PD is less prevalent in tobacco smokers
Mutations in parkin gene, a-synuclein gene and ubiquitin gene = early onset PD

Question 6

clinical features PD

Answer 6

rest tremor
rigidity 
bradykinesia (slow movements)
akinesia
shuffling gait 
these features usually more prominent on one side

Question 7

non motor features may predate motor features in PD. What are they

Answer 7

neuropsychiatric symptoms
sleep disorders
drooling saliva, XS sweating, dysphagia, constipation
fatigue and weight loss

Question 8

cause of death in PD

Answer 8

bronchopneumonia

Question 9

investigations PD

Answer 9

diagnosis clinical

Question 10

drugs PD

Answer 10

• levodopa (L-dopa, a dopamine precursor) with a peripheral dopa-decarboxylase inhibitor e.g. bensarazide or carbidopa (reduces nausea SE)
• dopamine agonists - prmipexole, rotigotine
• Monoamine oxidase B inhibitor - inhibits the catabolism of dopamine in the brain

Question 11

other rx PD

Answer 11

physio - gait / prevent falls

selective serotonin reuptake inhibitors are the rx of choice for depression

Question 12

what is chorea

Answer 12

continuous flow of jerky, quasi-purpose movements, flitting from one part of the body to another

Question 13

huntingtons disease

Answer 13

rare autosomal dominant condition

Question 14

symptoms HD

Answer 14

relentlessly progressive course of chorea & personality change preceding dementia & death
begins middle age

Question 15

cause of HD

Answer 15

expansion of CAG repeats in the HD gene on chromosome 4 = production of mutant huntingtin protein
loss of neurones in the basal ganglia = depletion of GABA and ACh (not dopamine)

Question 16

rx HD - non pharm

Answer 16

genetic counselling for family members
S+L therapy and occupation therapy
regular exercise

Question 17

rx HD - pharm

Answer 17

no rx arrests disease
antidepressants: fluoxetine, amitriptyline
mood stabilisers - carbamazepine
chorea suppression - antipsychotics e.g. olanzapine

Question 18

Multiple sclerosis

Answer 18

chronic debilitating autoimmune disorder of the CNS in which there are multiple plaques of demyelination within the brain and spinal cord

plaques are disseminated in time and place

Question 19

epidemiology MS

Answer 19

begins in early adulthood

more common in F

Question 20

aetiology MS

Answer 20

inflammatory process in the white matter of the brain and spinal cord mediated by B cells and CD4 t cells
EBV exposure may predispose to MS in genetically susceptible host
antibodies directed against EBV may be redirected to attack CNS myelin

Question 21

pathology MS

Answer 21

inflammation, demyelination & axonal loss
plaques = perivenular (around a vein) and like CNS sites: optic Ns, brainstem, cervical spinal cord
peripheral nerves never affected

Question 22

clincal features MS

Answer 22

young adult

2 or more episodes of CNS dysfunction followed by remission where symptoms resolve to some extent

Question 23

3 common characteristic presentation of relapsing and remitting MS

Answer 23

optic neuropathy
brainstem demyelination
spinal cord lesions

Question 24

optic neuropathy

Answer 24

characteristic of relapsing MS

inflammation of optic N = blurred vision and unilateral eye pain

Question 25

brainstem demyelination

Answer 25

characteristic of relapsing MS

produced dipopia, vertigo, dysphagia, nystagmus

Question 26

spinal cord lesions

Answer 26

characteristic of relapsing MS
sensory symptoms incl numbness and pins & needles due to spinothalamic and post column lesions
spastic parapesis - demyelination cervical and thoracic

Question 27

rx MS

Answer 27

• short courses of steroids - iv methylprednisolone used in relapses to reduce severity
• subcut ß-interferon reduces the relapse rate by one third
• glatiramer acetate - antigenically similar to myelin basic protein - competes for presentation to T cells
• Natalizumab - 2nd line
• Physio and occ therapy

Question 28

investigations MS

Answer 28

MRI brain and spinal cord shows plaques particularly in periventricular region and brainstem - cant see on CT