Movement disorders Flashcards
akinetic-rigid syndromes
slowed movement with increased muscle tone e.g. parkinsons
dyskinesias
added uncontrollable movements e.g. essential tremor
idiopathic parkinson’s disease pathophysiology
progressive depletion of dopamine-secreting cells in the substantia nigra = less dopamine alone non-striatal pathways = messed up regulation of movement by basal ganglia
what causes the loss of dopamine secreting cells from the substantia nigra in PD?
abnormal accumulation of alpha synuclein bound to ubiquitin which forms cytoplasmic inclusions called Lewy bodies
aetiology PD
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
clinical features PD
rest tremor rigidity bradykinesia (slow movements) akinesia shuffling gait these features usually more prominent on one side
non motor features may predate motor features in PD. What are they
neuropsychiatric symptoms
sleep disorders
drooling saliva, XS sweating, dysphagia, constipation
fatigue and weight loss
cause of death in PD
bronchopneumonia
investigations PD
diagnosis clinical
drugs PD
- 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
other rx PD
physio - gait / prevent falls
selective serotonin reuptake inhibitors are the rx of choice for depression
what is chorea
continuous flow of jerky, quasi-purpose movements, flitting from one part of the body to another
huntingtons disease
rare autosomal dominant condition
symptoms HD
relentlessly progressive course of chorea & personality change preceding dementia & death
begins middle age
cause of HD
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)
rx HD - non pharm
genetic counselling for family members
S+L therapy and occupation therapy
regular exercise
rx HD - pharm
no rx arrests disease
antidepressants: fluoxetine, amitriptyline
mood stabilisers - carbamazepine
chorea suppression - antipsychotics e.g. olanzapine
Multiple sclerosis
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
epidemiology MS
begins in early adulthood
more common in F
aetiology MS
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
pathology MS
inflammation, demyelination & axonal loss
plaques = perivenular (around a vein) and like CNS sites: optic Ns, brainstem, cervical spinal cord
peripheral nerves never affected
clincal features MS
young adult
2 or more episodes of CNS dysfunction followed by remission where symptoms resolve to some extent
3 common characteristic presentation of relapsing and remitting MS
optic neuropathy
brainstem demyelination
spinal cord lesions
optic neuropathy
characteristic of relapsing MS
inflammation of optic N = blurred vision and unilateral eye pain
