Neurodegenerative disorders Flashcards
What are the key points of the Original Peterson criteria for mild cognitive impairment (MCI)?
Memory complaint
With preserved general cognitive function
Intact activities of daily living
New criteria allows for a NON-amnestic variant
What is possible treatment for MCI?
Donepezil, an acetylcholinesterase inhibitor
What are the key points in Alzheimer’s dz dx by DSM 4
1 Memory impairment with aphasia/ataxia/agnosia/disturbed executive function
2 Cognitive deficit
3 Gradual cognitive decline
4 NOT dx in the presence of delirium
What is the first part of the cerebrum to be involved in AD? The last?
First: Entorhinal complex and hippocampus
Last: Occipital
Differentiate Amyloid plaques and Neurofibrillary tangles
AP: Made up of beta amyloid fragments
NT: Hyperphosphorylated tau proteins; Intracellular deposits starting in neurons in the entorhinal cortex and hippocampus
Differentiate the genetics of early onset and late onset AD
late onset: APOE sigma 4
early onset: Familial AD on chromosome 21 (NB: Down’s syndrome)
What drugs may be used for AD?
Ach-esterase inhibitors such as donepezil, rivastigmine and galantimine
Glutamate inhibitor at the NMDA receptor ONLY AS ADD ON TREATMENT FOR MOD TO SEVERE AD
What are the core features of Lewy body dementia?
Fluctuating cognition
Recurrent visual hallucination
Spontaneous parkinsonism
Two of these = probable DLB (dementia with lewy bodies)
How to differentiate diffuse lewy body dementia and parkinson’s dementia
DLB dementia occurring with parkinsonism or within 1 year of onset of parkinsonism
PD dementia occurs much later in a person dx with PD
What is the primary protein that makes up the Lewy body?
alpha synuclein
Rank the variants of frontotemporal dementia according to rate of progression
Fast– Frontotemporal dementia > Nonfluent apahasia > Semantic– Slow
What are microscopic findings of FTD?
Pick bodies: Tau protein deposits within ballooned neurons (PICK CELLS)
There is LOSS OF LARGE PYRAMIDAL cells in the cortical layer III and loss of small pyramidal and non pyramidal cells of layer 2
What motor neuron dz is FTD associated with?
ALS
What diagnosis does high levels of 1-4-3-3 protein support?
Creutzfeldt Jakob dz
The Hachinski criteria is utilized to diagnose?
Vascular dementia
Score of more than or equal to 7 suggests multi-infarct dementia
What is the Binswager syndrome?
Multiple small infarcts in the deep white matter causing dementia– chronic white matter hypoperfusion
What is the routine lab panel to r/o reversible causes of dementia?
BIG THREE
1 Vit B12
2 Thyroid fxn test
3 Depression dx criteria
CT/ MRI scan
Heavy metal screen
Drug screen
RPR for syphillis
What are the sxs of vascular dementia based on the arteries affected?
1 Middle cerebral artery
2 Anterior cerebral artery
3 Posterior cerebral artery
1 Middle cerebral artery: Aphasia and neglect
2 Anterior cerebral artery: Apathy, abulia, akinetic mutism (Apathy)
3 Posterior cerebral artery: Amnesia, anomia, agnosia (Porget)
Why should acetylcholinesterase inhibitors be tried for vascular dementia?
Because of the high frequency of overlap with AD and possible benefit in VaD
What is the triad of Normal Pressure Hydrocephalus?
Dementia
Gait apraxia NO FESTINATION UNLIKE PD!
Urinary incontinence
What is the upper limit or normal opening pressure?
180mmHg
What are the characteristic MRI findings in NPH?
Ventriculomegaly with an Evans ratio of >0.31
What is the ONLY treatment for NPH?
VP shunt
What are the negative and positive phenomena sxs of Parkinson’s dz?
Negative: Bradykinesia, postural instability and freezing
Positive: Resting tremor and rigidity
What is the key pathologic feature in PD?
Lewy bodies in the substantia nigra
Why give carbidopa with levodopa in PD?
Carbidopa and benserazide is a dopa decarboxylase inhibitor preventing the metabolism of L-dopa before it reaches the dopaminergic neurons
What is an example of COMT inhibitor?
Tolcapone
What PD drug increases the risk of gambling and hypersexuality?
Dopamine agonists: Bromocriptine, pergolide, pramipexole, cabergoline, lisuride
Which rugs provide symptomatic relief in early PD?
Dopamine agonists
What drugs inhibit MAO-B thereby inhibiting the breakdown of dopamine?
Selegiline and rasagiline
Where is the primary site for the “dying back phenomenon” of Friedrich ataxia?
Spinal cord and roots
There is loss of neurons and secondary gliosis
What percentage of patient’s with Friedrich ataxia will be wheel chair bound by 45?
95%!
What are the cardinal features of friedrich ataxia?
1 limb and GAIT ATAXIA of cerebellar and sensory type BEFORE 30
2 dysarthria
3 loss of joint position and vibration sense
4 absent tendon reflexes in legs
5 extensor plantar response
What part of the corticospinal tracts are spared in Friedrich ataxia?
down to the cervicomedullary junction
What would be the findings in genetic testing of a patient with Friedrich ataxia?
GAA repeat expansion on chromosome 9
What is the genetic feature of Huntington dz?
CAG repeats on 4p
What would MRI show in Huntington dz?
Cerebral atrophy especially of the caudate and putamen
What is the treatment for essential tremor?
Propranolol (beta 2 receptor antagonism), primidone and diazepam
Gets better with alcohol
What should be avoided in essential tremor?
Caffeine and nervousness
What are the four overlapping syndromes in Multiple systems atrophy?
1 Olivopontocerebellar atrophy
2 Striatonigral degeneration– parkinsonism and pyramidal sign secondary to degenration of neurons in caudate and putamen
3 Shy drager– parkinsonism and dysautonomia
4 Cortical basal ganglionic degeneration – fronto parietal cortical atrophy
