9- dementia

Question 1

what diseases to exclude before diagnosing dementia

Answer 1

hypothyroidism, hypercalcaemia, B12 deficiency, normal pressure hydrocephalus, delerium

Question 2

macroscopic and microscopic features of alzhimers disease

Answer 2

macro

• global cortical atrophy
• sulcal widening
• enlarged ventricles

micro

• plaques formed of amyloid beta
• tangles formed of hyperphosphorylated tay

Question 3

how do plaques form

Answer 3

if amyloid precursor protein is broken down by beta secretes it forms insoluble peptides. these accumulate outside the cell and form beta amyloid plaques

Question 4

effect of beta amyloid plaques

Answer 4

• fill space between neurones causing reduced signal transmission
• inflammatory response causes neuronal death
• amyloid angiopathy when deposited around blood vessels. these weakened blood vessels can bleed

Question 5

where are plaques and tangles located

Answer 5

plaques- outside neurone

tangles- inside neurone

Question 6

effect of alzhimers disease on tau proteins

Answer 6

beta amyloid plaques induce hyperphosphorylation of tau proteins. this causes a change in shape of the tau proteins. can no longer support neuronal cytoskeleton, causing neuronal death.

Question 7

which gens cause alzhimers

Answer 7

PSEN1/2 mutation causes mutation of gamma secretase

Question 8

treatment alzhimers

Answer 8

acetylcholinesterase inhibitors, glutamate receptor antagonist (memantine)

Question 9

what causes lewy body dementia

Answer 9

• misfolding of alpha synuclein protein.
• these aggregate into lewy bodies
• deposit in cortex and substantia nigra

Question 10

cognitive and parkinsonian symptoms lewy body

Answer 10

cognitive- hallucinations, depression, REM sleep disorders

parkinsonian- bradykinesia, resting tremor, stiffness

Question 11

treatment Lewy body

Answer 11

levodopa (dopamine analogue)

Question 12

cause of frontotemporal dementia

Answer 12

aggregated proteins and tau protein hyperphosphorylation causing frontal and temporal love degeneration

Question 13

MRI frontotemporal dementia

Answer 13

unilateral frontal/temporal atrophy

ventricle enlargement

Question 14

causes delirium

Answer 14

Drugs
Epilepsy
Liver failure/low o2
Infection
Retention of urine/faeces
Intracranial 
Uraemia
Metabolism

Question 15

hyperactive vs hypoactive delerium

Answer 15

hyperactive- agitated/aggressive/delusions

hypoactive- drowsy/withdrawn

Question 16

differences between dementia and delirium

Answer 16

differences in delirium: sudden onset, fluctuating, altered consciousness, reversed sleep wake cycle, altered attention