Dementia Flashcards
Define Cognition
the mental action of acquiring knowledge and understanding thought, experience and the senses
Rapidly progressive cognitive decline should always lead to suspicion of _______________
CJD (prion disease)
Dementia is early onset if under age ?
65
Who is referred to neurology with dementia vs old age psychiatry?
More than 65 years old with gradual onset dementia and no additional neurology go to old age psychiatry
Less than 65 years old or anyone with unusual features (including rapid speed of onset)/ additional neurology should be referred to neurology
Dementia is a clinical syndrome with multiple causes defined by:
- an acquired loss of higher mental function affecting 2 or more cognitive domains
- being of sufficient severity to cause significant social or occupational impairment
- being chronic and stable (different from delirium which is acute and fluctuating)
List some acute cognitive disorders?
Brain injury/ head injury Stroke Viral encephalitis Transient global amnesia Transient epileptic amnesia
Briefly describe transient global amnesia?
lasts for 4-6hrs (no more than 24hrs!), usually a one off episode, person a bit confused and asking repetitive questions, still aware of themselves and who they are, make a full recovery, not sure of the pathophysiology
Briefly describe transient epileptic amnesia?
associated with temporal lobe seizures that may not be witnessed, asking receptive questions, can carry out complex tasks but doesn’t recall events, responds to anti-epileptic medications
List two subacute cognitive disorders?
functional/ subjective cognitive impairment
prion disease
Describe patient complains in functional/ subjective cognitive impairment?
everyday forgetfulness but patient perceives this as having a great impact on functioning, not unusual forgetfulness e.g. the classic go into a room and forget why there, claims that before they had an excellent memory, mismatch between symptoms reported and actual level of functioning, symptoms don’t match neurodegenerative disorders as they say that some day better than others etc as opposed to a gradual decline
What is the most common human prion disease?
Creutzfeldt-Jakob disease
Describe how prion disease causes cognitive impairment/ dementia?
Misfolded native prion protein (PrPc) can’t be broken down by normal mechanisms so it builds up causing subsequent neurodegeneration. There is a domino effect where once a prion protein misfolds every protein it touches also misfolds
Describe presentation of prion disease?
Causes a rapidly progressive dementia leading to death within six months of onset
How is diagnosis of prion disease made?
marked aggressive presentation, also MRI, EEG and CSF analysis
Most common form of CJD is?
sporadic
List three forms of CJD?
sporadic, iatrogenic, variant
Describe sporadic CJD?
occurs in over 50 yo and thought to be due to spontaneous mutations causing misfolding of the prion proteins
Describe iatrogenic CJD?
can occur as prions are resistant to sterilisation so implants from cadavers for growth hormone or for corneal grafts from those infected could cause the disease, there is an incubation period of several years
Describe variant CJD?
affects young people in 20s and linked to exposure to BSE (mad cow disease causing prion) from contaminated meat
What will all patients with CJD ultimately develop?
spongiform change in the brain