Dementia Flashcards
What are some genes associated with alzheimer’s?
ApoE4 (on chromosone 19)
Amyloid precursor protein gene mutations (Chr 21)
Presinilin 1 (Chr 14) and Presinilin 2 (Chr 1)
alpha-2 macroglobulin mutations (Chr 12)
What results on CSF analysis might suggest AD?
elevated tau and low alpha,beta-42 levels in the CSF
What result on MRI might suggest AD?
a reduction of hippocampus, amygdala and thalamic size
What result on PET or SPECT may suggest AD?
bilateral temporoparietla hypometablism
What are the major characteristics of AD pathology?
gross path: brain atrophy
micro path: senile plaques, neurofibrillary tangles
What are the senile plaques made of?
extracellular deposits of amyloid surrounding dystrophic axons
What are the neurofibrillary tangles made of?
intracellular accumulations of phosphorylated tau protein
What are the medications we use for AD?
acetylcholinesterase inhibitors like donepezil or rivastigmine
NMDA receptor antagonists like memantine (not used at the VA bc it probably doesn’t work)
Vitamin E
What is the average length of time from onset of symptoms to diagnosis in AD? What is the typical life-expectancy after a diagnosis of AD?
about 2-3 years
average duration from diagnosis to nursing home is 3-6 years
average life-expectancy after a diagnosis is 5-10 years
What are the criteria for vascular dementia?
presence of dementia and two or more of the following: onset that is abrupt , stepwise progression, imaging with evidence of strokes, lacunes or extensive WM changes (Binswanger disease)
Describe the typical clinical manifestations of dementia with lewy bodies.
cognitive impairment - particularly with visuospatial perception and visual memory
marked fluctuations in alertness
prominent visual hallucinations in up to 80% of cases
delusions
extrapyramidal symptoms
extraordinary sensitivity to neuroleptics
What is a lewy body?
an eosinophilic intracellular inclusion of alpha synuclein
Where are the lewy bodies found in dementia with lewy bodies vs parkinsons disease?
in dementia they’re found in the cortical neurons in addition to the basal ganglia neurons (unlike in PD where they’re more just in the basal ganglia)
What is the diagnosis in someone who has an inability to look up, dyarthria, dysphagia, extrapyramidal rigidity, gait ataxia and dementia?
progressive supranuclear palsy
What will gross pathology show in progressive supranuclear palsy?
atrophy of the dorsal midbrain, globus pallidus, and subthalamic nuclei
How do we make the diagnosis of Huntington’s diasease?
more than 40 CAG repeats in the HD gene on chromosome 4
What does pathology show in Huntington’s disease?
severe destruction of the caudate and putamen (striatal GABA-ergic neurons) and loss of neurons in layer 3 of the cerebral cortex
How does frontotemporal dementia typically present?
personality changes early in the disease, then memory later
Describe the typical presentation of CJD.
rapidly progressive dementia with pyramidal signs, MYOCLONUS, cerebellar or extrapyramidal signs
What will be seen on the EEG in CJD?
periodic sharp waves
What might MRI with DWI show in CJD?
evolving cortical and basal ganglionic abnormalities
What do we look for in the CSF for diagnose CJD?
protein 14-3-3
What is the expected life span after a CJD diagnosis?
1 year
What are some of the ways HIV can affect the CNS?
the virus can produce an encephalitis by itself
can also predispose individuals to other CNS infections like toxoplasmosis, tuberculosis, syphilis, and JC virus
can also cause a dementia by itself
What is the management for HIV-associated dementia complex?
HAART
