6. Cognitive disorders Flashcards
What are the 2 main types of cognitive disorders?
Delirium and dementia
What are the symptoms of tertiary syphillis? (4)
Tremor, EPS, frontal dizziness, sluggish pupillary reflex
How can tertiary syphillis be diagnosed?
VDRL test (venereal disease research lab) test
Difference b/w delirium and dementia?
Delirium = waxing and waning change in pt’s level of consciousness
Dementia = impairment of memory and other cognitive fxs (language, behavior, personality) WITHOUT alteration in level of consciousness
What are some other terms that refer to delirium? (5)
- Encephalopathy
- Acute organic brain syndrome
- Acute confusional state
- Acute toxic psychosis
- ICU psychosis
What are causes of delirium? AEIOU TIPS
- Alcohol/drug toxicity or withdrawal
- Electrolyte abnormality
- Iatrogenic (ex. anticholinergics, benzo, antiepileptics, blood pressure meds, insulin, abx, antiparkinsonians)
- Oxygen hypoxia (bleeding, central venous, pulmonary)
- Uremia/hepatic encephalopathy
- Trauma
- Infection
- Poisons
- Seizures (postictal), Stroke
What are the two typical symptoms of delirium?
Visual hallucinations (perceptual disturbance) and short attention span
What is the most common finding in delirium?
Impairment in recent memory
What is the difference in EEG in delirium and dementia?
Delirium = EEG changes (fast waves or generalized slowing) Dementia = no EEG changes
What is the most common form of dementia?
Alzheimer’s (50-70%)
What’s the 2nd most common form of dementia?
Vascular dementia (15-25%)
What should you do if a pt presents w/ dementia but has a normal CT scan?
Order complete metabolic panel and MRI
What is dementia with stepwise increase in severity + focal neurological signs?
Multi-infarct dementia
What is dementia + cogwheel rigidity + resting tremor?
Lewy body dementia or Parkinson
Dementia + gait apraxia + urinary incontinence + dilated cerebral ventricles?
Normal pressure hydrocephalus
Dementia + obesity + coarse hair + constipation + cold intolerance?
Hypothyroidism
Dementia + diminished position and vibration sensation + megaloblast on CBC?
Vit B12 deficiency
Dementia + tremor + abnormal LFTs + Kayser-Fleischer rings?
Wilson disease
Dementia + diminished position and vibration sensation + Argyll Robertson Pupils (Accommodation Response Present, response to light absent)
Neurosyphilis
What is considered dysfunction on mini-mental state exam?
Less than 25 (30 is perfect score)
What is the diff. b/w delirium and dementia in terms of symptoms throughout the day?
Delirium = symptoms fluctuate (often worse at night) Dementia = symptoms stable throughout day
What is the risk factor for a 1st deg relative of an Alzheimer’s pt to get Alzheimer’s?
4fold increase
What is the molecule that is reduced in Alzheimer’s?
Ach (due to loss of noradrenergic neurons in the basal ceruleus and loss of choline acetyltransferase - required for ach synthesis)
What are the Alzheimer genes (3)?
Presenelin 1, Presenelin 2, APP (amyloid precursor protein)
What % of cases of Alzheimer’s are due to genetic abnormalities?
5%
What is the major susceptibility gene in Alzheimer
Apolipoprotein e4 (APOe4) - homozygous have 50-90% chance of developing dementia by age 85
What other conditions have senile plaques and neurofibrillary tangles? (2)
Down syndrome and normal aging
What is the amyloid cascade hypothesis?
Excess of AB peptides (either by overproduction or diminished clearance)
What postmortem finding correlates with severity of dementia?
Neuritic plaques (NOT neurofibrillary tangles)
What pharmacotherapy can be used with mild-moderate Alzheimer disease?
Cholinesterase inhibitors
ex. donepezil (Aricept), Tacrine (Cognex), rivastigmine (Exelon), galantamine (Razadyne)
What pharmacotherapy can be used with moderate-severe Alzheimer disease?
NMDA antagonists
ex. Memantine (Namenda)
What is a typical finding on CT of a pt w/ vascular dementia?
Multiple small lacunar infarcts (small vessel disease)
A stroke to which area of the brain can lead to symptoms of schiz, BP1 disorder, and depression?
Frontal lobe
What is the gender prevalence of vascular dementia?
M>W (2 times)
What are 4 risk factors for vascular dementia?
- Stroke
- DM
- HTN
- APOe4
Which dementia shows “step-wise” loss of function?
Vascular dementia (as microinfarcts build up)
What is the treatment for vascular dementia?
No cure or truly effective tx
- cholinesterase inhibitors sometimes successful
- antiHTNs to prevent onset of vascular dementia
What is the pathogenesis of Lewy Body dementia?
Lewy bodies and Lewy neurites (pathologic aggregation of alpha-synuclein) in the brain
What is the primary brain location of Lewy Body dementia?
Basal ganglia
What are core features of Lewy body dementia? (4)
Waxing and waning
Parkinsonism
Visual hallucinations
Sensitivity to neuroleptics
What is the diff. b/w Lewy body dementia and Parkinson disease dementia?
Lewy body = onset of dementia within 12 months of parkinsonism symptoms
Parkinson disease dementia = onset of dementia AFTER 12 months of parkinsonism symptoms
Which is more closely linked to the clinical symptoms of lewy body dementia? Lewy neurites vs. Lewy bodies?
Lewy neurites
What tx can be used for lewy body dementia to help with visual hallucinations?
Cholinesterase inhibitors
How does psychostimulants, levodopa/carbidopa, and dopamine agonists help pts with lewy body dementia?
Helps improve cognition, apathy and psychomotor slowing
What is the progression of pick disease (frontotemporal dementia) compared to Alzheimer?
More rapid progression to death
Where is the gene mutation found in familial pick disease?
Progranulin or MAPT gene
What is the typical age presentation of pick disease?
45-65 yo
What is the brain pathology of pick disease?
- Marked atrophy of the frontal and temporal lobes
- Neuronal loss, microvacuolization, and astrocytic gliosis in cortical layer II
What are some clinical manifestations of pick disease?
- profound changes in personality and social conduct
- disinhibited verbal, physical, and sexual behavior
- Echolalia, overeating, oral exploration of inanimate objects
- lack of emotional warmth, empathy, or sympathy
- cognitive deficits in attention, abstraction, planning, and problem solving
- memory, language, and spatial fxs well preserved
How does anticholinergic and antidepressants help in pts with pick disease?
Helps improve behavioral symptoms but not cognition
What are the risk factors for HIV associated dementia? (3)
- duration of illness
- low CD4
- high viral loads
What are the movement disorders seen in Huntington?
- choreiform movements (dancelike)
What are some psychiatric manifestations seen in Huntington? (3)
- depression, psychosis, alcoholism
What is shown on MRI of Huntington pts?
Caudate atrophy (sometimes cortical atrophy too)
What is the pathology of Huntington?
Trinucleotide repeat on short arm of chromosome 4
What is lilliputian hallucination?
Sensation that objects appear very small
What brain structure is affected in Parkinson disease?
Substantia nigra (neuronal loss)
What % of Parkinson pts develop dementia?
30-40%
What is the pathogenesis of Creutzfeldt-Jakob disease? (CJD)
Accumulation of abnormal forms of prions (proteinaceous infectious particles that are normally expressed by healthy neurons)
What is the definitive dx of Creutzfeldt-Jakob disease?
Pathological demonstration of spongiform changes in brain tissue (brain bx)
What are some clinical features of CJD? (5)
- Myoclonus (sudden spasms of muscles)
- Cortical blindness
- Ataxia, pyramidal signs, EPS
- Muscle atrophy
- Mutism
What are early signs of CJD? (3)
Personality changes, immature behavior, paranoia
What is the progression of CJD?
Rapid progression to stupor, coma, death (from months to few yrs)
What are some other prion diseases? (4)
- kuru
- Gerstmann-Straussler syndrome
- fatal familial insomnia
- bovine spongiform encephalopathy (mad cow disease)
What are the 3 symptoms of NPH (normal pressure hydrocephalus)?
3Ws
- wobbly = gait disturbance
- wet = urinary incontinence
- wacky = dementia
What is the brain findings of NPH?
Enlarged ventricles w/ increased CSF pressure
