Dementia and associated disorders Flashcards
________ is a degenerative disease of the frontal and anterior temporal lobes (spares parietal and occipital lobes), and is characterized by round aggregates of Tau protein in neurons of the cortex
Pick disease, which is a subtype of Frontotemporal Lobar Degeneration FTLD-Tau type (there also exists a FTLD-TPD-43 type)
In Pick’s disease, you will see rounded aggregates of Tau (pick bodies), which is in contrast to Alzheimer’s Disease that has Tau forming in the shape of the neurons (neurofibrililary tangles)
Behavioral and language symptoms arise early; eventually progresses to dementia
_________________presents with alterations in personality, social behavior, and/or language. There will be progressive deterioration of these faculties and eventual progression to a global dementia.
Frontotemporal dementia (Pick disease)causes pronounced atrophy of the frontal and temporal lobes with sparing of the posterior 2/3 of the superior temporal gyrus:
- Frontal lobe degeneration leads topersonality changes, abulia, and disinhibition.
- Temporal lobe degeneration leads toimpaired understanding of language.
Certain mutations predispose to early-onset Alzheimer diseaseincluding what 3:
- Amyloid β precursor protein (AβPP) gene on chromosome 21
- Presenilin-1 gene on chromosome 14
- Presenilin-2 gene on chromosome 1 (presenillin is part of a complex for gamma-secretase enzymes involved in degrading amyloid beta proteins)
Down syndrome patients almost universally develop _________ by 40 years of age due to the extra copy of chromosome 21 leading to increased expression of _____ gene.
Alzheimer disease
AβPP
AβPP mutations lead to abnormal Aβ production. In addition, metabolizing enzymes like alpha-secretase are unable to degrade proteins leading to formation of neuritic “senile” plaques.
Distinct alleles of the apolipoprotein E (ApoE) gene have different associations with the risk of developing late-onset Alzheimer disease, what are the high and low risk alleles?
ApoE2: decreased risk
ApoE4: increased risk
_________ have an extracellular core comprise of Aβ amyloid with entangled neuritic processes
Neuritic plaques
__________ have intracellular aggregates of fibers composed of hyperphosphorylated Tau protein
Neurofibrillary Tangles
______ is derived from amyloid precursor protein (APP), which is coded on chromosome ____
Aβ amyloid
chromosome 21
APP normally undergoes alpha cleavage; beta cleavage is what results in Aβ amyloid
What is the major class of drug used to treat AD?
Acetyocholinesterase inhibitors (donepezil)
The degeneration of cholinergic cells that project to the cortex from the basal forebrain, especially in the basal nucleus of Meynert is seen in patients with Alzheimer disease.
__________areextracellular β amyloid core that may cause amyloid angiopathy.
Senile plaques
AβPP mutations lead to abnormal Aβ production. In addition, metabolizing enzymes like alpha-secretase are unable to degrade proteins leading to formation of neuritic “senile” plaques.
_______ is anamyloid deposition around vessels leading to lobar intracranial hemorrhage.
Amyloid angiopathy
________areintracytoplasmic proximal dendritic eosinophilic inclusions of actin.
Hirano bodies
___________isatrophy of the hippocampus consisting of small vacuoles within the cell body, each vacuole having a small dense inclusion.
Granulovacuolar degeneration
_______is a depression that mimics dementia with an abrupt onset, moderate memory loss, cognitive problems, no decrease in IQ, and previous psychiatric history (unlike in Alzheimer disease).
Pseudodementia
__________ shows minor forgetfullness, reduced ability to learn new things quickly, no decrease in IQ (unlike in Alzheimer disease), and no disruption of normal life.
Normal aging
__________ has an insidious onset, severe memory loss, cognitive problems, decrease in IQ, and disruption of normal life.
Alzheimer disease
_______ is caused by multiple, small cerebral infarctions usually resulting from cardiovascular disorders such as HTN, or atherosclerosis.
How do you tx?
Vascular dementia, or vascular neurocognitive disorder (NCD).
You will see lacunar infarcts (small holes)
Tx: treat underlying CVD to prevent further infarcts from occurring (anticoags, antihypertensives)
This is the 2nd most common cause of dementia, with symptoms that occur in a stepwise fashion
Vascular dementia
Step wise progression can be seen after CVA
Controlling vascular risk factors will help
Often subcortical predominance (tend to have depression, executive fcn reduced)
What histologic structure is necessary for a diagnosis of Parkinsons Disease?
Lewy bodies must be present in the substantia nigra
Even if you find a loss of pigmentation in the substantia nigra but you do NOT find lewy bodies, then it is not PD
Dementia with Lewy Bodies (DLB) is associated with Lewy bodies being found in what region of the brain?
Cortex (frontal, temporal, limbic, insular cortex)
The finding of lewy bodies in substantia nigra is characteristic of Parkinsons
A stain for what protein is needed to diagnose lewy bodies in lewy body dementia?
alpha-synuclein is used to stain sections of cortex, since lewy bodies are much easier to see in substantia nigra (PD patients).
Lewy Body Dementia (LBD) or Parkinson’s Disease (PD)
Onset of dementia within 12 months of PD diagnosis?
Lewy body dementia
With PD, you see onset of dementia >12mo after PD dx
Lewy Body Dementia (LBD) or Parkinson’s Disease (PD)
Onset of dementia more than 12 months of PD diagnosis?
Parkinson’s Disease and dementia
With Lewy Body Dementia you will see the onset of dementia within 12 months of PD dx
Vivid visual hallucinations are characteristic of Lewy body dementia or parkinsons diseasE?
Lewy body dementia
