Neuropathology - Degeneration Flashcards
What is demyelination?
preferential destruction of myelin sheath around an axon
What cells are damaged in demyelination?
oligodendrocytes
schwann cells
What cells produce myelin in the CNS?
oligodendrocytes
What cells produce myelin in the PNS?
Schwann cells
What is the importance of myelin?
insulates nerves and allows rapid conduction of electrical impulses along cell membranes
What condition is an example of primary demyelination?
Multiple Sclerosis
Is MS more common in females or males?
2:1 females
How does MS commonly present?
episodes of neurological deficit separated by time and body site.
What are some common manifestations of MS?
visual disturbance
spasticity
speech disturbance
gait abnormalities
MS affects grey matter in the brain - T/F?
False - white matter!
What type of scan is used to diagnose MS?
MRI Scan
What are the main features seen on histology in a patient with MS?
demyelination
inflammation
gliosis
What is dementia?
impairment of previously acquired occupational or social functioning due to acquired cognitive impairment with normal consciousness
Dementia is not always a pathological process - T/F?
False - always pathological
What are the two groups of dementias?
primary
secondary
Name some primary dementias?
AD
LBD
HD
Picks disease
Name some secondary dementias?
vascular
metabolic
infection/trauma
Which is the most common dementia?
Alzheimer’s disease
Which common genetic syndrome carries an increased risk of AD?
Down’s Syndrome - trisomy 21
What macroscopic pathology is seen on the brain?
cortical atrophy widened sulci narrowed gyri dilated ventricles normal brainstem and cerebellum
What microscopic features of dementia are there?
neurofibrillary tangles
B-amyloid plaques
amyloid angiopathy
neuronal loss
What stain is used to show up amyloid protein?
congo red stain
What two types of amyloid protein are there?
AL/AA
What are the hallmarks of Lewy Body dementia?
progressive dementia
hallucinations
fluctuating attention levels
What protein is stained for in the identification of lewy bodies?
ubiquitin
What is the common triad of Huntington’s disease symptoms?
emotional
cognitive
motor disturbance
What is the movement disorder in HD known as?
chorea
When does dementia occur in HD?
later in disease
What is the pattern of inheritance in HD?
autosomal dominant
Which chromosome is the huntingtin gene on?
Chromosome 4p
What is seen on HD histology?
loss of caudate nucleus neurones
reactive gliosis
What is Pick’s disease?
a progressive dementia commencing in middle life characterised by changes in character and social deterioration leading to cognitive impairment
Where is extreme atrophy seen in a Pick’s Disease brain?
frontal and temporal lobe cortices
What are Pick’s cells?
swollen neurons
What are Pick’s bodies?
intracytoplasmic filamentous inclusion
How long will a person usually live after a diagnosis of Pick’s disease?
7 years average (2-10)
Which is the most common secondary dementia?
vascular dementia
What is multi-infarct dementia?
deterioration in cognitive function due to hypoxia induced brain damage as a result of multiple blood clots.
Which cardiovascular conditions are particularly important in multi-infarct dementia?
hypertension
hyperlipidaemia
diabetes
previous stroke
What type of progression is seen in multi-infarct dementia?
stepwise progression
