NEUROPATHOLOGY

Question 1

Alzheimers
- gross changes
- histological changes

Answer 1

Gross changes - atrophy, flattened sulci, enlarged ventricles

Histological - neuronal loss, synaptic loss, granulovascular degeneration
- senile plaques (B Pleated)
- neurofibrillary tangles (abnormally phosphorylated tau protein) - specific to ALZHEIMERS
- hirano bodies

Question 2

Alzheimers

• histological changes

Answer 2

neuronal loss, synaptic loss + granulovascular degeneration

• senile plaques (B Pleated)
• neurofibrillary tangles (abnormally hyperphosphorylated tau protein - degenerative taupathies)
• Hirano bodies - rod shaped eosinophilic bodies in cytoplasm of neurons - seen in extracellular space when neuron dies.

Question 3

what diseases do neruofibrillary tangles occur in?
where?

Answer 3

Alzheimers
Down syndrome
Dementia Pugilistica (punch-drunk syndrome)
Parkinson-dementia complex of Guam Hallervorden-Spatz disease
+ the normal elderly.
where? - the entorhinal cortex and the CA1 field of the hippocampus

Question 4

The best neuropathological correlate of decline is the number of ???
marker for this?

Answer 4

synapses
marker for synapses? - antibody to synaptohysin

Question 5

Lewy Body Dementia
how to detect?

Answer 5

Lewy bodies are weakly eosinophilic, spherical + cytoplasmic
In parkinsons in Substantia Nigra, in DLB in many areas of cerebrum - temporal and frontal.

No simple correlation between number of Lewy bodies and cognitive decline.

Antibody to protease ubiquitin can be used to identify LB or staining apha-synuclein antibodies

Question 6

Fronto-temporal dementia
(3 types underlying pathology)
frontal lobe
Picks
Motor neurone

Answer 6

1. Frontal lobe degeneration - most common type, spongiform degeneration, loss large cortical nerve cells.
2. Picks type- atrophy frontotemporal regions, loss of large cortical nerve cells, neuronal pick bodies + pick cells (swollen neuronal cells)
3. Motor neurone Disease type- frontal cortex and hyppocampus, cerebral atrophy less marked.

Behavioural-Variant Frontotemporal Dementia (bvFTD) (Pick’s disease)
Semantic-variant PPA (svPPA)
Non-fluent-variant PPA (nfvPPA)

Question 7

Creutzfeldt-Jakob Disease
sportadic (most common)
Familial
Variant CJD
mri sign for varcjd

Answer 7

• Microscopically- spongiform encephalopathy
  Prior Protein (PrPc) conformed to PrPSc = protease resistant and accumulates in nervous system.
  Identified with immunoperoxidase staining
  Transmitted via corneal transplant, dural grafts + contaminated electrodes.
  MRI SCAN - pulvinar sign = specific for variant CJD

Question 8

HIV pathology
how? which cells?
Biopsy findings?

Answer 8

HIV receptors - CD4+ T lymphocytes are source of CNS infection (trojan horse hypothesis)
Macrophages and microglia most commonly infected - when infected shed viral proteins and release cytokines
Biopsy findings
- infiltration macrophages into CNS
formation microglial nodules
AIDS related dementia + depression most common SEs

Question 9

Schziophrenia
Gross changes

Answer 9

Enlargement of the lateral ventricles (especially temporal horns)
Decreased brain weight
Basal ganglia volume reduction
Planum temporale reversal R>L (normal L>R)

Question 10

Schizophrenia
Histological changes

Answer 10

No evidence for astrogliosis in schizophrenia
reduced cell numbers and size in hippocampus
increased neuronal density
decrease in presynaptic markers.

Question 11

Mood disorders
whats increased on T2 images?
Lithium?

Answer 11

White matter hyperintensities
(WMH) occur particularly in the deep subcortical white matter in excess in bipolar and unipolar mood disorder
WMH = poor prognosis in depression and bipolar
LITHIUM - increases grey matter volume - neurotrophic.

Question 12

Alcoholic brain damage

Answer 12

Wenekes Encephalopathy
- gliosis and small hemorrhages in structures around 3rd ventricle + aqueduct
- Brain shrinkage - loss of white matter. Some = reversible

Question 13

Autism

Answer 13

• Hypoplasia of cerebellar vermis and to some extent the cerebellar hemispheres is documented
• Purkinje cell count in the cerebellum is significantly lower
• Reduced pruning ?increased cortical volume

Question 14

Taupathies

Answer 14

pick disease
Cortical basal degeneration (CBD)
Progressive supranuclear palsy
Multisystem atrophy

highlighted by tau immunostain

Question 15

Ubiquitin

Answer 15

FTLD-TDP
highlighted by ubuiquitin immunostain

Question 16

Synuceinopathies

Answer 16

Lewy body dementias
Parkinsons disease dementia
Pure autonomic failure