Degenerative and demyelinating diseases Flashcards
1
Q
Alzheimer’s disease (AD)
A
- Affects memory, perception, judgement and visual/spatial
- Due to changes is hippocampus (first to change), frontal, and parietal lobes
- Bilateral atrophy of gyro and widening of sulci
- Ex-vacuo hydrocephalus due to loss of tissue
- Nucleus basalis meyret loss (main source of Ach in CNS)
- Due to abnormal aggregation of tau proteins (a normal component of microtubules) into insoluble neurofibrillary tangles (intracellular, alpha helices)
- Also from neuritic plaques: extracellular accumulations of amyloid-beta protein forming amyloid fibrils
2
Q
Pick disease
A
- Mostly frontal and temporal lobes affected
- There is personality changes, reduced judgement, aphasic/trouble with words (can’t speak properly)
- Due to cytoplasmic aggregates of abnormally spliced tau
3
Q
Huntington disease (HD)
A
- Affects the basal ganglia, the caudate (flattened), outer walls of ventricle (flattened), and cortex (shrinks)
- Sx include depression, dementia, chorea, personality changes
- On CT and PET you see both loss of tissue and brain activity
- There is loss of grey matter only, along w/ reactive gliosis
- Characteristics: “milk maid” grip, high incidence of family history, triple codon repeats accelerate onset of HD
4
Q
Parkinson disease (PD)
A
- Affects the catecholaminerigc neurons in the substantia nigra (DA neurons)
- There is dorsal motor nucleus of X and cortical loss
- Histologic feature: lewy body (alpha-synuclein)
5
Q
Amyotrophic lateral sclerosis (ALS)
A
- Affects CST, motor cortex, cranial nerve motor neurons (UMN lesions), anterior horn cell loss (LMNs), and spinocerebellar neurons
- Usually see UMN lesion Sx (increased reflexia)
6
Q
Multiple sclerosis (MS)
A
- Oligodendrocytes are primarily targeted, some of the damage done is reversible
- Random loss of myelin, heavy involvement of optic nerve
- Can see perivascular macrophages and T cells
- Also have oligoclonal bands in blood samples
