Neuropathology Flashcards

Question

Multiple sclerosis pathology

Answer 1

Mediated by: 1. T helper lymphocytes • React with myelin antigens and secrete inflammatory cytokines (IFN) 2. Macrophages • Activated by IFN, prominent is MS lesions 3. B-lymphocytes • Periphery of lesions, role is unknown

Answer 2

• Chronic disease • Episodes of exacerbation and remission of neurological symptoms • Sensory abnormalities • Loss of sense of touch, tingling, vision • Motor abnormalities • Muscle weakness, unsteady gait, uncoordination of movements, sphincter abnormalities • Unpredictable course of disease developmen

Answer 3

• Unknown etiology • Dementia: progressive loos of cognitive functions; functional decline (loss of memory predominates) • Familial AD 5-10% of all cases • Genetic factors: changes on chromosome 21 and 19 • Mutation in apolipoprotein E4 (3% of population) • 3 genes: PS1, PS2 and APP • Sporadic AD • Disease of older people (>65 years)

Answer 4

Gross examination • Brain appears atrophic; narrowing of gyri (folds/ridges), widening of sulci (grooves) • Frontal and temporal cortical atrophy Histological changes: • Most prominent in cortex • Neuritic (senile) plaques • Neurofibrillary tangles

Answer 5

1. Tangles: twisted fibers of hyperphosphorylated tau that builds up within cells 2. Beta-amyloid plaques: clusters of protein fragments that build up between nerve cells

Answer 6

Non-amyloidogenic pathway: APP is cleaved by alpha secretase then gamma secretase Amyloidogenic pathway: APP is cleaved by beta secretase then gamma secretase, resulting in amyloid-beta

Answer 7

Diabetes, midlife hypertension, obesity, physical inactivity, depression, smoking, low educational attainment

Answer 8

• Pathology and mechanisms of neurodegeneration in metabolic disease • BACE1 and Alzheimer's disease (obesity and high-fat diet leads to increased BACE1 activity)

Answer 9

• Subcortical neurodegenerative disorder • Typically affects the elderly • Causes unknown • Decreased number of dopaminergic neurons in substantia nigra • Disturbances of movement, primarily tumor, rigidity, bradykinesia, postural instability

Answer 10

Etiology unknown Gross examination • Substantia nigra appears pale Histological characteristics: • Loss of melanin-rich dopaminergic neurons • Presence of Lewy bodies (alpha-synuclein) Clinical features: • Tremor or twitching of muscles • Instability while walking • Depression, dementia (10%)

Answer 11

• Etiology: Autosomal dominant neurodegenerative disease (HTT gene on chromosome 4) • Epidemiology: 1 in 20 000 people • Pathology: Atrophy of cortex, subcortical nuclei; most prominently in caudate, putamen • Clinical features: involuntary, gyrating movements, progressive dementia Nonspecific histological changes include • Atrophy • Degeneration • Loss of neurons • Reactive gliosis • First symptoms do not appear before midlife • Most become mentally incapacitated by 50 to 60 years old

Answer 12

• Etiology: unknown • Familial form of ALS (~10% of patients) due to mutation in copper-zinc superoxide dismutase (SOD1) • Motor weakness, progressive wasting of muscles in extremities (small hand muscles) • Fasciculations (involuntary twitching) • Slurred speech, by intellect not affected Pathology: • Loss of motor neurons in spinal cord, midbrain, cerebral cortex • Loss of lateral cerebrospinal pathways in spinal cord (muscle atrophy) • Incurable, progressive disease; leads to death over a few year

Answer 13

• Rare, ~2% of all cancer deaths • Brain tumours = high mortality rate • Prominent in younger ages • Histologically classified as benign or malignant • Death is due to compression of vital centers of the brain

Answer 14

• Tumour of glial cells – 75% • Tumours of neural cell precursors – 2% • Tumours of the meninges – 15% • Tumours of the cranial and spinal nerves – 5%

Answer 15

• Solid cerebral tumours in adults • Cystic cerebellar tumours in children • Composed of relatively well-differentiated astrocytes • Progress into lesions; histologically indistinguishable from glioblastoma multiforme

Answer 16

• Most common CNS tumour • Peak incidence: 65 years • Lateral hemispheres Highly variegated gross appearance • Parts of the tumour are necrotic, yellow • Parts are hemorrhagic red; parts are white • Irregularly shaped • Poorly demarcated • Butterfly-like appearance Histological characteristics • Highly anaplastic astrocytic cells • Fetal appearance to cells, or enlarged, bizarre shaped, or multinucleated cells with well developed cytoplasm • Numerous mitotic figures • Proliferative changes in blood vessels Highly malignant

Answer 17

• Occur in cerebral hemispheres • More common in middle-ages adults • Appear well circumscribed, partially cystic, calcified • Histologically, well-differentiated oligodendroglia cells • Possible progression to glioblastoma multiforme

Answer 18

• Children: ventricles • Adults: spinal cord • Ependymoma of filum terminale • Tumour cells line papillary structures or form rosettes

Answer 19

• Arise from cells that make up the meninges • Mostly benign • Located in midline at base of brain, along spinal cord • Cause epileptic seizures or motor deficits • Excellent prognosis