Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pathology Term 4 > Week 3 - DEMENTIA > Flashcards

Week 3 - DEMENTIA Flashcards

Alzheimer's, Parkinson's, Multiple Sclerosis, Others

1
Q

What is the commonest neuronal degeneration?

A

Alzheimer’s

  • primary degeneration
  • GLOBAL
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are examples of selective/system primary neuronal degenrations?

A
  • parkinsons
  • huntingtons
  • MND
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are global primary degenerations characterised by?

A

*alzheimer’s, lewy body, fronto-temporal

–> DEMENTIA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is dementia?

A
  • loss of higher cognitive function (ability to process information –> emotions, language) –> things that make us HUMAN
  • preserved consciousness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the limbic system?

A
  • controls emotions and instinctive behaviour

- includes the hippocampus and parts of the cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the hippocampus?

A
  • part of the brain where short-term memories are converted to long-term memories
  • part of the limbic system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the thalamus?

A

-part of the brain which receives sensory and limbic information, processes it, and sends it to the cerebral cortex (COGNITION) –> gives us understanding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why is there an increasing incidence in Alzheimer’s?

A
  • ageing, toxins, diet, pollution ??

- >45% of adults over 85y are demented

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

When does the brain start degenerating?

A
  • after 30yrs

- rapid >70yrs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the most important feature of alzheimer’s?

A
  • recent memory loss (hippocampus)
  • pts. remember past memories (childhood friends, etc.) but cannot remember where they parked their car, what they ate for breakfast, etc.
  • also: aphasia + agnosia + apraxia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is agnosia?

A

inability to interpret sensations and hence recognise things

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is apraxia?

A

speech disorder in which person has trouble saying what he/she wants to say correctly + consistently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is aphasia?

A

impairment of language, affecting production/comprehension of speech and the ability to read/write

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the commonest etiology of alzheimer’s?

A
  • sporadic (90%) >60yrs

- genetic/familial (10%) early

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the commonest genetic association with alzheimer’s?

A
  • trisomy 21 (Downs syndrome)
  • excess APP (amyloid precursor proteins)
  • early alzheimer’s disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the pathology of alzheimer’s and what are the 3 microscopic characteristic features?

A
  • cortical atrophy, limbic, temporal, hippocampus –> DEMENTIA
    1. neurofibrillary (NF) tangles (tau) –> intracellular
    2. neuritic plaques (Abeta amyloid) –> extracellular
    3. amyloid angiopathy around BVs –> narrowing + ischaemia

**tau + amyloid are neurotoxic –> atrophy of neurons + reactive gliosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are neurofibrillary tangles and what is the pathogenesis of them within neurons (intracellular)?

A
  • abnormal clumps of tau protein
  • breakage of normal binding tau protein leads to collapse of microtubules and tau protein clumps –> NF tangles
  • tau proteins normally stabilise the microtubules**
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What stain is used to identify NF tangles?

A
  • nissl stain

- appear as dark spots within neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What enzymes normally breakdown/cleave amyloid precursor protein?

A
  • alpha + gamma secretase

- broken down into 3 recyclable fragments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the pathogenesis of amyloid plaques (extracellular) in alzheimer’s?

A
  • abnormal cleavage (into 2 fragments) of APP due to presence of beta-secretase enzyme
  • A-beta peptides produced –> insoluble + non-digestable
  • over years these A-beta proteins accumulate and form abnormal filaments (amyloid fibrils) –> AMYLOID PLAQUES
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the gross features of alzheimer’s disease?

A
  • atrophy of neuronal tissue (limbic system, temporal lobe + cortex - advanced)
  • dilatation of ventricles (compensatory)
  • narrowing of gyri
  • widening of sulci
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the first sign of alzheimer’s?

A

memory loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Outline progression of alzheimer’s

A
  1. memory loss = 1st sign
  2. confusion, poor judgement
  3. language and thoughts, restlessness, agitation
  4. inability, dependence on others
  5. wt. loss, seizures, loss of bladder + bowel control
  6. infections, groaning, moaning + grunting
  7. death usually occurs from aspiration pneumonia, respiratory failure or septicemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is parkinson’s disease (characteristic triad)?

A

“shaking palsy”

  • tremor
  • rigidity
  • bradykinesia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Damage to what causes parkinson’s disease?

A

damage to nigrostriatal dopaminergic system (movement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the 3 components of the dopaminergic system?

A
  1. nigro-striatal (movement)
  2. mesolimbic/mesocortical (behaviour)
  3. tuberoinfundibular (prolactin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the difference between parkinsons disease and parkinsonism?

A

PD –> primary atrophy of substantia nigra (origin of dopaminergic system)

Parkonsonism –> secondary (drugs, toxins, other dis.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are lewy body inclusions?

A

dopaminergic nerves with alpha-synuclein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the early sign of PD?

A

-diminished facial expressions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the clinical features of PD?

A
  • diminished facial expressions
  • stooped posture
  • festinating gait
  • bradykinesia
  • rigidity of muscles (cogwheel rigidity)
  • fine rolling resting tremors (pill-rolling)
  • micrographia
  • dementia in SOME cases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is it called when dementia arises <1yr of onset of PD (motor Sx.)?

A

Lewy body dementia (LBD) –> PD + AD

32
Q

What are the gross and microscopic features of PD?

A

Gross:

  • atrophy of substantia nigra
  • loss of neuromelanin pigment in substantia nigra

Micro:

  • markedly decreased pigmented neurons
  • lewy bodies in neurons –> rounded inclusion of alpha-synuclein within neurons
33
Q

What is a characteristic finding in diffuse lewy body dementia (DLD) that helps differentiate between just PD or AD?

A

visual hallucinations

  • usually pleasant (e.g animals, etc)
  • not scary
34
Q

What is parkinsonism?

A
  • clinical syndrome
  • “anti-dopaminergic effects”
  • drugs: dopamine antagonists, MPTP toxin in heroin, pesticides
  • NORMAL substantia nigra
35
Q

What is atypical parkisonism and what 3 disorders fall under it?

A

*other neurodegenerative disorders with parkinson features

  1. progressive supranuclear palsy (PSP)
    - tau, nuchal dystonia, falls
  2. corticobasal degeneration (CBD)
    - jerking movement of limbs
  3. multiple system atrophy (MSA)
    - PD + autonomic abnormalities (orthostatic hypotension) + cerebellar atrophy (ataxia)
36
Q

What does selective myelin damage in myelin disorders lead to?

A

axon damage –> defective transmission of impulse

37
Q

True or False?

Grey matter is affected more in myelin disorders

A

False

-white matter as this is where the myelin is stored (AXONS)

38
Q

What are the 2 types of myelin disorders?

A
  1. demyelinating (increased destruction)

2. dysmyelinating (decreased production)

39
Q

What is the commonest demyelinating disorder? and what is the other?

A

Immune –> multiple sclerosis (MS)** commonest!

also:
-metabolic –> central pontine myelinolysis (osmotic; alcohol)

40
Q

How would an MS patient typically present?

A
  • recurrent limb weakness
  • paraesthesia
  • vision abnormalities
  • remission + relapses, progressive damage (no healing) –> death in years
41
Q

What are the gross and microscopic features of MS?

A

Gross:
-multiple soft pink plaques (MS plaques) of demyelination –> commonly around ventricles (periventricular), optic nerve, cerebellum, spinal cord and throughout white matter

Micro: -myelin stain

  • marked loss of myelin around BVs (decreased blue stain) –> perivascular demyelination
  • inflammation
  • lymphocytes
42
Q

What stain is used to detect MS?

A

myelin stain

43
Q

What are the etiological factors for MS?

A
  1. genetic - twins, family, HLA DR2
  2. environment - virus, EBV?
  3. autoimmune - Th1/Th17** PROVED –> inflamm. (IFN-gamma, IL-23, IFN-beta)
44
Q

What is increased in MS pts. CSF?

A

increased IgG in CSF (oligoclonal)

45
Q

What are the 4 MS plaque types?

A
  1. macrophages; clear border
  2. complement; clear border
  3. diffuse; apoptosis
  4. non-apoptotic
46
Q

True or False?

When a pt. comes in with hyponatremia (severe vomiting, dehydration, etc.) it should be corrected rapidly

A

False

  • should be corrected slowly so as to prevent central pontine myelinolysis
  • rapid correction causes myelinolysis in the base of the pons WITHOUT inflammation
47
Q

How does central pontine myelinolysis occur?

A

-2-6 days following RAPID correction of hyponatremia*
OR
-rapid changes in osmolality, alcoholism, malnutrition, etc.

48
Q

What are the features of central pontine myelinolysis?

A
  • rapidly evolving quadriplegia, may be fatal

- locked in syndrome: - fully conscious yet unresponsive patients (vegetative-like state)

49
Q

What are the dysmyelinating disorders?

A
  • vitamin deficiency (B12)
  • infections –> JC virus - PML in immunosuppressed
  • genetic –> leukodystrophy (dysmyelinating)
50
Q

What is the difference between age-related/senile degeneration and alzheimer’s?

A

exactly the same yet occuring at a later age (slow progress)

  • NF tangles/A-beta plaques still present like alzheimers*
  • hippocampus/cerebral cortex affected like alzheimers
51
Q

What is Fronto Temporal Lobre Dementia (FTLD) AKA?

A

Picks Disease

-second commonest dementia following alzheimers

52
Q

What are the subtypes of FTLD?

A

Picks disease
-FTLD-tau (tau deposition) - common

FTLD-U
-ubiquitin deposition (next common)

53
Q

What are the characteristic features of FTLD?

A
  • affects personality, behaviour and SPEECH
  • younger pts.
  • memory NOT affected until late (c.f. alzheimers where memory loss is the first sign)
  • semantic dementia –> progressive language problems
  • aphasia predominate
  • selective frontotemporal degeneration (rest of brain is normal) –> knife blade atrophy*
54
Q

Why is FTLD known as knife blade atrophy?

A

-atrophy is so severe in the frontotemporal lobes that the gyri become v thin and look like knife blades

55
Q

What are the gross + microscopic features of FTLD?

A

Gross:

  • frontotemporal lobe degenration –> knife blade atrophy
  • rest of brain is normal

Micro:-neurons with round intracytoplasmic inclusions - Pick’s bodies (tau protein)

56
Q

What is the difference in the intracellular inclusions in alzheimers vs. FTLD?

A

alzheimers have NF tangles (abnormal tau protein) which appear irregular/tangled; whereas in FTLD the intracytoplasmic inclusions known as Pick’s bodies (also abnormal tau proteins) are rounded

57
Q

What anatomical structures are characteristically degenerated in huntington’s disease?

A

Striatum

  • putamen
  • caudate nucleus

**makes ventricle look OVAL SHAPED

58
Q

What are the features of Huntington’s disease?

A
  • dementia
  • depression
  • choreiform (dance like) movements –> JERKING DEMENTIA
  • writhing (twisting) movements of limbs*

*5th decade, progressive –> death in 15yrs

59
Q

What gene mutation is responsible for huntingtons disease?

A
  • autosomal dominant

- huntington gene on Chromosome 4p - protein huntington

60
Q

What is associated with increased severity of huntingtons disease?

A

excess CAG tandem repeats

61
Q

What is dementia pugilistica?

A
  • punch drunk syndrome boxers –> TRAUMA
  • chronic traumatic encephalopathy
  • progressive dementia, tremor, focal neurological deficits
  • degeneration in septum pellucidum, thinning of corpus callosum and substantia nigra
  • NF tangles + A-beta amyloid accumulation –> SECONDARY ALZHEIMER’S

Muhammad Ali

62
Q

What is vascular dementia?

A
  • multi-infarct dementia –> HTN, DM, AS, etc.
  • varying clinical features (location/size of infarcts)
  • mixed alzheimer and vascular lesions - common
63
Q

What is binswanger disease?

A

small vessel damage –> HTN, DM, etc (vascular dementia)

64
Q

What is the commonest type of MND?

A

ALS

-amyotropic lateral sclerosis

65
Q

Wha are the features of ALS?

A
  • progressive motor neuron loss
  • muscle weakness
  • fasciculations
  • spasticity (UMN lesion)
  • normal sensation (confined to MOTOR neurons)
66
Q

What cells are associated with degeneration of UMN in ALS?

A

Betz cells in motor cortex

67
Q

What vitamin deficiency is responsible for alcohol-associated CNS disorders?

A

B1 (thiamine)

-chronic alcoholics + also seen in pts with malabsorption syndromes

68
Q

What is wernicke encephalopathy?

A
  • thiamine deficiency (chronic alcoholics/malabsorption)
  • ataxia
  • confusion
  • double vision

*mamillary body + 3rd ventricle haemorrhage

69
Q

What is Korsakoff psychosis?

A
  • thalamus
  • memory loss with confabulations (pt. tries to make up bits of stories due to inability to remember actual story)
  • hallucinations
70
Q

What CNS features are associated with chronic alcoholism?

A
  • wernicke encephalopathy
  • korsakoff psychosis
  • cortical atrophy
  • central pontine myelinolysis
  • atrophy of vermis of cerebellum –> ataxia
71
Q

What does B12 deficiency cause with regards to CNS features?

A
  • subacute combined degeneration of cord (SCDC)
  • both ascending + descending tracts (motor + sensory)
  • spastic ataxia
  • lower limb numbness
  • tingling
72
Q

What vitamin deficiencies can cause neuropathies?

A

B12, B1 (thiamine), B2, B6, E

73
Q

What is the difference between MS and MND?

A

MND:

  • progressive
  • bilateral demyelination
  • increased in males

MS:

  • recurrent/episodic
  • irregular, patchy demyelination
  • increased in females
74
Q

What is the pathogenesis of MS?

A

autoimmune condition –> Th1 + Th17 cells against myelin

*IgG in CSF (oligoclonal antibody)

75
Q

What is Lhermitte’s sign?

A
  • shock like sensation that travels down the neck down the spinal cord
  • clinical finding in MS pts.

Pathology Term 4 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions