Degenerative Diseases of the CNS

Question 1

Name two of the main diseases of the CNS

Answer 1

Dementia and parkinsonism

Question 2

Define dementia

Answer 2

It is a syndrome consisting on:
Progressive impairment of multiple domains of cognitive function in alert patient leading to loss of acquired skills and interference in occupational and social role

Question 3

Describe the impact of dementia

Answer 3

• Areas of cognition deteriote, it is not just a memory deficit
• There is history of loss of cognitive function – not due to ability but they can’t process the action
• Can’t maintain same social relationships due to impaired cognitive function

Question 4

Name the causes of dementia with a late onset (65yrs)

Answer 4

• Alzheimer’s
• Vascular*
• Lewy body**
• Other
• Repetitive little strokes, might not even be aware
• *Form of parkinsons – abnormal aggregates of protein that develop inside nerve cells

Question 5

Name the causes of dementia with an early onset (<65yrs)

Answer 5

• Alzheimer’s 
• Vascular 
• Frontaltemporal 
• Other 
   o Toxic (alcohol)
   o Genetic (Huntington’s)
   o Infection (HIV, CJD)
   o Inflammatory (MS)

Question 6

What are three treatable causes of dementia?

Answer 6

• Vit deficiency - B12
• Endocrine - thyroid disease
• Infective - HIV, syphilis

Question 7

What are three conditions which mimic dementia?

Answer 7

• Hydrocephalus
• Tumour
• Depression: ‘pseudodementia’

Question 8

To diagnose dementia, what do you need to find out in the history?

Answer 8

From an independent witness:
• Types of deficit – areas where theyre struggling; memory, getting lost, wandering, failing with finances, change in behaviour (drive, motivation) etc
• Progression
Family history

Question 9

To diagnose dementia, what do you need to find out in the examination?

Answer 9

Cognitive function neurological, vascular

Question 10

To diagnose dementia, what do you need to find out in the lab results in dementia?

Answer 10

• Routine – bloods (not B12 deficient, hypothyroid, screen for HIV), CT/MRI
• Others (for under 65yrs) – CSF, EEG, functional imaging, genetics (biopsy)

Question 11

What is involved in examination of cognitive function in dementia?

Answer 11

• Various domains
• Screening tests
• Neuropsychological assessment

Question 12

What do you look for in the various domains involved in examination of cognitive function in dementia?

Answer 12

• Memory, attention, language, visuospatial,
• Behaviour, emotion, executive function
• Apraxia (can’t do a motor take as you can’t plan it), agnosias (inability to put sensory meaning to something)

Question 13

Name two screening test for cognitive function of dementia

Answer 13

Mini-mental (MMSE) and Montreal (MOCA)

Question 14

Name three clues to diagnosis of dementia

Answer 14

• Type of cognitive deficit
• Speed of progression
• Other neurological signs

Question 15

What are two different types of speed progression in dementia

Answer 15

• Rapid progression (CJD*)
• Stepwise progression (vascular)

*Creutzfeldt-jakob disease (CJD) is a fatal form of dementia caused by a protein found in the brain called prion

Question 16

What is alzheimer’s disease?

Answer 16

Commonest neurodegenerative condition (mean age onset 70yr) which causes temporo-parietal dementia

Question 17

What are the features of dementia caused by alzheimer’s disease (temporo-parietal dementia)?

Answer 17

Temporo-parietal dementia:
• Early memory disturbance
• Language and visuospatial problems
• Personality preserved until later (as it doesn’t affect frontal lobe)
• “Does he/she have the same personality, just more forgetful?”

Question 18

What are the features of frontotemporal dementia?

Answer 18

• Early change in personality / behaviour
• Often change in eating habits (frontal and temporal lobes drive appetite)
• Early dysphasia
• Memory / visuospatial relatively preserved

Question 19

What is speed of progression in vascular dementia?

Answer 19

Stepwise decline (i.e. worsen with each stroke)

Question 20

What is the non-pharmacological symptomatic treatment of dementia?

Answer 20

• Information & support, dementia services
• OT
• Social work / support / respite / placement

Question 21

What is the pharmacological symptomatic treatment of dementia?

Answer 21

• Insomnia
• Behaviour (care with antipsychotics)
• Depression

Question 22

What is the specific treatment of Alzheimer’s (+/- Lewy body dementia)?

Answer 22

• Cholinesterase inhibitors (cholinergic deficit) – prevents break down of ACh in the brain so more is available for communication between brain cells
o Donepezil, rivastigmine, galanamine
• NMDA antagonist (memantine)

Question 23

Is there a specific treatment for frontotemporal dementia?

Answer 23

No

Question 24

What are the treatment measures for vascular dementia?

Answer 24

No good evidence for decrease in vascular risk factors

Question 25

What is parkinsonism and its features?

Answer 25

``` A clinical syndrome with >= 2 of: • Bradykinesia (slowness of movement) • Rigidity (stiffness) • Tremor (shakiness) • Postural instability (unsteadiness / falls) ```

Question 26

What is the pathology in basal ganglia causing parkinsons?

Answer 26

Loss of nerves in the substantia nigra which leads to a reduction in dopamine in the brain. Dopamine plays a role in regulating movement in the body, so a reduction causes the signs that you see in Parkinson’s.

Question 27

What are the causes of parkinson's?

Answer 27

• Idiopathic Parkinson’s Disease dementia with Lewy bodies • Drug induced (i.e. dopamine antagonists) • Vascular parkinsonism (lower-half) • Parkinson’s plus syndrome o Multiple system atrophy – postural hypotension, impotence, incontinence o Progressive supranuclear palsy / corticobasal degeneration

Question 28

How do you get a definitive diagnosis of parkinsons?

Answer 28

Post mortem

Question 29

What are the clinical features of parkinson's?

Answer 29

* Bradykinesia + >= tremor, rigidity, postural instability * No other cause / atypical features * Slowly progressive (> 5-10yrs)

Question 30

What investigation in used for parkinsons?

Answer 30

Functional Imaging: Dopamine Transporter SPECT (Not diagnostic)

Question 31

What is the early treatment of PD?

Answer 31

* Levadopa is a precursor of dopamine, give with carbidopa or benserazide to block the enzymes * CMOT inactivates levodopa, so can use COMT inhibitor (i.e. entacapone) * These drugs are purely symptomatic, no prevention of progression of disease

Question 32

What are drug induced later complications that occur in PD?

Answer 32

* Motor fluctuations – levodopa wears off * Dyskinesias – involuntary movements (levodopa) * Psychiatric – hallucinations, impulse control

Question 33

What are non-drug induced later complications that occur in PD?

Answer 33

* Depression * Dementia * Autonomic: BP, bladder, bowel * Speech, swallow * Balance

Question 34

What is the later treatment of PD?

Answer 34

``` • Prolong levodopa half life: o MAO-B inhibitors o COMT inhibitor o Slow release levodopa • Add oral dopamine agonist • Continuous infusion (apomorphine, duodena) ``` Function neurosurgery (deep brain stimulation) Allied health professional +/- care package