Microbiology 9 - Prion disease

Question 1

Describe some possible symptoms of prion disease

Answer 1

Ataxia
UMN weaknesses
Nystagmus 
Limb spasticity 
Hyperreflexia
Paraesthesia 
Tremor
(all neuro symptoms!)

Question 2

What marker of Creutzfeld Jacob Disease may be identified in CSF?

Answer 2

14-3-3 protein

Question 3

What is the recognised abnormailty on MRI that is indicative of CJD?

Answer 3

Increased signal in right parietal lobe

Question 4

What does ‘prion’ stand for?

Answer 4

PRotein-only InfectiOus ageNt.

Question 5

What is the general pathophysiology of prion diseases?

Answer 5

Rapid neurodegeneration via spongiform vacuolation

Question 6

Upon which chromosome is prion encoded?

Answer 6

C20

Question 7

Describe the structure and function of healthy prion

Answer 7

Alpha helical structure - involved in copper binding

Question 8

What is the structure of pathological prion?

Answer 8

Beta pleated sheet

Question 9

What is the name given to sporadic prion disease?

Answer 9

Creutzfeld Jacob Disease

Question 10

What are the 2 types of acquired prion disease currently known about?

Answer 10

1. Variant/ iatrogenic CJD (included mad cow BSE)

2. Kuru (Papau New Guinea)

Question 11

Recall 3 genetic/familial causes of prion disease

Answer 11

1. PRNP mutations
2. Gertsmann-Strausser-Sheinker syndrome
3. Familial fatal insomnia

Question 12

How does CJD present?

Answer 12

RAPID DEMENTIA with:

• myoclonus
• cortical blindness
• akinetic mutism
• LMN signs

Question 13

What is the mean age of onset of CJD?

Answer 13

65

Question 14

How quickly does CJD cause death?

Answer 14

Within 6/12

Question 15

What is the mean age of presentation of variant CJD/ BSE?

Answer 15

26

Question 16

What is the mean survival time in variant CJD?

Answer 16

14 months

Question 17

Recall the typical presentation of variant CJD/ BSE

Answer 17

Dysphonia (hoarseness of voice)
Hallucinations
Anxiety
Paranoia
(Psychological symptoms mostly)

Question 18

What would an MRI show in variant CJD/ BSE?

Answer 18

Positive pulvinar sign (hypersensitivities including the pulvinar thalamic nuclei)

Question 19

What test is 100% sensitive and specific for variant CJD/ BSE, but useless in sporadic CJD?

Answer 19

Tonsilar biopsy

Question 20

What is the inheritance pattern of prion proteins?

Answer 20

All autosomal dominant

Question 21

What are the symptoms of Gertsmann-Strausser-Scheinher syndrome?

Answer 21

Progressive ataxia