Nervous 4 (brain 2)

Question 1

What are prion diseases also called?

Answer 1

Transmissible spongiform encephalopathies (TSE)

Question 2

What are prions caused by?

Answer 2

Infectious proteins

Question 3

True or False: Prions have DNA

Answer 3

False! They do not have any DNA or a genome

Question 4

What is the normal version of the prion protein called?

Answer 4

PrPc

Question 5

Where is PrPc found?

Answer 5

In most living tissues

Question 6

What is the abnormal version of the prion protein called?

Answer 6

PrPSc

Question 7

What do PrPSc’s cause?

Answer 7

Neurological disease

Question 8

True or False: PrPSc is slightly different in each species and doesn’t easily transmit between different species

Answer 8

True

Question 9

What are two ways of getting PrPSc?

Answer 9

1. Acquired (CWD, BSE, scrapies)
2. Spontaneous mutation (normal proteins mutate into misfolded ones)

Question 10

How is CWD transmitted?

Answer 10

Horizontal transmission through saliva, blood, urine

Question 11

How is BSE transmitted?

Answer 11

Ingestion (cattle fed CNS tissue to other cattle)

Question 12

How is scrapies transmitted?

Answer 12

Ingestion and possibly vertical transmission

Question 13

True or False: The body makes an immune response against prions

Answer 13

False. The body does not recognize the protein as foreign, therefore no immune response.

Question 14

True or False: Prion disease are eventually fatal

Answer 14

True

Question 15

What do you see histologically with prion diseases (three)?

Answer 15

• No inflammation
• Cytoplasmic vacuolation of neurons and spongy change throughout the gray matter
• Vacuolation of the neurons and neuropil

Question 16

What species commonly get chronic wasting disease?

Answer 16

Deer

Question 17

What are the four main nutritional causes of polioencephalomalacia?

Answer 17

1. Thiamine (B1) deficiency
2. Sulfur toxicity
3. Lead toxicity
4. Salt toxicity

Question 18

What does polioencephalomalacia cause in cattle?

Answer 18

Acidosis

Question 19

Where is thiamine produced in adult ruminants?

Answer 19

In their rumen (by bacteria)

Question 20

What part of the brain does polioencephalomalacia target?

Answer 20

It targets deep gray matter of the cerebral cortex (sulci)

Question 21

True or False: Gross and histologic lesions are different between herbivores and carnivores

Answer 21

True

Question 22

What do you see grossly in herbivores with polioencephalomalacia?

Answer 22

• Bilaterally symmetric atrophy of the gyri with loss of gray matter and hydrocephalus ex vacuo
• Yellow discolouration (4 days)
• Can see autofluorescence at this point

Question 23

What is this likely a picture of?

Answer 23

Polioencephalomalacia

Question 24

What do you see histologically in herbivores with polioencephalomalacia?

Answer 24

Laminar cortical necrosis

Question 25

What do you see grossly in carnivores with polioencephalomalacia?

Answer 25

Bilaterally symmetric atrophy in caudal colliculi (grey matter)

Question 26

What is polioencephalomalacia also called?

Answer 26

Chastek paralysis

Question 27

How do pigs get salt toxicity (two)?

Answer 27

1. Direct (over consumption of salt - high salt concentration in water during periods of drought) 2. Indirect (water deprivation followed by sudden unlimited access to water)

Question 28

Salt toxicity is most common in which two species?

Answer 28

Pigs and poultry

Question 29

What condition do we see with salt toxicity that leads to polioencephalomalacia?

Answer 29

Edema

Question 30

What do you see histologically in pigs with polioencephalomalacia?

Answer 30

Distinct eosinophilic infiltrations in meninges

Question 31

How can horses get leukoencephalomalacia?

Answer 31

Ingestion of moldy corn (fungus in corn)

Question 32

What fungus causes equine leukoencephalomalacia?

Answer 32

Fusarium moniliforme

Question 33

Fusarium moniliforme forms which toxin?

Answer 33

Fumonisin B1

Question 34

What do you see grossly with equine leukoencephalomalacia?

Answer 34

Bilateral, but NOT symmetric malacia and liquefaction of the subcortical white matter (remember, leuko means white)

Question 35

How can horses get nigropallidal encephalomalacia?

Answer 35

If they graze on Centaurea spp. plants (yellow star thistle and russian knapweed)

Question 36

What are the clinical signs of nigropallidal encephalomalacia?

Answer 36

A persistent chewing movement (no food is in their mouth)

Question 37

What part of the brain does nigropallidal encephalomalacia affect?

Answer 37

The globus pallidus and substantia negra of the brain

Question 38

What do you see grossly with nigropallidal encephalomalacia?

Answer 38

Bilaterally symmetric, well-demarcated areas of yellow discolouration and malacia

Question 39

What causes domoic acid toxicity?

Answer 39

Domoic acid (a toxin produced by algae)

Question 40

Which species are affected by domoic acid toxicity?

Answer 40

Birds and marine mammals

Question 41

What do you see grossly with domoic acid toxicity?

Answer 41

Hippocampal atrophy

Question 42

What is the main clinical sign seen with domoic acid toxicity?

Answer 42

Seizures

Question 43

What are the three idiopathic encephalitides?

Answer 43

1. Granulomatous Meningoencephalitis (GME) 2. Necrotizing Meningoencephalitis (pug dog encephalitis) 3. Necrotizing Leukoencephalitis (NLE)

Question 44

Which dog breeds are mostly commonly affected by each of the three idiopathic encephalitides?

Answer 44

1. Granulomatous Meningoencephalitis - small breed dogs 2. Necrotizing Meningoencephalitis - small breed dogs 3. Necrotizing Leukoencephalitis - yorkies

Question 45

Which parts of the brain are affected by each of the three idiopathic encephalitides?

Answer 45

1. Granulomatous Meningoencephalitis - white matter 2. Necrotizing Meningoencephalitis - grey matter 3. Necrotizing Leukoencephalitis - white matter

Question 46

Which dog breeds are CNS tumors more common in?

Answer 46

Golden retrievers and brachycephalic breeds

Question 47

Which brain tumor cannot also occur in the spinal cord?

Answer 47

Choriod plexus tumor

Question 48

What is the most common tumor of the CNS?

Answer 48

Meningioma

Question 49

Meningiomas are most common in which species?

Answer 49

Cats

Question 50

What clinical signs do we see with ependymoma tumors?

Answer 50

Hydrocephaly

Question 51

Which dog breeds are predisposed to ependymoma?

Answer 51

Brachycephalic breeds

Question 52

Where do ependymomas most frequently occur in the brain?

Answer 52

The lateral ventricle

Question 53

Where do choroid plexus tumors most frequently occur in the brain?

Answer 53

The 4th ventricle

Question 54

What do you see grossly with choroid plexus tumors?

Answer 54

Granular to papillary growth

Question 55

What are the four types of gliomas?

Answer 55

1. Oligodendroglioma 2. Astrocytoma 3. Gliomatosis cerebri 4. Mixed (multiple of those cell types involved)

Question 56

Which dog breeds are predisposed to gliomas?

Answer 56

Brachycephalic breeds

Question 57

Are gliomas usually benign or malignant?

Answer 57

All are considered malignant

Question 58

What is an important differential for the gross appearance of cryptococcosis?

Answer 58

Gliomas (gross appearance is very similar)

Question 59

What is a cholesteatoma also called?

Answer 59

A cholesterol granuloma

Question 60

What species is commonly affected with cholesteatomas?

Answer 60

Older horses

Question 61

What do you see grossly with cholesteatomas?

Answer 61

Yellow brown firm nodular mass within the ventricles that can be mineralized

Question 62

What clinical signs do you see with cholesteatomas?

Answer 62

None really, it is predominantly asymptomatic