Neuro 3

Question 1

what does the term lissencephaly mean?

Answer 1

absence of normal gyri and sulci of the cerebrum, aka it’s a smooth brain

Question 2

what are the names for a small brain cavity and a large brain cavity. what is a general cuase for these?

Answer 2

small=porencephaly
large=hydranencephaly

viral damage (like bluetongue, BVDV, etc)

Question 3

what two virus types can cause cerebellar hypoplasia?

Answer 3

parvoviruses like canine parvo and feline panluekopenia
pestiviruses like BVDV and classical swine fever

both types target rapidly dividing cells (so it hits the cerebellum)

Question 4

the most common CNS congenital anomaly is

Answer 4

hydrocephalus

Question 5

what is hydrocephalus?

Answer 5

abnormal accumulation of CSF within the cranium

Question 6

what is the cause of congenital hydrocephalus? which animals are predisposed to this?

Answer 6

secondary to in utero viral infection
- brachy breeds like chihuahua, bulldog, pug, yorkie, toy poodle, etc

Question 7

what are the three types of hydrocephalus?

Answer 7

• congenital
• acquired
• hydrocephalus ex vacuo

Question 8

what causes acquired hydrocephalus?

Answer 8

• some sort of obstruction (inflammatory blockage, infection, compression from a mass or abscess, etc)

Question 9

what is hydrocephalus ex vacuo and what causes it

Answer 9

-aka compensatory hydroephalus, where the CSF replaces lost neural tissue
not related to CSF obstruction, but is actually an aging change or can also happen after radiation exposure

Question 10

describe where fluid accumulation would be in each scenario regarding hydrocephalus if the bloackage were located:
- interventricular foramen between lateral and third ventricle
- blockage of mesencephalic aqueduct
- blockage of resorption of CSF

Answer 10

• unilateral dilation of affected lateral ventricle
• bilateral dilation of lateral ventricles, 3rd ventricle, and cranial part of mesencephalic aqueduct
• everything dilated!

Question 11

what are some gross findings of hydrocephalus?

Answer 11

• if congenital, an enlarged domed skull with prominent fontanelles
• atrophy and loss of interventricular septum pellucidum

Question 12

which breed of dog can have hydrocephalus but show no clinical signs?

Answer 12

toy breeds

Question 13

what is occipital dysplasia?

Answer 13

common incidental finding in toy breeds where there is an underdeveloped occipital bone of the skul, resulting in a keyhole shaped foramen magnum. it does not cause clinical signs

Question 14

what is this

Answer 14

occiptal dysplasia

Question 15

listeriosis is caused by _________, and has 3 disease presentations which are:

Answer 15

listeria monocytogenes, gram +, small ruminants, zoonotic
- meningoencephalitis (adult animals)
- abortion/stillbirth (young animals)
- septicemia (young animals)

Question 16

what is the pathogenesis of listeriosis in regards to meningoencephalitis?

Answer 16

• consumption of improerly prepared silage that contains high numbers of bacteria, trauma to the oral mucosa allows bacterial invasion, migration to trigeminal ganglia and then to the brainstem via retrograde axonal transport, leading to inflammatory damage in the brain

Question 17

what are some clinical signs of listeriosis and histo lesions?

Answer 17

C/S: circling, twisted neck, dullness, padding
histo: microabscesses w neutrophils

Question 18

histophilus comni, gram neg, causes what brain disease? in what animal is this most common?

Answer 18

thrombotic meningoencephalitis
feedlot cattle

Question 19

what is the pathogenesis of thombotic meningoencephalitis?

Answer 19

uncertain, but we know it gains entry via resp tract and gains access to blood causing a septicemia. it damages the endothelial cells leading to thrombosis

Question 20

what are some histo lesions for thrombotic meningoencephalitis

Answer 20

vasculitis, thombosis, and infarction

Question 21

what causes pituitary abscess

Answer 21

bacteria, usually opportunistic
pathogenesis not fully understood, possibly extension from sinus or ear infection, or maybe due to the fact that there is delicate blood supply in that area

Question 22

WOT

Answer 22

pituitary abscess (probably extension from sinuses, you can see pus there), suppurative sinusitis

Question 23

Enterotoxiemia of sheep and goats is caused by ________. what is the pathogenesis? what is the lay term for this disease?

Answer 23

clostridium perfringens type D
- sudden change in the intestinal environent (like large amounts of grain), causes proliferation of the bacteria and production of the epsilon toxin, which damages endothelial cells and spreads via the blood

over eating disease

Question 24

what is another name for enterotoxemia of sheep and goats?

Answer 24

focal symmetric encephalomalacia

Question 25

if this is from a sheep that just ate a ton of grain and then suddenly died, what is this disease pobably?

Answer 25

focal symmetric encephalomalacia/entertoxemia of sheep and goats you can see the symmetric hemorrhages in the brain

Question 26

edema disease in pigs is caused by

Answer 26

E coli, shiga toxin producing, cuases vascular damage

Question 27

who does edema disease usually target, and what lesions can you see on histo?

Answer 27

- the best of the herd, healthy feeder pigs - vascular necrosis and bilaterally symmetric areas of malacia in the caudal medulla

Question 28

a vareity of fungi can cause infection of the CNS, but usually sporadic and often secondary to

Answer 28

immunosupression

Question 29

cats can get a fungal disease of the brain where there are cystic gelatinous lesions in the brain. what is this called and what causes it?

Answer 29

cryptococcosis caused by cryptococcus neoformans

Question 30

this is a cat brain, what likely is this? what would be some histo findings of this case? What are you thinking predisposed this cat to getting this disease?

Answer 30

cryptococcosis caused by cryptococcus neoformans (or gatti) you can see the cystic gelatinous lesions in the brain histo: mild inflammation, can see the yeast sometimes (clear non staining capsule and narrow based budding) I would go looking if this cat had FIV or FeLV since immunosupression can cause this

Question 31

who is the definitive host for: - toxoplasma gondi - neospora caninum

Answer 31

toxoplasma: cats neospora caninum: dogs

Question 32

ruminants can be infected with toxoplasma gondi and neospora caninum. what does it cause?

Answer 32

non suppurative encephalomyelitis and polyraidculoneuritis (inflammation of nerve roots)

Question 33

what causes nervous coccidosis of calves?

Answer 33

a unusual nervous presentation associated with intestinal coccidia infection (eimeria), common in calves 1 month to 1 year old, the calves hsow nerulogical signs but we have no idea why this happens

Question 34

what is a nematode worm of racoons that is zoonotic? where do the larvae migrate to? what would be a histo lesion? who gets these besides racoons?

Answer 34

baylisascaris procynosis larvae migrate to the brain and the eye histo: eosinophilic encephalitis dogs and birds get this from consumption of eggs from racoon feces and these eggs are very resistant!!!

Question 35

canine distemper virus infects what tissues/cells, and targets what 3 systems?

Answer 35

- lymphoid and epithelial tissues/ macrophages - lungs, GI tract, and CNS

Question 36

what is the pathogenesis of canine distemper virus?

Answer 36

transmission via aerosol, initial replication in the lymph nodes causing immunosupression and secondary infections, leukocyte trafficking allows migration to the CNS and other epithelium

Question 37

how do dogs with distemper virus often present?

Answer 37

rhinitis, conjunctivitis, and pneumonia

Question 38

what are some clinical signs of canine distemper virus?

Answer 38

usually in puppies, fever, conjunctivitis, nasal discharge, vomiting, diarrhea, hyperkeratosis of the footpads and nose, enamel hypoplasia

Question 39

what are some histo lesions of canine distemper virus?

Answer 39

demyelination (seen as white matter vacuolation) intracytoplasmic AND intranuclear viral inclusion bodies

Question 40

what causes equine encephalomyelitis?

Answer 40

arboviruses like West Nile virus transmitted via mosquitos or birds, causing a polioencephalomyelitis (grey matter)

Question 41

what are the three key organs to west nile virus in birds?

Answer 41

brain, kidney, heart

Question 42

give two examples of lentiviruses that are of importance and what 4 body systems they target

Answer 42

- caprine arthritis and encephalitis virus (CAEV) in goats - maedni virus (MV) in sheep, causes ovine progressive pleuropneumonia 4 systems: CNS (non suppurative leukoencephalomyelitis), lung, joints (hygroma), mammary gland

Question 43

how are small ruminant lentiviruses transmitted and what cells do they infect? how do they get to the CNS? what age is commonly affected?

Answer 43

transmission via milk/colostrum infect monocytes/macrophages get into CNS via leukocyte trafficking usually causing disease in young goat kids, they will have neurologic disease and may have penumonia as well this disease targets the white matter (demyelination)