Path TarC: CNS and Neuro

Question 1

What viruses can cause cerebellar hypoplasia?

Answer 1

COWS - BVDV before 180d pregnancy (after this calf mounts immune response)
SHEEP - BTV (blue tongue virus) BDV (border dz virus) and Cache Valley virus in north America

Question 2

What lesions does EHV1 cause? Clinical signs?

Answer 2

• random foci of haemorrhage, multiple segments of cord, predominantly grey matter
  > ataxia, paralysis, recumbency

Question 3

Path of EHV1?

Answer 3

• vasculitis consequences most noticeable in small aa./arterioles of SC
• multifocal tissue hypoxia and ischaemia
• neuronal axons respond in limited ways
• swell forming SPHEROIDS

Question 4

how can EHV1 be dx clinically?

Answer 4

• PCR detection of virus in blood sample/CSF

Question 5

Advice to owner if EHV1 suspected/dx?

Answer 5

• alert other woners on the yard

- don’t transport/shows etc.

Question 6

What pathogen causes FIP?

Answer 6

• FCoV mutated

- widespread in cats, usually only causes mild enteritis/subclinical disease until mutation occours

Question 7

Pathogenesis of FIP?

Answer 7

> virus -> immune mediated dz

• immune complexes (vius Ab complexes) trapped in small vessels -> vasculitis -> effusive WET form (=EHV1 pathogenesis)
• continuous cell mediated immune response against infected macrophages causig granuloma in infected organs (DRY form)

Question 8

Describe lesions found with supparaive bacterial meningitis

Answer 8

• pale yellow-cream exudate covering surface of brain within the meninges
• multifocal areas of haemorrhage

Question 9

What bacteria can cause meningitis in piglets? What else can this pathogen cause?

Answer 9

> strep suis (ZOONOTIC)

• no uncommon cause of acute and frequent fatal meningitis in suckling and weanling pigs
• can also cause polyserositis (peritonitis, polyarthritis, pleuritis)

Question 10

Clinical signs of rabies or rabies like virus (LYSSAVIRUS) in a cow?

Answer 10

• excessive salivation
• behavioural change
• muzzle tremors
• abnormal posture
• tenesmus
• opisthtonus
• seziures
• widespread paralysis and death

Question 11

How deos abies/lylssavirus reach the brain?

Answer 11

retrograde axonal transport - replicates in neurons and glial cells once it has reached the brain

Question 12

What histopathological findings are characteristic of lyssavirus infection?

Answer 12

NEGRI BODIES

- eosinophilic intracytolplasmic inclusion bodies

Question 13

How can rabies be confirmed in the lab?

Answer 13

• no of techniques, based on fresh impession smears of the brain
  > immunofluorescence and IHC most common
  > viral isolation and PCR