Pathology: infectious and non-infectious diseases of the neural system Flashcards

1
Q

Septic bacterial emboli are usually seen in young or old animals?

A

Young

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where in the brain do septic bacterial emboli typically become lodged?

A

In the cerebrum, at the grey/white matter junction
Causing thrombosis, malacia and abscessation
Histologically will see astrocytic encapsulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

A cow with a septic bacterial embolus is most commonly due to what bacteria?

A

T. pyogenes
Histophilus somnus
Staph aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A lamb with a septic bacterial embolus is most commonly due to what bacteria?

A

Staph aureus due to tick pyemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A horse with a septic bacterial embolus is most commonly due to what bacteria?

A

Strep equi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A dog with a septic bacterial embolus is most commonly due to what bacteria?

A

Staph aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What causes Thromboembolic Mengingoencephalitis (TME) in cattle?

A
  • Histophilus somni (a gram neg coccobacillus)

Causing acute vasculitis which primarily affects the CNS +/- lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What bacteria are most commonly associated with abscesses in the brain?

A

T. pyogenes
Strep spp
Staph spp
Pseudomonas aeruginosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 2 routes of infection to an abscess in the brain or spinal cord?

A
  • Hematogenous spread
  • Direct extension from a penetrating trauma, otogenic or frontal sinus
    e. g. migrating grass seed, tail docking in pigs or bulls, or tail biting
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

An abscess of the pituitary fossa in cattle is usually caused by?

A

Hematogenous spread of bacteria either from the caudal nasal cavity or frontal sinuses
e.g. nose rings in bulls, or dehorning older cattle

note: patient usually presents with a jaw drop or exopthalmus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

At what age is neonatal septicemia most common and why?

A

Within the first 2 weeks of life

Usually colostrum quantity or quality is lacking, or intrusion through the umbilicus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the most commonly found bacteria in neonatal septicemia?
(Calves, foals, small ruminants and swine)

A

Calves: E.coli, Salmonella, and Pasteurella spp
Foals: Salmonella spp and Actinobacillus equuli
Small ruminaints: Staph. pyogenes
Swine: Hemophilus parasuis

note: these bacteria will release endotoxins and cell wall components, leading to a cytokine secretion, adhesion of neutrophils to the endothelium and subsequent damage and vasculitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the most common bacterial pathogen associated with swine meningitis?

A

Streptococcus suis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the common lesions found in Streptococcal sepsis in piglets?

A

Lesions are mainly seen in weaned piglets and are associated with lymphadenopathy, meningitis, arthritis, and endocarditis.
Lesions may include fibrinopurulent exudates in the brain, swollen joints, fibrinous serositis, and cardiac valvular vegetation.
Splenomegaly and petechial hemorrhages indicating septicemia are common.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What causes Listeriosis in sheep?

A

Listeria monocytogenes (gram positive and facultative intracellular bacterium)

recall: this is a zoonotic disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the lesions associated with Listeriosis in sheep?

A

microabscesses in the brainstem due to retrograde movement up the trigeminal nerve
meningoencephalitis

note: can also cause abortion, septicemia and conjunctivitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A dog with nonsuppurative meningoencephalitis in the ventral brainstem and periventricular tissue is indicative of what disease?

A

Ehrlichiosis

agent: Ehrlichia canis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A dog with disseminated suppurative vasculitis is indicative of what disease?

A

Rocky mountain spotted fever

agent: Rickettsia rickettsii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

A dog/ fox with cerebellar meningitis is indicative of what disease?

A

Salmon poisoning

agent: Neorickettsia helminthoeca

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

A bovine with polyserositis and disseminated mononuclear-suppurative inflammation with vasculitis is indicative of what disease?

A

Sporadic bovine encephalitis

agent: Chlamydophila pecorum

21
Q

A horse with suppurative granulomatous meningoradiculitis is indicative of what disease?

A

Borrelia burgdorferi (lyme)

22
Q

What is an important mycotic disease that can cause neurological lesions in cattle?

A

Aspergillosis

note: often get abortion too and can see mycotic lesions in the aborted fetus brain

23
Q

What is an important mycotic disease that can cause neurological lesions in dogs and cats?

A

Cryptococcus neoformans and C.gattii

24
Q

What is an important mycotic disease that can cause neurological lesions in rabbits? and even dogs

A

Encephalitozoon cuniculi

25
What are the routes of invasion for viral infections that affect the brain?
- Hematogenous via BBB - Replications in vascular endothelium: canine adenovirus-1, ovine herpesvirus-2, equine herpesvirus-1 and Feline coronavirus - Neural: rabies, borna disease virus and herpesvirus
26
Neuro Viral infections can be divided into sub-categories depending on the histopathology seen, what are the neurotropic viruses (ones that damage the neurons)?
Rabies: all species Pseudo-rabies (suid herpes virus 1): pigs, cats and dogs Bovine herpesvirus-1 and -5: cattle Teschen/ Talfan Disease: post-weaning pigs Arthropod-transmitted viruses: Louping-ill (sheep, cattle, horses, dogs and human), West Nile virus (humans, horses, birds, cattle, sheep and small animals), Western & Eastern & Venezuelan equine encephalitis (horses and birds)
27
What viral infections cause granulomatous inflammation?
Caprine Arthritis Encephalitis virus: goats Equine Infectious Anemia: horses Feline Infectious Peritonitis: cats
28
What viral infections cause vasculitis?
Classical Swine Fever: swine Equine Herpesvirus-1: horses Malignant Catarrhal Fever (ovine and caprine herpes virus-2): cattle, sheep and goats Canine adenovirus: canids
29
What viral infections cause leukoencephalitis (inflammation of the white matter)?
Canine distemper: dogs Maedi-visna: sheep FIV/ FeLv: cats
30
What is the most common macroscopic change to the neural tissue in a viral infection?
Most common: NO CHANGE! sometimes haemorrhage and edema but not often note: so an animal with neurological issues with no macroscopic changes to the neural tissue is suggestive of a viral infection
31
What is the most common lesion found in the neural tissue during a protozoal parasitic infection?
Non-suppurative inflammation +/- abundant eosinophils
32
What is the definitive and intermediate host of Toxoplasmosis?
Definitive: cat Intermediate: sheep, rarely dogs, humans
33
What does Toxoplasmosis cause in sheep?
abortion + multifocal encephalitis in the fetus (lamb)
34
What is the definitive and intermediate host of Neosporum caninum?
Definitive: Dogs Intermediate: Cattle
35
What does Neosporosis cause in dogs and cattle?
Dogs: Myositis/ meningoencephalomyelitis + hindlimb paralysis Cattle: abortion at 5-6 months gestation with multifocal encephalitis in the fetus
36
What is the definitive and intermediate host to Sarcocystis neurona?
Definitive: possum Intermediate: horse (rarely dogs)
37
What kind of lesions are found in the neural tissue of the horse infected with Sarcocystis neurona?
Lesions in the spinal cord- necrotizing inflammation of the grey and white matter, perivascular mononuclear cuffs and infiltration of the parenchyma with neutrophils, eosinopphils and sometimes giant cells
38
What is the most common lesion found in the neural tissue during a helminth parasitic infection?
Suppurative with necrosis, haemorrhage with variable numbers of eosinophils, + granulomatous in chronic lesions
39
What is a common tape worm infection in sheep that can cause neurological signs?
Coenuris cerebralis ('Gid'), which is the encysted larvae of Taenia multiceps Dog excretes in the feces, sheep ingests it and it will migrate to the CNS
40
What is the difference between acute and chronic forms of Gid in Sheep? (Coenuris cerebralis)
Acute: occurs 3-4 weeks after ingestion, malacia is caused by the migratory tracts of many migrating larvae Chronic: occurs 6 months after ingestion, larve with encyst themselves in the cerebrum causing compression, edema, hydrocephalus and bone softening
41
What is the most common lesion found in the neural tissue during a non-infectious and/or immune-mediated inflammatory disorder?
Non-suppurative with various degrees of granulomatous inflammation Can affect the meninges, blood vessels, brain, spinal cord or peripheral nerves
42
What is Granulomatous meningoencephalomyelitis (GME) in dogs?
GME is an acute, progressive inflammatory disease of the central nervous system (CNS) of dogs. GME is a common differential for dogs that are affected by focal or diffuse neurological diseases
43
What age and breed is Granulomatous meningoencephalomyelitis (GME) most commonly seen in?
- Young to middle aged dogs | - Small breeds: terrier and toy breeds
44
What are the clinical signs associated with Granulomatous meningoencephalomyelitis (GME) in dogs?
- Depends on the location of the inflammation as it can occur anywhere in the neural system Spinal lesions: ataxia, paresis or paralysis Brainstem: vestibular dysfunction Cerebrum: changes in behaviour, forced movement and circling, depression and convulsions
45
What is Necrotizing meningoencephalitis (NME) in dogs?
Necrotizing meningoencephalitis (NME) is an idiopathic, breed specific, unique inflammation disorder of brain in small breed dogs diagnosed more frequently in young to adult animals, from six months to seven years of age
46
What lesions are commonly associated with Necrotizing meningoencephalitis (NME) in dogs? What lesions are commonly associated with Necrotizing Encephalitis (NE) in dogs?
NME: - Lesions in Cerebral cortex - Mainly grey matter, asymmetrical multifocal bilateral cerebal necrosis - Commonly affected: Pugs, Maltese, ShihTzu NE: - Lesions in midbrain, brainstem and cerebellum - Necrotizing lesions confined to white matter - Commonly affected: Yorkies, french bulldogs and Pomeranian
47
What are the 3 neurological immune-mediated inflammatory lesions in dogs?
1) Steroid responsive meningitis-arteritis: german shepherds and boxers 2) Idiopathic eosinophilic meningoencephalitis: golden retrievers and rottweilers 3) Greyhound meningoencephalitis: young greyhounds in ireland
48
What is Cauda Equina Neuritis?
A chronic, progressive, rare and sporadic disease in horses - Etiology unknown: possibly autoimmune or post-infectious following EHV-1 or allergy - Clinical signs include: tail paralysis, urinary incontinence, fecal retention, weakness, atrophy of the coccygeal muscles and atrophy of the hindlimb muscles - Histologically: Lesions consisted of nonsuppurative inflammation of the nerve trunks and proliferation of the perineurium of the cauda equina with marked swelling