neuropathology 2 Flashcards
CNS disease categories
- Malformations
- Encephalitis / Inflammatory
- Encephalopathy / noninflammatory
- Neoplastic
Malformation of the CNS
- general reasons for this
- Spontaneous
- Hereditary
- Toxic
- Post infectious
Malformations of CNS - common ones
- Hydrocephalus
- Hydranencephaly
- Cerebellar hypoplasia
Hydrocephalus - what is this? types?
- Water brain > Bone forms to brain
- Ventricles dilated
- Internal - common
- External - rare
Hydranencephaly - what is this?
- what is the mild form?
- water, but no brain
- cerebrum doesnt develop
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Mild hydranencephaly = porencephaly
> holes in the brain, because some parts formed, but others did not
Cerebellar hypoplasia - what animal and disease is this related to most?
Feline panleukopenia virus
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> can also see this in calves (BVDV)
Neurotropic viruses that cause malformations
- Family Flaviviridae; Genus Pestivirus;
> Pestivirus bovis, P. tauri (BVDV1 and BVDV2),
> Pestivirus suis (Classical Swine Fever V),
> Pestivirus ovis (Border Disease virus) - Family Parvoviridae; Genus Protoparvovirus; Species Protoparvovirus carnivoran1:
Feline panleukopenia virus - Family Reoviridae; Genus Orbivirus; Bluetongue virus
- Family Peribunyaviridae; Genus Orthobunyavirus;
> Orthobunyavirus akabaneense (Akabane virus),
> Orthobunyavirus cacheense (Cache Valley virus),
> Orthobunyavirus schmallenbergense (Schmallenburg virus)
Encephalitis \ Inflammation
> infectious causes / types
- Neutrophilic (Bacteria)
- Lymphocytic (viral)
- Eosinophilic (Parasitic)
- Granulomatous
- Necrotic/ Myelinopathy/ Malacic
Cells of the Central Nervous System
- Neuron > Nerve cell body, axon and dendrites
- Microglia and macrophages > Myelin macrophages
- ‘Macroglia’
> Astrocytes (multifunctional)
> Oligodendrocytes (myelin production)
> Neurolemmocytes (Schwann cells) too - Stem cells – neuroblasts, aldynoglia
Route of entry of pathogens to CNS
- Exposure – primary replication – blood – tropism for CNS
- Veins (cornual – ophthalmic – cavernous sinus)
- Direct penetration > dehorning
- Along nerves > Herpesviridae, Lyssavirus, Listeria
- Through CSF > Spinal abscess
Central Nervous System: Inflammation
1: Neutrophilic inflammation - bacterial
- mostly what? pathogens?
- lesions?
- exceptions?
- Mostly Meningitis
> Ruminants
=> E. coli
=> Streptococci
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> Brain
> Trueperella pyogenes
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– exceptions: - pituitary abscess
- Listeria monocytogenes
> Cattle, sheep and goats
> Mouth
> Trigeminal nerve (V) and ganglia
> Microabscesses in pons and medulla - Histophilus somni
> Gram -, necrosis to small vessels and
neutrophils, thrombosis, microinfacts =
malacia
- Lymphocytic (viral) encephalitis
- lesions
- ‘nonsuppurative’ encephalitis
- Perivascular cuffs
- Gliosis > Focal, Diffuse
- Neuronal lesions > Necrosis, Satellitosis, Neuronophagia
- Viral diseases of CNS, for all species:
All species:
- arboviruses
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- Family Rhabdoviridae
> Genus Lyssavirus – Rabies lyssavirus
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- Family Herpesviridae
> Genus Varicellovirus - BoHV, CaHV, FeHV
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- Family Paramyxoviridae
> Genus Morbillivirus – Canine morbillivirus (Distemper)
> Genus Henipavirus – Nipah henipavirus, Hendra henipavirus
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- Family Astroviridae
> Genus Mamastrovirus - BoAstV, PoAstV, OvAstV
viral diseases of CNS in horses
- Family Togaviridae; Genus Alphavirus
> Eastern equine encephalitis virus,
> Western equine encephalitis virus
> Venezuelan equine encephalitis virus
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Family Flaviviridae; Genus Flavivirus - West Nile Virus
Viral encephalitis - RABIES - signs in horses, cattle, dogs
- Lyssavirus rabies: Rabies virus
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Horses - ‘lameness’, ataxia
Cattle - paralysis
Dogs - aberrant
