Neuropathology

Question 1

What is this?

Answer 1

–Chromatolysis after axonal damage or toxicity

= neuronal degeneration, reversible

Question 2

What is this?

Answer 2

–Hypereosinophilic, shrunken, dead neurons due to ischaemia, hypoglycaemia, vitamin deficiencies (thiamine) or intoxications (cyanide, lead, mercury)

= neuronal necrosis, irreversible

Question 3

What is this?

Answer 3

–Swollen neurons due to (lysosomal) storage diseases

Question 4

What is this?

What are the types and when are they seen?

Answer 4

–Viral inclusion bodies:

• Nuclear: Herpesvirus, Adenovirus, Bornavirus
• Cytoplasmic: Poxvirus, rabies
• Both intranuclear and intracytoplasmic: Paramyxovirus (Distemper)

Question 5

Wha is this? When is it seen?

Answer 5

–Cytoplasmic vacuolation on spongiform encephalopathies (BSE, scrapie, FSE

Question 6

What is this? When is it seen?

Answer 6

Demyelination e.g. distemper

Question 7

What is this? When is it seen?

Answer 7

Hypomyelination

in cases of in utero infection with BVDV or Border disease

Question 8

What is this?

Answer 8

•Vasogenic oedema

(Increased extracell. fluid)

Question 9

What is this?

Answer 9

•Cytotoxic oedema

(Increased intracell. fluid)

Question 10

What are the 5 disease categories?

Answer 10

• Congenital anomalies/malformations
• Trauma/vascular
• Inflammation/infection
• Degeneration
• Neoplasia

Question 11

In CNS what does manifestation of disease generally reflect?

Answer 11

Location injury

Question 12

What can be seen and what causes it?

Answer 12

Congenital hydrocephalus

Expansion of the ventricles due to obstruction and back up of CSF and/or loss of CNS tissue (pressure atrophy or necrosis or hypoplasia).

Question 13

What is this?

Answer 13

Lhasa apso with congenital lissencephaly resulting from disturbance of neuronal migration and proliferation during development

Question 14

What is this?

Answer 14

Cerebellar hypoplasia, BVDV

Question 15

What are these?

Answer 15

Cerebral infarct

Question 16

What causes cerebral infact?

Answer 16

Vaculitis

Thromosis

Embolism

Question 17

What is the result of cerebral infarction?

Answer 17

Sudden onset of clinical signs, liquifactive necrosis (malacia)

Question 18

What is this?

Answer 18

Acute cerebellar infarct, dog

Question 19

A) What is this?

B) What is the potential aetiology?

Answer 19

A) Myelomalacia

B) Fibrocartilaginous embolism

(FCEM)

Question 20

What is this?

Answer 20

Herniated intervertebral disk, spinal cord. The disk material (arrows) lies in the epidural space, touches the dura mater, and compresses the overlying spinal cord. An area of necrosis, possibly caused by infarction is present in the ventral area of the left lateral funiculus (arrowhead). The multiple small holes in all funiculi are the sites of lost nerves as the result of spinal cord compression, which caused Wallerian degeneration.

Question 21

Name a bacteria which enters haematogenously?

Answer 21

Streptococci

Question 22

Name 2 things which intraaxonal?

Answer 22

Viruses such as Rabies, bacteria like Listeria

Question 23

How can a direct extension cause neuropathology?

Answer 23

From sinusitis, otitis, abcesses

Question 24

Name a virus which route of entry is within a leucocyte

Answer 24

Canine distemper virus

Question 25

What causes this?

Answer 25

Suppurative meningoencephalitis Streptococcus suis. Pyogenic bacteria often derive from navel-ill in young animals

Question 26

What is this?

Answer 26

Haemophilus parasuis ## Footnote Haemophilus parasuis, Glasser’s disease (polyserositis, polyarthritis).

Question 27

What is this?

Answer 27

Caudal brainstem. Suppurative foci - numerous neutrophils and some macrophages infiltrate the neuroparenchyma (also called ‘microabscesses’). Gram positive bacteria, Listeria monocytogenes. It is a zoonotic disease. Listeriosis is primarily a winter-spring disease of feedlot or housed ruminants. The less acidic pH of spoiled silage enhances multiplication of L monocytogenes.

Question 28

What is this?

Answer 28

Viral infections often manifest as a non-suppurative (meningo-)encephal(omyel) itis

Question 29

What is this?

Answer 29

Aujeszky’s Disease High magnification images of lesions in the cerebral cortex, characterised by perivascular cuffing and intense focal gliosis and inflammatory infiltration within the neocortex. Some neutrophils are present in the infiltrate. | (pseudorabies, porcine herpes virus)

Question 30

What is this?

Answer 30

Prion disease (TSEs) ## Footnote Bovine Spongiform Encephalopathy - Caudal brainstem grey matter. Left panel - Low magnification view of spongiform change in the neuropil, the definitive lesion of the prion diseases. Right panel - striking multiple large vacuoles in the perikaryon of a large neuron.

Question 31

What is this?

Answer 31

Cerebral cortical necrosis (CCN) (= polioencephalomalacia = PEM) Acute cerebrocortical polioencephalomalacia, thiamine deficiency, brain, parietal lobe, level of thalamus, goat. Note the liquefactive necrosis with varying degrees of tissue separation (arrows) in the deep cortex.

Question 32

What is this?

Answer 32

CCN or polioencephalomalacia (PEM)

Question 33

What is this?

Answer 33

Symmetrical poliomyelomalacia Selenium toxicosis in pigs

Question 34

Name some primary neoplasias of the CNS

Answer 34

Meningioma Astrocytoma Oligodendroglioma Ependymoma/Choroid plexus tumour Neuroblastoma/Medulloblastoma (PNET)

Question 35

What is this?

Answer 35

Astrocytomas and Oligodendrogliomas: more common in dogs than cats, especially in brachycephalic dogs

Question 36

What is this?

Answer 36

Astrocytoma