Test 4: 2: neuropath Flashcards
1
Q
order of the ventricular system of the CNS
A
2
Q
gray matter in the CNS is organized
A
laminae or nuceli
found on the outside of the brain
inside of the spinal cord
made of neuronal cell bodies and dendrites
3
Q
white matter of the CNS is organized
A
into tracts
conduction of nerve impulse from grey matter(nuclei or laminae)
made of neuronal axons surrounded by myelin
on inside of brain, outside of spinal cord
4
Q
nissel substance in the neuron is made from
A
rough ER
where neurotransmitters are being processed into vesicles
golgi
5
Q
what makes up grey matter
A
neuronal cell bodies
dendrites
glial cells
6
Q
what makes up white matter
A
axons
axon terminals/synaptic end bulbs
used for conduction of impulse
7
Q
three type of CNS glial cells
A
astrocytes
microglia
oligodendrocytes
8
Q
astrocytes maintain —, regulate —, — synapses and can respond to injury
A
blood brain barrier
nutrients
insulate
astrocytosis/gliosis
9
Q
microglia are the resident — of the CNS, help regulate —
A
macrophage- phagocytosis and antigen presenting
neuron function
microgliosis/gliosis
10
Q
oligodendrocytes make —, one cell insulates —, can respond to myelin injury by —
A
myelin
one cell- multiple neurons
OPC regeneration
11
Q
schwann vs oligodendrocytes
A
many schwann one neuron
one oligo= many neurons
makes myelin
12
Q
— cells make CSF
A
chroid plexus cells
Epithelial-endothelial
border (Blood CSF Barrier)
13
Q
— cells line the ventricles and move CSF
A
ependymal cells
14
Q
pachymeniges are the —
A
dura mater
15
Q
leptomeninges are the —
A
arachnoid mater
subarachnoid space
pia mater
16
Q
3 components of the blood brain barrier
A
Specialized vascular endothelial cells
Tight junctions and unique basement membranes
Astrocyte foot processes
17
Q
some functions of the blood brain barrier
A
Protects the brain from pathogens and xenobiotics
Regulates diffusion of hormones and cytokines
Contributes to sustain the delicate CNS homeostasis
18
Q
2 components of the blood meningeal barrier
A
Specialized vascular endothelial cells
Tight junctions and basement membrane
19
Q
function of the blood meningeal barrier
A
Same properties as BBB but less restrictive and promote immune responses during injury/infection
20
Q
3 components of the blood CSF barrier
A
Choroid plexus epithelial cells with tight junctions
Vessels in choroidal stroma are fenestrated
Arachnoid membrane
21
Q
function of the blood CSF barrier
A
Regulates movement of agents from blood to CSF
22
Q
A
23
Q
upper vs lower motor neuron
A
upper do not leave CNS (come from the motor cortex or nuceli in the brain stem and will synapse will lower motor neuron in the spinal cord, activates skeletal muscle
24
Q
what caused this
A
thiamine deficiency in carnivore
neuronal necrosis
posterior colliculi neuronal cell bodies
25
what caused this
copper deficiency
oligodendroglia dysfunction
diffuse cerebral **white mater** loss
leukoencephalomalacia: necrosis of the white matter of the brain
26
another name for necrosis in brain
malacia
27
what type of neoplasm
meningioma
cause atrophy of the brain
28
encephalomalacia
encephalomalacia: necrosis of the brain
29
polioencephalomalacia
necrosis of the grey matter of the brain
30
leukoencephalomalacia:
necrosis of the white matter of the brain
31
myelomalacia
necrosis of the spinal cord
32
poliomyelomalacia
necrosis of the grey matter of the spinal cord
33
leukomyelomalacia
leukomyelomalacia: necrosis of the white matter of the spinal cord
34
thiamine deficiency in ruminants will do what to the brain
Polioencephalomalacia of ruminants: necrosis of the grey matter of the brain
laminar cortical necrosis
Clinical signs: facial twitching, grinding teeth, opisthotonos, convulsions, coma
Causes: thiamine deficiency, high sulfur diets, water deprivation
35
Polioencephalomalacia of ruminants-necrosis of the grey matter of the brain
* Laminar cortical necrosis
* Clinical signs: facial twitching, grinding teeth, opisthotonos, convulsions, coma
* Causes: thiamine deficiency, high sulfur diets, water deprivation
36
what can cause ventricular dilation (hydrocephalus)
Excessive formation of CSF
Obstruction of CSF flow within ventricular system or subarachnoid space
Lack of resorption
Focal or diffuse loss of parenchyma → ventricles expand and CSF fills the space
( hydrocephalus ex-vacuo)
37
hydrocephalus (ventricular dilation)
38
what causes this
cerebellar herniation with compression of brainstem breathing centers leading to death
hemorrhage or edema or tumor can cause this
39
what happens during neuronal degeneration
chromatolysis
peripheralization of nucelus
neuronal swelling
increased glial cells
40
what happen to neurons during acute neuronal necorsis
shrunken
angular
pink (hypereosion)
increased glial cells
41
what happens during degeneration of axons
swelling and spheroid formation
digestion chambers (phagocytosis of axon debris)
42
what disease
neuronal ceroid lipofuscinosis
Accumulation of lipofuscin (oxidation of fatty acids)
* Likely mitochondrial defect (not lysosomal defect)
## Footnote
storage disease
43
what disease in the brain that causes neuronal vacuolization
Transmissible spongiform encephalopathies
(mad cow= bovine spongiform encephalopathy)
Accumulation of misfolded prion proteins (PrP)
44
what causes this neuronal vacuolization
Hepatic encephalopathy
**Ammonia toxicity**: changes in transport of amino acids and electrolytes into neurons
disrupting function and causing cytoxic/intracellular edema
**Astrocytosis** (Type II, aka Alzheimer’s type II – arranged in pairs and small clusters)
45
What are some things that cause necrosis of neurons
ischemia, hypoglycemia, seizures, viral infection, or toxins
46
hypertrophy and hyperplasia of astrocytes is called
astrocytosis
47
astrocytes can respond to injury by laying down ---
astrocytic fibers
glial scars
(fibrosis like)
48
Neuronophagia
glial nodules
glial cells surround dying neuron
accumulation of mononuclear cells, oligodendrocytes,
microglia, and neutrophils or astrocytes, around or at the site of a neuronal cell body
49
what common infection causes secondary demyelination
canine distemper
50
why are primary demyelination rare
deadly
Leukodystrophies (genetic enzyme defects; rare)
51
what is happening
demyelination (white mater)
## Footnote
(luxol-fast blue stain)
Caused by damage to the oligodendrocytes (CNS) or Schwann cells (PNS)
Remyelination is very poor in the CNS, but usually successful in the PNS
52
what neural tube defect
spina bifida
53
what neural tube defect
meningeocele
54
Agyria (lissencephaly)
Complete lack of the normal number and thickness of
cerebral hemispheric gyri
55
similar to Chiari type I malformation in people
Caudal occipital malformation (COMS)
common in Small breed dogs (Cavalier King Charles Spaniels)
Congenital malformation of caudal occipital region of skull → overcrowding of caudal fossa →
compression of the brainstem and cerebellum at the level of the foramen magnum (arrowhead)
→ **Syringomyelia**: accumulation of fluid within the spinal cord (aka **syrinx**) (arrow)
56
Syringomyelia:
accumulation of fluid within the spinal cord (aka syrinx)
can be caused by Caudal occipital malformation (COMS)
57
what went wrong?
## Footnote
c
cerebellar hypoplasia
congenital defect
or
Viral: Feline panleukopenia virus, bovine viral diarrhea virus, border disease virus, and classical swine fever virus.
58
what virus can cause cerebellar hypoplasia
Feline panleukopenia virus, bovine viral diarrhea virus, border disease virus, and classical swine fever virus.
59
brain= what is this showing
cerebellar hypoplasia
loss of purkinje and granular cells
caused by genetic or viral ( feline panleukopenia virus, bovine viral diarrhea virus, border disease virus, and classical swine fever virus.
60
cerebellar abiotrophy is caused by ---
genetic or idiopathic
born normal then losses purkinje cells and granular cells
accelerated degeneration
61
cerebellar abiotrophy vs cerebellar hypoplasia
both are loss of purkinje and granular cells in the brain
hypoplasia: caused by virus- **born abnormal**
abiotrophy: unknown cause- **born normal** then accelerated degeneration
62
atherosclerosis in animals is related to ---
hypothyroidism and DM
Mini Schnauzers predisposed
63
Feline ischemic myelopathy and encephalopathy is associated with
Hypertension, Hypertrophic cardiomyopathy, Chronic renal failure
ventral spinal artery most common
64
Fibrocartilaginous embolism (FCE) is caused by
Intervertebral disc emboli (fibrocartilaginous emboli) → occlusion of small blood vessels → infarct → necrosis (**myelomalacia)** → Macrophages remove necrotic debris
history: dogs very active then acute onset of disuse of back legs
65
vascular anomalies
Hemangiomas, arteriovenous malformations
benign but can rupture and squish things around it
66
intervertebral discs
**Nucleus pulposus (NP)**: central
gelatinous proteoglycan-rich substance
**Annulus fibrosus (AF)**:
surrounding concentric fibrous lamellae comprised of collagen and elastin
67
hansen type I herniation
Extrusion of **nucleus pulposus** material into the
spinal canal, resulting in spinal cord compression
acute causes full paralysis
68
hansen type II herniation
Protrusion of the **annulus fibrosus** into the spinal
canal, resulting in spinal cord compression
69
patients with IVDD usually have hansen type ---. Will often present with impaired motor function or complete loss of voluntary movement in both hind limbs (---)
type 1
paraplegia
## Footnote
acute onset
small dogs (Dachshund, Lhasa Apso, Shih Tzu)
70
IVDD caused by hansen type --- leads to onset of symptoms that is slow and progressive
type II
paraparesis→ paraplegia
71
storage disease
Cellular catabolism: degradation of macromolecules
in vesicular compartments (i.e. ---) to smaller molecules to be reused or excreted (aka: ---)
lysosomes
autophagy
72
storage disease is caused by problem with enzymes caused by
genetic mutation resulting in dysfunctional enzyme
ingestion of substance that interferes with enzyme function (swainsonine- plant with alkaloid enzyme inhibitor)
73
Degenerative Myelopathy occurs in what type of dogs
german shepherd
corgi
74
Degenerative Myelopathy causes ---
Late onset (≥7 years), progressive Weakness and ataxia due to spinal cord lesions
Spheroids and demyelination in **dorsal funiculi**
* SOD1 mutation has been found in corgis (and other breeds)
75
corgis with SOD1 mutation get ---
degenerative myelopathy
76
neuroaxonal dystrophy
77
neuroaxonal dystrophy affects --- dogs and --- horses
Rottweilers, Papillons, Chihuahuas, Collie sheepdogs,
Jack Russell Terriers
Quarterhorse (and others: Morgans, Appaloosa,
Lusitano, Haflinger…)
78
what part of the CNS does neuroaxonal dystrophy attack
Brainstem (cuneate and gracilis nuclei),
Thoracic spinal cord nuclei
forms spheroids
leads to intermittent weakness of hind legs
79
encephalitis
inflammation of the brain
80
polioencephalitis:
inflammation of the grey matter of the brain
81
leukoencephalitis:
inflammation of the white matter of the brain
82
myelitis:
inflammation of the spinal cord
83
4 ways for infection to get into nervous system
blood
local extension
direct penetration
retrograde axonal flow (listeria, rabies, herpes)
84
rabies is caused by ---
Lyssavirus (Rhabdoviridae)
85
rabies cellular tropsim is for ---
neurons
uses retrograde axonal flow to travel to brain through nerves
86
how to test for rabies
Direct fluorescent antibody test (dFA, IF)
87
rabies histo will show perivascular ---, --- inclusion bodies in the neurons
cuffing
intracytoplasmic (negri bodies)
88
canine distemper virus is caused by
Morbillivirus (Paramyxoviridae)
89
how to transmit canine distemper
respiratory secretions
90
what cells do canine distemper attack
epithelium(conjunctiva), lymphoid (macrophages and lymphocytes)
91
clinical signs of canine distemper virus
**respiratory:** Conjunctivitis, rhinitis, and bronchopneumonia
**GI**:Diarrhea and vomiting
**CNS**: nervous, Seizures, cerebellar or vestibular ataxia
92
histo of canine distemper virus shows --- inclusion bodies in --- cells
Intracytoplasmic AND intranuclear
astrocytes, neurons, choroid plexus epithelium
93
what happens to the white matter with canine distemper virus
demyelination of the cerebellum, midbrain, brainstem, optic nerves, spinal cord
leukoencephalitis
94
canine distemper does what to gray matter
**Neuronal necrosis** with gliosis and perivascular **cuffing** of lymphocytes and macrophages
95
histo of arbovirus such as EEE
Pe rivascular cuffing by lymphocytes and plasma cells And **neutrophils!**
with glial nodules (neuronophagia)
96
caprine arthritis and encephalitis virus is spread by
direct contact
through milk leading to persistent infection
97
what cells does caprine arthritis and encephalitis virus attack
macrophages
98
clinical signs of caprine arthritis and encephalitis virus in young goats
Nervous system disease = hind limb lameness and ataxia with
paresis that progresses over several weeks to paralysis
* Usually fatal
99
clinical signs of caprine arthritis and encephalitis virus in adult goats
arthritis
pneumonia
encephalomyelitis
100
caprine arthritis and encephalitis virus histo shows
Perivascular **cuffing** by lymphocytes and macrophages with **malacia** particularly in the **white matter** of the subependymal cerebrum, brainstem, and beneath the pia in spinal cord
101
FIP is caused by ---
enteric coronavirus is mutated inside a cat to feline infectious peritonitis virus
102
how is FIP spread
fecal oral
most common in young cats
103
FIP attacks what cell types
intestinal epithelium and macrophages
104
clinical signs of FIP
varied (aggression, rage, hiding/withdrawal), convulsive disorders, nystagmus, head tilt or circling
**Pathological findings**: Hydrocephalus, granulomatous meningitis, choroid plexitis, ependymitis, and vasculitis (immune complex)
105
--- is a DNA virus that causes vasculitis leading to thrombosis in horses
Equine herpesviral myeloencephalopathy
Equine herpesvirus-1 and 4 (Alphaherpesvirinae)
106
what type of cells do equine herpes attack
epithelium, endothelium and neurons
lives forever in neurons- waiting
107
equine herpesviral myeloencephalopathy is caused by vasculitis with --- leading to secondary ischemia and axonal ---.
thrombosis, edema and hemorrhage
spheroids
108
most common cause of bacterial meningitis
E. coli, Streptococccus spp.
* Plus Pasteurella, Salmonella in young large animals
109
pachymeningitis
Inflammation of dura mater
pachymeninges is another name for dura mater
110
how does listeria cause encephalitis
large animal eats food containimated with Listeria monocytogenes
Break in oral mucosa → invasion of Listeria locally and into **trigeminal** nerves → travel **retrograde** up axon to the brainstem→ suppurative encephalitis with **microabscesses** in the **brainstem**
## Footnote
can cause abortion and mastitis
111
Infectious thrombotic meningoencephalitis (ITME) is caused by ---
Histophilus somni
Cattle
112
how does Histophilus somni in cattle cause Infectious thrombotic meningoencephalitis (ITME)
toxin from bacteria causes pneumonia that leads to vasculitis then thrombosis and hemorrhage
grossly causing multifocal random hemorrhage
113
cat brain
Cryptococcus neoformans (and C. gatii)
yeast
can infect dogs,cats and horses
causes suppurative to granulomatous meningoencephalitis with large areas of necrosis (“pseudocysts”) that contain numerous yeast
114
Cryptococcus neoformans (and C. gatii) will cause the formation of --- meningoencephalitis with areas of ---
suppurative to granulomatous
necrosis (“pseudocysts”) that contain numerous yeast
115
--- is an good example of local extension from the nose into the brain in cats
Cryptococcus neoformans (and C. gatii)
causes nose deformaty and then Suppurative to granulomatous meningoencephalitis with large areas of necrosis (“pseudocysts”) that contain numerous yeast
116
three protozoa that cause infections in the CNS
**Toxoplasma gondii**
* Can infect nearly any mammalian species
* Definitive host is cat
**Neospora caninum**
* Disease in dogs, cattle, deer
* Definitive host is dog
**Sarcocystis neurona**
* Equine Protozoal Myeloencephalitis (EPM)
* Definitive host is opossum, other wildlife
117
Equine Protozoal Myeloencephalitis (EPM)
is causes by
Sarcocystis neurona
a protozoa, definitive host opossum
118
protozoal infection of the brain will present as ---
organism moving through tissue will cause necrosis
Multifocal granulomatous, (eosinophilic), necrotizing encephalitis
can rarely see the organism surrounded by glial cells
119
EPM can look similar to
equine herpes virus
weakness and acute ataxia
EPM is caused by sarcocystic neurona and has no long lasting infection
120
three types of meningoencephalomyelitis of unknown origin (MUO)
**Granulomatous meningoencephalomyelitis (GME)**- any breed, caudal CNS- brainstem and spinal cord
**necrotizing meningoencephalomyelitis (NME)**- small dogs, cerebral
**necrotizing encephalitis (NE)**- small dogs, cerebral
121
Bromethalin toxicity attacks the ---
attacks electron transport chain
Uncouples oxidative phosphorylation in mitochondria
leads to edema
Decreased ATP synthesis and dysfunction of ATP-dependent Na/K pump → accumulation of Na (and water) in cells → cytotoxic cerebral edema → cerebral edema, including intramyelinic edema, myelin splitting, and axonal swelling (white matter vacuolation)
## Footnote
type of nonanticoagulant rodenticide
122
Bromethalin toxicity will cause --- in the brain
white matter edema
rodent killer that attacks electron transport chain
123
yellowstar thistle toxicity in horses will cause malacia in the --- and the ---
## Footnote
pastures containing Centaurea solstitialis (yellow star thistle) or C. repens (Russian knapweed)
124
--- deficiency will lead to malacia of the caudal colliculi or the rostal midbrain/caudal brainstem nuceli and cerebral cortex in carnivores
thiamine
in ruminants will attack the grey matter
125
deficiency in --- will cause this in lambs and kids
copper
swayback
Bilaterally symmetrical cavitation of the cerebral white matter
(congenital)
Wallerian degeneration in
dorsolateral and ventromedial tracts of spinal cord (delayed)
126
--- are tumor of meninges
meningiomas
most common intracranial tumor in cats and dogs, rare in horses
more common rostrally
most benign Grade 1, grade III very rare
127
meningiomas are most common in
Most common intracranial neoplasm in cats and dogs
* Very rare in horses and ruminants
usually benign but cause compression of brain
128
4 subtypes of meningioma tumors
histologically different but behave similarly- benign
129
tumor of gilial cells are
Astrocytomas Oligodendrogliomas
short faced breeds some cat, cattle and horses
Grossly well demarcated BUT infiltrative histologically
130
--- type of brain cancer is Grossly well demarcated BUT infiltrative
histologically
glioma
Astrocytomas Oligodendrogliomas
131
what type of tumor
intraventricular tumor
Choroid plexus tumors
* Papilloma or Carcinoma
* Golden retriever predisposed
* Reported sporadically in horses and cattle
132
what type of intraventricular tumor is common in golden retrievers
choroid plexus tumor
133
type of intraventricular tumor
Ependymoma
* Uncommon tumors in dogs, cats,
horses, cattle
134
name some metastatic neoplasia in brain of dog
Hemangiosarcoma, carcinoma, malignant melanoma
135
common metastatic brain cancers of cats
Mammary adenocarcinoma, lymphoma
136
paraparetic
partial paralysis of the lower limbs.
137
You perform a physical exam and you find dimpling of the skin overlying the lumbar region of the spinal column (image), an easily expressed bladder, absent anal sphincter tone, and analgesia to the skin of the perineum.
Given the signalment of the patient and the location of the lesion, what do you think is the most likely disease process ---
, most likely specific type of disease ---?
congenital
neural tube defect
138
On histologic examination of the spinal cord you see the changes depicted below:
What area of the spinal cord does this represent ---?
What characteristic pathologic change to neurons are the arrows pointing to?
white matter
axonal swelling (spheroids)
139
What is the pathogenesis of this lesion?
Degeneration of the nucleus pulposus, annulus fibrosis and/or dorsal longitudinal ligament ---> extrusion or herniation of disc material into spinal canal --> trauma to spinal cord and occlusion of blood vessels --> demyelination --> leukomalacia, hemorrhage (and poliomalacia if severe enough)
140
What is the name of this disease?
IVDD
Intervertebral disc disease
141
What serologic test(s) will you submit with the serum sample you collected antemortem, given the nature and distribution of the gross lesions in the spinal cord?
Equine herpes virus 1 and 4
Sarcocytis neurona
Equine Eastern Encephalitis virus
West Nile virus
Equine herpes virus 1 and 4
Sarcocytis neurona
142
a six year old thoroughbred gelding presents to you with signs of weakness over the past week that have now progressed to severe ataxia
On histologic examination of the spinal cord you find the changes below:
What etiologic agent is responsible for this disease?
What is the disease called?
Sarcocystis neurona
Equine protozoal myeloencephalitis (EPM)
143
What disease process do you suspect this represents?
what neoplasm does this most likely represent?
neoplasia
Peripheral nerve sheath tumor
## Footnote
Anatomic location and Gross: Multiple masses arising at the spinal nerve roots
Histology: Slender, fusiform cells arranged in bundles and plexiform nodules with bland oval nuclei.
