Pathology Ii - Third Exam

Front 1

dilation of the ventricles in the brain caused by obstruction within the ventricular system

Back 1

hydrocephalus

Front 2

what are three etiologies of hydrocephalus?

Back 2

all are obstruction of CSF flow
1. congenital
2. inflammation
3. neoplasia (primary or secondary)

Front 3

why do the ventricles dilate in hydrocephalus?

Back 3

pressure atrophy of the brain

Front 4

formation of a fluid-filled cavity in the cerebrum caused by necrosis and loss of the nervous tissue

Back 4

porencephaly

Front 5

a severe form of porencephaly in which most of the white matter is lost and the lateral ventricles expand to fill the space

Back 5

hydranencephaly

Front 6

what is the most common cause of hydranencephaly/porencephaly?

Back 6

viral infection in utero such as blue tongue virus, border disease, and BVD.

Front 7

failure of the cerebellum to develop to normal size

Back 7

cerebellar hypoplasia

Front 8

what is the most common cause of cerebellar hypoplasia in
bovines?
cats?

Back 8

- bovines: BVD
- cats: panleukopenia virus

Front 9

a calf or kitten with a hypermetric gait, tremors, and loss of balance may have what neurological defect?

Back 9

cerebellar hypoplasia

Front 10

atrophy of the cerebellum after the organ has developed to normal size. in what animal is this most frequently seen?

Back 10

cerebellar abiotrophy. dogs.

Front 11

what are two diseases of lambs is caused by copper malnutrition in pregnant sheep?

Back 11

1. swayback (hydranencephaly)
2. enzootic ataxia

Front 12

what is the difference between enzootic ataxia and swayback (both are diseases of lambs caused by copper insufficiency during gestation)?

Back 12

- swayback (hydranencephaly) is necrosis and degeneration of white matter
- enzootic ataxia is axonal degeneration (gray matter)

Front 13

a congenital condition where myelin fails to generate. in what three species is this most common?

Back 13

hypomyelinogenesis
- pigs
- dogs
- sheep (Border disease)

Front 14

what is border disease? species? clinical signs?

Back 14

- congenital hypomyelinogenesis
- sheep
- "hairy shakers." animals that tremor and whose wool looks like hair

Front 15

failure of the spine to close during fetal development

Back 15

spina bifida

Front 16

what are the two most common lesions caused by spina bifida?

Back 16

1. meningocele - meninges protruding out of the spine
2. meningomyelocele - spinal cord protrudes out of the spine

Front 17

dilation of the central canal of the spinal cord

Back 17

hydromyelia

Front 18

formation of a fluid-filled cavity in the parenchyma of the spinal cord

Back 18

syringomyelia

Front 19

what are the two general pathogenic processes of edema in the nervous system?

Back 19

1. intracellular (vasogenic)
2. extracellular (cytotoxic)

Front 20

how does the brain look with severe edema?

Back 20

swelling of the brain with flattening of the gyri. the cerebellum is forced into the foramen magnum and becomes narrowed into a cone shape.

Front 21

what are three etiologies of vasogenic (intracellular) edema of the brain?

Back 21

1. neoplasia
2. inflammation
3. trauma

Front 22

neurologic disease occurring secondarily to liver disease

Back 22

hepatoencephalopathy

Front 23

what are three etiologies of cytotoxic (extravascular) edema of the brain?

Back 23

1. lead toxicity
2. salt toxicity
3. hepatoencephalopathy

Front 24

histologically, how does cerebellar hypoplasia compare to a normal cerebellum (H&E stain)?

Back 24

- normal cerebellar gray matter has basophilic axonal bodies and appears blue
- with hypoplasia, the axonal bodies are destroyed and the gray matter stains an eosinophilic pink.

Front 25

how does hypomyelinogenesis appear histologically (H&E stain)?

Back 25

the normal brain has homogeneously dispersed neurons with clear zones where myelin was before slide preparation. Hypomyelinogenesis appears as distorted clear zones, often with axonal bodies with no myelin.

Front 26

This section of spinal cord has what defect?

Back 26

hydromyelia

Front 27

this section of spinal cord has what defect?

Back 27

syringomyelia

Front 28

This section of brain has what defect?

Back 28

edema

Front 29

These are two different magnifications of the same brain section. What disease is present?

Back 29

lysosomal storage disease

Front 30

The section of brain on the left is normal. That is wrong with the section on the right?

Back 30

axonal degeneration

Front 31

What is wrong with this spinal cord? What is the main etiology of this lesion?

Back 31

Wallerian degeneration (lost axons and demyelination). Usually caused by spinal cord compression.

Front 32

what is the difference between the spinal cord section on the left from the section on the right?

Back 32

the left is normal (basophilic), the right is necrotic neurons (eosinophilic)

Front 33

the presence of yellow discoloration in the white matter is indicative of what disease?

Back 33

polioencephalomalacia

Front 34

describe the lesions in this brain section. What infectious agent could cause this?

Back 34

- severe edema and hemorrhage
- swollen gyri
- Clostridium perfringens type D

Front 35

this section of cerebrum is showing what disease?

Back 35

meningitis

Front 36

a bacterial infection is causing what lesions in this brain?

Back 36

choroiditis and ependymitis

Front 37

the circle pattern of basophilic dots in this brain section is which type of lesion? what is one infectious agent that can cause this?

Back 37

abscess caused by Listeria monocytogenes

Front 38

What lesions are present in this cerebral section? What is the disease and a common causative agent?

Back 38

- thrombosis of the blood vessels
- multiple small abscesses
- this is thrombotic meningoencephalitis caused by Histophilus somni

Front 39

what is the lesion in this brain section? what is it caused by?

Back 39

- lymphocytic and plasma cell perivascular cuffs
- caused by a viral infection

Front 40

In this brain section, what are the large, eosinophilic lesions called? What causes them?

Back 40

- Negri bodies
- Rabies

Front 41

In this section of spinal cord, what are the circular pink lesions?

Back 41

they are a single worm (cut in multiple planes). Paralaphostrongylus tenuis

Front 42

this dorsal section of a brain has what lesion?

Back 42

choroid plexus tumor

Front 43

In this sagittal section of the spinal cord, what lesions are present (note that the blue color is an artifact of photography)

Back 43

dura ossification

Front 44

a sharply delineated pale, tan, or yellow lesion in the brain could be what?

Back 44

infarction

Front 45

disease of cats of unknown cause that produce areas of infarction and necrosis in the cerebrum

Back 45

feline ischemic encephalopathy

Front 46

what causes focal infarction in the brain and spinal cord? what are two common causes

Back 46

- emboli
1. bacterial (e.g. Histophilus somni)
2. fibrocartilagenous from rupture of intervertebral disc material

Front 47

an embolus of intervertebral disc material in the spinal cord is called what? what is a clinical sign in animals with this lesion?

Back 47

- fibrocartilagenous embolism
- animals would show posterior paralysis due to infarction of the spinal cord

Front 48

what is the usual cause of hemorrhage in the CNS?

Back 48

trauma

Front 49

what are two non-traumatic causes of hemorrhage in the CNS?

Back 49

1. leukoencephalomalacia in horses
2. Clostridium perfringens type D in sheep

Front 50

a group of inherited diseases each caused by absence or deficiency of a single enzyme in a pathway that breaks down cellular organelles in lysosomes

Back 50

lysosomal storage diseases

Front 51

what are the four types of lysosomal storage disease?

Back 51

1. lipidosis
2. mucopolysaccharidosis
3. glycoproteinosis
4. ceroid-lipofuscinosis

Front 52

comment on the Mendelian genetics of lysosomal storage disease

Back 52

it is an autosomal homozygous recessive disease.

Front 53

besides genetics, what is another common etiology of lysosomal storage disease?

Back 53

ingestion of poisonous plants such as Astragalus (locoweed) or swainsoma.

Front 54

what are clinical signs associated with lysosomal storage disease?

Back 54

- clinical signs appear shortly after birth
- ataxia, incoordination, tremors
- death after many months

Front 55

how do neurons with lysosomal storage disease appear microscopically?

Back 55

neurons are filled with substrate that is often foamy or granular in appearance

Front 56

what general group of diseases are caused by prions?

Back 56

transmissible spongiform encephalopathy

Front 57

what is neuropil?

Back 57

a type of glial cell located in the brain. they are the "pink background" in an H&E stain of brain tissue.

Front 58

what lesions are seen macroscopically and microscopically in transmissible spongiform encephalopathy?

Back 58

- no gross lesions are present
- vacuoles are present in the neuropil

Front 59

what is Nissl substance?

Back 59

ribosomes within neurons

Front 60

the dispersion of Nissl substance in a neuron, giving the cytoplasm a glassy appearance, caused by axonal degeneration

Back 60

chromatolysis

Front 61

compressive necrosis and degeneration of myelin and axons of the spinal cord

Back 61

Wallerian degeneration

Front 62

in which two species is Wallerian degeneration most common?

Back 62

dogs and horses

Front 63

what is seen microscopically in Wallerian degeneration?

Back 63

- lost axons
- fragmented and swollen myelin sheaths, leaving vacuoles in the white matter
- macrophages in the empty axon sheaths
- reactive astrocytes

Front 64

what are two common etiologies of Wallerian degeneration caused by compression of the spinal cord?

Back 64

1. herniation of an intervertebral disc
2. cervical vertebral stenotic myelopathy

Front 65

what is Wobbler Syndrome? What microscopic lesion is present?

Back 65

- cervical vertebral stenotic myelopathy of the horse
- malformation of the cervical vertebra, causing stenosis of the spinal canal and pressure necrosis of the spinal cord
- lesions will appear as Wallerian degeneration

Front 66

what is the most important class of toxin that causes axonal degeneration?

Back 66

organophosphates

Front 67

a disease of most commonly horses, but also dogs, with an unknown cause, characterized by diffuse Wallerian degeneration of the spinal cord

Back 67

degenerative myelopathy

Front 68

how do necrotic neurons appear on an H&E stain compared to normal neurons?

Back 68

- normal are blue
- necrotic are red

Front 69

A disease of the brain, characterized by associated edema and softening of the gray matter and necrosis.

Back 69

polioencephalomalacia

Front 70

what is the most common cause of polioencephalomalacia in ruminants? what are clinical signs in these animals?

Back 70

- thiamine deficiency
- blind, paresis → recumbency, grinding of teeth, opisthotonus (back muscle spasm) and extensor rigidity

Front 71

besides thiamine deficiency, what are three causes of polioencephalomalacia in ruminants (and pigs)?

Back 71

1. salt poisoning
2. dehydration → salt poisoning
3. lead toxicity

Front 72

what is the usual result of ischemia or hypoxia to neural tissue?

Back 72

necrosis

Front 73

neuronal necrosis in the foal caused by hypoxia and ischemia during dystocia

Back 73

neonatal maladjustment syndrome

Front 74

unique to the horse, a necrosis of the white matter of the brain with softening, caused by corn spoiled with Fusarium mold.

Back 74

leukoencephalomalacia

Front 75

what is the gross appearance of leukoencephalomalacia? what species are affected? clinical signs?

Back 75

- cerebral cortical white matter is edematous and thickened with hemorrhage and yellowing
- this disease is unique to horses
- sudden onset of staggering, weakness, circling, depression, and head pressing
- seizures and hyperexcitability → death

Front 76

what lesions are observed in a neurological infection of Clostridium perfringens type D in sheep?

Back 76

- secondary neuronal necrosis with hemorrhage in the basal ganglia, cerebellar peduncles, and internal capsule
- bilaterally symmetrical
- focal symmetrical encephalomalacia

Front 77

a disease of unknown cause in the horse characterized by chromatolysis and necrosis of the neurons of the ventral horns of the spinal cord.

Back 77

equine motor neuron disease

Front 78

in pigs, caused by selenium toxicity, posterior paralysis and quadriplegia due to necrosis of the ventral horn of the cervical and lumbar spinal cord

Back 78

poliomyelomalacia

Front 79

inflammatory cells and lymphocytes surrounding a blood vessel in the CNS as a response to necrosis, ischemia, and inflammatory diseases

Back 79

perivascular cuffing

Front 80

inflammation of the leptomeninges, pia and arachnoid

Back 80

meningitis

Front 81

meningitis that has extended into the neuropil

Back 81

meningoencephalitis

Front 82

how do the meninges appear grossly with severe inflammatory meningitis?

Back 82

opaque white, yellow, or green

Front 83

what are the two major types of tooth germ tumors?

Back 83

1. ameloblastoma
2. odontoma

Front 84

comment on the malignancy of tooth germ tumors

Back 84

they are generally benign, but very proliferative.

Front 85

in which species do tooth germ tumors commonly occur?

Back 85

dog, cat, bovine

Front 86

failure to form enamel of the teeth

Back 86

enamel hypoplasia

Front 87

what causes enamel dysplasia in young dogs?

Back 87

distemper virus

Front 88

what non-infectious agent can cause destruction of the enamel? Pathogenesis?

Back 88

- fluorine
- calcuim fluoride makes the enamel more brittle, exposing the dentin (looks yellow)

Front 89

what is the most common cause of periodontal disease?

Back 89

tartar buildup on the teeth

Front 90

a cyst that forms when a salivary duct ruptures and saliva accumulates in the adjacent soft tissue

Back 90

mucocele

Front 91

a mucocele of the sublingual salivary gland that forms a cyst at the base of the tongue

Back 91

ranula

Front 92

inflammation of the salivary gland. Where is this most commonly found?

Back 92

-sialoadenitis
- corona virus in rats
- (mumps in people)

Front 93

what is the most common tumor of the salivary gland? Appearance?

Back 93

salivary gland adenocarcinoma
singular nodular node in the submandibular region

Front 94

comment on the malignancy of salivary gland adenocarcinomas

Back 94

highly metastatic, especially to the lungs

Front 95

what is the most common lesion of the esophagus?

Back 95

ulcers

Front 96

what is a major causative agent of ulcers in the bovine esophagus?

Back 96

- BVD

Front 97

how to ulcers appear in the esophagus?

Back 97

they are linear

Front 98

what is "choke"?

Back 98

annular ulcers of the equine esophagus caused by dry food getting stuck and causing pressure necrosis. Can perforate

Front 99

what are four etiologies of proliferative, caseous lesions of the esophagus?

Back 99

1. avian pox
2. hypovitaminosis A
3. candida (thrush)
4. trichomonas

Front 100

what causes thrush? Where is the lesion?

Back 100

- candida
- usually lesions on the tongue, but anywhere in the oral cavity

Front 101

what are four etiologies for respiratory squamous metaplasia in birds?

Back 101

Candida, Trichomonas, Pox Virus, Hypovitaminosis A

Front 102

why does hypovitaminosis A cause proliferation of the avian esophagus?

Back 102

it causes squamous metaplasia, which proliferates and keratinizes

Front 103

dilation of the esophagus, commonly associated with a persistent right aortic arch

Back 103

megaesophagus

Front 104

what causes Edema disease of swine? Where is the edema?

Back 104

- E. coli
- stomach, subcutis, mesentery, and other sites

Front 105

what dietary deficiency can cause edema of the stomach wall and/or intestinal wall

Back 105

hypoproteinemia

Front 106

what are four common causes of gastric ulcers?

Back 106

1. idiopathic
2. Gastrophilus larvae in horses
3. stress
4. steroids or NSAIDs

Front 107

what are three causes of megaesophagus?

Back 107

1. myasthenia gravis
2. persistent right aortic arch
3. dermatomyositis

Front 108

what are two common causes of gastric hemorrhage

Back 108

1. heavy metals
2. uremia

Front 109

in which species do bloat most commonly occur?

Back 109

horses and captive primates

Front 110

what is the most common site of ulcers in horses? Etiology? Severity of disease?

Back 110

- the margo plicatus
- Gastrophilus larvae
- incidental finding

Front 111

what to bots look like in the horse stomach?

Back 111

yellow bumps at the margo plicatus

Front 112

at necropsy, how do you differentiate whether a stomach has hemorrhage or if it has congestion?

Back 112

- congestion is light and diffuse
- hemorrhage is usually bright red and sharply demarcated

Front 113

what is melena?

Back 113

a black colored blood in the GI tract (usually in the stools), caused by digestion of the blood

Front 114

how can renal failure lead to melena?

Back 114

renal failure → uremia → gastric ulcers → hemorrhage into stomach → melena

Front 115

what is volvulus?

Back 115

twisting of the stomach or intestine around the axis of the mesentery

Front 116

what is a fancy name for bloat?

Back 116

gastric distention

Front 117

how is bloat commonly caused in horses?

Back 117

grain overload causes excessive fermentation and bloat. Can lead to rupture

Front 118

what is a common sequela to gastric distention in dogs?

Back 118

volvulus

Front 119

what is a lesion resulting from gastric torsion that involves a place other than the stomach?

Back 119

splenic ischemia

Front 120

swallowing of air

Back 120

aerophagia

Front 121

what are two common causes of a displaced abomasum in cattle?

Back 121

1. bloat
2. parturition

Front 122

what is the most common species and pathogenesis of a stomach rupture?

Back 122

horses from intestinal obstruction or gastric distention

Front 123

plant foreign body in the stomach

Back 123

phytobezoar

Front 124

fancy name for a hairball

Back 124

trichobezoar

Front 125

how can a tricho- or phytobezoar be a problem?

Back 125

if they obstruct the pylorus, they can cause gastric distention

Front 126

what is a common cause of gastric mucosal hyperplasia in
- cattle?
- horses?

Back 126

- cattle: Ostertagia
- horses: Trichostrongylus

Front 127

what does an abomasum infected with Ostertagia look like?

Back 127

bumps on the mucosa

Front 128

what are three common neoplasias of the stomach (species)

Back 128

1. Gastric carcinoma (dogs)
2. Squamous cell carcinoma (horse)
3. Lymphoma (dog, cat, cattle)

Front 129

what does a gastric carcinoma look like? Malignancy?

Back 129

very fibrous and proliferative. Very malignant and poor prognosis

Front 130

why can horses get squamous cell carcinoma of the stomach, but not usually dogs? Comment on malignancy

Back 130

because horses have a non-glandular portion of their stomach. These are very malignant because they commonly spread to the intestines and colic

Front 131

comment on the gross appearance of gastric lymphoma

Back 131

homogeneous, tan, soft tissue. Can fill the stomach and outline the shape and cause obstruction

Front 132

tumor of smooth muscle

Back 132

leiomyoma

Front 133

what does a leiomyoma of the GI tract look like. Prognosis

Back 133

a coarse, single-nodular tumor that bulges into the lumen. Can be surgically removed.

Front 134

inflammation of the choroid plexus

Back 134

choroiditis

Front 135

inflammation of the epithelioid tissue lining the ventricles of the brain and spinal cord

Back 135

ependymitis

Front 136

what is the most common pathogenic source of bacterial infection in the CNS?

Back 136

hematogenous

Front 137

Neural Listeriosis in ruminants
- how does it get into the CNS
- lesions
- clinical signs

Back 137

- enters the brainstem through the mouth via the cranial nerves secondary to trauma to the oral cavity
- purulent encephalitis with microabscesses
- circling, head pressing, paralysis of CN-VII causing unilateral drooping of the ear, lip, or eyelid

Front 138

thrombotic encephalitis in cattle is caused by what?

Back 138

Histophilus somni

Front 139

Histophilus somni in cattle (neurologic infection)
- disease name
- lesions
- clinical signs

Back 139

- thrombotic meningoencephalitis
- localization in the brain, producing a vasculitis with thrombosis of cerebral vessels. Grossly, multifocal hemorrhages which are infarcts
- arthritis, pneumonia; death is usually rapid

Front 140

microscopically, what are three lesions associated with CNS viral infection?

Back 140

- lymphocytic and plasma cell perivascular cuffing
- chromatolysis and necrosis of neurons
- glial nodules - proliferation and aggregation of microglia

Front 141

what are Negri bodies?

Back 141

eosinophilic intracytoplasmic accumulations of Rabies virus

Front 142

how is Rabies definitively diagnosed?

Back 142

microscopically, by the presence of Negri bodies in the brain

Front 143

a highly contagious and zoonotic infection of pigs that can lead to fatal neurologic disease

Back 143

pseudorabies

Front 144

pseudorabies:
- causative agent
- host species
- clinical signs

Back 144

- a herpes virus
- pigs
- some pigs are asymptomatic; young pigs develop severe neurologic disease; older pigs develop mild respiratory disease

Front 145

neurological disease of the horse transmitted through mosquito bites

Back 145

equine viral encephalitis

Front 146

equine viral encephalitis
- what is the infectious agent?
- how is it acquired?
- clinical signs

Back 146

- an arbovirus
- acquired by mosquito bites
- drowsiness, blindness, circling, and death

Front 147

describe the microscopic lesions of retroviral neurologic infection in goats and sheep.

Back 147

- perivascular cuffs
- demyelination

Front 148

a brain section of a goat shows demyelination and perivascular cuffs. what could this indicate?

Back 148

retroviral infection such as caprine arthritis encephalitis

Front 149

caprine arthritis encephalitis
- causative agent
- clinical signs
- microscopic lesions

Back 149

- a retrovirus
- in goat kids, encephalomyelitis; in adult goats, arthritis and interstitial pneumonia
- in a brain section, demyelination and perivascular cuffs

Front 150

a retroviral disease of sheep similar to caprine arthritis encephalitis

Back 150

visna

Front 151

canine distemper
- causative agent
- lesions in the CNS
- characteristic clinical sign

Back 151

- a morbillivirus
- neuronal necrosis in the gray matter and demyelination in the white matter; basophilic intranuclear and intracytoplasmic viral inclusion bodies in the neurons and astrocytes.
- (variable clinical signs but) one common clinical sign is myoclonus (repetitive contraction) of the masticatory muscles.

Front 152

a dog presents with spasms of the masticatory muscles and severe neurologic disorders. After euthanasia, a brain section shows neuronal necrosis in the gray matter and demyelination in the white matter. Also, intranuclear and intracytoplasmic inclusion bodies were found in the neurons and astrocytes. What disease did this dog have?

Back 152

canine distemper

Front 153

a viral infection of the horse that is most well-known for causing abortion, but also can cause vasculitis and hemorrhage in the spinal cord and brain

Back 153

equine herpesvirus 1

Front 154

a poliomyelitis and encephalitis affecting horses is caused by which infective agent?

Back 154

west nile virus

Front 155

what is the typical lesion of a fungal infection in the nervous system?

Back 155

granulomatous or pyogranulomatous inflammation

Front 156

what is the most important fungal disease in animals affecting the nervous system? In which species does this occur? describe pathogenesis and diseases

Back 156

- Cryptococcus (a yeast)
- cats
- infection of the nasal mucosa extends into the brain, producing meningitis or meningoencephalitis

Front 157

name three parasites that infect nervous system and their hosts?

Back 157

1. Sarcocystis neurona - horses
2. Paralaphostrongylus tenuis - sheep and llamas
3. Halicephalobus gingivalis - horses

Front 158

describe the lesions observed with parasitic infection of the nervous system

Back 158

- multifocal inflammation and necrosis of white and gray matter
- eosinophils

Front 159

what type of infection is associated with eosinophils?

Back 159

parasites such as protozoa and helminthes

Front 160

equine protozoal myelitis
- causative agent
- microscopic lesions
- clinical signs

Back 160

- Sarcocystis neurona
- multifocal inflammation and necrosis of white and gray matter; eosinophils
- paralysis, paresis, ataxia

Front 161

Paralaphostrongylus tenuis
- animals affected
- carrier
- clinical signs

Back 161

- sheep and llamas
- white-tailed deer are asymptomatic carriers
- infection of the spinal cord, leading to paresis, paralysis, and ataxia

Front 162

Halicephalobus gingivalis
- host species
- what does it do?

Back 162

- horses
- infects the kidney and nasal cavity. It can penetrate the skin and migrate hematogenously to the brain

Front 163

an idiopathic disease of dogs characterized by lesions (often discolored) of the white matter and consists of lymphocytes, plasma cells, and macrophages

Back 163

granulomatous meningoencephalitis

Front 164

what neurologic disease of horses is characterized by incontinence, perineal anesthesia, and tail paralysis?

Back 164

cauda equina neuritis

Front 165

name two types of glial cell tumors and their prevalence

Back 165

- astrocytoma - most common
- oligodendroglioma - very rare

Front 166

astrocytomas
- which animals are most commonly affected?
- location of tumors
- describe the lesions
- what is the main reason they cause clinical signs?

Back 166

- brachycephalic breeds of dogs
- cerebral cortex
- tan, gray, or white, and can range from well to poorly delineated
- they cause compression of surrounding tissue, which causes clinical signs

Front 167

tumors of the choroid plexus
- types of tumors
- appearance
- where are they usually located?

Back 167

- adenoma or adenocarcinoma
- very vascular and red grossly
- in the 4th ventricle

Front 168

a neoplasm on the surface of the brain

Back 168

meningioma

Front 169

what is the most common tumor of the CNS in the dog and cat? describe the lesion and location of the lesion.

Back 169

- meningioma
- white to gray fibrous mass on the surface of the brain
- ventral in dogs; dorsal in cats

Front 170

a tumor of the cells lining the ventricles of the CNS

Back 170

ependymoma

Front 171

what is the difference in appearance of a choroid plexus tumor and an ependymoma?

Back 171

a choroid plexus tumor is red and vascular; an ependymoma is gray, white, or tan

Front 172

name three tumors of the nervous system that originate from primitive neurons

Back 172

1. neuroblastoma
2. medulloblastoma
3. ganglioneuroma

Front 173

peripheral nerve sheath tumor
- what type of cells are neoplastic?
- species
- location of tumors

Back 173

- Schwann cells (note this is also called a Schwannoma)
- mainly dogs, more rarely cattle
- in dogs: skin and brachial plexus; cattle: intrathoracic nerves

Front 174

a dog presents with unilateral thoracic limb paralysis and firm masses under the skin near the axilla. What is it?

Back 174

peripheral nerve sheath tumor (Schwannoma)

Front 175

a horse at necropsy presents with hydrocephalus and large nodules obstructing the ventricles. What could these nodules be?

Back 175

cholesterol granuloma

Front 176

what is dural ossification?

Back 176

mineralized plaques in the dura of older dogs

Front 177

inflammation of the mouth

Back 177

stomatitis

Front 178

inflammation of the tongue

Back 178

glossitis

Front 179

inflammation of the gums

Back 179

gingivitis

Front 180

what usually occurs secondarily to a cleft palate in a neonate?

Back 180

aspiration pneumonia from colostrum/milk entering the nasopharynx. sucking may also be difficult

Front 181

what is the fancy name for a blister

Back 181

vesicle

Front 182

name four vesicular disturbances of the mouth, caused by reportable, contagious viral infections and the species in which they are found

Back 182

1. foot and mouth disease - pigs, cattle, sheep
2. vesicular stomatitis - horses, cattle, pigs
3. vesicular exanthema - pigs
4. swine vesicular disease - pigs

Front 183

a cat with ulcers in the mouth and an upper-respiratory infection probably has what?

Back 183

feline calici virus

Front 184

what causes cold sores in rhesus monkeys, but kills other monkeys like humans?

Back 184

Herpes B virus

Front 185

what are two autoimmune diseases of the dog and cat that produce a vesicular stomatitis?

Back 185

1. pemphigus vulgaris
2. bullous pemphigoid

Front 186

what are two rule-outs for ulcerations of the esophagus, small intestine, and mouth of cattle?

Back 186

1. BVD
2. malignant catarrhal fever

Front 187

what is bluetongue?

Back 187

an insect-transmitted orbivirus infection of sheep causing ulcers in the mouth and hemorrhages in the forestomach, coronet, and pulmonary artery

Front 188

what causes ulcers on the tongue and stomach secondary to renal failure?

Back 188

uremia

Front 189

ulcers in the mouth of dogs and cats caused by a hypersensitivity to parasitic infection

Back 189

eosinophilic granuloma complex

Front 190

gram-negative infection of fish and reptiles causing septicemia, and necrosis and hemorrhage of the mouth and other organs

Back 190

Aeromonas

Front 191

a pox virus infection of sheep and goats producing crusty lesions on the lips, face, and feet

Back 191

contagious ecthyma

Front 192

what is contagious ecthyma?

Back 192

a pox virus infection of sheep and goats producing crusty lesions on the lips, face, and feet

Front 193

in cattle, a parapox virus infection producing discrete circular, slightly raised lesions in the mouth and esophagus, usually an incidental finding.

Back 193

bovine papular stomatitis

Front 194

a gram-negative bacterial infection of young cattle, producing ulcerative and caseous proliferative lesions in the mouth and larynx. The organism is a secondary invader following trauma to the mucosa.

Back 194

Fusobacterium necrophorum

Front 195

bovine papular stomatitis
- etiology
- lesions
- malignancy

Back 195

in cattle, a parapox virus infection producing discrete circular, slightly raised lesions in the mouth and esophagus, usually an incidental finding.

Front 196

Fusobacterium necrophorum
- species infected
- lesions
- etiology

Back 196

a gram-negative bacterial infection of young cattle, producing ulcerative and caseous proliferative lesions in the mouth and larynx. The organism is a secondary invader following trauma to the mucosa

Front 197

what diseases in the mouth of cattle are produced by
- Actinobacillus
- Actinomyces

Back 197

- Actinobacillus: wooden tongue
- Actinomyces: lumpy jaw

Front 198

proliferation of the gums, usually in response to chronic periodontal disease in dogs

Back 198

gingival hyperplasia

Front 199

what is the most common cause of gingival hyperplasia?

Back 199

periodontal disease

Front 200

what are four types of neoplasias of the small intestine

Back 200

1. lymphosarcoma
2. leiomyoma/leiomyosarcoma
3. adenocarcinoma
4. gastrointestinal stromal tumor

Front 201

what is the appearance of small intestinal lymphoma

Back 201

- usually not constrictive
- tan and firm

Front 202

what the appearance of adenocarcinoma in the small intestine

Back 202

annular band

Front 203

what is a gastrointestinal stromal tumor in the SI?

Back 203

tumor of the interstitial cells of Cajal, which are part of the autonomic nervous system and located in the myenteric plexuses of the intestinal wall

Front 204

tumor of the interstitial cells of Cajal, which are part of the autonomic nervous system and located in the myenteric plexuses of the intestinal wall

Back 204

gastrointestinal stromal tumor

Front 205

what is the appearance of a leiomyoma of the SI

Back 205

distinct tan nodule beneath the mucosa.

Front 206

in what species is volvulus of the SI most common?

Back 206

horse

Front 207

what lesions are caused by volvulus of the SI? Why can animals die?

Back 207

no venous drainage; so congestion, edema, necrosis, endotoxic shock, death

Front 208

a telescoping of the intestine into itself

Back 208

intussusception

Front 209

what is the most common cause of intussusception?

Back 209

secondary to hypermotility

Front 210

what lesions are associated with intussusception? Clinical signs

Back 210

it is a local lesion, so it can be removed. Pain, colic.

Front 211

condition where the intestine is trapped by a band of connective tissue

Back 211

strangulation/incarceration

Front 212

what is the usual cause of SI strangulation/incarceration in horses?

Back 212

most commonly with lipomas in the mesentery

Front 213

entrapment of the intestine in constricted openings such as enlarged inguinal rings, an open umbilicus or a ruptured diaphragm

Back 213

hernia

Front 214

what are four non-infectious rule-outs for small intestine that have diffuse congestion, hemorrhage, and edema of the affected bowel?

Back 214

1. hernia
2. strangulation/incarceration
3. volvulus
4. torsion

Front 215

a tumor that looks like an annular band in the SI is probably what?

Back 215

adenocarcinoma

Front 216

what is the difference between a torsion and a volvulus?

Back 216

torsion is twisting on itself; volvulus is a rotation on its mesenteric axis

Front 217

what are two bacterial causes of excess fluid within a normal intestine?

Back 217

E. coli, Clostridium perfringens type D

Front 218

what are three viral causes of excess fluid within a normal intestine?

Back 218

rotavirus, coronavirus, panleukopenia

Front 219

what is a protozoal cause of excess fluid within a normal intestine?

Back 219

cryptosporidia

Front 220

what are two non-infectious diseases of the small intestine characterized by excess fluid, but not usually hemorrhage?

Back 220

1. lymphangiectasia
2. inflammatory bowel disease

Front 221

in which species is E. coli an important infection of the intestines of neonates?

Back 221

pigs, ruminants, foals

Front 222

how do coronaviruses and rotaviruses lead to excess fluid in the otherwise normal intestine of a neonate?

Back 222

the virus destroys the epithelial cells on the villi, leading to malabsorption and diarrhea

Front 223

what is the "classic lesion" of a rotavirus or a coronavirus infection of the small intestine?

Back 223

villous atrophy

Front 224

how does cryptosporidia cause excess fluid in the otherwise normal small intestine?

Back 224

attaches to the microvillus border of the intestinal epithelial cells

Front 225

what is a common cause of Clostridium perfringens type D enterotoxemia in sheep?

Back 225

a change in feed from poor quality to good quality, which leads to bacterial overgrowth

Front 226

dilation of the lacteals in the intestinal wall of the dog resulting in malabsorption

Back 226

lymphangiectasia

Front 227

what is inflammatory bowel disease?

Back 227

an allergic enteritis of the dog and cat of unknown cause, probably from dietary antigens, that causes excess fluid of the normal SI and diarrhea

Front 228

a parvovirus infection of the cat, causing hypoplasia of all cell lines in the bone marrow and necrosis of the intestinal crypts

Back 228

panleukopenia

Front 229

in inflammatory bowel disease, what is the scientific term for the most common form for the disease?

Back 229

lymphoplasmacytic enteritis

Front 230

macrophages in the mucosa of the large intestine along with ulcers

Back 230

ulcerative colitis/histiocytic ulcerative colitis

Front 231

what is the lesion associated with ulcerative colitis?

Back 231

macrophages in the mucosa

Front 232

a bacterial infection of primates producing an ulcerative and sometimes hemorrhagic colitis

Back 232

Shigella

Front 233

what infection causes ulcerative colitis in the horse?

Back 233

Salmonella

Front 234

what breed of dogs is predisposed to ulcerative colitis?

Back 234

Boxers

Front 235

what lesions are observed with salmonellosis of the large intestine?

Back 235

ulcerative and/or hemorrhagic or fibrinous or fibrinonecrotic

Front 236

name three bacteria involved in fibrinous/necrotic/fibrinonecrotic lesions of the large intestine and their associated hosts

Back 236

1. Salmonella - horses, pigs (SI in cattle)
2. Brachyspira hyodysenteriae (swine dysentery) - pigs
3. Yersinia pseudotuberculosis - primates, rodents, occasionally cattle

Front 237

name three parasites involved in fibrinous/necrotic/fibrinonecrotic lesions of the large intestine and their associated hosts

Back 237

1. Histomonas meleagridis - turkeys
2. Trichuris (whipworms) - pig and dog
3. heavy infections with small strongyles - horses

Front 238

name two non-infectious causes of fibrinous/necrotic/fibrinonecrotic lesions of the large intestine in horses

Back 238

1. certain oral antibiotics
2. NSAIDs

Front 239

what is the lesion associated with Histomonas infection of the lower GI tract in birds?

Back 239

caseous necrosis of the cecum

Front 240

what common parasite causes fibrinous colitis in pigs and dogs?

Back 240

whipworms

Front 241

what is "Colitis X"?

Back 241

a disease in the horse, probably caused by an overgrowth of Clostridia bacteria. It produces hemorrhage and edema in the wall of the colon but no blood in the feces.

Front 242

a disease in the horse, probably caused by an overgrowth of Clostridia bacteria, producing hemorrhage and edema in the wall of the colon but no blood in the feces.

Back 242

Colitis X

Front 243

what are three etiologies of hemorrhage of the large intestine?

Back 243

1. Colitis X - horse
2. DIC
3. Anticoagulant toxicosis

Front 244

in ruminants, a disease caused by Mycobacterium avium ss paratuberculosis, which causes thickening of the mucosa due to granulomatous inflammation.

Back 244

Johne's disease

Front 245

what is Johne's disease

Back 245

in ruminants, a disease caused by Mycobacterium avium ss paratuberculosis, which causes thickening of the mucosa due to granulomatous inflammation.

Front 246

what type of neoplasias can cause proliferative disorders in the colon?

Back 246

1. lymphoma
2. adenocarcinoma
3. leiomyoma
4. gastrointestinal stromal tumor

Front 247

what are the two main proliferative lesions of the large intestine?

Back 247

1. Johne's disease
2. neoplasia

Front 248

obstruction of the colon

Back 248

impaction

Front 249

what things usually cause impaction of the large intestine?

Back 249

feces, coarse feed, foreign bodies, (enteroliths and sand in horses)

Front 250

mineralized concretions in the bowel lumen that build in size over time, which can cause bowel impaction in horses

Back 250

enteroliths

Front 251

no anus

Back 251

atresia ani

Front 252

atresia ani

Back 252

no anus

Front 253

a congenital defect in cattle where the colon ends in a blind sac somewhere other than the anus

Back 253

atresia coli

Front 254

abnormal dilation of the colon

Back 254

megacolon

Front 255

what is thought to cause megacolon?

Back 255

spinal disc disease → loss of innervation

Front 256

what is a melanoma? Where are they found in the body? Comment on malignancy.

Back 256

- tumor of melanocytes
- found in the oral cavity of the dog and skin of many species
- 90% are malignant and survival time is 6 months

Front 257

name six neoplasias of the upper GI tract and the species in which they are commonly found

Back 257

1. melanoma - dogs
2. squamous cell carcinoma - cats (tongue) and dogs (tonsil)
3. fibrosarcoma - dogs and cats
4. Epulis - dog
5. papilloma - dog (oral), cattle (rumen)
6. tooth germ cell tumor - dog, cat, cattle

Front 258

squamous cell carcinoma of the upper GI tract:
where are they found in the cat? Dog?
Comment on malignancy

Back 258

- usually on the tongue of the cat
- tonsils of the dog
- invasive, but slow to metastasize. More malignant in the dog tonsil than in the oral cavity

Front 259

what is an epulis? Where does it originate?

Back 259

a benign tumor of the gingiva in the dog that resembles gingival hyperplasia. It aries from the periodontal ligament.

Front 260

a benign tumor of the gingiva in the dog arising from the periodontal ligament

Back 260

epulis

Front 261

In the dog, proliferation of the gums: what are two rule-outs?

Back 261

- gingival hyperplasia
- epulis (a neoplasm of the periodontal ligament)

Front 262

what is the fancy name for a wart? What causes it? Where they can be found in the GI system (species)?

Back 262

- papilloma
- papilloma virus infection
- oral cavity of the dog and rumen of cattle

Front 263

a rare disease of the dog that is similar to carcinoma grossly in which the stomach wall is infiltrated with eosinophils and fibrosis

Back 263

eosinophilic gastroenteritis

Front 264

eosinophilic gastroenteritis
- species
- lesions

Back 264

a rare disease of the dog that is similar to carcinoma grossly in which the stomach wall is infiltrated with eosinophils and fibrosis

Front 265

a nematode parasite of the horse that burrows into the glandular stomach producing nodules with a central pore

Back 265

Draschia megastoma

Front 266

Draschia megastoma
- what is it?
- species affected
- gross lesions observed

Back 266

- a nematode
- horse
- nodules with a central pore in the glandular stomach

Front 267

what is a common sequela to grain overload in ruminants?

Back 267

bloat

Front 268

what two basic nutrients can cause bloat in the rumen?

Back 268

- CHO
- proteins (from legumes)

Front 269

why can grain overload lead to ulcers in the rumen

Back 269

because lactic acid buildup damages the rumen mucosa

Front 270

what is a bloat line?

Back 270

a line of demarcation in the esophageal mucosa at the thoracic inlet, with the cranial esophagus being congested and the caudal esophagus being blanched and pale

Front 271

a line of demarcation in the esophageal mucosa at the thoracic inlet, with the cranial esophagus being congested and the caudal esophagus being blanched and pale

Back 271

bloat line

Front 272

in ruminants, what two infectious agents can be associated with lesions secondary to bloat?

Back 272

1. Fungi
2. Fusobacterium

Front 273

what do the gross lesions of a fungal infection of the rumen look like?

Back 273

circular lesions with a red rim

Front 274

what important bacterial infection of large animals is known to produce ulcers, hemorrhage, or fibrinous lesions of the intestines?

Back 274

Salmonella

Front 275

what produces ulcers in the Peyer's patches of cattle?

Back 275

BVD

Front 276

an important cause of ulcers in reptiles

Back 276

amoeba, especially entamoeba

Front 277

an important disease of young poultry and game birds caused by Clostridium colinum.

Back 277

ulcerative enteritis

Front 278

ulcerative enteritis in birds
- causative agent
- lesions

Back 278

- Clostridium colinum
- GI ulcers and multifocal yellow foci in the liver

Front 279

fibrinous enteritis of the mammalian GI tract is almost always what?

Back 279

Salmonellosis

Front 280

an important disease of chickens caused by Clostridium perfringens type A that produces diffuse necrosis of the GI tract with a fibrinonecrotic pseudomembrane

Back 280

necrotic enteritis

Front 281

necrotic enteritis in birds
- causative agent
- species affected
- lesion

Back 281

- Clostridium perfringens type A
- chickens
- diffuse necrosis of the GI tract with a fibrinonecrotic pseudomembrane

Front 282

what does DIC stand for?

Back 282

disseminated intravascular coagulation

Front 283

how does heavy metal toxicosis affect the small intestine?

Back 283

causes hemorrhage

Front 284

an important virus of dogs and cats that causes hemorrhagic enteritis in dogs and panleukopenia and a non-hemorrhagic enteritis in cats?

Back 284

parvovirus

Front 285

how does parvovirus infection cause disease in dogs?

Back 285

it destroys intestinal crypt cells leading to villous collapse and ulceration. this produces an hemorrhagic enteritis.

Front 286

how does parvovirus infection cause disease in the GI tract of cats? what does it do to the bone marrow?

Back 286

- it causes necrosis of the intestinal crypt cells and causes a non-hemorrhagic enteritis
- destroys bone marrow, causing a panleukopenia

Front 287

nematode parasite of the large intestine of dogs that causes hemorrhagic enteritis

Back 287

hookworms

Front 288

what are three bacteria that infect the large intestine of neonates and cause hemorrhagic enteritis (other than E. coli)

Back 288

1. Clostridium perfringens type A - large animals
2. Clostridium perfringens type C - large animals
3. Clostridium difficile - foals

Front 289

name eight bacterial genera that are involved in severe lower GI infections and the diseases they cause

Back 289

1. Brachyspira - swine dysentery
2. Clostridium - neonatal enteritis, Colitis X, ulcerative enteritis of birds, enterotoxemia of sheep,
3. Escherichia (E. coli) - enteritis of all kinds
4. Fusobacterium - ruminal ulcers
5. Mycobacterium - Johne's, proliferative enteritis of birds
6. Salmonella - hemorrhagic enteritis
7. Yersinia - fibrinonecrotic colitis in primates and rodents
8. Lawsonia - proliferative enteritis in pigs

Front 290

what is hemorrhagic bowel syndrome?

Back 290

thought to be caused by Clostridium perfringens type A, a disease of adult dairy cows which produces hemorrhage and blood clots in the duodenum and jejunum, often leading to fatality.

Front 291

thought to be caused by Clostridium perfringens type A, a disease of adult dairy cows which produces hemorrhage and blood clots in the duodenum and jejunum, often leading to fatality.

Back 291

Hemorrhagic bowel syndrome

Front 292

an idiopathic hemorrhagic disease in the duodenum of horses

Back 292

proximal enteritis

Front 293

what common class of protozoan causes hemorrhagic enteritis in a variety of animals?

Back 293

coccidia

Front 294

bacterial infection of pigs marked by thickening of the intestinal mucosa with necrosis and hemorrhage.

Back 294

Lawsonia intracellularis

Front 295

Lawsonia intracellularis
- species affected
- disease
- lesions and gross appearance

Back 295

- pigs, hamsters (also horses and dogs)
- proliferative enteritis
- marked thickening of the SI mucosa with necrosis and hemorrhage
- mucosa has a corrugated appearance and may also have a fibrinonecrotic pseudomembrane

Front 296

an idiopathic disease in horses where the SI mucosa is infiltrated with macrophages

Back 296

granulomatous enteritis

Front 297

bacterial infection of birds and occasionally mammals that results in diffuse thickening of the mucosa caused by granulomatous inflammation with acid-fast bacteria and macrophages

Back 297

Mycobacterium avium

Front 298

what does chronic coccidiosis look like in sheep?

Back 298

focal 1-2 mm, raised plaques or nodules in the intestines

Front 299

what are two non-infectious, non-neoplastic pathologic conditions of muscle of the GI tract?

Back 299

1. idiopathic muscular hypertrophy of the distal ileum in horses
2. hypertrophy of the tunica muscularis externa and tunica muscularis mucosa secondary to chronic obstruction

Front 300

an incidental finding in horses in which there are single or multiple red to brown plaques on the serosa, usually near the ileum.

Back 300

Hemomelasma ilei

Front 301

what is hemomelasma ilei

Back 301

an incidental finding in horses in which there are single or multiple red to brown plaques on the serosa, usually near the ileum.

Front 302

a rickettsia infection of horses transmitted by insect vectors. The colon is filled with watery content and the mucosa has patchy congestion with no ulcers, fibrin or hemorrhage.

Back 302

Potomac horse fever

Front 303

Potomac horse fever

Back 303

a rickettsia infection of horses transmitted by insect vectors. The colon is filled with watery content and the mucosa has patchy congestion with no ulcers, fibrin or hemorrhage.

Front 304

accumulation of clear, yellow fluid in the abdomen

Back 304

ascites

Front 305

ascites

Back 305

accumulation of clear, yellow fluid in the abdomen

Front 306

extensive fibrosis in the liver producing portal hypertension and ascites

Back 306

chronic liver disease

Front 307

how does chronic liver disease manifest in the abdomen?

Back 307

extensive fibrosis in the liver producing portal hypertension and ascites

Front 308

an E. coli infection of pigs, where the bacteria produces a toxin which causes edema of the subcutis, stomach, and mesentery

Back 308

edema disease of swine

Front 309

edema disease of swine
- causative agent
- where is the edema?

Back 309

an E. coli infection of pigs, where the bacteria produces a toxin which causes edema of the subcutis, stomach, and mesentery

Front 310

blood in the abdomen

Back 310

hemoperitoneum

Front 311

in cattle, when a metallic object perforates the reticulum, diaphragm, and pericardial sac

Back 311

traumatic reticulopericarditis

Front 312

what inflammatory process is associated with traumatic reticulopericarditis

Back 312

fibrinous pericarditis

Front 313

in which two animals is ruptured urinary bladder most common (pathogenesis)

Back 313

castrated male cats and steer secondary to blockage with mineral deposits

Front 314

what inflammatory process does urine in the abdomen produce?

Back 314

fibrinous peritonitis

Front 315

a corona virus infection of cats causing high-protein fluid to form in the body cavities along with fibrin. Small, white plaques on the mesentery and granulomas may be seen in various organs

Back 315

feline infectious peritonitis

Front 316

feline infectious peritonitis

Back 316

a corona virus infection of cats causing high-protein fluid to form in the body cavities along with fibrin. Small, white plaques on the mesentery and granulomas may be seen in various organs

Front 317

how does fat necrosis appear in the GI tract?

Back 317

firm, chalky, yellow to brown plaques or nodules

Front 318

what are two common non-infectious causes of fat necrosis in the cat?

Back 318

Vitamin E deficiency, high dietary polyunsaturated fats

Front 319

necrosis of the mesenteric fat around the pancreas of the dog or cat is probably what?

Back 319

pancreatitis

Front 320

in which animals does idiopathic fat necrosis occur?

Back 320

Jersey and Guernsey cows

Front 321

what plant causes fat necrosis in cattle

Back 321

Fescue toxicosis

Front 322

how do lipomas often appear in the horse?

Back 322

in the mesentery, they often hang by a fibrous stalk which causes occlusion of blood supply to the lipoma. The fat becomes necrotic and mineralized. "strangulated lipoma"

Front 323

how does chronic peritonitis appear?

Back 323

fibrous tags on the peritoneum, which makes the peritoneum appear shaggy. Adhesions of the intestine.

Front 324

what species and where in the body is mesothelioma most commonly found? What do they look like?

Back 324

- congenital in calves, or in the adult dog
- abdomen, thorax, or pericardial space
- multiple white nodules and plaques in the abdomen

Front 325

in the cat, an infectious disease characterized by small white plaques on the mesentery and/or nodules in the abdominal region

Back 325

feline infectious peritonitis

Front 326

in which breed of dogs is hypoplasia of the pancreas most common?

Back 326

German Shepherds

Front 327

a dog with a voracious appetite and large, voluminous, foul-smelling feces may have what?

Back 327

hypoplasia of the pancreas

Front 328

necrosis, hemorrhage, and edema of the pancreas, often with fibrin deposition

Back 328

acute pancreatitis

Front 329

how does chronic pancreatitis appear in the dog?

Back 329

pale, tan, firm, and nodular

Front 330

what are the two most common neoplasms of the pancreas?

Back 330

adenoma or adenocarcinoma

Front 331

how does hyperplasia of exocrine pancreatic tissue appear?

Back 331

(incidental), 1-3mm tan to white nodules in the pancreas

Front 332

what produces a pale tan or brown color change in the liver

Back 332

it can be modest amounts of fat or glycogen within the liver cells

Front 333

comment on the pathology of a tan or brown color change in the liver that is diffuse versus focal.

Back 333

- diffuse change is pathologic (nutritional or metabolic disease such as diabetes or Cushings)
- focal change is physiologic and not pathologic

Front 334

what causes a yellow color change in the liver?

Back 334

fat

Front 335

what are two patterns of fat change in the liver?

Back 335

diffuse or lobular

Front 336

why would a liver have green color change

Back 336

excess bile accumulation, resulting in icterus. The liver appears yellow-green or olive green

Front 337

why would a liver have a red or red-brown color change?

Back 337

congestion. This is seen in most livers at necropsy

Front 338

a disease process that affects a specific lobule of the liver will have what histologic pattern?

Back 338

lobular/reticular

Front 339

what are five disease processes that cause a lobular/reticular pattern in the liver

Back 339

1. passive congestion
2. anemia
3. lipidosis
4. hepatotoxin
5. cholangitis

Front 340

what is the most common cause of a lobular pattern of liver change?

Back 340

passive congestion

Front 341

what is the most common cause of passive congestion of the liver?

Back 341

heart failure

Front 342

why does anemia cause a lobular pattern in the liver?

Back 342

it is due to hypoxia to the centrilobular cells

Front 343

why does lipid accumulation cause a lobular pattern in the liver?

Back 343

accumulation of lipid in the centrilobular area

Front 344

what is cholangitis?

Back 344

an uncommon bacterial infection of the liver bile ducts, causing a lobular pattern

Front 345

a pattern of liver change similar to the lobular pattern, but more severe, with larger lesions

Back 345

mosaic pattern

Front 346

what is a general cause of a mosaic pattern in the liver?

Back 346

massive necrosis

Front 347

what is a major cause of massive necrosis in the liver of the
- pig?
- dog?

Back 347

- pig: Vitamin E/selenium deficiency
- dog: halothane, anticonvulsants, and other drugs/toxins

Front 348

what is the most common change associated with damage to the liver?

Back 348

fatty change

Front 349

what are two basic causes of focal or multifocal change to the liver?

Back 349

1. infectious disease
2. neoplasia

Front 350

what are four neoplasias of the liver?

Back 350

1. hepatocellular carcinoma
2. biliary adenoma and carcinoma
3. metastatic carcinomas and sarcomas
4. nodular hyperplasia

Front 351

a rare tumor of the liver, mostly in the dog, usually single masses, but can be multilobulated, which present as focal areas of brown, red hemorrhage, and yellow (fat)

Back 351

hepatocellular carcinoma

Front 352

hepatocellular carcinoma
- what is it?
- species affected
- gross lesions

Back 352

a rare tumor of the liver, mostly in the dog, usually single masses, but can be multilobulated, which present as focal areas of brown, red hemorrhage, and yellow (fat)

Front 353

a single, discrete nodule in the liver that often cystic and contains green or clear fluid, occurring in the cat. In the dog it is seen rarely as multiple firm, white nodules with depressed centers

Back 353

biliary adenoma/carcinoma

Front 354

describe biliary adenoma/carcinoma in the cat and dog

Back 354

a single, discrete nodule in the liver that often cystic and contains green or clear fluid, occurring in the cat. In the dog it is seen rarely as multiple firm, white nodules with depressed centers

Front 355

what does a primary hemangiosarcoma of the liver look like?

Back 355

multiple red nodules and blood-filled cysts

Front 356

how do metastatic carcinomas or sarcomas in the liver typically appear?

Back 356

multifocal tumors in the liver that appear as multiple, firm white nodules

Front 357

an incidental finding in the liver of an aged dog, a solitary discrete nodule that is soft and tan due to fat accumulation. Some consider these to be hepatocellular carcinoma.

Back 357

nodular hyperplasia of the liver

Front 358

what is nodular hyperplasia of the liver?

Back 358

an incidental finding in the liver of an aged dog, a solitary discrete nodule that is soft and tan due to fat accumulation. Some consider these to be hepatocellular carcinoma.

Front 359

how much liver can be removed for complete regeneration?

Back 359

up to two-thirds

Front 360

what microanatomical aspect of the liver is necessary for regeneration

Back 360

in intact architectural framework and basement membrane is necessary

Front 361

what are two major rule-outs for a lobular pattern in the liver?

Back 361

1. toxins
2. hypoxia

Front 362

what is the term applied to regenerating hepatocytes?

Back 362

regenerative nodules

Front 363

what is the usual lesion seen in chronic liver disease? What patterns of this lesion are seen?

Back 363

fibrosis: lobular (portal or central) or multifocal

Front 364

inflammation of the biliary system

Back 364

cholangitis

Front 365

an important, common liver disease in dogs that is of unknown cause. The liver is misshapen and has many nodules (cirrhosis)

Back 365

chronic hepatitis

Front 366

nodular regeneration of the liver with fibrosis

Back 366

cirrhosis

Front 367

what is cirrhosis of the liver?

Back 367

nodular regeneration of the liver with fibrosis

Front 368

why are patches of red seen in a mosaic pattern in the liver? Why is there yellow?

Back 368

when blood enters the liver, blood tends to dump into the necrotic regions, making it red. The yellow is from lipid accumulation in the necrotic tissue

Front 369

what causes a "nutmeg liver"

Back 369

massive necrosis. It is like a mosaic liver, but in a microscopic lobular pattern.

Front 370

the healing phase of massive necrosis of the liver is called what? What does it look like?

Back 370

post necrotic scarring. The necrotic lobules collapse, forming bands of fibrous tissue

Front 371

what is the pathogenesis of liver injury secondary to chronic heart failure?

Back 371

chronic passive congestion and fibrosis in the centrilobular areas. The liver retains its shape pretty well, but is congested with a nodular pattern.

Front 372

a rare disease of the liver caused by a bacterial infection in the biliary tract. The liver is firm and has a lobular pattern.

Back 372

chronic cholangitis

Front 373

describe chronic cholangitis

Back 373

a rare disease of the liver caused by a bacterial infection in the biliary tract. The liver is firm and has a lobular pattern.

Front 374

why are lesions so commonly seen in the centrilobular areas of the liver when exposed to toxins?

Back 374

because these cells try to detoxify the substance, damaging themselves in the process

Front 375

what type of lesions are produced by bacteria in the liver

Back 375

multifocal

Front 376

what lesions to the liver are commonly observed with portosystemic shunts?

Back 376

since the portal vein is the main blood supply to the liver, shunting of blood leads to atrophy of the liver cells and a small liver

Front 377

what two types of processes most commonly cause multifocal lesions in the liver?

Back 377

bacterial infection (not toxins, etc.) and neoplasia

Front 378

why can acquired portosystemic shunts develop? Pathogenesis? What are lesions outside the liver commonly seen?

Back 378

- chronic liver disease such as cirrhosis
- scarring in the liver ↑pressure in the portal veins, causing pressure buildup in the portal system
- tortuous, distended veins often appear in the mesentery

Front 379

comment on hepatocellular carcinoma in the woodchuck versus other species

Back 379

associated with viral infection

Front 380

distended, firm bile ducts:
- common etiology and species affected
- lesions

Back 380

- associated with liver flukes in sheep and cattle
- they are visible on the liver surface as white, thick, tortuous channels are often raised above the liver surface.

Front 381

white, thick, tortuous channels raised above the liver surface in a sheep or cow is indicative of what type of infection? What is this lesion?

Back 381

- liver flukes
- distended, firm bile ducts

Front 382

what is the most common cause of hemorrhage of the gall bladder?

Back 382

bleeding disorders such as DIC or anticoagulant toxicosis

Front 383

a disease of the gall bladder that can occur by Salmonella infection in cattle

Back 383

fibrinous cholecystitis

Front 384

what causes fibrinous cholecystitis in cattle?

Back 384

Salmonella infection

Front 385

what is the usual cause of thick, viscous, opaque bile?

Back 385

anorexia

Front 386

how does nodular hyperplasia of the dog liver look?

Back 386

well-delineated, single or multiple discrete masses.

Front 387

an uncommon, incidental finding of unknown cause in dogs, where the mucosa of the gall bladder contains numerous small cysts, or larger, papillary, or nodular growths.

Back 387

cystic hyperplasia

Front 388

a collection of mucus in the gall bladder, forming a solid gel that obstructs the gall bladder and can lead to rupture.

Back 388

gall bladder mucocele

Front 389

what lesions and diseases are seen with a gall bladder mucocele?

Back 389

- cystic hyperplasia
- icterus
- gall bladder rupture

Front 390

aggregates of neutrophils and sometimes eosinophils in the epidermis

Back 390

pustules

Front 391

inflammation of the skin that is predominantly neutrophils

Back 391

pyoderma

Front 392

a dried-up accumulation of keratin, inflammatory cells, serum, and bacteria on the skin

Back 392

crust (a scab)

Front 393

what are two requirements for a liver to be called cirrhotic?

Back 393

nodules and scarring

Front 394

scarring of the liver without nodules is called what?

Back 394

fibrosis

Front 395

what is the a major cause of pustular dermatitis?

Back 395

bacterial or fungal infection

Front 396

inflammation of the hair follicle caused by infection with bacteria, fungi, or Demodex mites

Back 396

folliculitis

Front 397

an autoimmune pustular dermatitis caused by an autoantibody against keratinocytes

Back 397

pemphigus foliaceus

Front 398

detached keratinocytes that are found histologically floating in a pustule is called what? What disease is this indicative of?

Back 398

- acanthocytes or acantholytic cells
- diagnostic histologic feature of pemphigus foliaceus

Front 399

fluid-filled cavities within or beneath the epidermis less than 5 mm in diameter

Back 399

vesicle

Front 400

a vesicle greater than 5 mm in diameter

Back 400

bulla

Front 401

edema between the keratinocytes of the skin

Back 401

spongiosis

Front 402

edema within the keratinocytes of the skin

Back 402

intracellular edema

Front 403

what is the usual resolution of a bulla on the skin?

Back 403

rupture and crust formation

Front 404

why do vesicles form in spongiosis or intracellular edema of the skin?

Back 404

from the loss or displacement of keratinocytes

Front 405

intracellular edema within the basal epidermal cells

Back 405

hydropic degeneration

Front 406

what lesion is associated with hydropic degeneration in the skin?

Back 406

intracellular edema within the basal epidermal cells

Front 407

what are three etiologies of hydropic degeneration of the skin?

Back 407

1. lupus
2. dermatomyositis
3. drug reactions

Front 408

intracellular edema within the superficial keratinocytes of the epidermis

Back 408

ballooning degeneration

Front 409

what causes ballooning degeneration of the skin

Back 409

viral infection, such as pox virus

Front 410

what is the histopathological difference between hydropic degeneration and ballooning degeneration of the skin?

Back 410

- hydropic degeneration is intracellular edema within the basal epidermal cells
- ballooning degeneration is intracellular degeneration within the superficial keratinocytes of the epidermis.

Front 411

what are two autoimmune diseases that cause vesicular dermatitis?

Back 411

1. pemphigus vulgaris
2. bullous pemphigoid

Front 412

describe the histopathological appearance of pemphigus vulgaris.

Back 412

suprabasilar vesicle containing acantholytic cells

Front 413

describe the histopathological appearance of bullous pemphigoid.

Back 413

it is a subepidermal vesicle

Front 414

what are the causes of pemphigus vulgaris and bullous pemphigoid?

Back 414

an antibody directed against the keratinocyte (pemphigus vulgaris) or the basement membrane (bullous pemphigoid)

Front 415

a group of inherited congenital diseases producing bullae and vesicles at the dermal-epidermal junction that progress to ulcers.

Back 415

epidermolysis bullosa

Front 416

what is epidermolysis bullosa?

Back 416

a group of inherited congenital diseases producing bulla and vesicles at the dermal-epidermal junction that progress to ulcers.

Front 417

what is the usual end-stage of necrosis of the skin?

Back 417

ulceration

Front 418

a flat, discolored area of the skin, usually less than 1 cm in diameter that can lead to crust formation and ulceration

Back 418

macule

Front 419

a slightly raised area within the skin which is usually red

Back 419

papule

Front 420

what are six etiologies of necrotizing dermatitis?

Back 420

1. erythema multiforme
2. toxic epidermal necrolysis
3. burns
4. photosensitization
5. systemic bacterial infections
6. foot rot

Front 421

necrosis of single keratinocytes throughout the epidermis

Back 421

erythema multiforme

Front 422

a severe form of erythema multiforme characterized by full-thickness epidermal necrosis

Back 422

toxic epidermal necrolysis

Front 423

what is the main cause of erythema multiforme and toxic epidermal necrolysis?

Back 423

adverse drug reaction in association with systemic inflammation and neoplasia

Front 424

what two factors, extrinsic to the skin, can predispose an animal to photosensitization?

Back 424

1. a photodynamic agent in the feed
2. secondary to chronic liver disease

Front 425

how can systemic bacterial infection lead to necrosis of the skin?

Back 425

bacteria localize, producing a vasculitis and thrombosis that leads to necrosis

Front 426

a necrotizing dermatitis of the interdigital skin of cattle in sheep caused by a Fusobacterium and/or a mixed infection

Back 426

foot rot

Front 427

what is the most common cause of exudative dermatitis?

Back 427

allergic skin disease

Front 428

allergic skin disease caused by inhalation of an allergen or food allergy

Back 428

atopy

Front 429

for allergic skin disease, comment on the species differences in the role of eosinophils in dogs, cats, and horses

Back 429

eosinophils play a role in cats and horses, but not dogs.

Front 430

a group of three histologically different diseases of the skin caused by hypersensitivity or allergy, and may produce nodules, papules, or ulcers.

Back 430

eosinophilic granuloma complex

Front 431

describe eosinophilic granuloma complex

Back 431

a group of three histologically different diseases of the skin caused by hypersensitivity or allergy, and may produce nodules, papules, or ulcers.

Front 432

inflammation of the epidermis

Back 432

dermatitis (not "epidermitis")

Front 433

inflammation of the skin

Back 433

dermatitis

Front 434

an allergic skin disease caused by contact of the skin with an allergic substance

Back 434

allergic contact dermatitis

Front 435

allergic contact dermatitis:
- what usually causes this condition?
- describe the lesions

Back 435

- chemicals and plastics
- lesions may very from papules to crusts

Front 436

direct contact of the skin with irritating substances

Back 436

irritant contact dermatitis

Front 437

irritant contact dermatitis:
- what can cause this condition?
- describe the lesions

Back 437

- drugs, soaps, acids, detergents, and others
- depending on the severity of the irritant: erythematous papules or ulcers and crusts of exudative dermatitis

Front 438

what is the scientific name for a "hot spot?"

Back 438

pyotraumatic dermatitis

Front 439

a severe exudative dermatitis of the dog caused by self-inflicted trauma of biting and scratching because of the pruritis and pain from allergic skin disease

Back 439

pyotraumatic dermatitis ("hot spots")

Front 440

where on the body does contact dermatitis usually occur?

Back 440

places with sparse or no hair

Front 441

excess keratin on the surface of the skin and grossly produces flakes or scales on the skin.

Back 441

hyperkeratosis/seborrhea

Front 442

what are the two histologic patterns of hyperkeratosis?

Back 442

1. orthokeratotic (called "hyperkeratosis")
2. parakeratotic (called "parakeratosis")

Front 443

what is the major histological difference between hyperkeratosis and parakeratosis?

Back 443

in hyperkeratosis, the cells lack nuclei; in parakeratosis the cells have nuclei

Front 444

what are two causes of seborrhea in the dog?

Back 444

1. an inherited defect in keratinization
2. occurring secondary to primary skin diseases such as allergy, parasites, infection, and endocrine diseases

Front 445

what parasites commonly cause perivascular dermatitis with hyperkeratosis?

Back 445

mites such as Sacroptes and Choioptes

Front 446

a group of disorders of cornification characterized by hyperkeratosis and the accumulation of scales that look like fish scales. It is a congenital inherited disease

Back 446

ichthyosis

Front 447

what is ichthyosis?

Back 447

a group of disorders of cornification characterized by hyperkeratosis and the accumulation of scales that looks like fish scales. It is a congenital inherited disease

Front 448

a disease of small animals causing parakeratosis and associated with chronic liver disease. Associated with defective glucose and amino acid metabolism

Back 448

superficial necrolytic dermatitis

Front 449

what is superficial necrolytic dermatitis?

Back 449

a disease of small animals causing parakeratosis and associated with chronic liver disease. Associated with defective glucose and amino acid metabolism

Front 450

hyperplasia of the epidermis

Back 450

acanthosis

Front 451

a hyperplastic condition of the skin that may appear thickened grossly and have a leathery texture

Back 451

lichenification

Front 452

increased melanin pigment in the epidermis that makes the skin look dark or black

Back 452

hyperpigmentation

Front 453

what is the most common cause of hyperpigmentation of the skin?

Back 453

chronic hyperplastic dermatitis

Front 454

hypopigmentation due to a generalized absence of melanocytes

Back 454

piebaldism

Front 455

hypopigmentation due to a localized absence of melanocytes

Back 455

vitiligo

Front 456

hypopigmentation of the skin due to lack of melanin production by melanocytes

Back 456

albinism

Front 457

what are three general etiologies of skin hypopigmentation?

Back 457

1. absence of melanocytes - piebaldism (generalized) and vitiligo (localized)
2. albinism (lack of melanin production)
3. acquired - inflammation, trauma, irritants, nutritional

Front 458

what is the general pathogenesis of inflammation of the skin?

Back 458

All inflammation must come from the blood vessels. It usually starts as perivascular dermatitis and may spread to become diffuse or nodular.

Front 459

parasitic infection of the skin
- which inflammatory cells predominate?
- what lesions are present?

Back 459

- eosinophils
- maculopapular eruptions, crusts, and a perivascular dermatitis

Front 460

what are two major rule-outs for eosinophils in skin inflammation?

Back 460

1. parasite infection (e.g. mites, fleas, flies)
2. allergic skin disease

Front 461

inflammation of the superficial dermis at the dermal/epidermal junction, which obscures the distinction between the dermis and epidermis

Back 461

interface dermatitis

Front 462

what is interface dermatitis?

Back 462

inflammation of the superficial dermis at the dermal/epidermal junction, which obscures the distinction between the dermis and epidermis

Front 463

a dense band of inflammation on the superficial dermis which is distinct and sharply demarcated from the adjacent tissue

Back 463

lichenoid dermatitis

Front 464

what is the difference between interface dermatitis and lichenoid dermatis?

Back 464

- interface dermatitis: dermal/epidermal junction is not well-defined
- lichenoid dermatitis: dermal/epidermal junction is sharply demarcated

Front 465

what is lichenoid dermatitis?

Back 465

a dense band of inflammation on the superficial dermis which is distinct and sharply demarcated from the adjacent tissue

Front 466

firm swellings in the dermis and/or subcutis and palpate as a mass

Back 466

nodules

Front 467

what are five causes of nodular dermatitis?

Back 467

1. infection
2. sterile granulomatous/pyogranulomatous nodular dermatitis (dogs only)
3. furunculosis
4. panniculitis
5. neoplasia

Front 468

infection of the dermis usually produces what type of lesion?

Back 468

nodular dermatitis

Front 469

in the dog, a non-infectious inflammation of the dermis, centered on the adnexa, which produces a nodular dermatitis

Back 469

sterile granulomatous/pyogranulomatous nodular dermatitis

Front 470

a nodular dermatitis produced by the rupture of hair follicles

Back 470

furunculosis

Front 471

what is furunculosis? pathogenesis?

Back 471

- a nodular dermatitis caused by rupture of hair follicles
- occurring secondary to folliculitis or trauma (licking, biting), a release of hair and keratin into the dermis, which elicits a severe inflammation.

Front 472

inflammation of the subcutis in cats and dogs that may or may not involve the dermis or epidermis. produces a nodular dermatitis.

Back 472

panniculitis

Front 473

what is panniculitis?

Back 473

inflammation of the subcutis in cats and dogs that may or may not involve the dermis or epidermis. produces a nodular dermatitis.

Front 474

what are four etiologies for panniculitis?

Back 474

- secondary to dermatitis
- physical injury or infection
- vitamin E deficiency in the cat
- idiopathic

Front 475

loss of hair

Back 475

alopecia

Front 476

what is the most important cause of primary alopecia?

Back 476

endocrine skin disease

Front 477

what is the usual pattern of alopecia associated with endocrine skin disease?

Back 477

bilaterally symmetrical alopecia over the perineum, back, and flanks.

Front 478

what is the most common endocrine disorder that causes endocrine skin disease? what are two other less-common causes?

Back 478

- most common: hypothyroidism
- also: hyperestrogenism and hyperadrenocorticism

Front 479

what is the main lesion seen with endocrine skin disease?

Back 479

alopecia due to hair follicle atrophy

Front 480

a group of inherited diseases characterized by alopecia and an absence of hair follicles

Back 480

hypotrichosis

Front 481

a group of hereditary diseases in which collagen is defective. The skin is hyper-extensible, loose, and tears easily

Back 481

collagen dysplasia (dermatosparaxis, cutaneous asthenia)

Front 482

abnormal development of hair follicles

Back 482

follicular dysplasia

Front 483

where on/in the body does cutaneous squamous cell neoplasia occur in the
- dog?
- horse?
- cow?
- cat?

Back 483

- dog: skin and oral cavity
- horse: penis, eye, stomach
- cow: eye
- cat: nose, pinna

Front 484

where does melanoma occur in the following animals (comment on malignancy)?
- dogs
- horses

Back 484

- dogs: skin (usually benign); oral cavity (usually malignant)
- perineum of old gray horses (benign, but multiple masses present)

Front 485

cutaneous warts
- scientific name
- cause
- species most commonly affected
- age factor

Back 485

- papilloma
- epithelial tumor caused by a papilloma virus
- most often in cattle, but also horse and dog
- affects young animals and usually spontaneously regresses

Front 486

a rare benign tumor of the skin of the dog with a predisposition in the Norwegian Elkhound

Back 486

Intracutaneous cornifying epithelioma (keratoacanthoma)

Front 487

what breed of dog is most predisposed to Intracutaneous cornifying epithelioma (keratoacanthoma)?

Back 487

Norwegian Elkhound

Front 488

what is the most primitive of the skin adnexal tumors? in which species are these most common?

Back 488

- basal cell tumor
- dogs and cats

Front 489

a common benign adnexal tumor of the dog arising from the hair follicle that makes hair follicle and hair

Back 489

trichoepithelioma

Front 490

what is a trichoepithelioma?

Back 490

a common benign adnexal tumor of the dog arising from the hair follicle that makes hair follicle and hair

Front 491

a rare benign tumor of the dog arising from the hair matrix, where only hair is made.

Back 491

pilomatricoma

Front 492

what is a pilomatricoma

Back 492

a rare benign tumor of the dog arising from the hair matrix, where only hair is made.

Front 493

what are three general tumors of the glands of the skin?

Back 493

1. sebaceous gland tumors
2. apocrine gland tumors
3. perianal gland tumors

Front 494

what are the three most common locations of apocrine gland tumors in the dog and cat?

Back 494

1. sweat glands
2. ceruminous glands of the external ear
3. apocrine glands of the anal sac

Front 495

which tumors of the glands of the skin in the dog have a predisposition to
- females?
- males?

Back 495

- female: apocrine gland tumor of the anal sac
- male: perianal gland tumors

Front 496

what often occurs secondarily to apocrine gland tumors of the anal sac?

Back 496

hypercalcemia

Front 497

a very common benign tumor of dogs less than 2 years of age that arises from the Langerhans (dendritic) cells of the epidermis

Back 497

histiocytoma

Front 498

histiocytoma in the epidermis
- species
- age
- what cells are affected?
- malignancy

Back 498

- dog
- < 2 years of age
- Langerhans (dendritic) cells
- benign

Front 499

mast cell tumors
- species
- malignancy

Back 499

- most common in dog, but also seen in cat and horse
- can be benign or malignant

Front 500

a rare benign tumor of the dog and cat arising from fibroblasts

Back 500

fibroma

Front 501

what type of tumor can occur in the skin of cats secondarily to vaccination?

Back 501

fibrosarcoma

Front 502

malignant tumor of fibroblasts

Back 502

fibrosarcoma

Front 503

a fibroblast tumor of the horse which is benign and does not metastasize, but has a high rate of local recurrence

Back 503

sarcoid

Front 504

what is a sarcoid?

Back 504

a fibroblast tumor of the horse which is benign and does not metastasize, but has a high rate of local recurrence

Front 505

a very common benign tumor of the dog that arises from fat or adipocytes

Back 505

lipoma

Front 506

plasma cell tumor
- species
- where in/on the body does it occur?

Back 506

- dog
- skin and oral cavity

Front 507

tumor arising from vascular endothelium

Back 507

hemangioma

Front 508

a common tumor of unknown cellular origin that occurs in the dermis and subcutis of dogs.

Back 508

hemangiopericytoma