Exam 1 Flashcards
Where in the GI tract are Peyer’s patches located?
Ileum
Function of M cells in GALT?
Uptake of antigens, therefore can be exploited for pathogen entry if GALT or intestinal epithelium is damaged
Defense mechanisms of the oral cavity (4)
- Taste buds - reject toxic materials
- Indigenous micro flora - compete for attachment site
- Saliva - flushing, protective coating, antimicrobial, anti foaming
- Rapid healing ability
Cleft palate = ?
Palatoschisis
Palatoschisis = ?
Cleft palate
Cleft lip = ?
Cheiloschisis
Cheiloschisis = ?
Cleft lip
Prognathia = ?
Underbite, mandible extends past maxilla
Brachygnathia = ?
Overbite, maxilla extends past mandible
Layers of teeth outer to inner?
Outer = enamel
Dentin
Cementum
Pulp
Anondontia = ?
No teeth
Oligodontia = ?
Fewer than normal number of teeth
Polydontia = ?
Excessive number of teeth
Pseudopolydontia = ?
Retention of deciduous teeth
Heterotrophic polydontia = ?
Extra teeth, or teeth outside the dental arcade (“ear tooth”)
Dentigerous cyst = ?
Cyst containing malformed tooth
Malocclusion = ?. Common in what species?
Abnormal jaw configuration or rarely abnormal tooth eruption patterns. Rabbits and rodents because teeth are continuously erupting, can overgrow if not receiving enough roughage in diet.
Enamel hypoplasia = ?
Enamel fails to develop to normal size
During tooth development, what factors can result in ameloblast damage that causes defects in enamel or abnormal enamel?
CDV, fluoride toxicosis, malnutrition, Vit A deficiency
What factors can cause tooth discoloration?
Tetracycline antibiotics, congenital porphyria
What is tartar/calculus composed of?
Sloughed epithelial cells, inflammatory cells, food, bacteria. These form calcium salts
What does tartar predispose an animal to?
Gingivitis and periodontitis
Microanatomical changes seen with periodontal disease?
Gingival crest recession, inflammatory infiltration, subgingival calculus, resorption of bone, loss of epithelial attachment, edema, degeneration of peri dental membrane, deepening of pocket
Dental attrition = ?
Wearing down/degeneration of teeth so that there is unevenness
What is the difference between a Ranula and a Mucocele?
Ranula = cystic distention of a salivary duct in the floor of the mouth. The lining epithelium is intact!
Mucocele = accumulation of salivary secretion in single non-epithelial lined cyst adjacent to ducts.
Ranula = ? Is lining epithelium intact?
Cystic distention of a salivary duct in the floor of the mouth, lining epithelium intact.
Salivary mucocele = ? Is lining epithelium intact?
Accumulation of salivary secretion in single non-epithelial lined cyst adjacent to ducts. No
Stomatitis = ?
Inflammation of oral mucosa
Cheilitis = ?
Ki-litis. Inflammation of the lips
Glossitis =
Inflammation of tongue
Gingivitis =
Inflammation of gingiva
5 morphologic types of stomatitis?
- Vesicles
- Deep necrosis
- Erosions
- Ulcers
- Papules
Erosions can develop from …
Vesicles
Vesicles in the oral mucosa can develop into ..
Erosions
Erosions vs. ulcers?
E - BM intact, can repair
U - BM not intact
How do vesicles form? What happens if they rupture above the basement membrane?
Epithelial cell infection with ballooning degeneration, cell lysis - intraepithelial vesicles - clear watery fluid.
If ruptures above BM, erosion occurs. Erosion can heal completely
Examples of epitheliotropic viruses (which are vesicular stomatitides)?
Foot and mouth disease, vesicular stomatitis, swine vesicular disease, feline calico virus, vesicular exanthema of swine, herpes B stomatitis
What is the only vesicular stomatitides that affects horses?
Rhabdovirus
Macroscopic lesions of vesicular stomatitis in horses?
Would be rhabdovirus. Vesicles and erosions in the mucous membranes of mouth or on skin of the teats and feet. Lesions resemble foot and mouth disease.
Examples of viral erosive/ulcerative stomatitis? What cells do these viruses cause apoptosis/necrosis of?
BVD, malignant catarrhal fever (herpesvirus), rinderpest, adenovirus in deer, infectious bovine rhinotracheitis, feline calicivirus and herpesvirus, orbivirus
Epithelial cells!
Uremic stomatitis is due to what toxin’s effect on epithelial cells or capillaries? What condition could this be associated with?
Urea - causes fibrinoid necrosis and ischemia/infarction.
Renal disease - increased BUN - endothelial necrosis with thrombosis and infarction.
Examples of viral papular “proliferative” stomatitis?
Bovine papular stomatitis (parapoxvirus)
Ovine contagious ecthyma = Orf
Papule = ? What type of cells become swollen and proliferating?
Small, solid raised epithelial dome.
Keratinocytes
Necrotizing “deep” stomatitis is often caused by what?
Trauma - then opportunistic infections
Examples of necrotizing “deep” stomatitis?
- Oral necrobacillosis
- Actinobacillosis (wooden tongue) - actinobacillus lignieresi
- Actinomycetes (lumpy jaw)
What agent causes wooden tongue on cows? What type of stomatitis is this?
Actinobacillus lignieresi. Necrotizing/deep.
T/F there are many afferent lymphatic vessels to the tonsils
False - there are none
By what means can the tonsils become infected?
Tonsils have no afferent lymphatic vessels, so are affected either by hematogenous spread or primary/direct spread.
Which of the following diseases is NOT expected to cause vesicular oral lesions?
A. Foot and mouth disease
B. Blue tongue
C. Vesicular exanthema of swine
D. Contagious ecthyma
D - contagious ecthyma is a viral popular “proliferative” stomatitis, so would cause papule formation
Which of the following oral neoplasms is generally self-limiting and can regress over time?
A. Melanoma
B. Maxillofacial Fibrosarcoma
C. Papillomatosis
D. Fibrous
E. Squamous cell carcinoma
C
What is the most common oral malignancy in cats?
Squamous cell carcinoma
What is the most common oral malignancy in dogs?
Melanoma
Examples of oral neoplasms?
Peripheral odontogenic fibroma, squamous cell carcinoma, melanoma, Fibrosarcoma, oral papillomas, lymphoma, plasmacytoma
What type of cancer arises from the periodontal ligament in the oral cavity of dogs and cats?
Peripheral odontogenic fibroma
What is a ddx for peripheral odontogenic fibroma in cats and dogs?
Gingival hyperplasia and other neoplasms
Peripheral odontogenic fibroma’s arise from the … ligament
Periodontal
T/F in cats, squamous cell carcinomas are self-limiting and non-invasive.
False - they are locally invasive and often invade adjacent bone and metastasize to mandibular lymph nodes
What do squamous cell carcinoma’s typically look like microscopically?
Like little nests of neoplastic cells with keratin at the middle
What are the two forms of malignant melanoma?
Melanotic - gray/brown/black/blue
Amelanotic - pale to red
T/F metastasis is not common in oral melanomas
False - metastasis occurs in 70-90% of oral melanomas
T/F metastasis is rare in fibrosarcoma’s
True - locally aggressive but Mets rare
T/F oral papillomatosis are usually self-limiting and spontaneously resolve.
True
What is the tumor-like lesion that is locally invasive, usually in the rostral mandible near the canines, is composed of epithelium and CT stroma from gingival epithelium, does not metastasize, and is common in older dogs?
Acanthomatous ameloblastoma
Clinical signs of esophageal dysfunction
Dysphagia, Cachexia, ptyalism (drooling), regurgitation, vomition, aspiration pneumonia
Examples of congenital anomalies of the esophagus?
Segmental aplasias, esophageal-tracheal fistula, esophageal diverticulum, Achalasia (esophageal motility disorders)
Esophageal stenosis =
Decreased diameter of the esophagus
Esophageal obstruction/stenosis can be caused by ?
PRAA, ingestion of solids in cattle, dry feed or poor dentition in horses, chronic obstruction
Congenital megaesophagus is most commonly due to what congenital abnormality?
Persistent right aortic arch
What is a PRAA?
Persistent right aortic arch - vascular ring formed by aorta, pulmonary artery, and ligamentum arteriosum.
Congenital megaesophagus: dilation is usually cranial to heart or stomach? Acquired megaesophagus: dilation is usually cranial to heart or stomach?
Heart, stomach
Potential causes of acquired megaesophagus?
Myasthenia gravis, hypothyroidism, chronic lead toxicosis, peripheral neuropathies, esophagitis, polymyositis
Esophageal foreign bodies can result in mucosal … necrosis
Compression
“Choke” = ?
Traumatic esophagitis and impaction d/t foreign bodies
What chemical do blister beetles produce?
Cantharidin
Cantharidin toxicity affects herbivorous animals when they ingest …, causing erosive/ulcerative esophagitis, rumenitis, gastritis, and duodenitis.
Hay that was contaminated with Cantharidin from blister beetles
Examples of parasitic esophagitis?
Throchomonas (canker) - protozoan, birds
Gongylonemiasis - nematodes, incidental
Spirocerca lupi - carnivores, causes mesenchymal neoplasms (Fibrosarcoma)
Mycotic = ?
Fungal
Agent that causes Mycotic esophagitis?
Candida albicans
Esophageal neoplasia is rare/common. Examples?
Rare
Squamous cell carcinoma, canine leiomyoma, bovine papillomas, canine Fibrosarcoma, lymphoma
A dog presents with numerous cutaneous (face) and oral warts. Which feature is NOT typical of canine papilloma virus infection?
A. The dog is middle aged
B. The warts disappear after a couple of weeks to months spontaneously
C. Intracytoplasmic inclusion bodies in keratinocytes
D. Marked thickening of epithelium
E. Vesicles on the tongue and gingiva
A
The most common neoplasm of the oral cavity of dogs is derived from which of the following?
A. Melanocytes
B. Periodontal ligament
C. Gingiva
D. Lymphocytes
E. Salivary gland
B (peripheral odontogenic fibroma)
What are the most frequent abnormalities of the ruminant forestomach?
Motility problems and ruminants microbial imbalances
Ruminant tympany aka …, is what?
Bloat. Over-distention of the rumen and reticulum with gases of fermentation.
Primary vs. secondary tympany in ruminants?
Primary = legume bloat/dietary bloat/frothy bloat. Usually occurs after switching to new diet
Secondary = physical or functional obstruction or stenosis of esophagus, failure to eructate.
Pathogenesis of primary ruminant tympany (frothy or legume bloat)?
Graze on rapidly growing legumes - leaf cytoplasmic soluble proteins are primary foaming agents - lower pH - optimal for stable foam formation - bacterial overgrowth with slime production - methane and CO2
What is foam composed of (primary ruminant tympany)?
Gas, soluble leaf proteins, and bacterial slime
Is froth present in primary or secondary ruminant tympany?
Primary
Two types of secondary ruminant tympany?
Obstructive - tumor, FB
Functional - oroganophosphate toxicosis, vagus n.
T/F froth is present in secondary ruminant tympany
False
Pathogenesis of ruminal lactic acidosis/grain overload which results in rumenitis?
Heavy ingestion or fermentable CHO’s - overgrowth of gram + and strep. Bovis and lactobacilli - ferment CHO’s to lactic acid - lowers ruminal pH - destroys Protozoa and ruminal micro flora and damages ruminal mucosa
Three complications of lactic acid rumenitis?
Secondary bacterial rumenitis
Liver abscesses/necrosis
Mycotic rumenitis (fungi)
Mycotic rumenitis occurs secondary to ruminal mucosa damage from lactic acidosis or following … administration.
Antibiotic
What nerve, if damaged/inflamed, results in no movements of feed through the forestomach and abomasum in ruminants?
Vagus
What plant has been shown to cause GI squamous cell carcinoma in horses and cats, as well as transitional cell carcinoma of urinary bladder of cattle?
A. Crotalaria
B. Japanese ewe
C. Dieffenbachia
D. Bracken fern
E. Chia pet
D
The foam in frothy bloat is composed of the following except:
A. Bacterial slime
B. Methane
C. Cantharidins
D. Soluble leaf protein
C - this is what blister beetles produce that results in esophagitis/rumenitis/gastritis
What type of gastric biopsy do pathologists prefer? Clinicians?
Path - transmural
Clinical - endoscopic
Endoscopic mucosal vs. transmural biopsies?
Endoscopic - less invasive, better tolerate by patient, more samples can be taken, only mucosal layer observed (not deeper aspects)
Transmural - increased chance of diagnosis, all layers seen, fewer artifacts, more invasive and expensive
Defense mechanisms of the gastric mucosal barrier?
Acid, mucus (contains IgA), epithelium, resident micro flora, pyloric sphincter (prevent SI reflux), vomiting reflex
T/F puppies that have an enlarged belly after overeating have acute gastric dilatation
False - simple dilation
Gastric dilation and rupture in horses occurs after consumption of what?
Fermentable feeds/grains. Typically idiopathic
Displaced abomasum is particularly common in what types of cattle?
Dairy cows that recently gave birth (have lots of empty abdominal space)
Gross appearance of pyloric stenosis in dogs/cats/horses?
Mucosal hypertrophy, muscle wall hypertrophy
Potential causes of peptic ulcers
HCl, trauma, ischemia, NSAIDs
Gastric ulcers that affects swine - which types of pigs mainly affected? Where in the stomach?
Rapidly growing pigs on finely ground grains, pigs that are stressed (have concurrent infection).
Stratified squamous portion of mucosa
Gastric ulcers can develop in dogs due to histamine release from what type of tumor?
Mast cell tumors. Histamine binds to H2 receptors, secrcete HCl, mucosal damage
Gastric ulcers can develop in horses that are on what type of medication?
NSAIDs
What viral vesicular disease affects the mouth and coronary band of horses?
A. Foot and mouth disease
B. Vesicular stomatitis
C. Vesicular axanthema
D. Papular stomatitis
E. Contagious ecthyma
B
Characteristic of chronic ulcers?
Raised pale lip/rim around ulcer
Acute changes observed with gastritis and abomasitis? Chronic?
Acute - mucosal hyperemia, edema, hemorrhage, erosions, ulcer
Chronic - mucosal hypertrophy, ulceration, fibrosis, mineralization
How would you test for Helicobacter spp. causing eosinophilic gastritis?
Urease test
Types of parasites that cause gastritis?
HOT complex - Ostertagia in cattle, Trichostrongyles in sheep.
Gasterophilus in horses
Chronic giant hypertrophic gastropathy occurs in what breeds of dogs?
Boxers, basenji’s, beagles, bull terrier
Giant hypertrophic pyloric gastropahty occurs in what breeds of dog?
Aged small dog breeds - poodle, Pekingese, shih tzu
What is the main benign gastric neoplasm? Malignant gastric neoplasm?
Benign - adenoma
Malignant - adenocarcinoma, lymphoma, squamous cell carcinoma, leiomyoma
Rodent ulcer in cats is is caused by what inflammatory cell?
Eosinophils - rodent ulcer = eosinophilic granuloma complex
Important types of cell in the intestines?
Epithelium, mucous cells, enterochromaffin cells, M cells, mesenchymal cells (lymphocytes, neutrophils, eosinophils, globular leukocytes)
Non-immunologic defense mechanisms of the intestine includes?
Secretions (mucins, mucus) - coats and protects epithelium
Indigenous microbial flora - compete for attachment, inhibitory substances
Gastric barrier (acid and digestive enzymes)
Intestinal motility and feed movement
Epithelial turnover and repair
Bile salts - inhibit bacterial growth
Liver - second line of defense
Immunologic defense mechanisms of the intestine includes?
Secretory antibodies - IgA
Cellular defense
Diarrhea = increase in one of more of the following (3)
Frequency, fluid, volume
Mechanisms of diarrhea?
- Increased permeability of mucosal epithelium
- Hypersecretion (mucosa is structurally intact) - usually d/t enterotoxins
- Exudation (increased capillary or epithelial permeability)
- Malabsorption/maldigestion
- Intestinal hypermotility
- Non-intestinal diseases
Malabsorption vs. maldigestion?
Malabsorption = results from diminished digestion or nutrients into smaller molecules, absorptive capacity of the intestine, and/or transport of products once absorbed
Maldigestion = defective hydrolysis of nutrients, usually pancreatic in origin
Maldigestive issues are usually pancreatic/hepatic in origin
Pancreatic
Intestinal changes that could result in malabsorption?
Reduced mucosal SA (villus atrophy), infiltration of inflammatory and immune cells, loss of mucosal brush border enzymes, lymphatic obstruction (block transport of digested nutrients)
Enteritis = ?
Colitis
Typhlitis
Typhlocolitis
Inflammation of the SI
Colon
Cecum
Colon + cecum
Hemorrhagic enterocolitis is commonly caused by what agent?
Clostridium
Fibrinonecrotic entercolitis is commonly caused by what agent?
Salmonella
Ulcerative enterocolitis is commonly caused by what agent/factors?
BVDV, ischemia
Suppurative or pyogranulomatous enterocolitis is commonly caused by what agent?
Rhodococcus
Proliferative or hyperplastic enterocolitis is commonly caused by what agent?
Coccidiosis
Granulomatous enterocolitis is commonly caused by what agent?
Johne’s - mycobacterium
Equine granulomatous enteritis
Main agents that cause viral enteritis?
Rotavirus and coronavirus
Rotavirus vs. coronavirus?
Rota - younger calves (2-9 days), yellow diarrhea
Coronavirus - older calves (4-21 days), winter dust enters in older cattle, more virulent
Both - necrosis of apical epithelium
Bovine viral diarrhea virus: transmission routes? Forms? Gross appearance?
Routes = direct contact postnatal, Viremia prenatal
Forms = acute, chronic, fetal, persistent infection
Appearance = linear ulcers throughout GI tract, well-demarcated foci of necrosis in epithelium over GALT
What is the primary antibody of the alimentary tract?
IgA
The predominant inflammatory cell associated with “rodent ulcer” of the feline lip and gingiva is:
Eosinophils (eosinophil granuloma complex)
Canine parvovirus enteritis: what tissue types does it infect? What blood disorder does it cause?
Rapidly dividing - SI crypt enterocytes, lymph nodes, myeloid stem cells
Panleukopenia
Enterotoxigenic colibacillosis (ETEC): mechanism of action of enterotoxins produced? causes what type of diarrhea?
Enterotoxins induce Na+ and Cl- secretion into lumen, pulls water with it, decreased fluid absorption, dehydration
Secretory
Enteroinvasive colibacillosis (EIEC): name of toxin produced? Name of characteristic necropsy finding?
Shiga
White spotted kidney disease
Enteropathogenic colibacillosis (EPEC)/attaching and effacing E. Coli (AAEC): what structure do they form? What do they produce/inject into host cell? What structure do they disrupt?
Pedestals and cups
Intimin receptor
Brush border of enterocytes
Enterotoxemic colibacillosis (edema disease in pigs): produces widespread systemic … endothelial injury
Vascular
What is the basic cause of foamy bloat in ruminants?
Excess soluble leaf protein in the diet
Salmonella virulence factors? Characteristic lesion if chronic in pigs?
Flagella, fimbriae, LPS, intraphagocyte survival, toxins
Button ulcers
Clostridium species are categorized in types based on what?
The exotoxins they produce
Clostridium perfringens type D: produces which exotoxins? Can be related to a change in … . Can cause enterotoxemia
Alpha and beta, diet
Clostridium perfringens type C: produces which toxin? Why are neonates affected more often?
Beta. Toxins are susceptible to trypsin but colostrum has antitrypsin effect.
Clostridium difficile: zoonotic or not? What is major risk factor for disease? Affects what species?
Yes, antibiotic use, primates/foals/lab animals
Johne’s disease agent = ? Main clinical findings?
Mycobacterium avium subspecies paratuberculosis. Hypoproteinemia, weight loss, chronic wasting, thickened mucosal folds in ileum and LI, macrophages with acid-fast bacilli.
Lawsonia intracellularis aka … disease
Tyzzer’s
How does Rhodococcus equi infiltrate the intestines? Main clinical sign?
Enter via M cells overlying GALT
Pyogranulomatous lymphadenitis
Cryptosporidiosis: most common in what species/age? Location of agent?
Calves, intracellular and extracytoplasmic
Verminous arthritis in horses: caused by what agent? What vessel is affected?
Strongylus vulgaris
Cranial mesenteric artery - supplies the bowel
… commonly obstruct horses at the pelvic flexure of the transverse colon
Enteroliths
Which of the following is the major risk factor for gastric ulcer development in pigs?
A. Increased stress
B. Helicobacter spp. infection
C. Mast cell tumor
D. Finely ground feed
D
What is one of the most characteristic lesions associated with mucosal disease caused by bovine viral diarrhea virus in cattle?
Linear esophageal ulcers
