GI 1, 2 and 3: Upper GI tract Flashcards
What epithelium lines the lip, tongue and oral cavity?
Lip- squamous epithelium, keratinised
Tongue- squamous epithelium, not keratinised, papillae
Oral cavity- squamous epithelium, not keratinised
What developmental abnormalities do these images show?
Left- cat cleft palate
Right- inferior agnathia
What terms are used to describe oral developmental abnormalities?:
part of mouth not present
short either maxilla/mandible
One of the above affecting mandible
One of the above affecting maxilla
Agnathia- not present
Brachygnathia (short), Prognathia (long)
Superior- maxilla
Inferior- mandible
What can cause neurogenic atrophy of lingual muscles?
-part of tongue atrophies
- Damage to the hypoglossal nerve in horses- guttural pouch mycosis
- Starvation- lack of nutrients
- Lack of blood supply- chronic hepatic congestion
- Lack of innervation- nerve transection
- Disuse
- Pressure- neoplasia
- Loss of hormonal stimulation- testicular atrophy
When do the following oral circulatory disorders occur?:
Pallor
Cyanosis
Petechial haemorrhage
Pallor- anaemia/heart failure
Cyanosis- blue or purple colouration of mucous membranes due to the tissues near the skin surface being low on O2- uraemia, nitrate poisoning, blue tongue
Petechial haemorrhage [lots of little dots]- clotting defect, septicaemia, intoxications
What do the following terms mean?:
Stomatitis
Chelitis
Gingivitis
Glossitis
Palatitis
Sialoadenitis
Tonsilitis
Phraryngitis
- Stomatitis- inflam of the oral cavity
- Chelitis- inflam of the elips
- Gingivitis- gums
- Glossitis- tongue
- Palatitis- hard or soft palate
- Sialoadenitits- salivary glands
- Tonsilitis- I mean yeh come one
- Pharyngitis- use your creativity
What can cause gingivitis?
What are the associated conditions?
- Poor oral hygiene
- Opportunistic bacterial infections
- Gingival trauma
- Immunodeficiency
Associated conditions
Stomatitis, oral ulceration, glossitis
Eosinophilic granuloma complex- cat
Tonsilitis
secondary to periodontal disease
What is the agent of necrobacillus?
What is its alternative name?
What are the clinical signs?
Describe the pathogenesis
Agent- fusoforum necrophorum
AKA- calf Diptheria
CS- swollen and dribbling
Path- invasion and colonisation of damaged mucosa as commensal/opportunistic pathogen, extensive necrosis due to toxins
What agent causes wooden tongue?
How does it invade and what does it lead to?
What is the DDX?
Agent- opportunistic actinobacillus ligniersi
Invasion and colonisation of damaged mucosa
This leads to pyogranulomatous inflammation with extensive fibrosis and abscess formation
DDX- jumpy jaw (osteomyelitis of mandible due to actinomyces bovis)
What viral agent is responsible for blue tongue?
Describe its pathogenesis
How do early phase and chronic findings differ?
Orbivirus
Pathogenesis- insect bite by culicoide spp, viraemia, infection of endothelial cells, endothelial damage leading to microthrombi, haemorrhages and ischaemic damage
Early phase- hyperaemia/oedema of oral and nasal mucosa- cyanosis of tonuge
Late phase- ischaemic necrosis
When viral diseases cause vesicles what is the common term?
Why do they occur?
Blisters
Due to ballooning degeneration of epithelial cells
What species are affected by foot and mouth disease?
What is the route of infection?
Where are ulcers commonly located?
Describe the pathogenesis
Species- cattle, swine, sheep- clinically silent in wild ruminants
ROI- aerosol/oropharyngeal infection
Ulcers-
Tongue, lips, palate, skin near coronary band to interdigital space, ruminal mucosa
Pathogenesis
- Tropism for squamous epithelial cells
- Ballooning degeneration of cells
- cells detach
- Oedema and fibrin fills space- vesicles
- Vesicles coalesce- bullae
- Erosion/ulcers
What are the DDXs for viral disease-causing erosive and ulcerative stomatitis?
BVD- mucosal disease
Bovine malignant catarrhal fever
Blue tongue
What agent causes BVDV?
What presentation does it mainly occur?
What if the animal is pregnant?
When does mucosal disease occur?
How does mucosal disease appear?
Pestivirus BVDV type 1
BDV- mainly acute diarrhoea and rhinitis
Pregnant
1/3- abort
2/3- viraemic calf
3/3- ok calf
MD occurs in persistently infected calves
Grossly-
in oral mucosa and muzzle
In oesophageal, abomasal and intestinal mucosa
What viral agents cause malignant catarrhal fever?
When do animals become infected?
What lesions does it cause?
What diseases are associated with it?
Due to ovine herpesvirus type 2 or alcelahpine herpesvirus type 1
Sporadic disease observes in animals in contact with sheep
Erosions in oral oesophageal, abomasal and intestinal mucosa
Often associated with conjunctivitis and keratitis
What viral disease can cause erosive and ulcerative stomatitis in cats?
Feline calicivirus disease
Feline herpes virus infection- cat flu
What fungal agent mainly affects young suckling animals- especially when in poor hygiene conditions?
Candida albicans- Candidasis
Can infect immunocompromised adults
What parasites can infect the upper GI tract?
Cysticercus cellulosae- lingual muscle pigs
Larvae of Taenia solium
Cysticercus bovis- lingual muscle Cows
Larvae to T.saginata
Trichinella spiralis and sarcosporidia in the lingual muscle
What idiopathic inflammatory process can affect cats?
How can it present?
Eosinophillic granuloma complex- cat
Eosinophilic indolent ulcer- upper lip
Oral eosinophilic granuloma- tongue, soft palate
Eosinophilic plaque- abdomen, thighs
What bacteria can colonise tonsillar crypts?
Haemolytic streptococci
Certain coliform bacteria
What benign and malignant neoplasms can affect the oral cavity?
Benign-
- Papillomas
- Epulides
Malignant-
- Squamous cell carcinoma
- Melanoma
- Fibrosarcoma
- Osteosarcoma
What condition does this image show?
What species are affected?
Where can the lesions be found?
What are of animals are more commonly affected?
What agent induces the condition?
What is usually done?
Viral papillomas
Dogs, cats, cattle, rabbits- most
Oral and labial mucosa
Mainly younger animals
Induced by papillomavirus
Spontaneous regression probable
What species are commonly affected by epulides?
What tissue do epulides derive from?
What are the three subtypes?
Dogs
Derive from periodontal ligament or connective tissue
Sub types-
- Fibrous epulis- expansile, no invasion, composed of fibroblasts and collagen
- Ossifying epulis- fibromatous epulis, but with bone formation
- Acanthomatous epulis- contains stratified epithelium, invades underlying bone
Where does an oral squamous cell carcinoma derive from?
In what species is it the most common oral malignant neoplasm?
In what species is it the second most common?
Where does it commonly metastasise to?
What does squamous cell carcinoma frequently invade?
Deriving from oral squamous epithelium
Cats- most common malignant
Dogs- second most frequent
Metastasis to regional lymph nodes
Frequent invasion of adjacent soft tissue, skeletal muscle and bone
What can be sequelae of squamous cell carcinomas commonly in dogs?
How does it appear histologically?
Tonsillar squamous cell carcinoma
Early metastasis into regional lymph nodes- larger than primary tumour
Histo-
multifocal squamous differentiation and pearl formation- compact eosinophilic material
Basal membrane is focally interrupted and infiltrated by chords of neoplastic cells that infiltrate the lymphoid tissue
What do melanomas derive from
What species are they most common in?
Why is the prognosis very poor?
Why can they rarely grossly appear differently?
Deriving from melanocytes from pigmented mucosa
Dogs- most common
Highly invasive- early metastases- haematogenous and lymphatic to lungs and LNs
Rare amelanotic forms too
Where does an oral fibrosarcoma originate from?
What species is the second most common malignant neoplasm of the oral cavity?
What is common with fibrosarcomas?
Deriving from the connective tissue of the oral cavity
Cat- second most frequent malignant
Frequent invasion of underlying connective tissue, skeletal muscle and bone.
Can lead to widespread metastases
Looks similar to squamous cell carcinoma
What pathological diseases can affect the teeth?
Abnormal tooth wear- attrition
Tartar/inflammation-
Periodontitis etc
Odontogenic tumours
What animals are attrition important in?
What can cause reduced attrition with a lack of counterpressure?
What can it lead to?
All- especially herbivores
Reduced attrition
- Missing teeth- oligodontia
- Interdental gaps- diastasis
- Mal-alignment
Leads to
- Abnormally long teeth
- Mucosal lesions
- Difficulties chewing
- Impaction of food material
What is tartar?
What is periodontitis?
What are the stages?
Tartar-
Calcified masses of- food particles, bacteria, fungi, shed epithelium, leukocytes
Periodontitis- inflammation of tissues which surround the teeth
Stages
- Gingivitis
- Pocket formation in the gingival socket
- Loosening and loss of tooth
- Fistula formation
What type of neoplasms are odontogenic tumours?
Where do they derive from?
What are the two types?
Usually benign- rare
Arise from epithelial/mesenchymal tissue that gives rise to teeth
Ameloblastoma- dogs
arises deep within the mandible or maxilla, solid/cystic masses within the gingiva, teeth are loose or missing
Odontoma-
Dental malformation rather then true neoplasm
Complex- all normal tissue elements of tooth but malformed
Compound- masses of tooth-like tissue, but abnormally arranged
Image shows salivary glands slide
Can you identify the following structures?:
- Ganglion cell
- Artery
- Mucous acini
- Excretory duct
- Intercalated duct
- Serous acini
- Interlobular connective tissue
- Interlobar ducts
What are the following conditions of salivary glands?
Saloadenitis
Sialoliths
Ranula
Saloadenitis- rare
Salivary calculi- sialoliths
formed in duct or gland- chronic inflammation or foreign bodies
Ranula- cysts in sublingual duct
often located in the tongue frenulum, due to dilation and secretion with occluded duct
What kind of muscle makes up the tunica muscularis of the oesophagus?
Dogs
Ruminants
Pig
Cat
Horse
Dogs and ruminants- striated muscle
Pig-striated except for a short distance in front of stomach
Cat and Horse- striated 2/3
What commonly causes oesophageal compression?
What species is most likely to have oesophagus stricture?
What causes oesophageal stricture?
What causes oesophageal obstruction?
What are the sequelae?
Compression- masses in adjacent tissues
Stricture- mainly in dogs
Mainly due to the persistence of the right aortic arch
Oesophagus gets trapped between- aorta/pulmonary artery/ductus arteriosus botalli
Obstruction-
usually due to foreign bodies, rarely due to neoplasia, abscesses, parasites
sequelae-
mucosal necrosis
Perforation- pleuritis
What are the outcomes of compression (stenosis), stricture and obstruction?
- Dysphagia
- Tympanic/stomach bloat
- Formation of diverticulum
- Oesophageal rupture/perforation
- Regurgitation- aspiration pneumonia
What can cause megaoesophagus?
Due to neuromuscular disorders but also distal obstructions of the oesophagus- atonic, flaccid oesophageal wall dilated by food- aspiration
Congenital- cats/dogs
Inherited- great dane, GSH, Irish setter
defect in distention- a sensitive reflex that coordinates the oesophageal function
Acquired- adult dogs, secondary to disorders disrupting neural reflex in swallowing
What diseases can cause acquired megaoesophagus?
How does dysautonomia cause megaoesophagus?
Acquired causes-
Distemper, neuronal storage disease, neoplasia, botulism, lead poisoning
Myasthenia gravis- most common cause
Dysautonomia-
Autonomic polyganglionopathy
Resulting in abnormal function of the sympathetic and parasympathetic nervous system- cats and dogs
Reduction in number of autonomic ganglia, chromatolysis in remaining neurons
What are the two pathogenesis of inflammation of the oesophagus?
Disease- mucosal disease, infectious bovine rhinotracheitis etc
Reflux- chemically induced
What are the two neoplasms deriving from the oesophagus?
What species are commonly affected with each?
Papilloma- cattle
Fibrosarcoma- Dog
What causes papilloma in cattle oesophagus?
What is fibrosarcoma in dogs associated with?
Cattle- BPV type 4- oral/pharynx/oesophagus/rumen
Fibrosarcoma- associated with long-standing spirocerca lupi infection
What kind of parasite is Spirocerca lupi?
What is its intermediate host?
Describe its life cycle and how it leads to fibrosarcoma formation
Nematode- dogs
Intermediate host- beetles
Life cycle-
- Ingestion of beetles with third-stage larvae
- In the stomach enter subintima of the gastric artery and aorta
- Migration to caudal thoracic area
- Migration to oesophagus
- Development in adult stage worms
- Oesophageal epithelium perforation
- Granulomatous oesophagititis
- Chronic- development of sarcomas
What epithelium lines the forestomach of ruminants?
From the image which are the reticulum, rumen and omasum?
Stratified squamous epithelium
Reticulum- honey comb
Rumen- lentils
Omasum- lumpy folds
What is parakeratosis/hyperkeratosis?
Loss of ruminal papillae
Regarded as an adaptive process to chemical changed in ruminal content
What is ruminal tympany?
Why does it occur?
What is the difference between primary and secondary?
In a severe case, how can it lead to death?
Accumulation of excessive quantities of gas (CH4 and CO2)
Caused by impairment of normal eructation causing distention of the rumen
Primary- frothy bloat
Gas is dispersed as small bubbles in ruminal fluid so cannot escape with eructation
Secondary- free gas
Less common, due to physical obstruction of oesophagus/pharynx or vagal indigestion
Describe the pathogenesis of primary ruminal tympany
- Access to lush pasture
- Lowers rumen pH (5.4)
- Mucolytic bacteria lead to decreased salivary function, lush pasture increases levels of soluble protein
- Both lead to decreased surface tension and increased surface viscosity
- Produces a stable foam
What disease can be caused by an abrupt change of diet, mainly seen in high production beef and dairy cattle
Ruminal acidosis
can lead to
Rumenitis
can lead to
Ulcers
Describe how rumen acidosis (lactic acidosis) can occur
What is the prognosis?
- Ingestion of highly fermentable carbohydrate- overgrowth of gram +ve bacteria- streptococcus bovis, lactobacillus
- This leads to increased lactic acid production and volatile fatty acids
- Increases lactic acids cause increased osmolarity and decreased pH
- Increased volatile fatty acids lead to cessation of rumination- atony
- Increased osmolarity leads to sequestration of fluid- osmotic diarrhoea- dehydration
- Decreased pH leads to ruminitis, endotoxaemia and therefore metabolic acidosis
Prognosis- death 25-90% when pH <4.5
What does this image of the rumen show?
What is the most likely cause?
What sequelae can come from this?
Rumen- rumenitis and ulcers
Cause-
lactic acidosis causes chemical rumenitis allowing for secondary infection
Rumenitis sequelae-
Bacterial entry to portal circulation- Leads to hepatic abscesses
Caudal vena cava- embolic pneumonia- cor pulmonae, caudal vena cava syndrome
What causes traumatic reticulitis in cattle?
What is the sequelae?
Due to swallowing of acute foreign material- nails
Foreign body perforates reticulum
Sequelae- chronic peritonitis/pericarditis
What are the different regions of the stomach?
What cells in the stomach produce: gastric acid, pepsinogen?
Fundus parietal cells- produce gastric acid
Chief cells- produce pepsinogen
What species are affected by gastric dilation and volvulus?
Describe the pathogenesis?
What predisposes to the disease?
What are the sequelae?
Species- dogs, horses, humans, pigs
Path-
Dilation- due to aerophagia and food/fluid, stomach rotates its long axis
Volvulus- 360 degrees, results in displacements, pylorus and terminal duodenum compressed between oesophagus and stomach, spleen moves
Predisposing
Dogs- deep-chested breeds- great dane, st bernard etc
Increased laxity of hepatogastric ligament, diet of small food particles
Sequelae
Gastric haemorrhagic infarction
Decreased venous return, decreased cardiac output, arterial hypotension, decreased renal function- shock
What cows are more commonly affected by abomasal displacement?
Where does it displace to?
What disease is often associated?
What are the sequelae?
Older dairy cows- time of parturition
Displacement to the anterior abdomen, usually ventrally left, sometimes right
Often with ketosis, hypocalcemia, metritis, retained placenta
Sequalae- haemorrhagic infarction, abomasal volvulus
What parasites can be found in a horse’s stomach?
Describe the pathogenesis and sequelae
Gastrophilus spp larvae (bot flies)
- Ova are deposited on hair and hatch spontaneously after licking and ingestion
- First stage larvae penetrate oral mucosa, moult and emerge to migrate down the alimentary tract
- Attach to squamous mucosa and induce erisions
What parasites can be found in ruminants’ stomachs?
What do they cause?
Sheep- haemonchus contortus, telodorsagia circumcinta
Cattle- ostertagia ostertagi
Blood sucking parasites-
Inflammation, erosions, ulcers, anaemia, cachexia, hypoproteinaemic oedema
What is allotiophagia?
What causes it?
The desire to consume inappropriate material
- Encephalitis- rabies
- Starvation
- Boredom
What are (zoo)trichobezoars? What can they lead to?
What are gastroliths seen in?
Why?
(Zoo)trichobezoars- impacted hair balls in abomasum of calves/stomach of angora rabbits
Can lead to rupture
Gastroliths- seen in horses, birds and reptiles
Stomach/gizzard stones- retained in gizzard and used to grind food
How does acute catarrhal gastritis appear?
What is the aetiology?
Increased reddening and thickening of the entire surface/parts of mucosa and increased mucosa production
Aetiology-
Poisons, infectious diseases, parasites
What does this image show?
What are the DDXs?
Acute haemorrhagic gastritis
DDXs
- Poisons
- Infectious diseases
- NSAIDs
-
Braxy- sheep in cold climates, due to clostridium septicum enterotoxin
severe oedema and emphysema in submucosa, haemorrhage/venous thrombosis
Describe the pathology of uraemic gastritis?
- Chronic renal failure leads to the excretion of a high concentration of ammonium in saliva and gastric juice
- Causes coagulative necrosis, haemorrhage, neutrophil inflammation, mineralisation
- Leading to endothelial damage and necrosis- thrombosis and then infarction
What is associated with fibrino-necrotising gastritis?
What is the aetiology?
Associated with mucosal destruction
Aet- Mycotic infection
When are gastric ulcers seen?
Different species have different aetiologies- wow!
What are the common locations and aetiologies in the following species?:
- Cattle
- Swine
- Foals/horses
- Dogs/cats
What are the outcomes?
Seen with erosive/ulcerative gastritis
Cattle- mainly calves
Mainly pylorus, associated with the environment
Swine- no you are!
In squamous epithelium, associated with hyperacidity, fine ground grain diet, stress
Foals/horses
mainly in the non-glandular portion, associated with gastrophillus larvae
Dogs/cats- plyorus/prox duodenum- mast cell tumours
Outcome-
Haemorrhage- vascular erosion- anaemia
Perforation leads to peritonitis
What species is gastric rupture most common?
What usually causes it, and what rarely does?
Where does rupture most commonly occur in the stomach?
What follows within a few hours?
How is an intravitral rupture identified?
Most common in horses
Usually due to dilation- rarely trauma
Along greater curvature- serosal tear > muscularis > mucosa
Death within a few hours- intoxication and shock
Id of intravital rupture
Irregular borders
Haemorrhage
Ingesta particles in omentum and close to rupture
What can cause gastric dilation in horses and result in rupture?
Primary-
after consumption of excess fermentable carbohydrates, sudden access to lush pasture and excessive intake of water
Secondary-
Sequel to obstruction of the SI or colic with ileus- grass sickness
Idiopathic
What are the main primary and secondary gastric neoplasms?
Primary-
- Adenocarcinoma
- Adenoma/benign adenomatous polyps
- Squamous cell carcinoma
- Lymphosarcoma
- Leiomyoma/Leiomyosarcoma
- Carcinoids
Secondary-
- Lymphosarcoma
- Mast cell tumour
- Metastatic from pancreas and liver
What is the most common gastric neoplasm in dogs?
Where does it derive from?
Where is it commonly found?
What are the characteristics of its growth and development?
Adenocarcinoma
Arising from the epithelium of glandular mucosa
Mostly in pyloric antrum along the lesser curvature
Characteristics-
Locally widespread growth
Invasive growth
Superficial ulceration
Metastases to regional lymph nodes, liver and lung
Where does squamous cell carcinoma arise from?
What species are more commonly affected and why?
Does it metastasize?
Arises from squamous epithelium of cardia
Mostly in species with large proventricular area- horse, rat, pig
Invasive growth
Occasionally- lymphatic invasion, metastases
Where do leimyoma/sarcoma arise from?
Where does lymphosarcoma arise from?
Leiomyoma- smooth muscle cells in tunica muscularis
Lymphosarcoma- lymphoid tissue
Primary or secondary
Primary in cats
