Digestive Pathology Flashcards
Developmental diseases of the oral cavity
Cleft palate
Prognathism
Brachygnathism
Define cleft palate
Developmental abnormalities due to delayed development and fusion of the palatine arches
Etiologies of cleft palate
Genetic or toxic (plants, steroids during pregnancy)
Common complication of cleft palate
Aspiration pneumonia
Define prognathia or bradygnathia
Growth abnormalities resulting in long or short jaw, respectively
Etiologies of pro/bradygnathia
Genetic
Calcium deficiency
Chondrodysplasia
Possible consequences/problems associated with pro/bradygnathia
Malocclusion and tooth growth/wear abnormalities
Vesicular stomatitis/esophagitis causes
Viral (usually)
Thermal, toxic (rare)
What viruses can induce vesicular stomatitis/esophagitis?
FMD (picornavirus)
Vesicular exanthema (calicivirus)
Vesicular stomatitis (rhabdovirus)
Swine vesicular disease (enterovirus
The lesions associated with vesicular stomatitis/esophagitis are ___ lived. How do they progress?
Short-lived
Progress rapidly to erosions/ulcers
Erosive/ulcerative stomatitis causes
Viral
Toxic
Uremia
Immune mediated - pemphigus, SLE
What viruses can induce erosive/ulcerative stomatitis?
Calicivrius
BVDV
Bluetongue virus
Feline herpesvirus, rhinotracheitis
Proliferative stomatits/esophagitis causes
Parapox virus:
- Bovine papular stomatitis
- Contagious ecthyma
Necrotizing stomatitis causes
Bacteria
Infarctive
Banamine toxicosis?
What bacteria can induce necrotizing stomatitis?
Fusobacterium necrophorum
Actinobacillus
Other inflammatory lesions of the oral cavity?
Granulomatous
Pseudomembranous
What are granulomatous inflammatory lesions of the oral cavity normally associated with?
Deep bacterial infections, fungal infections
- Actinobacillus, cryptococcus, aspergillus
Neoplastic diseases of the oral cavity
Periodontal fibromatous epulis Acanthomatous ameloblastoma SCC Melanoma Fibrosarcoma
Periodontal fibromatous epulis location, histologic features
Location: anywhere on gingiva
HF: periodontal ligament, odontogenic epithelium, variable matrix of bone, dentin or cementum
Periodontal fibromatous epulis behavior if left untreated
Expansile, non-invasive - excision usually curative
Best one to have!
Acanthomatous ameloblastoma location, histologic features
Location: anywhere on gingiva
HF: interconnecting, invasive sheets of odontogenic epithelium
Acanthomatous ameloblastoma behavior if left untreated
Invasive to bone, no metastasis
Which oral neoplastic disease is most likely to metastasize?
Squamous cell carcinoma (especially tonsillar in dogs)
Gross features of squamous cell carcinoma
Nodular, firm, often ulcerated
Squamous cell carcinoma behavior if left untreated in cats vs dogs
Cats: locally invasive and mass producing, destructive to bone, 15% met to local nodes
Dogs: tonsillar mets to LN and distant sites, others are locally invasive, less likely to met
Most common oral tumor tumor in cats
Squamous cell carcinoma
Melanoma location and behavior if left untreated
Location: gingiva, lips most common
Behavior: met to regional LN and distant sites
Fibrosarcoma location and behavior if left untreated
Location: gingiva, hard/soft palate, lip tongue
Behavior: local infiltration and tissue destruction, met to local LN (20%)
What are the 4 pathologic processes associated with the esophagus?
Inflammatory disease
Megaesophagus
Impaction/obstruction
Neoplasia
Esophageal inflammation is generally comparable to inflammation in the oral cavity due to infectious agents. What is the exception?
Reflux esophagitis
Megaesophagus is due to ….
Insufficient or uncoordinated peristalsis
What is a consequence of esophageal obstruction/impaction in a horse?
Long-term can cause necrosis of the esophageal mucosa
What types of neoplasms are common in the esophagus?
Papilloma
Leiomyoma/leiomyosarcoma
Squamous cell carcinoma (rare)
What are the 3 pathologic processes associated with the rumen/reticulum/omasum?
Infectious inflammatory disease
Chemical rumenitis
Bloat/tympany
Infectious rumenitis/omasitis/reticulitis can be morphologically classified as…
Erosive/ulcerative Proliferative Necrotizing Pseudomembranous Granulomatous
Morphologic classification of mycotic omasitis?
Acute multifocal necrotizing and hemorrhagic omasitis
Chemical rumenitis is a(n) ____ disease due to ___ ___.
Inflammatory; lactic acidosis
Lactic acidosis etiology and chronic complications
CHO overload - devitalizes rumen flora
Complications: scars, mycotic infection, bacterial infection (hepatitis via portal vein)
What are the 4 pathologic processes associated with the stomach/abomasum?
Ulcers
Inflammatory disease
Rupture
Neoplasia
Conditions associated with stomach/abomasal ulcers
Trauma/chemical injury High acidity Local ischemia Helicobacter spp. Parasites Neoplastic disease: MCT and gastrin-prod tumors
Location varies depending on species. Where to stomach/abomasal ulcerations usually occur in horses, dogs/cats, pigs and cattle?
Horses = squamous part, along MP Cats/dogs = fundus d/t parietal cell density Pigs = pars esophageal (squamous/NG) - cardia region Cattle = anywhere
Conditions associated with abomasal ulcers in cattle?
Calving & early lactation in dairy cows
Rapidly growing calves fed 2X daily
Calves, cows/bulls treated with NSAIDs
Complications of abomasal ulcers in cattle
Fatal hemorrhage, chronic hemorrhage, perforation, peritonitis
Gastritis/abomasitis etiology
Infectious or toxic
Infectious causes of gastritis/abomasitis
Clostridial
Fungal
Parasitic
Helicobacter spp.
Why is gastric rupture more common in horses? If rupture caused death, what will you find?
Can’t vomit but produce reflux
Hemorrhage along ruptured border
Common neoplasms of the stomach/abomasum
Adenocarcinoma
Leiomyoma/leiomyosarcoma/GIST
Lymphoma
Squamous cell carcinoma - horse
Most common malignant tumor of horse stomach? Signalment? Prognosis?
Squamous cell carcinoma
Geriatric
Generally poor - usually already MET by the time dx
Causes of GI obstruction (8)
Gastric/abomasal volvulus Intestinal volvulus/torsion Intestinal external herniation Intestinal internal herniation/entrapment Intussusception Intestinal stenosis/atresia Intestinal stricture Enteroliths and impactions
What is a volvulus?
Twist of the stomach/intestine on self and mesentery
What are the consequences of gastric/abomasal volvulus?
Obstruction of lumen
Obstruction of vascular supply and hemorrhagic infarction
Torsion vs volvulus
Torsion = twist around the long axis of the intestinal segment (cecum) Volvulus = twist in axis outside the long axis of the organ, involving the mesentery (GI)
Examples of internal intestinal herniation
Through epiploic foramen
Mesenteric rent
Strangulating lipoma?
Name the enveloping/receiving and telescoping parts of the intussusception
Enveloping = intussuscepiens Telescoping = intussusceptum
Intussusception predisposing factors
Enteritis/altered motility
Intestinal FB
Intestinal polyp/neoplasm
Intestinal stenosis vs atresia
Stenosis = narrowing d/t fibrosis Atresia = congenital malformation leading to obstruction
Types of intestinal atresia
Membrane = attached via membrane only
Cord = only small cord-like membrane attachment
Blind end = no connection
Causes of vascular intestinal obstruction - name the associated species and etiology
Thrombosis/thromboembolism/infarction = horses with strongyloids
Intestinal lymphangectasia = dogs with maldigestion and PLE
Which segment of the intestine has villi and microvilli?
SI
Source of stem cell renewal in the intestines
Crypts
What viruses/fungal agents affect intestinal crypts (loss of normal crypt density)?
Parvovirus BVD Rinderpest Mycotoxins They cause systemic infection***
Aside from destruction of intestinal crypts, what other findings might you expect to see with parvovirus?
Thymic atrophy
Necrosis of Peyer’s patches
BVD hallmark finding
Necrosis of Peyer’s patches and crypt epithelial cells
What viruses/parasites wipe out villous tips?
Rotavirus - replication
Coronavirus - replication
Cryptosporidium - attach/replication
Localized infections only***
What are some consequences of villous infection?
Villi collapse, crypts increase in #, hyper secretion and leakage, villous atrophy
Mechanisms of enterocolitis/diarrhea
- Maldigestion/malabsorption = osmotic (villous atrophy)
- Secretory mechanisms = Cl secretion (crypt infectious agents)
- Increased permeability (mucosal epithelial damage)
Morphologic classification of enterocolitis according to exudate
Necrotizing Fibrinonecrotic Hemorrhagic Proliferative Granulomatous
Necrotizing enterocolitis resulting in villous atrophy etiologies
Viral
Protozoal
(Bacteria less common)
Known causes of infectious diarrheal disease in CALVES with villous atrophy
Coronavirus (TGE) Rotavirus Cryptosporidia Enteric calicivirus Norovirus Enteric syncytial virus - rota group B Parvovirus Astrovirus Some E. coli
Fibrinous/fibrinonecrotic enterocolitis etiology
Enteric salmonellosis = classic fibrinonecrotic lesions, fibrin casts
Pathogenic mechanisms for enteric salmonellosis
Attach to M cells, enterocytes, goblet cells
Survive in phagosome
Toxins induce necrosis - entero, ando, vero
Upregulate chloride secretion via prostaglandin
What are the three forms of enteric salmonellosis?
Peracute septicemia
Acute enteric salmonellosis
Chronic enteric salmonellosis
Peracute septicemia due to salmonella is characterized by ___ and ____
Vasculitis
Thrombosis
Acute enteric salmonellosis characterized by ___ and ____
Enterocolitis
Septicemia - hepatocellular necrosis, lymphadenomegaly, splenomegaly, fibrinous cholecystitis
Chronic enteric salmonellosis is characterized by ___, ____, and ____ in pigs
Enterocolitis
Thrombosis
Rectal strictures
All that is fibrinonecrotic is not salmonellosis. Other etiologies?
Enterotoxogenic e. coli
Clostridium dificile
Lawsonia intracellularis*
What bacteria causes colitis, but no SI lesions or enteritis in swine?
Brachyspira hyodyenteriae = swine dysentery
Hemorrhagic enterocolitis etiologies
Clostridial perfringens type C, otter clostridia
Shigellosis in primates
Lawsonia intracellularis
Coccidiosis
Proliferative/hyperplastic enterocolitis etiologies
Lawsonia intracellularis*
Coccidiosis
Granulomatous enterocolitis etiologies
Mycobacterial infection (Johne's)* Histoplasmosis (other deep mycoses) Less well define entities
Intestinal neoplasms
Lymphoma
Epithelial tumors - adenomas, adenocarcinomas
Leiomyoma/leiomyosarcoma/GIST
Carcinoid
Most common type of intestinal cancer in cat
Lymphoma
Location of intestinal adenocarcinoma in cats vs dogs
Cats: SI
Dogs: SI mostly, colon/rectum
Gross features of cat intestinal adenocarcinoma
Almost always annular and constrictive/obstructive
Gross features of dog intestinal adenocarcinoma
Almost always annular and constrictive (SI), plaque like or ulcerated, may be partially polypoid in colon/rectum
What breeds are predisposed to intestinal adenocarcinomas?
GSD, collies, siamese cats
Behavior of intestinal adenocarcinomas if left undetected/treated
Usually spread to local nodes and implant through peritoneum, and liver (dog)
