LEC 14 - GI V Flashcards
What does the parvovirus type 2 infect in regards to cell type?
Dividing cells in the crypts of the intestines
What type of tropism does parvovirus type 2 have?
Radiomimetric
Where does initial replication occur in parvovirus?
Lymphoid tissues
What are the early lesions seen with Parvoviral enteritis?
Lymphoid depletion
Thymic involution
What are the late stage lesions seen with Parvoviral enteritis?
Red
Fibrinous exudate in lumen
Flaccid segments of SI
Serositis
Depletion of bone marrow
What late lesion is only seen in dogs with parvoviral enteritis?
Coagulative lymphadenitis
What happens to cats when they are infected with parvovirus type 2 in utero?
Cerebellar hypoplasia
What causes cerebellar hypoplasia in cats that get an in utero parvo virus infection?
Alteration of differentiation of layers in cerebellum at organogenesis
What is seen upon histological examination of parvoviral enteritis?
Villus atrophy due to crypt destruction
Intranuclear basophilic inculsion bodies
Enterocytes + Lymphocytes infected
What are other names for parvoviral enteritis in cats + minks + raccoons?
Panleukopenia
Cat distemper
Feline enteritis
Mink enteritis
What dog breeds are at an increase risk of parvo virus infection?
Rottweilers
Dobermans
Canine parvovirus syndrome: < 2 weeks
Generalized disease
Necrosis of rapidly dividing tissues
Canine parvovirus syndrome: 3 to 8 weeks
Myocarditis
Canine parvovirus syndrome: > 8 weeks
Hemorrhagic enteritis
Panleukopenia
What is the gross presentation of parvoenteritis?
Segments of SI diffusely reddened
Serosal surface is roughened + faintly granular + petechiated
Mucosa necrotic
Sloughing mucosa
What is the cause of minute virus of canids?
Canine Parvovirus Type 1
What is present in minute virus of canids?
Myocarditis + Respiratory disease
When does minute virus of canids cause fetal death?
If infection occurs at 25 to 35 days
What causes feline infectious peritonitis?
Feline enteric mutated coronavirus
What are the two forms of FIP?
Wet
Dry
Describe: Dry form of FIP
No effusion occurs
Describe: Wet Form of FIP
Fibrinous polyserositis
What cell type does feline enteric mutated coronavirus infect?
Macrophages
Where does inital replication of feline enteric mutated coronavirus occur?
Lymphoid tissues
What is the pathogensis of FIP?
Intital replication in lyphoid tissue
Macrophages infection
Carry virus systemic
Endothelial cells activated due to upregulation of MHC II
Non-neutralizing Ab’s
Immunocomplexes form
Vasculitis
What is the gross presentation of the wet form of fibrinous polyserositis?
Fibrin strands between viscera
Mats of fibrin on organ surfaces
White linear serpentine tracts in mesentery
Small nodules of intestinal serosa + surface of kidney
What causes the white linear serpentine tracts in FIP?
Type II hypersensitivity
due to immune complexes
What is the bacterial cause of histiocytic ulcerative colitis?
Suggest that it might be E. Coli
What population of dogs tend to get histiocytic ulcerative colitis?
Boxer dogs
Younger then 2 years
What gross lesions are seen with histiolytic ulcerative colitis?
Raised ulcerative nodules in colon
Lymphadenopathy
(Can be regional or generalized)
What is the histopathology of histiocytic ulcerative colitis?
Ulceration
Marked inflammation reaction (Composed of macrophages + intracytoplasmic PAS postive material)
In lamina propria of mucosa
What is the fungal cause of canine histoplasmosis?
Histoplasma capsulatum
Where is canine histoplasmosis most commmonly seen?
Ohio
Mississippi river valleys
How are dogs infected with canine histoplasmosis?
Yeast is inhaled or ingested
Invades tissues
Replicates in macrophages
Causes necrosis + granulomatous inflammation
What does the GI form of canine histoplasmosis look like grossly?
Mucosa is corrugated + thickened with ulceration
Granulomas in liver
Hepatomegaly
Lymphadenomegaly
Where can you see the microorgranism when a canine histoplasmosis infection is occurring?
Inside macrophages of lamina proria or ileum and colon
What organism causes salmon poisoning?
Neorickettsia hemlinthoeca
What is the basic life cyle of a neorickettsia hemlinthoeca?
Lives in a trematode
Affects salmon
Salmon ingested by a dog
What does neorickettsia hemlintoeca cause in a dog?
Necrosis of the GALT near the ileocecal valve
What gross lesions are seen with salmon poisoning?
Hemorrhagic + Granulomatous enterocolitis
What provides a diagnosis of salmon poisoning?
Macrophages containing Giemsa OR Gram-stained elementary bodies
How long does it take a dog to die from salmon poisoning?
10 days
What causes canine multifocal eosinophilic enteritis?
Larvae of Toxocara canis
At what age is canine multifocal eosinophilic enteritis most common?
Younger than 4 years
What happens when larvae of the Toxocara are in the mucosa in the GI tract?
Granulomatous nodules
What is the pathogenesis of Canine multifocal eosinophilic enteritis?
Larvae ingested
Invade mucosa of stomach + SI
Enter lymph vessels OR portal vein
Travel to liver + lung
L3 coughed up + swallowed
Mature/adult develops GI tracts
What is the characteristics of inflammatory bowel disease?
Lymphoplasmacytic enteritis
What breed are predisposed to inflammatory bowel disease?
Basejii
German Shepherd
What is the cause inflammatory bowel disease?
Unknown
What can inflammatory bowl disease in cats lead to?
Alimentary lymphoma
What dog breeds are predisposed to difffuse eosinophilic gastroenteritis?
German shepherd
Describe: Diffuse eosinophilic gastroenteritis
Increase in tissue + circulating eosinophilia
Suggests an hypersensitivity reaction
What gross lesions are present in diffuse eosinophilic gastroenteritis?
None
What is canine senile gastrointestinal amyloidosis characterized by?
Amyloid deposition in/around vessels of submucosa + muscularis layers
What disease processes are seen with canine senile GI amyloidosis?
No dysfunction seen
What does feline ulcerative colitis look like?
Histiocytic uclerative colitis in dogs
What does lymphagiectasia cause?
Protein-losing enteropathy in dogs
What is the cause of congenital lymphangiectasia?
Developmental disorders of lymphatics vessels
What is the cause of acquired lymphangiectasia?
Lymph vessels obstruction
What gross lesions are seen with lymphangiectasia?
Thickened mucosa with dialated lymphatics + lacteals in intestine
What can idiopathic intestinal lymphangiectasia lead to? Why?
Ascites due to protein-losing enteropathy
What is ileus?
Paralytic ileus is non-mechanical hypotitity resulting in functional obstruction
What can cause Ileus?
Paralysis of the wall
Peritonitis
Abnormal stimulation of splanchinic n.
Toxemia
Vitamin B-Complex deficiency
Uremia
Tetanus
Term: Trapped section in intussuception
Intussusceptum
Term: Enveloping portion in intussusception
Intussuscipiens
What breed of horse most commonly gets enteroliths?
Arabian breeds
Older than 4 years ofl
What are enteroliths most commonly made of?
Ammonium-magnesium phosphate
(Struvite)
Around a central nidus
Where do enteroliths normally lodge?
Pelvic flexure
– or –
Transverse colon
What commonly result in strictures?
Narrowing of the lumen of a canal
Normally due to healing of a scar
What is a common cause of a stricture in pigs?
Sequela of Salmonellosis
Thrombosis of cranial hemorrhoidal artery
What is atresia?
Occulsion of intestinal lumen as the result of anomalous development
How does atresia occur?
Result from lesions in fetal blood vessels
Most of the time caused by malpositioning + secondary vascular accidents/ischemia
What are the forms of Megacolon?
Acquired
– and –
Congenital
What animals does the congenital form of megacolon occur in
Pigs
Dogs
Cats
Overo foals
What is the cause of congenital megacolon?
Developmental lack of myenteric plexus secondary to failure of migration of neuroblasts from neural crest
What histological lesions are seen with equine overo?
Intestinal aganglionosis
What occurs with equine overo megacolon?
Colic develops
Die within 72 hours of birth
What causes acquired megacolon?
Secondary to damage to the colonic inervation
Atresia ani
