Gastroenterology - Small Intestine Flashcards
What are the functions of the small intestine?
- digestion of food
- absorption of nutrients
- barrier to infection
What makes up the villi?
- enterocytes
- digestive enzymes, carrier proteins, and goblet cells
- crypt cells
- lamina propria
- mucosal immune system
What is the main energy requirement for enterocytes?
glutamine
What is HGE and AHDS?
- Hemorrhagic Gastroenteritis
- Acute Hemorrhagic Diarrhea Syndrome
Which animals are more predisposed to HGE and AHDS?
small breeds
What is the result of HGE and AHDS?
marked hemoconcentration and fluid shifts
- typically requires hospitalization
- hypovolemic shock seen before dehydration
What are the clinical signs of HGE and AHDS?
hematemesis and hematochezia
What are the possible etiologies of HGE and AHDS?
- viral
- hypersensitivity reaction
- infection by Clostridium perfringens
How is HGE and AHDS treated?
- IV fluids
- antibiotics
- gastroprotectants
- antiemetics
- nutrition
What is the prognosis for HGE and AHDS?
- good with aggressive supportive care
- poor with severe hypoproteinemia or signs of sepsis
What tapeworms can infect the small intestine?
- Dipylidium caninum
- Taenia
- Echinococcus
How does an animal get infected with Dipylidium caninum?
ingestion of fleas
What is the typical sign associated with Dipylidium caninum infection?
peri-rectal irritation
What is the treatment for Dipylidium caninum?
Praziquantel
Fenbendazole
How is Toxocara canis/cati transmitted?
ingestion of eggs or maternal transmission
What are the clinical signs associated with Toxocara?
- vomiting of live worms
- unthriftiness
- diarrhea
What is the treatment for toxicara?
Fenbendazole
Pyrantel Pamoate
What are the clinical signs associated with protozoa infections?
diarrhea +/- weight loss
What is the pathology of a protozoa infection?
destruction of enterocytes and villi
How is Giardia diagnosed?
- direct smear
- cysts on fecal float
- IFA
- ELISA
How is Tritrichomonas foetus diagnosed?
- direct smear
- culture
- fecal PCR
What is the treatment for Giardia?
Fenbendazole +/- Metronidazole
How is Coccidia transmitted?
fecal-oral or predation
What are the clinical signs of a coccidia infection?
- weight loss, dehydration, +/- hemorrhage
- adults can be self-limiting
- young/immunocompromised: anorexia, vomiting, dehydration
How is Coccidia diagnosed?
- direct smear
- fecal float
How is Coccidia treated?
Sulfadimethoxine and supportive care
How is Cryptosporidium transmitted?
- fecal-oral
- contaminated food/water
What are the clinical signs of a Cryptosporidium infection?
- self-limiting small bowel diarrhea
- can extend into large intestine and other organs
How is Cryptosporidium diagnosed?
- direct smear and fecal float
- ELISA
- PCR
- Biopsy
How is Cryptosporidium treated?
Paromomycin
Tylosin
How is Toxoplasma gondii transmitted?
predation and fecal contamination
What are the clinical signs of toxoplasma infection?
- pneumonitis
- GIT signs
- encephalitis
- lymphadenopathy
- liver disease, pancreatitis
- chorioretinitis
- fever, weight loss, lethargy
How is Toxoplasma gondii diagnosed?
- fecal float (limited use)
- antibody titers (IgG, IgM)
How is Toxoplasma gondii treated?
- Clindamycin
- Trimethoprim-sulfonamide
- Supportive care
What is Pythium Insidiosum and how is it transmitted?
- aquatic fungus
- exposure to free standing water > penetration of skin or mucosa by zoospores
What are the clinical signs of a Pythium Insidiosum infection?
GIT - vomiting, weight loss, SI diarrhea, hematochezia, abdominal pain
Derm - non-healing skin lesions
What is seen on CBC/Chem with a Pythium Insidiosum infection?
- eosinophilia, anemia
- hypoalbuminemia, hyperglobulinemia
How is Pythium Insidiosum diagnosed?
- CBC/Chem
- ELISA
- culture
- FNA of lesions
- biopsy
- radiographs and ultrasound
What is seen on biopsy of a Pythium Insidiosum infection?
- severe transmural segmental thickening
- pyogranulomatous and eosinophilic inflammation
How is Pythium Insidiosum treated?
- surgical removal of limb or GI segment
- Itraconazole, Terbinafine
- immunotherapy in non-resectable cases
What is Histoplasmosis and how is it transmitted?
- dimorphic fungus
- aerosolization to lungs and LNs
- into GIT or bloodstream
What are the clinical signs of a Histoplasmosis infection?
- diarrhea, fever, weight loss to emaciation
- chronic cough, respiratory difficulty
- lameness, anemia
- hepatomegaly, splenomegaly, lymphadenopathy
- nasopharyngeal and GI ulcerations
- skin lesions
How is Histoplasmosis diagnosed?
- chest radiographs for lung nodules and LNs
- ultrasound (thickened intestinal walls)
- FNA, biopsy, culture, ELISA
How is Histoplasmosis treated?
Severe cases - Itraconazole, Amphotericin B
Mild cases - Fluconazole, Ketoconazole
What is Candida?
normal fungal inhabitant of nasopharynx, GIT, and genitalia
What are the clinical signs of Candidiasis in cats?
- oral and URT disease
- pyothorax
- ocular lesions
- intestinal disease
- cystitis
What are the clinical signs of Candidiasis in dogs?
peritonitis and fungemia
What are the top 3 bacteria associated with intestinal disease?
- Salmonella
- E. coli
- Campylobacter
How is Salmonella transmitted, and what is the pathology?
- raw and/or contaminated foods
- destroys intestinal villi
How does a dog acquire Salmon Poisoning disease?
Ingestion of salmon infected with flukes carrying the bacteria
- Neorickettsia helminthoeca/elokominica
What are the clinical signs of Salmon poisoning disease?
- high fever
- hematemesis, diarrhea, vomiting
- lethargy, anorexia
- nasal and ocular discharge
- enlarged lymph nodes
How is Salmon poisoning disease diagnosed?
- fluke eggs in feces
- history of ingested fish
- inclusion bodies in macrophages
- PCR, serology
- thrombocytopenia
How is Salmon poisoning disease treated?
- hospitalized support
- Oxytetracycline, Doxycycline
- Praziquantel for the fluke
How is Canine Parvovirus Enteritis transmitted?
- fecal oral transmission
- affect dogs shed virus while sick
- can remain infectious in environment for months
- highly contagious
What are the clinical signs associated with Canine Parvovirus Enteritis?
- often severe
- anorexia, depression
- vomiting, diarrhea
- hypothermia
- dehydration
How is Canine Parvovirus Enteritis diagnosed?
CBC - leukopenia, neutropenia, lymphopenia, and thrombocytopenia
Chem - hypoglycemia, hypoproteinemia
ELISA of feces or tissue
Hos is Canine Parvovirus Enteritis treated?
- fluids
- symptomatic: antacids, antiemetics, analgesics
- antibiotics
- nutrition
- pro-motility agents
What are the complications associated with Canine Parvovirus Enteritis?
- sepsis
- intussusception
- peumonia
- DIC
What is the prognosis for Canine Parvovirus Enteritis?
if survive the first 3-4 days, likely to make a full recovery
What are the clinical signs of Feline Panleukopenia?
- similar to CPV enteritis
- hemorrhagic enteritis
What can occur with a peri-natal infection of Feline Panleukopenia?
cerebellar hypoplasia
How is Feline Panleukopenia diagnosed?
Parvo SNAP test
Describe coronavirus infection in the cat
- self-limiting to moderate diarrhea
- can be subclinical
- can mutate to FIP
What is the treatment for a small cell lymphoma?
Chlormabucil and Prednisolone
Which intestinal neoplasms do cats get?
- Lymphoma
- Adenocarcinoma
- Mast cell
Which intestinal neoplasms to dogs get?
- Lymphoma
- Adenocarcinoma
- Smooth muscle tumors
What is exocrine pancreatic insufficiency?
insufficient secretion and production of pancreatic enzymes
- leads to maldigestion
What are the possible causes of exocrine pancreatic insufficiency?
- pancreatic acinar atrophy
- chronic pancreatitis
- aplasia or hypoplasia
What are the clinical signs of exocrine pancreatic insufficiency?
- # 1 is weight loss
- loose stools, steatorrhea
- ravenous appetite
- poor hair coat
- borborygmi
- flatulence
How is exocrine pancreatic insufficiency diagnosed?
- MDB to rule out other causes
- TLI level
- low B-12
How is exocrine pancreatic insufficiency treated?
- exogenous pancreatic enzyme
- fresh pancreas
- pancreatic tablets and capsules
What is the principle behind hydrolyzed diets?
split proteins to such a small size, that the immune system cannot recognize them as foreign
What is antibiotic responsive diarrhea, and what is it due to?
small intestinal bacterial overgrowth
- defects in mucosa
- aberrant mucosal immune response
- qualitative change in enteric flora
What are the clinical signs associated with antibiotic responsive diarrhea?
- small intestinal diarrhea
- +/- LI diarrhea and weight loss
- stunted growth
- borborygmi, flatulence
- appetite change
- vomiting
How is antibiotic responsive diarrhea diagnosed?
- response to treatment trial
- biopsy may or may not show concurrent disease and inflammation
How is antibiotic responsive diarrhea treated?
- 4-6 weeks of medication
- Metronidazole, Tylosin
What is Inflammatory Bowel Disease?
- disease of dogs and cats with chronic GI signs for which no other cause is documented
- non-responsive to parasiticides, antibiotics, or diet trials
What are the possible causes of inflammatory bowel disease?
- disruption of the physiologic interaction of innate and adaptive immune response
- defective mucosal barrier
- inappropriate reaction to commensal bacteria or food antigen
What can be include in inflammatory bowel disease?
- mild to severe inflammatory infiltrates
- loss of normal villous structure
- fibrosis
- goblet cell changes
- abscesses and cysts
- lymphangiectasia
- protein losing disease
What is the most common infiltrate in inflammatory bowel disease?
lymphoplasmacytic infiltrate
What are the treatment options for a minimal change enteropathy?
- deworm: Fenbendazole
- diet trial
- antibiotic trial
What are the different types of inflammatory bowel disease?
- minimal change
- granulomatous or neutrophilic
- lymphoplasmacytic
- eosinophilic
What is lymphangiectasia?
- diseased dilated lymphatics
- inflammation can block lymphatic flow
- a common cause of protein-losing enteropathy
What are the effects of lymphangiectasia?
- exudation of protein-rich lymph into the intestine
- severe malabsorption of fat and other nutrients leading to PLE
What are the clinical signs associated with lymphangiectasia?
- decreased appetite, weight loss
- vomiting, diarrhea
- ascites
What is found on endoscopy with lymphangiectasia?
- white granules/blebs on mucosal surface
- abnormal distension of lymphatic vessels
What are the treatment options for lymphangiectasia?
- diet (hydrolyzed and low fat)
- antibiotics (Metro or Tylosin)
- immunosuppressants (Pred, Cyclo)
- thromboprophylaxis (Aspirin or Clop)
- diuretics for ascites
What is a protein-losing enteropathy?
- severe malabsorptive small intestinal disease
- leads to loss of albumin +/- cholesterol an other important proteins and nutrients
