Diarrhea in the Cat and Dog Flashcards
define diarrhea, melena, flatulence, dyschezia, hematochezia, and tenesmus
diarrhea: increased frequency, volume, or fluidity
melena: dark, tarry feces
flatulence: excess gas
dyschezia: difficult or painful defecation
hematochezia: fresh blood in stool
tenesmus: ineffectual straining
differentiate acute versus chronic diarrhea
- signs can be intermittent, but if over 3 weeks = chronic and investigation is necessary
- acute: self-resolving, symptomatic treatment
give 5 differential diagnoses for acute diarrhea without systemic signs
- dietary indiscretion
- rotavirus, coronavirus
- helminths
- protozoa: giardia
- iatrogenic: drugs
give 4 differential diagnoses for acute diarrhea with systemic signs
- AHDS/acute hemorrhagic diarrhea syndrome/gastroenteritis
- acute pancreatitis
- parvovirus infection
- intoxications
mainstay of tx: fluids (replace losses and give the body time to try to resolve)
describe acute diarrhea workup
- definition: self-resolving in most cases
- tests (if any):
-parasites
-parvo: fluids + antibiotics
-if also vomiting: abdominal radiographs - if needed: fluids
- diets for acute diarrhea:
-highly digestible
-commercial veterinary therapeutic foods formulated for GI diseases or home-made diet
treatment guidelines:
-RARELY need antibiotics for acute diarrhea unless severe disease not rapidly improving with IV fluids
differentiate small versus large intestine chronic diarrhea
small:
-volume: LOTS
-mucus: none
-frequency: slight increase from normal
-tenesmus: none
-dyschezia: none
-weight loss: more common (decreased nutrient absorption)
-vomiting: can be present
-general condition: more likely to be affected than with LI
large:
-volume: slight increase from normal
-mucus: LOTS
-frequency: MUCH MORE than normal
-tenesumus: LOTS
-dyschezia: present
-weight loss: less common
-vomiting: can be present
-general condition: less likely to be affected than with SI
describe ddx for chronic small intestine diarrhea
EXTRA- GI
- metabolic:
-hepatic disease (PSS)
-hyperthyroidism (cats)
-Addison’s dz (dogs)
-renal insufficiency - pancreatic:
-EPI
-chronic pancreatitis
GI/intestinal:
- giardia infection
- chronic partial obstruction
- lymphangiectasia
- neoplasia: lymphoma
- food-responsive disease
- IBD
-lymphoplasmacellular
-granulomatous
describe ddx for chronic large intestine diarrhea
intestinal/GI only location for large intestine diarrhea (colon only!)
- IBD:
-lymphoplasmacellular
-ulcerative colitis (boxer) - polyps
- food-responsive disease
- neoplasia
- chronic partial obstruction
- cats: tritrichomonas foetus
-prevalence relatively high in catteries
-common in young purebred cats in crowded environments
-causes chronic colitis but not a lot of systemic disease
-dx: fecal smear, PCR (need PCR to diff from giardia)
-treatment: ronidazole BID for 2 weeks, not officially licensed for use in cats, neurological side effects, but other anthelmintics have NO effects
describe investigations for chronic diarrhea
- fecal exam:
-float, culture
-exclude parasites and bacterial infections - CBC, biochem, UA:
-exclude renal failure, hepatic disease, Addison’s - if small intestinal:
-consider serum tests: trypsin-like immunoreactivity, pancreatic lipase, cobalamin folate - abdominal ultrasound:
-where is lesion?
-is there an obstruction? - empiric treatment with elimination diet
-food responsive disease - if no response: biopsies (via endoscopy)
-multiple biopsies from stomach, proximal SI, ileum, and colon are possible
-non-invasive (except anesthesia)
-direct visualization of mucosa possible
-gives diagnosis for majority of cases
-difficulty: intestinal lymphoma, lympangiectasia
describe inflammatory bowel disease/chronic inflammatory enteropathy
- diagnosis by clinical exclusion!
- most common disease causing chronic diarrhea in dogs!
- subgroup of treatment responsive:
-food responsive
-steroid responsive
describe food responsive diarrhea
- diarrhea gets better when given elimination diet = feed a protein the animal has never eaten before
OR
- hydrolyzed diet:
-better within first 2 weeks
-keep on diet for at least 6-8 weeks
describe antibiotic responsive diarrhea
- formerly called small intestinal bacterial overgrowth
- most common in young large breed dogs
- chronic small intestinal or mixed diarrhea
- treatment: metronidazole or tylosin
-BUT usually relapse when abx discontinued so we don’t solely treat with antibiotics anymore
describe the effects of antibiotics on the microbiome
- metronidazole causes a huge shift in normal microbiome
-illustrated by dysbiosis index - C. hiranonis is key species: important for conversion of primary to secondary bile acids
- shift persists for at least 6 months after treatment in dogs with chronic diarrhea
why is microbial dysbiosis bad?
- commensals suppress inflammatory responses by binding to TLRs
- commensals prevent intestinal allergic reactions
- commensals elicit anti-inflammatory signals by binding to TLRs
if kill commensals you lose these benefits!
describe the microbiome in dogs with acute and chronic diarrhea
CE and acute diarrhea cause an increase in proteobacteria (E. coli) and a decrease in fusobacteria, bacteroides, and firmicutes
decreased diversity = dysbiosis
describe secondary bile acids in the intestines
- bile acids act as important antimicrobial molecules
- many bacteria will metabolize them to be able to survive
- if dysbiosis is present, this effect is gone
-results in pro-inflam changes in the intestine with permeability changes, resulting in chronic inflammation in the intestine
describe sequential treatment protocol of chronic enteropathies/IBD in dogs
- elimination diet first!!
- if no response:
-biopsies
-prednisolone
-cyclosporine if steroids poorly tolerated or not effective
describe treatment of IBD in cats
- try elimination diet (good luck)
- if not:
-prednisolone
-if no response: chlorambucil - cobalamin supplementation
describe protein losing enteropathy
- syndrome of intestinal diseases
- non-selective protein loss:
-albumins low
-globulins low
-both serum albumin and globulin low = very specific sign of PLE!! - causes:
-IBD
-lymphangiectasia
-neoplasia - clinical picture:
-diarrhea
-vomiting, anorexia
-weight loss
-ascites, pleural effusion, peripheral edema
-usually albumin and globulin serum concentration low = panhypoproteinemia
-IMPORTANT: biopsy early on in work up!
