Gastroenterology, Pt. 5 Flashcards
Diarrhea; what is it? general properties
- Abnormal fluidity and/or frequency of fecal discharges
- Increased fecal water content
> Amount of fluid delivered by ileum > colonic absorptive capacity
> Increases fecal fluidity and/or volume (also from non-digestive content) - Increased frequency of defecation
> Due to increased fluidity and/or volume
> And/or primary alterations of motility - Enterosystemic cycle of fluid absorption and secretion
>- >98% of all fluid absorbed, most in jejunum, best in colon
MECHANISMS OF DIARRHEA (4)
1) Osmotic (villi)
2) Secretory (crypts)
3) Increased permeability (exudative)
4) Altered motility
- Disruption of enterosystemic cycle
- More than one mechanism often involved
osmotic diarrhea - how does it occur?
(villi)
* Unabsorbed nutrients (dietary overload, maldigestion, malabsorption), bacterial products
Secretory diarrhea - how does it occur?
(crypts)
* Bacterial enterotoxins, prostaglandins (inflammation), fatty acids
Increased permeability - how does it occur?
(exudative)
* Ulceration, inflammation, or neoplastic infiltration lead to leakage of fluid and ions ± proteins and red cells
Altered motility diarrhea - how does it occur?
- Increased peristalsis (primary rare), may occur as a consequence of increased fecal volume
- Decreased segmental contractions (common)
SMALL VS LARGE BOWEL DIARRHEA - why differentiaite?
- Severity of illness
> Takes less disease to cause large bowel diarrhea - Differential diagnoses
- Where to biopsy
small vs large bowel diarrhea:
frequency
small: N to slight up
large: up to super up
small vs large bowel diarrhea:
volume
small: N to slight up
large: down
small vs large bowel diarrhea:
mucous
small: no
large: likely
small vs large bowel diarrhea:
fecal blood
small: melena
large: hematochezia
small vs large bowel diarrhea:
steatorrhea
small: possible
large: no
small vs large bowel diarrhea:
borborygmus
small: possible
large: unlikely
small vs large bowel diarrhea:
tenesmus/dyschezia
small: no
large: common
small vs large bowel diarrhea:
attitude
small: more depressed
large: less depressed
small vs large bowel diarrhea:
hydration
small: more dehydrated
large: less dehydrated
small vs large bowel diarrhea:
weight loss (if chronic)
small: probable
large: uncommon
small vs large bowel diarrhea:
appetite (if chronic)
small: increased or decreased
large: often normal
bristol stool chart: what does it tell us
way of scoring poop based on texture
- 1 super hard balls, 7 liquid
- 4 is best
purina fecal score - what does it tell us
1 is hard lumps, 7 is liquid
- 2 is best
ACUTE COLITIS
¡ Differential diagnoses:
¡ Dietary change
> May also cause acute enteritis (small bowel)
¡ Clostridium perfringens, C. difficile?
¡ Giardia, Whipworms (Trichuris)
¡ Idiopathic (often recurrent)
> Irritable bowel syndrome (IBS)
> “stress-induced colitis”
¡ Acute pancreatitic colitis
ACUTE COLITIS: TREATMENT
- Same decision criteria as with acute vomiting, but hematochezia is not as much of a concern as melena or hematemesis
- Treatment of acute diarrhea: 3 “S”
> Supportive, symptomatic, specific - Fluid therapy
> Fluid losses occur via osmosis, secretion, exudation
> if dog is still drinking and normally hydrated no treatment given - Dietary restriction/change
- Do not routinely use “typical antibiotics [e.g. amoxicillin]” with simple acute diarrhea
- Motility modifiers
- Adsorbents
- Anti-inflammatory agents
- consider deworming if history of colitis without dietary change
what type of dietary change would we recommend for colitis treatment
- “Bland diet” – no spices
- Highly digestible – max number of nutrients absorbed in small intestine
- Absorptive surface disturbed, so want to reduce osmotic effect
- Want to decrease secretion from bacterial action on nutrients
- Proteins with high biological value
- Fats often reduced although highly digestible
- Complex carbohydrates – cooked white rice highly digestible
- Low fibre
- Commercial GI foods
- Home-made: rice, cottage-cheese, boiled chicken
do we usually use antibiotics to treat acute colitis? which ones? why? drawbacks?
¡ Do not routinely use “typical antibiotics [e.g. amoxicillin]” with simple acute diarrhea > Metronidazole or tylosin
- Metronidazole and tylosin have been frequently used in the management of chronic & recurrent idiopathic colitis
> Effect on GI microbial flora (treatment for dysbiosis)
> Effect on specific pathogens (Clostridium spp.)
> Local anti-inflammatory and immunosuppressive effects
> However, can promote dysbiosis and reductions of essential bacteria* - Some animals receive long-term therapy
