Diarrhea

If secretion and intake outweighs absorption what will we see?

Diarrhea

If absorption outweighs secretion and intake what will we see?

Constipation

What is diarrhea characterized by?

Increased fluidity, frequency or volume of feces

What characteristics will diarrhea have?

Decreased consistency/ liquified

Higher h20, electrolytes, or fat content

Increased BM

What is osmotic diarrhea?

Presence of poorly absorbable, low moleculary weight osmotically active substances leading to a high osmolarity in the lumen resulting in retained water

What are some hyperosmotic cathartics?

Sugar alcohols

Mg or Na

Polyethylene glycol

Hydrophilic colloids (methylcellulose)

What is salt toxicity? How can it be prevented?

Caused by water deprivation, or excess salt intake.

Causes dehydration via water loss (diarrhea)

unlimited water access (animals can adapt to new sodium diets in few days)

What can cause maldigestion?

Inflammatory dz that limits absorption due to loss of enzymes on the membrane.

What is the digestion process needed for?

Break down polymers to monomers because only simple molecules can be absorbed

Maldigestion refers to?

Not digested enough and will lead to Malabsorption

Malabsorption is due to to?

Intestinal epithelial damage

What is EPI (endocrine pancreatic insufficiency)

Insufficient production of digestive enzymes by the pancreas acinar cells leading to incomplete digestion of starches, proteins and fats

What is a lactose intolerance? When is it most common in animals?

Lactose needs to be hydrolyzed by lactase and if absent it will be retained and drag water with it causing diarrhea

more common in dogs/cats and can occur post weaning

What is lymphangiectasia?

When the lacteal structure is dilated/dysfunctional or obstructed

improper absorption of fats and leaking of protein rich lymph resulting in diarrhea

Lymphangiectasia is a ____ dz?

Congenital dz

What things can Lymphangiectasia cause? Why?

Diarrhea, Steatorrhea, Lymphopenia, Hypoproteinemia, Hypochlorestorolemia

from malabsorption of lipids and loss of plasma proteins

What can occur due to the hypoprotienemia that Lymphopenia causes?

Ascites and hydrothorax

When does secretary Diarrhea occur?

Excessive/ uncontrolled secretion surpasses absorptive capacity of the intestines

What mediates secretory diarrhea and what can have an effect on this?

Cl- secretion

Affected by bacterial toxins, fat malabsorption, bile acids

Nutrition absorption will be _____ w/ secretory diarrhea?

Normal

Secretory diarrhea is unaffected by what? Why?

Fasting

toxin ingesta do not depend on presence of digesta

How do oral rehydration solutions work? What might have added advantages?

Will increase Na/Glucose transporter resulting in water being absorbed

glutamine may be better over glucose

What does hypergastrinemia cause?

Due to high levels of gastrin in the system parietal cells increase HCl secretion and will lead to ulcers and diarrhea

What can be causes of hypergastrinemia?

Intestinal resections

Cessation after longer antacid usages

Zollinger Ellison syndrom (gastrinoma)

How does Cholera impact Cl- transport?

releases toxin that activates G protein and produces cAMP

cAMP activates Cl- channel CFTR and exacerbates Cl- secretion causing diarrhea from Na/H2O coupled paracellular secretion

How does E. coli affect Cl- transport?

produces heat labile toxin that acts like cholera toxin but less potent

heat-stable toxins activate guanylate cyclase that activates CFTR and blocks NHE via cGMP

exacerbates Cl- secretion and Na/H2O follow via paracellular secretion

What are the direct and indirect effects of gastrin?

direct - stimulate H+ secretion from parietal cell

indirect - stimulate histamine release from ECL cell (along w Ach)

What are the signs and dx for hypergastrinemia?

anorexia, hematemesis, intermittent diarrhea, melena

dx via gastrin blood levels