5. Epidemiology …
- According to ( WHO ) there are more than 700 million episodes of
diarrhea annuallyin children 5 years of age in developing countries.
- more than two to four weeks occurs in up to 3 to 5 percent of the
population worldwide.
- more frequent in men.
10. Osmotic diarrhea
It’s caused by the presence of nonabsorbable solutes in the
gastrointestinal tract.
e.g. lactose intolerance
11. Secretory diarrhea …
Activation of intracellular mediators (cAMP, cGMP and intracellular
calcium)
This stimulates active chloride secretions from the crypt and prevent
the neutral coupled sodium chloride absorption.
Thus the intraluminal electrolyte content will be high and this leads to
diarrhea.
e.g. cholrea, E.coli.
12. Mutations in apical membrane
transport proteins …
Congenital defects in:
1.
Sodium-hydrogen exchange.
2.
Chloride-bicarbonate exchange.
3.
And sodium-bile acid transport protein
13. CON’T …
Reduction in anatomic surface area:
This is called short bowel syndrome and can occur after surgical
indications.
And alteration in intestinal motility:
This can result duo to malnutrition, scleroderma, and diabetes mellitus.
14. Causes …
1- Noninfectious Causes of Chronic Diarrhea :
A. Antibiotic Therapy
B. Extraintestinal Infections
C. Malnutrition
D. Diet and Medications
E. Allergic Diarrhea
F. Chronic Nonspecific Diarrhea
G. Secretory Diarrhea
H.Inflammatory bowel disease
15. CON’T …
2- Infectious Causes of Chronic Diarrhea:
e.g. salmonella, Giardia lamblia
common in immune deficiency
states, especially IgA deficiency and T-cell abnormalities.
