Gastroenteritis

Question 1

Know the 3 major forms (osmotic, secretory and motility) as well as the other classifications of diarrhea (Cecil’s - Table 34-6: page 397) - be able to give examples of each.

Answer 1

Secretory- Increased secretion or decreased absorption of
Na+ and Cl (ex: Cholera)

Osmotic- Non-absorbable molecules in gut lumen (ex: Lactose intolerance)

Motility- Increased motility with decreased time for
absorption of electrolytes or nutrients. Decreased motility with bacterial overgrowth (ex: IBS, scleroderma)

Question 2

Know what questions to ask a patient with a history of diarrhea (page 398-399)

Answer 2

Questions: durations, blood, volume, current meds, nutritional intake, source of water, family hx (celiac sprue, IBD etc)

Question 3

What are the possible causes for chronic diarrhea (Figure 34-7)?

Answer 3

Lactose intolerance, celiac sprue, meds, IBD, IBS, DM, allergies, microscopic colitis

Question 4

Which of the bacteria that we discussed in class have a preformed toxin associated with them and can produce symptoms in the shortest time interval?

Answer 4

Preformed toxins – B. cereus, C. perfringens, S. aureus

Question 5

Know the risk factors for Giardiasis and C. difficile colitis.

Answer 5

Drinking unpurified water or antibiotic use

Question 6

What antibiotics would be used for each (first line and second line for C. diff)?

Answer 6

First line is Metronidazole (Flagyl) and second line is Vancomycin.

Question 7

Infectious Diarrhea is defined as….

Answer 7

increased volume and liquidity of stool.

Question 8

Types of diarrhea include:

Answer 8

Secretory: E. coli toxin, Salmonella, Clostridium perfringens toxin
Osmotic: lactose deficiency, laxatives

Question 9

How do we differentiate secretory vs osmotic diarrhea?

Answer 9

fasting; diarrhea will stop in osmotic

Question 10

The osmotic gap is higher in which type of diarrhea?

Answer 10

Osmotic

Question 11

Which organism produces diarrhea via fecal contamination of food and water? How is it treated?

Answer 11

E. Coli (Not 0157:H7); TMP-SMX or Pepto-Bismol

Question 12

Which organism produces diarrhea via contaminated water or milk? How is it treated?

Answer 12

Campylobacter; no treatment- self-limited & short duration

Question 13

Which organism produces diarrhea via contaminate eggs or milk? How does it present?

Answer 13

Salmonella; Acute, self-limited with crampy abd pain

Question 14

Which organism produces diarrhea via spreading the fecal/oral route? How is it treated and how does it present?

Answer 14

Shingella

Treated with Ampicillin or TMP-SMX

Spread via Day cares and presents as bloody diarrhea

Question 15

Which organism produces diarrhea via the fecal contamination of water only? How is it treated?

Answer 15

Giardia, Treated with metronidazole

Question 16

Which causative agent transmits diarrhea via person to person contact?

Answer 16

Norwalk agent/ Rotavirus