GI 10

Question 1

5 Steps in Sequence of Vomiting

Answer 1

1. Reverse peristalsis in small intestine
2. Relaxation of stomach and pylorus
3. Forced inspiration to increase abdominal pressure
4. Relaxation of LES and forceful expulsion of contents
5. Relaxation of UES

Question 2

What steps in vomiting constitute retching?

Answer 2

steps 1 through 4

Question 3

Diarrhea

Answer 3

an increase in the frequency of defectation or fecal volume

Question 4

4 Types/Causes of Diarrhea

Answer 4

1. Osmotic Diarrhea
2. Secretory Diarrhea
3. Infectious Diarrhea
4. Increased Motility

Question 5

Most common type of diarrhea seen in practice?

Answer 5

osmotic diarrhea

Question 6

Overall cause of osmotic diarrhea?

Answer 6

maldigestion and malabsorption

Question 7

Osmotic Diarrhea

Answer 7

essentially a high concentration of undigested solutes remain in the GI tract therefore the gradient keeps water within the lumne rather than being absorbed

Question 8

5 Possible Causes of Osmotic Diarrhea

Answer 8

1. Digestive enzme deficiencies
2. Bile salt malabsorption
3. Ingestion of unabsorbable solute
4. Decreased epithelial surface area
5. Genetic mutation affecting SGLT-1 (sodium transporter)

Question 9

Simplest way to stop osmotic diarrhea?

Answer 9

remove the causing agent (can also treat with osmotic laxatives)

Question 10

2 Causes of Secretory Diarrhea

Answer 10

1. Increased [chloride] secretion
2. Reduction in electrolyte absorption

Question 11

Relation bewteen chloride and secretion

Answer 11

more chloride in lumen = more secretions

Question 12

Normal Mechanism of Chloride Secretion

Answer 12

simply put, increase in intracellular protein kinase activity phosphoylates and widens the opening of CFTR channels increasing Cl- secretion

Question 13

Pathogens that can cause uncontrolled chloride secretion (3)

Answer 13

1. E. coli
2. Vibrio cholerae
3. C. diff

Question 14

Why do toxins cause uncontrolled chloride secretion?

Answer 14

There’s not a feedback loop, the body doesn’t respond to decrease the amount - toxins will keep producing toxins, Cl- is continuously released (and can also inhibit sodium absorption via its exchanger)

Question 15

Premise of Rehydration Therapy for Secretory Diarrhea

Answer 15

toxins block your Na+/H+ and Bicarbonate/Cl- exchangers, but your sodium cotransporters still function –> give sugars or AAs to get sodium in the cell, and chloride absorption (passive) will follow

Question 16

Congenital Chloride Diarrhea

Answer 16

genetic mutation of Bicarbonate/Cl- exchanger –> defective absorption of Cl-

Question 17

Will secretory diarrhea stop if you withhold food?

Answer 17

NO, it will continue

Question 18

2 Types of Infectious Diarrhea

Answer 18

1. Inflammatory
2. Noninflammatory

Question 19

3 Types of Infectious Agents

Answer 19

1. Bacteria
2. Viruses
3. Parasites

Question 20

Most common cause of secretory diarrhea?

Answer 20

cholera toxin (technically infectious)

Question 21

How do infectious agents cause diarrhea? (2)

Answer 21

1. Modulate epithelial ion transport
2. Disrupt epithelial barrier function

Question 22

Non-Inflammatory Diarrhea Symptoms

Answer 22

negative fecal leukocytes, watery/large volume, no blood, no fever

Question 23

Inflammatory Diarrhea Symptoms

Answer 23

positive fecal leukocytes, mucoid/small volume, bloody, fever

Question 24

Type of Diarrhea caused by motility issues?

Answer 24

Irritable Bowel Syndrome (increases peristaltic contractions, increased motility, not enough time for segmentation to absorb)