Approach to Diarrhea - Stein

Question 1

What is the definition of diarrhea?

Answer 1

>200 grams of stool or 200mL of stool in a 24 hour period

However, a high-fiber diet can easily produce more than 300g

Question 2

What are the two varieties of diarrhea?

Answer 2

Malabsorptive vs Exudative

Question 3

Which type of diarrhea fits the following description?

1. Etiology is inflammation
2. Relieved by fasting
3. Due to nutrient absorption problems
4. Bloody Stools
5. Watery Stools
6. Continues during fasting

Answer 3

1. Exudative
2. Malabsorptive
3. Malabsorptive
4. Exudative
5. Malabsorptive
6. Exudative

Question 4

What can cause malabsorptive diarrhea?

Answer 4

1. Failure of intraluminal digestion
2. Failure of terminal digestion
3. Failure of transepithelial transport
4. Failure of lymphatics transport

Question 5

What is a “normal” amount of bowel movements?

What is diarrhea?

Answer 5

Patient’s baseline; ranges from 1x every 3 days to 3x/day

More than 3 watery/loose stools per day OR a clear increase in the baseline

Question 6

What clues on history can indicate real diarrhea?

Answer 6

• Consistency
• Urgency
• Incontinence
• Nocturnal BMs
• Flatuphobia

Question 7

What volume of fluid enters the stomach each day?

What volume is eliminated in the stool?

Where is water absorbed?

Answer 7

10L

0.1 L

6L in the jejunum

2. 5L in the ileum
3. 4L in the colon

Question 8

What are some indications that the diarrhea is caused by problems in the small intestine?

Answer 8

• Large, infrequent, watery stools
• Cramping, bloating, gas
• Fever unlikely
• Blood or WBC in stool unlikely

Question 9

What are some indications that the diarrhea is caused by problems in the large bowel?

Answer 9

• Frequent, small stools
• Tenesmus (rectal dry heaving)
• Painful BM
• Bloody, mucus-y stools
• WBCs in stool common

Question 10

What is osmotic diarrhea?

What is the cause?

Answer 10

Watery, loose stools

Caused by a problem absorbing nutrients in the intestines; the intestines can not maintain an osmotic gradient

Mannitol, sorbitol

disaccharide deficiency

magnesium, phosphate, sulfate

Question 11

What is secretory diarrhea?

What causes it?

How can secretory diarrhea be distinguished from osmotic diarrhea?

Answer 11

water loose stool

excretion of chloride or blocked sodium absorbtion, typically caused by infection or enterotoxins

Electrolyte profile and osmotic gap will be different.

Question 12

What are the most likely causes of acute diarrhea?

What are the most likely causes of chronic diarrhea?

Answer 12

Infections, Food poisoning, Medications

Food allergies, Autoimmune, Anatomic problems, Cancer

Question 13

What should you do when a patient comes in complaining of diarrhea?

Answer 13

• Assess fluid state
• Try to determine consistency/frequency
• Ask about associated symptoms:
  
  • Tenesmus
  • Abdominal pain
  • Nocturnal Waking
  • Blood in stool
  • Incontinence
  • Flatuphobia
• Ask about recent travel
• Changes in diet, medications

Question 14

What are the most likely causes of diarrhea with fever?

Answer 14

• Invasive Bacteria
• Enteric Viruses
• Ischemia
• IBD

Question 15

What things should you look for on physical exam when a patient comes in with diarrhea?

Answer 15

• Diabetic Herpetiformis
  
  • Celiac Disease
• Erythema Nodosum
  
  • IBD
• Arthritis
  
  • IBD
• Fistulas
  
  • Crohn’s Disease
• Abdominal Mass
  
  • Cancer

Question 16

How sensitive are the tests for cryptosporidium and giardia?

How specific are the tests?

Answer 16

90%

almost 100%