Pathophysiology of Diarrhea & Malabsorption

Question 1

Sudden-onset diarrhea with abdominal cramps and fever point to what cause?

Answer 1

Infectious

Question 2

How is lactose intolerance diagnosed?

Answer 2

Clinically - confirmed by a hydrogen breath test or lactose tolerance test

Question 3

True/False. Patients with chronic diarrhea always require medical evaluation.

Answer 3

True

Question 4

This type of diarrhea generally improves with fasting.

Answer 4

Malabsorptive diarrhea

Question 5

What are the different mechanisms of diarrhea?

Answer 5

Osmotic, secretory, malabsorptive, exudative

Question 6

True/False. Acute diarrhea lasts less than 7 days.

Answer 6

False - acute diarrhea lasts less than 14 days

Question 7

What HLA are associated with Celiac disease?

Answer 7

HLA-DQ2 & HLA-DQ8

Question 8

This mechanism of diarrhea is due to the retention of unabsorbable solutes in the gut.

Answer 8

Osmotic diarrhea

Question 9

What is the clinical presentation of abetalipoproteinemia?

Answer 9

During infancy - failure to thrive, malabsorption, fat-soluble vitamin deficiency, steatorrhea

Question 10

Tropical sprue is an enteropathy associated with tropical areas. What is the treatment?

Answer 10

Folic acid, tetracycline

Question 11

Lactose intolerance produces what type of diarrhea?

Answer 11

Osmotic diarrhea

Question 12

Patients with Celiac disease are at an increased risk of developing what cancers?

Answer 12

T-cell lymphoma, small bowel adenocarcinoma, esophageal cancer

Question 13

Dermatitis herpetiformis is most associated with what disorder?

Answer 13

Celiac disease

Question 14

Antibiotics are rarely given in cases of acute diarrhea, unless there is compelling evidence to suggest infectious origin. What is the primary focus for treatment of acute diarrhea?

Answer 14

Volume repletion

Question 15

What are the most common bacterial causes of diarrhea in the USA?

Answer 15

Salmonella, Campylobacter, Shigella, STEC

Question 16

What is the most common clinical presentation of malabsorption?

Answer 16

Steatorrhea

Question 17

What is the most common cause of chronic diarrhea?

Answer 17

Irritable bowel syndrome

Question 18

Irritable bowel syndrome is a diagnosis of exclusion. What symptoms characterize the disorder?

Answer 18

Chronic, relapsing abdominal pain, changes in bowel habits (constipation or diarrhea), and abdominal bloating

Question 19

Malabsorption syndrome occurs due to a disturbance in at least one of the four phases of nutrient absorption. What are the four phases?

Answer 19

Intraluminal digestion, membrane digestion, transepithelial transport, lymphatic transport

Question 20

Blood-stained stools generally point to what cause of diarrhea?

Answer 20

Inflammatory

Question 21

What characteristic is a hallmark of malabsorptive-related diarrhea?

Answer 21

Steatorrhea

Question 22

How does dysmotility cause diarrhea?

Answer 22

Increases the transit time and reduced contact time of stool with surface mucosa for absorption

Question 23

What is the treatment for Celiac disease?

Answer 23

Gluten-free diet

Question 24

This mechanism of diarrhea is due to the excessive secretion of electrolytes and water into the gut, with decreased fluid absorption.

Answer 24

Secretory diarrhea

Question 25

Mutations of the microsomal triglyceride transfer protein (MTTP) are associated with what disorder?

Answer 25

Abetalipoproteinemia

Question 26

This mechanism of diarrhea is due to mucosal inflammation or ulceration with destruction of enterocytes and passage of purulent, bloody stool.

Answer 26

Exudative diarrhea

Question 27

When does IBS most commonly present?

Answer 27

Teens and 20s

Question 28

Bile acid diarrhea occurs due to a failure to reabsorb bile acids. Where does this reabsorption take place?

Answer 28

Terminal ileum

Question 29

Pale stools that float are associated with what cause?

Answer 29

Malabsorption with steatorrhea

Question 30

What non-pharmacological treatment is recommended for IBS?

Answer 30

Regular physical activity, diet high in fiber

Question 31

What drugs may be used to treat IBS?

Answer 31

Anticholinergics, serotonin modulators and agonists, loperamide, TCAs

Question 32

What histopathology findings are associated with Celiac disease?

Answer 32

Villous atrophy, cuboidal enterocytes, crypt hyperplasia, plasma cells

Question 33

What is the common clinical presentation of Whipple’s Disease?

Answer 33

Diarrhea, malabsorption, weight loss in a man of 30-40yo

Question 34

How long must diarrhea persist to be classified as chronic?

Answer 34

More than 30 days

Question 35

What are potential complications of diarrhea?

Answer 35

Dehydration, hypovolemic shock, electrolyte imbalances, malabsorption, metabolic acidosis, hypokalemia

Question 36

How does diarrhea due to disease of the small and large intestines differ?

Answer 36

Small intestine disease - Voluminous stools that are watery or fatty, bloating, mid-abdominal pain

Large intestine disease - Small-volume, frequent stools that may be bloody or mucoid, lower abdominal pain

Question 37

What is the treatment for Whipple’s Disease?

Answer 37

Streptomycin or Penicillin & ceftriaxone, followed by one year of trimethoprim/sulfamethoxazole

Question 38

What are the general causes of chronic diarrhea?

Answer 38

Diseases of the small intestine and colon, malabsorption, IBD

Question 39

What is the gold standard for diagnosis of celiac disease?

Answer 39

Duodenal biopsy

Question 40

What is the most sensitive test for diagnosis of Celiac disease?

Answer 40

IgA antibodies against tissue transglutaminase

Question 41

Inflammatory bowel disease causes what type of diarrhea?

Answer 41

Exudative diarrhea

Question 42

Enterocytes laden with lipid-filled vacuoles and acanthocytes are diagnositc of what disorder?

Answer 42

Abetalipoproteinemia