GI: 354 - 357

Question 1

What is thought to be the cause of Crohn disease vs. ulcerative colitis?

Answer 1

Crohn disease - disordered response to intestinal bacteria

Ulcerative colitis - autoimmune

Question 2

What is the difference in localization of Crohn disease vs. ulcerative colitis?

Answer 2

Crohn disease - any portion of the GI tract; usually the terminal ileum and colon; skip lesions; rectal sparing

Ulcerative colitis - colonic inflammation that is continuous; always has rectal involvement

Question 3

What do you see on gross morphology with Crohn disease?

Answer 3

Transmural inflammation - fistulas, cobblestone mucosa, creeping fat, bowel wall thickening, linear ulcers, fissures

Question 4

What do you see on barium swallow with Crohn disease?

Answer 4

String sign - due to wall thickening which narrows the lumen

Question 5

How is gross morphology of ulcerative colitis different from Crohn disease in terms of the layers affected?

Answer 5

Ulcerative colitis affects mucosa and submucosa vs. Crohn disease which is transmural

Question 6

Describe what you see on gross morphology with ulcerative colitis.

Answer 6

Friable mucosal pseudopolyps with freely hanging mesentery

Question 7

What do you see on imaging with ulcerative colitis and why?

Answer 7

Lead pipe appearance with loss of haustra

Question 8

Contrast Crohn disease and ulcerative colitis in terms of Th1 vs. Th2 response.

Answer 8

Crohn disease - Th1 (noncaseating granulomas and lymphoid aggregates)

Ulcerative colitis - Th2 (crypt abscesses, ulcers, bleeding, no granulomas)

Question 9

Strictures (leading to obstruction), fistulas, perianal disease, malabsorption, nutritional depletion, colorectal cancer, gallstones - complications of Crohn or ulcerative colitis?

Answer 9

Crohn

Question 10

Malnutrition, sclerosing cholangitis, toxic megacolon, colorectal cancer - complications of Crohn or ulcerative colitis?

Answer 10

Ulcerative colitis

Question 11

When do you have an increased risk of colorectal cancer with ulcerative colitis?

Answer 11

Worse with right-sided colitis or pancolitis

Question 12

Is bloody diarrhea more common with Crohn disease or ulcerative colitis?

Answer 12

Ulcerative colitis

Question 13

Compare and contrast the extraintestinal manifestations of Crohn disease vs. ulcerative colitis.

Answer 13

Both - erythema nodosum, uveitis, aphthous ulcers, ankylosing spondylitis, pyoderma gangrenosum

Crohn only - migratory polyarthritis, kidney stones

Ulcerative colitis only - primary sclerosing cholangitis

Question 14

How do we treat Crohn disease?

Answer 14

Corticosteroids, azathioprine, methotrexate, infliximab, adalimumab

Question 15

How do we treat ulcerative colitis?

Answer 15

ASA preparations (sulfasalazine), 6-mercaptopurine, infliximab, colectomy

Question 16

How do we define irritable bowel syndrome?

Answer 16

Recurrent abdominal pain associated with at least 2 of the following:

1. Pain improves with defecation
2. Change in stool frequency
3. Change in appearance of stool

Question 17

What are the structural abnormalities with irritable bowel syndrome?

Answer 17

None

Question 18

Is irritable bowel syndrome more of an acute or chronic disease?

Answer 18

Chronic

Question 19

What demographic does irritable bowel syndrome tend to affect?

Answer 19

Middle aged women

Question 20

How does IBS tend to present?

Answer 20

Diarrhea, constipation, or alternating symptoms

Question 21

How do we treat IBS?

Answer 21

Symptomatic management

Question 22

Contrast the causes of appendicitis in children vs. adults.

Answer 22

Children - lymphoid hyperplasia

Adults - obstruction by fecalith

Question 23

How does appendicitis present?

Answer 23

Initial diffuse periumbilical pain that migrates to McBurney point

Question 24

Where is McBurney point?

Answer 24

Half the distance between anterior superior iliac spine to umbilicus

Question 25

If an appendicitis patients has fever and nausea, what should you be concerned about?

Answer 25

Possible perforation

Question 26

What might you see with perforation of the appendix?

Answer 26

Psoas, obturator, and Rovsing signs

Question 27

What should be on your differential with appendicitis?

Answer 27

Diverticulitis (elderly), ectopic pregnancy (beta-hCG to rule out)

Question 28

How do you treat appendicitis?

Answer 28

Appendectomy

Question 29

What is the difference between a true vs. false diverticulum?

Answer 29

True diverticulum - all 3 gut wall layers outpouch (e.g. Meckel)