Large bowel

Question 0

Sx of diverticulosis

Answer 0

Often asymptomatic
Presents with sudden, intermittent, painless bleeding. Often times presents with symptoms of anemia (fatigue, lightheadedness, dyspnea on exertion)

Question 1

Definition of diverticula

Answer 1

Outpouchings of mucosa and submucosa that herniate through the colonic muscle layers.
Occurs in areas of high intraluminal pressure
Usually in the sigmoid colon

Question 2

Diverticulitis and imaging

Answer 2

Avoid sigmoidoscopy and colonoscopy in early stages due to increased risk of perforation

Question 3

Tx of diverticular dz:

-uncomplicated diverticulosis, diverticular bleeding, diverticulitis

Answer 3

Diverticulosis: encourage high-fiber diet. routine follow up
Diverticular bleeding: usually stops spontaneously; transfuse and hydrate as needed; if bleeding doesn’t stop then hemostasis w/ colonoscopy, angiography + embolization, or surgery
Diverticulitis: NPO, IVF, antibiotics (metro + fluoroquinolone or ceftriaxone)
Perforation: surgery with resection and Hartmann pouch formation

Question 4

Etiologies of large bowel obstruction

Answer 4

Colon cancer, diverticulitis, volvulus, fecal impaction

Question 5

Presentation of SBO vs LBO

Answer 5

SBO: nausea, vomiting, abdominal distention, moderate-severe acute abdominal pain, hyperactive bowel sounds
LBO: constipation, distention, abdominal pain less intense than SBO, hyperactive bowel sounds

Question 6

Dx of large bowel obstruction

Answer 6

CT
Water contrast enema if perforation is susepcted
Colonoscopy/sigmoidoscopy if stable

Question 7

Tx of large bowel obstruction

Answer 7

Obstruction can be relieved with a Gastrograffin enema, colonoscopy, or a rectal tube
Surgery is usually required
Ischemic colon usually requires partial colectomy with a diverting colostomy

Question 8

Which polyps are more likely to become colorectal cancer?

Answer 8

Villous > tubular

Sessile > pedunculated

Question 9

Colorectal cancer screening recommendations:

-no risk factors, first degree relative w/ colon cancer, ulcerative colitis

Answer 9

No risk facts:

• start screening at age 50
• stool guaiac and DRE annually + EITHER colonoscopy q10 years or sigmoidoscopy q5 years

First-degree relative with colon cancer

• Colonoscopy q10 years starting at age 40 OR
• Colonoscopy q10 years starting 10 years prior to the age of the affected family member at time of diagnosis. Whichever comes first

Ulcerative colitis:
-colonoscopy every 1-2 years starting 8-10 years after diagnosis

Question 10

Right sided vs. left sided colon cancer presentation

Answer 10

Right sided: bulky, ulcerating mass that leads to anemia from chronic occult blood loss;

Left sided: apple-core obstructing masses; patients complain of change in bowel habits (ie decreased stool caliber, constipation) and or blood-streaked stools

Rectal lesions: p/w bright red blood per rectum, often with tenesmus and/or rectal pain
-rule out rectal cancer

Question 11

Strep bovis

Answer 11

Cause of endocarditis found in patients with colon cancer

Question 12

Ischemic colitis presentation

Answer 12

Crampy lower abdominal pain and bloody diarrhea

CT with contrast: thickened bowel wall
Colonoscopy: pale mucosa with petechial bleeding