Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

gi > Colon > Flashcards

Colon Flashcards

1
Q

What is pseudomembranous colitis?

A

clinicopathologic diagnosis associated with pseudomembrane formation from necrotic epithelial cells, acute inflammatory cells, and fibrinous material

caused by: C. difficile colitis, ischemic colitis, diversion colitis, idiopathic IBD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the mechanism of pseudomembranous colitis?

A

enterotoxin A –> cell damage, inflammation

Cytotoxin B –> cell death

third toxin –> stimulates colonic motor activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the symptoms of pseudomembranous colitis?

A

diarrhea after taking antibiotics

can be mild/self-limited or chronic

can present as toxic megacolon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the gross pathology of pseudomembranous colitis?

A

discrete, raised, indurated, creamy yellow plaques that attach to GI tissues

affects large bowel almost exclusively

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the microscopic findings of pseudomembranous colitis?

A

well-demarcated disrupted crypts with an overlying pseudomembrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the distribution of ulcerative colitis?

A

begins in rectum and spreads proximally to the whole colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the symptoms of ulcerative colitis?

A

large volumes of watery diarrhea and passage of blood per rectum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the macroscopic features of ulcerative colitis?

A

shortening of colon

oozing of blood, friable mucous membranes

full thickness ulceration that is patchy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the microscopic features of ulcerative colitis?

A

crypt abscess formation with goblet cell depletion

mucosal inflammation that does not extend beyond the submucosal layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the complications of ulcerative colitis?

A

toxic megacolon, perforation, hemorrhage, cancer

systemic: uveitis, arthritis, sclerosing cholangitis, pyoderma gangrenosum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the major types of neoplastic polyps?

A

tubular adenoma

villous adenoma (worse prognosis)

adenoma-carcinoma sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the molecular pathogenesis of familail adenomatous polyposis?

A

autosomal dominant mutation in APC gene (tumor suppressor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the natural history of familial adenomatous polyposis?

A

colon with 100-1000s of polyps that eventually develop into colorectal adenomas within 2-3 decades of life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What dietary factors contribute to adenocarcinoma of colon and rectum?

A

high animal fat diet

low fiber diet

nitroso compounds from grilled meat and fish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the histological findings of adenocarcinoma of colon and rectum?

A

adenocarcinomas with some mucin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What lesions are precancerous for colon/rectal adenocarcinoma?

A

familial polyposis, large adenomas, ulcerative colitis, Chron’s disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is this?

A

normal histology of the colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is this?

A

ulcerative colitis

cryptitis and crypt abscesses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the difference between the distribution of Crohn’s disease and ulcerative colitis?

A

Crohn’s disease: transmural, discontinuous inflammation

ulcerative colitis: continuous ascending inflammation from rectum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the histological differences betwen ulcerative colitis and Crohn’s disease?

A

UC: crypt abscess with mucosal-restricted inflammation

CD: granulomas with transmural inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which IBD is associated with primary sclerosing cholangitis?

A

ulcerative colitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is this?

A

hyperplastic polyp of colon

star-shapped/serration pattern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What genetic mutation is associated with juvenile polyposis?

A

SMAD4 mutation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What type of diverticuli occur in the colon? How do they arise?

A

pseudo-diverticula –> do not include all layers of the colon

herniation of mucosa through the muscularis propria at weak points in the colonic wall (where vasa recta penetrates) caused by abnormal motility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is diverticulitis?

A

inflammation of a diverticulum due to obstruction of the opening, often from a ball of stool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the natural history of diverticulitis?

A

mostly uncomplicated and will resolve with rest +/- antibiotics

may require surgery if abscess, macro perforation, strictures, fistulas form

1/3 recurrent episode after first attack, 1/3 of those will have a third epsode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is diverticular bleeding?

A

painless bleeding from rectum due to segmental weakness of the vasa recta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the risk factors for diverticular bleeding?

A

hypertension, atherosclerosis, NSAID use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is symptomatic colitis with diverticula (SCAD)?

A

inflammation of interdiverticular mucosa without involvement of diverticular orifices

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is symptomatic uncomplicated diverticular disease (SUDD)?

A

persistent pain attributed to diverticula in the absence of overt colitis or diverticulitis, likely due to visceral hypersensitivity

31
Q

What are the two watershed regions of the colon?

A

splenic flexure (Griffith’s point)

rectosigmoid junction (Sudeck’s point)

32
Q

What are the three mechanisms of injury in ischemic colitis?

A

non-occlusive ischemia

embolic or thrombolic arterial occlusion

mesenteric venous occlusion

33
Q

What is the cause of non-occlusive ischemic colitis? What is the damage pattern?

A

cause: cardiac failure, shock, dehydration, vasoconstrictive drugs

chronic disease process, leads to damage limited to muscularis mucosa (not transmural)

34
Q

What are causes of embolic/thrombotic arterial occlusive ischemic colitis? What is the pattern of damage?

A

causes: emboli, aortic instrumentation, vasculitis, atherosclerosis, aortic aneurysms, hypercoaguable states

transmural infarction

35
Q

What is the clinical presentation of ischemic colitis?

A

sudden onset cramping and tenderness over affected bowel with mild to moderate rectal bleeding

36
Q

What is this?

A

lymphocytic colitis

intraepithelial lymphocyte infiltration in colon, > 20 per high powered field

37
Q

What is this?

A

collagenous colitis

colonic subepithelial collagen band

38
Q

What are the two major types of microscopic colitis?

A

lymphocytic colitis

collagenous colitis

39
Q

What are major causes/associations with microscopic colitis?

A

middle-aged or older women

autoimmune diseases

triggers: NSAIDs, PPIs, ranitidine, sertraline, smoking

40
Q

What is the clinical presentation of microscopic colitis?

A

chronic watery diarrhea, normal labs, normal colonoscopy (need biopsy)

41
Q

How is microscopic colitis diagnosed?

A

requires biopsy and histologic diagnosis

42
Q

Why are diverticuli most common in the sigmoid colon?

A

it has the smallest diameter and is thus under the highest pressure, predisposing it to diverticula formation

43
Q

Which of the following should be recommended to a patient after their first episode of diverticulitis?

a) avoidance of nuts and seeds
b) surgery to prevent recurrence
c) colonoscopy in 2-4 weeks
d) CT scan in 4 weeks to ensure resolution of inflammation
e) high fiber diet

A

c) colonoscopy in 2-4 weeks

44
Q

A 65 yo male with a history of coronary artery disease presents with sudden onset abdominal pain, urgency, and diarrhea following a syncopal episode at home. He subsequently develops bloody diarrhea and is admitted to the hospital. He has never had a colonoscopy. Which of the following is the most likely cause of his bleeding:

a) diverticular bleeding
b) microscopic colitis
c) ischemic colitis
d) colon cancer
e) hemorrhoids

A

a) diverticular bleeding

45
Q

Which of the following is true regarding microscopic colitis:

a) it is predominantly seen in young, male patients
b) abdominal pain is a common symptom
c) ranitidine is implicated as a possible trigger
d) presence of > 10 intraepithelial lymphocytes per high power field is diagnostic of lymphocytic colitis

A

c) ranitidine is implicated as a possible trigger

  • A is not true bc it is more common in older women*
  • B is not true because it presents with chronic, watery diarrhea*
  • D is not true because it requires > 20 for diagnosis*
46
Q

Which IBD does this describe: colon involvement only

A

ulcerative colitis

Crohn’s disease involves any part of GI tract

47
Q

Which IBD does this describe: focal, skip lesions

A

Crohn’s disease

Ulcerative colitis is diffuse, contiguous

48
Q

Which IBD does this describe: transmural involvement with granulomas

A

Crohn’s disease

ulcerative colitis has only superficial inflammation

49
Q

What are the clinical GI symptoms of IBD?

A

depends on which part of GI tract is involved

diarrhea, blood in stool, abdominal pain/cramping, rectal pain, weight loss, nausea/vomiting, failure to thrive in infants

50
Q

What are the extraintestinal symptoms of IBD?

A

joint/bone involvement: ankylosing spondylitis, metabolic bone disease

skin: pyoderma gangrenosum, erythema nodosum, apthous ulcers
ocular: episcleritis, uveitis
hepatobiliary: primary sclerosing cholangitis (ulcerative colitis), cholelithiasis, autoimmune hepatitis
renal: kidney stones

51
Q

What is the treatment for IBDs?

A

5-ASA

antibiotics

steroids

immunomodulators

anti-TNF and anti-adhesion molecule biologics

surgery

52
Q

A 20 yo male who quit smoking 2 months ago presents with intermittent bright red blood per rectum. He has no abdominal pain, constipation, or diarrhea. He does note some fecal urgency and mucous discharge. His symptoms have been ongoing for 6 months. Physical exam unremarkable, labs unremarkable except slight anemia (low Hgb). What should be done next for evaluation?

a) endoscopic evaluation
b) abdominal CT scan
c) stool culture
d) trial of OTC hemorrhoid medication

A

a) endoscopic evaluation

53
Q

A 20 yo female with Crohn’s disease presents with severe right flank pain and is found to have kidney stones. She most likely has Crohn’s disease of the:

a) colon
b) esophagus
c) stomach
d) ileum

A

d) ileum

54
Q

Which of the following are extraintestinal manifestations of IBD:

a) episcleritis
b) cervical lymphadenopathy
c) oral apthous ulcers
d) erythema nodosum
e) sacroileitis
f) pyoderma gangrenosum
g) nephrolithiasis
h) osteoarthritis
i) primary sclerosing cholangitis
j) gallstones

A

a) episcleritis
c) oral apthous ulcers
d) erythema nodosum
e) sacroileitis
f) pyoderma gangrenosum
g) nephrolithiasis
i) primary sclerosing cholangitis
j) gallstones

B and H are not associated with IBD

55
Q

The diagnosis of IBD is made by:

a) histology
b) endoscopy
c) radiology
d) clinical history
e) all of the above

A

e) all of the above

56
Q

An 18 yo female presents with abdominal pain and bloody diarrhea after returning from a trip to mexico. She was empirically givencirpofloxacin by her PCP without benefit. It has now been 6 weeks after her return and she still has 3-4 bowel movements daily with blood and slight abdominal cramping with bowel movements. She has a colonoscopy and there is diffuse, continuous inflammation, granular appearing mucosa starting in rectum up to splenic flexure. The colon proximal to this and the ileum appears normal. What is the most likely diagnosis?

a) Crohn’s disease
b) ulcerative colitis
c) infectious colitis
d) irritable bowel syndrome

A

b) ulcerative colitis

57
Q

What are risk factors for colorectal cancer?

A

high fiber consumption, obesity

possibly also: diabetes, cholecystectomy, eating red meats, smoking, alcohol, radiation

58
Q

What are protective factors for colorectal cancer?

A

high fiber consumption, physical activity, low BMI, NSAIDs

possibly also: calcium, magnesium, HRT, statins

59
Q

What is the relationship of genetic factors in colorectal cancer?

A

most are sporadic not familial, but in familial cases and syndromes there is a large risk

60
Q

What types of polyps increase risk of colorectal cancer?

A

large, adenomatous polyps

multiple polyps

polyps with villous features

61
Q

What is the relationship between IBD and colorectal cancer?

A

ulcerative colitis increases risk of colorectal cancer

62
Q

What is the adenoma-carcinoma sequence?

A

APC mutation for FAP or mismatch repair mutations for Lynch syndrome (initial mutation)

K-Ras mutations and DCC mutations contribute to carcinogenesis

63
Q

What are the symptoms of colorectal cancer?

A

abdominal pain/rectal pain, change in bowel movement patterns, hematochezia, anemia, weight loss/fatigue, symptoms of metastatic disease (liver, lung, lymph nodes, peritoneum)

64
Q

What is the best screening method for colorectal cancer?

A

colonoscopy

65
Q

What is the TNM system of cancer staging?

A

T = depth of tumor invasion

N = lymph node involvement

M = metastases

66
Q

How is colorectal cancer treated?

A

mostly with surgery if it is possible to remove the whole lesion

can also involve chemotherapy, radiation, andpalliation of symptoms

67
Q

What are all of the screening methods for colorectal cancer?

A

fecal occult blood test –> low cost, easy to use, but lower sensitivity

Fecal DNA

Combo fecal blood and DNA

Flexible sigmoidoscopy

colonoscopy

CT colonography

capsule colonoscopy

68
Q

When should patients be screened for colorectal cancer?

A

without family history or history of polyps/cancer: start at 45 or 50 and screen every 10 years until age 75

with family history in person under 60: start 10 years before they were diagnosed (or at age 40) and screen every 5 years

with family history in person 60+: start at 40 and, if negative, continue with general 10 year screening pattern

with history of IBD: colonoscopy every 1-2 years

69
Q

How should patients with FAP be screened for colorectal cancer?

A

genetic testing

annual endoscopic screening

colectomy for patients with the genetic mutation + polyps

70
Q

How should patients with Lynch syndrome be screened for colorectal cancer?

A

genetic counseling

colonoscopy starting at age 20-25 every 1-2 years

71
Q

With respect to the epidemiology and risk factors, which of the following is correct?

a) the incidence of colorectal cancer is generally lower in more developed countries
b) in the US, colorectal cancer is the most common gastrointestinal cancer
c) a diet high in fiber has been associated with a higher risk of colorectal cancer
d) obesity has been associated with lower risk of colorectal cancer

A

b) in the US, colorectal cancer is the most common gastrointestinal cancer

72
Q

A 55 yo man had a screening colonoscopy, revealing 3 adenomatous polyps which were completely removed. With respect to pathogenesis, familial risk, and need for future follow up, which is the most appropriate recommendation:

a) no further evaluation required in the future, since the polyps were all removed
b) this patient’s 2 brothers, ages 51 and 53, are not at increased risk and do not need to be screened for colorectal cancer
c) he should have genetic testing performed now, as most colorectal polyps are found in individuals with genetic syndromes
d) he should undergo surveillance colonoscopy at the interval recommended by his physician
d) he should undergo surveillance colonoscopy at the interval recommended by his physician

A

d) he should undergo surveillance colonoscopy at the interval recommended by his physician

73
Q

A 49 yo man is at his PCP for an annual visit, with no other complaints except fatigue, which he attributes to a busy work schedule. His exam is normal except for pale skin and conjunctivae. Blood work reveals a new moderate microcytic anemia, with iron indices consistent with iron deficiency. He has no family history of colorectal cancer or polyps. What would you suggest next?

a) iron supplementation and recheck hemoglobin and iron studies in 3 months
b) reduce work hours, get more test, and when he turns 50 should have colorectal cancer screening
c) referral to gastroenterologist for evaluation, including colonoscopy
d) emergent admission to the hospital for blood transfusion

A

c) referral to gastroenterologist for evaluation, including colonoscopy

74
Q

A 51 yo woman presents to her PCP for her annual visit. She feels well and has no family history of colorectal cancer. She wants to know if she is at risk for colorectal cancer and what she can do to prevent it or reduce her risk of dying of this disease. What would be the appropriate recommendation?

a) since she has no family history of colorectal cancer her risk is very low, so she should not worry about it
b) she should consider screening for colorectal cancer now since she is over 50 and has no family history
c) she should consider genetic testing; if negative, she’s not at risk for colorectal cancer
d) she does not have to worry about it, since colon cancer is much less common in women

A

b) she should consider screening for colorectal cancer now since she is over 50 and has no family history

gi (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions