7.2: IBD Flashcards

1
Q

What are the two main types of IBD? Which is more common?

Name four other types of IBD with other causes

A
  1. Ulcerative colitis - slightly more common
  2. Crohn’s disease
    But there are other causes of colitis such as drugs, ischemic colitis, radiation colitis (side effect from radiotherapy), infectious colitis (e.g; Shigella, etc)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe any significant epidemiology findings that put certain individuals at risk for IBD in the following categories; race, age, geography, smoking and genetics

A
  1. Race; 3X more likely if your white in the US
  2. Age; peaks between 20-30 and 50-60
  3. Geography; common in developed countries
  4. Smoking; 4X more likely for crohn’s
  5. Genetics; HLA B27 is the antigen associated with ulcerative colitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is one unique unexplainable thing that lessens your chances of getting IBD? Interestingly, what condition might crohn’s mimic?

A

No appendix! But the clinical presentation of crohn’s may mimic appendicitis

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

What are the three main causes of IBD?

A
  1. Environmental triggers
  2. Genetic susceptibility
  3. Immune dysregulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Name 5 triggers for IBD

A
  1. Stress; causes an altered autoimmune response
  2. Smoking
  3. Diet
  4. Drugs; Antibiotics and NSAIDs
  5. Acute infections
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define Crohn’s Disease

A

Chronic relapsing and remitting inflammatory disease of the digestive tract

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

Name (and describe if necessary) 4 characteristics of Crohn’s

A
  1. Focal; targeted area of the bowel
  2. Asymmetrical; no pattern, sporadic throughout the bowel
  3. Transmural involvement of the bowel wall
  4. Chronic inflammatory process with non-caseating granulomas (no necrotic material)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which part of the GI tract is usually affected by granulomatous inflammation in Crohn’s?

A

Frequently affects the terminal ileum but can affect any part of the GI tract

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

Which absorption process will be hindered in a patient with classic crohn’s?

A

Vit B12 absorption, as granulomatous inflammation in crohn’s commonly affects the terminal ileum

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

Name four things you might see macroscopically in the GI tract in Crohn’s disease

A
  1. Cobblestoning
  2. Bleeding
  3. Fistulas (links between bowel and outside world), and can cause abscesses and infection
  4. Ulceration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Name two major histological changes would you notice in Crohn’s disease

A
  1. Large epitheloid granulomas

2. Multinucleated giant cells

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

Describe the association with autoimmune disease and autoantibody production for Crohn’s and Ulcerative colitis

A

Crohn’s; weak association with autoimmune diseases and rarely associated with autoantibody production (like an anti colon antibody, etc)

Ulcerative colitis: strong association with autoimmune diseases and commonly associated with autoantibody production

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

Describe the T cell reactivity, type of granuloma (if there is one) and prominent cell type in Ulcerative colitis and Çrohn’s

A

Crohn’s is granulomatous T cell prominent with increased T cell reactivity

Ulcerative colitis is non granulomatous and is neutrophil prominent, with normal or decreased levels of T cell reactivity

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

Name 6 possible clinical features of Crohn’s disease

A
  1. Diarrhea - chronic or nocturnal
  2. Abdominal pain (may also present with acute onset abdominal pain), may be around L or R iliac fossa
  3. Weight loss
  4. Fatigue; could be caused by anorexia (B12 deficient) or fever
  5. Abdominal mass or tenderness
  6. Intestinal obstruction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Define ulcerative colitis

A

Part or the whole of the mucosa of the large bowel is inflamed and may be ulcerated

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

Which parts of the bowel tend to be affected in ulcerative colitis and what is the common spreading pattern? Name 4 other characteristics of ulcerative colitis.

A

May affect parts of the colon or its entire mucosal surface
Usually starts in rectum and extends proximally
1. Symmetrical; both sides of the bowel
2. Circumferential; goes around the bowel
3. Uninterrupted pattern; No skip lesions (no cobblestone appearance)
4. Inflammation effects only the mucosa and submucosa

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

Name the three patterns of distribution for ulcerative colitis

A
  1. Proctitis; affects the rectum/last part
  2. L sided colitis; L sided iliac fossa pain, affects up the descending colon
  3. Pancolitis; affects the whole colon
18
Q

What is the cause of ulcerative colitis? Is there genetic influence in comparison to crohn’s?

A

Unknown cause, but a theory is that its an autoimmune disease caused by an inflammatory response to normal colonic microflora. There is genetic influence but less strong than crohn’s

19
Q

Describe three major histological changes you might notice in Ulcerative colitis

A
  1. Intense inflammatory cell infiltrate of lamina propria
  2. Goblet cell depletion
  3. Crypt abscesses; dead necrotic material in the middle that may cause infection
20
Q

What are pseudopolyps and why are they associated with ulcers?

A

Pseudopolyps are projecting masses of scar tissue that develop from granulation tissue, the breakdown of layers causes ulceration

21
Q

Is ulcerative colitis more common in smokers?

A

NO it’s 3X more common in non smokers

22
Q

Name 6 potential clinical features of ulcerative colitis

*Hint; characteristics of stools and pain

A

Depends on the severity and extent of the condition

  1. Bloody diarrhea; due to mucosal breakdown
  2. Urgency
  3. Tensemus; recurrent inclination to evacuate bowels
  4. Nocturnal defecation
  5. Crampy abdominal pain or ache in L iliac fossa (not acute like crohn’s can be)
  6. Pre-defecation pain relieved by passing stools
23
Q

Name four other associated conditions with UC

A
  1. Erythema Nodosum
  2. Pyoderma gangrenosum
  3. Uveitis; inflammation of eye
  4. Arthritis
24
Q

Name 5 clinical signs of UC

A
  1. Pallor
  2. Dehydration; not resorting water in the large bowel properly
  3. Mouth ulcers; diff pathology to crohn’s
  4. Abdominal tenderness
  5. Constipation; common in proctitis
25
Q

Name two ‘early findings’ and five ‘late findings’ for CD

A

Early findings:

  1. Aphthous ulcer; ulcer that forms on the mucous membrane
  2. Presence of granulomas

Late findings:

  1. Linear ulcers
  2. Cobble stone appearance
  3. Transmural inflammation
  4. Fistulas and strictures
  5. Fibrosis
26
Q

What might you see in ‘non specific’ (meaning these things may be found with any acute inflammation) and ‘specific’ (suggesting chronicity) UC?

A

Non specific; lamina propria becomes oedematous, neutrophils infiltrate invading crypts; causing cryptitis and crypt abscesses

Specific; distorted crypt structure, crypt atrophy and chronic inflammatory infiltrate

27
Q

Which IBD would you suspect if there was gross bright red bleeding?

A

UC, especially if it’s bright red which indicates the blood hasn’t been digested and the problem is distal

28
Q

What is Toxic Megacolon and how can it be seen?

A

Serious side effect of IBD, the colon (typically transverse colon) becomes dilated to >6cm. Within is a collection of infection and it may rupture which causes more infection and peritonitis. Can be seen on an abdominal X ray and a perforation can be seen easily on a CT scan

29
Q

How does perforation of a toxic megacolon influence prognosis? When would you see absent physical signs?

A

Mortality changes from 4-5% (without perforation) to 20% with perforation. Physical signs may be absent in the presence of steroids

30
Q

What might you notice on an X ray and a CT scan with CD?

A

X ray: Thumb printing; illustrates the skip lesions

CT: Fat halo sign; infiltration of fat into the mucosal layer that causes a ‘halo’ around it

31
Q

What drugs might you offer as part of IBD treatment?

A

Mesalazine, steroids, thiopurines like azothioprine (neurodrugs), methotrexate, calcineurin inhibitors

32
Q

Describe the mode of action for mesalazine, how is it used and which major IBD is it more effective on?

A

Thought to be an antioxidant that traps free radicals (byproducts of damage to the mucosal cells) and is used for maintenance - though high doses may help achieve control

More effective for UC>CD

33
Q

Name four severe side effects of Mesalazine

A
  1. Renal impairment
  2. Diarrhea
  3. Hepatitis
  4. Myopericarditis
34
Q

Describe the mode of action for steroids in IBD. Name three potential routes of administration and six severe side effects

A

Steroids have potent anti inflammatory actions and are used to obtain control over the active disease, they are not used for maintenance. They can be administered orally, topically or IV

Severe side effects include; weight gain, hypertension, glucose impairment, osteoporosis, adrenal suppression and mood disturbance

35
Q

Describe the mode of action for thiopurines, what are they used with and how is the dose determined? What must be monitored alongside a prescription and why?

A

They induce T cell apoptosis (can be useful in CD) alongside steroids, the dose is weight dependent. They also require regular monitoring of FBC and LVT as long term use is associated with bone marrow toxicity, hepatoxicity and malignancies.

36
Q

Describe the mode of action for methotrexate, when is it used and what is the dose? Name two short-term and two long-term side effects and a side effect important in expecting mothers.

A

It has anti-inflammatory action by inhibiting cytokines and eicosanoid synthesis (also inhibits dihydrofolate reductase and is cytotoxic). It’s used as a second line drug after azothioprine if it fails and it’s dose is once a week with folic acid

Short term side effects: nausea, diarrhea
Long term side effects: hepatoxicity, pneumonitis
Very teratogenic

37
Q

How do calcineurin inhibitors work?

A

They inhibit calcineurin which inhibits clonal expansion of T cell subsets

38
Q

Name three biological therapies for IBD and briefly describe how they work

A

Since TNF-a is a cytokines and key player in the inflammatory process involved in IBD…

  1. Infliximab and adalimumab are antibodies that target TNF-a
  2. Etanercept is a recombinant human TNF receptor fusion protein which inhibits the binding of TNF to its cell surface receptor
39
Q

What is the last resort medical treatment for IBD? Name four signs that this intervention is needed

A

Surgery, if the patient is defecating >8 times a day despite medication, have worsening temperatures, toxic megacolon beginning, low albumin and Hb

40
Q

Name two common surgical interventions for UC

A
  1. Colectomy

2. Ileostomy

41
Q

What is the danger of surgical intervention in Crohn’s disease patients?

A

Since the inflammation is discontinuous there is risk of the disease reappearing in another part of the GI tract and the fistulas may return

42
Q

What is one intervention that can be done for fistulas?

A

Seton stitch: guided through the fistula tract and tied exteriorly, it compresses and maintains the suture placement in the tract