Inflammatory Bowel Disease

Question 1

What part of the bowel is involved in UC?

Answer 1

always involves rectum, extends proximally but is limited to the colon

Question 2

What are the histological findings of UC?

Answer 2

mucosal/submucosal involved, lymphocytic infiltrate, crypt distortion, no granulomas

Question 3

What part of the GIT is involved in crohn’s disease?

Answer 3

may affect any part, may have skip lesions

Question 4

What are the histological findings of crohn’s disease?

Answer 4

transmural, granulomas in 50% of cases

Question 5

What are some of the bowel complications of crohn’s disease?

Answer 5

fistulisation, obstruction, microperforation, strictures

Question 6

What are the clinical features of the NOD2/CARD15 variant of crohn’s disease?

Answer 6

younger age of onset, small bowel involvement, stricturing phenotype, early initial surgery/surgical recurrence

Question 7

Which medications may trigger flares of UC?

Answer 7

aspirin, NSAIDs, OCP

Question 8

What protects against UC/

Answer 8

smoking, appendicectomy

Question 9

What is faecal calprotectin?

Answer 9

a protein released by inflammatory cells in the gut, not usually present in the stool, elevated in bowel inflammation

Question 10

What is a positive ASCA and negative ANCA suggestive of?

Answer 10

crohn’s disease

Question 11

What is a positive ANCA and negative ASCA suggestive of?

Answer 11

UC

Question 12

What is perianal disease suggestive of?

Answer 12

crohn’s disease

Question 13

What is sparing of the rectum suggestive of?

Answer 13

crohn’s disease

Question 14

What are the extraintestinal manifesations of IBD associated with active disease?

Answer 14

oral ulcers, erythema nodosum, large joint arthritis, episcleritis

Question 15

What are the extraintestinal manifesations of IBD independent of GI disease?

Answer 15

PSC, ank spond, uveitis, pyoderma gangreonsum, kidney stones, gall stones

Question 16

What is the role of sulfasalazine/5-aminosalicylates?

Answer 16

used in the treatment of mild to moderate UC to induce and maintain remission

Question 17

What is the effect of sulfsalazine/5-aminosalicylates on colorectal cancer?

Answer 17

reduces risk in UC patients

Question 18

Do steroids maintain remission in IBD?

Answer 18

no

Question 19

What is entocort and when is it useful?

Answer 19

budesonide with extensive first-pass metabolism so it is delivered specifically to the terminal ileum and proximal colon -> effective in ileocaecal crohn’s

Question 20

Whay is cortiment and when is it useful?

Answer 20

budeonside attached to a matrix so it has colonic release -> effective in UC

Question 21

What is the mechanism of action of azathioprine/6-mercaptopurine?

Answer 21

metabolised to 6-thioguanine which inhibit purine synthesis, inhibits T and B cell proliferation and induces T cell apoptosis

Question 22

What is TPMT?

Answer 22

An enzyme (thiopurine methyltransferase) - if patient’s have poor enzyme activity can be at risk of severe neutropaenia on azathioprine

Question 23

What is measured for therapeutic drug monitoring of azathioprine?

Answer 23

6-MMP (inactive metabolite) and 6-TGN (active metabolite)

Question 24

What does it mean if patients have low 6-TGN and low 6-MMP?

Answer 24

either non adherance or underdosing

Question 25

What does it mean if patients have high 6-TGN and high 6-MMP?

Answer 25

refractory -> need to use another drug

Question 26

What does it mean if patients have low 6-TGN and high 6-MMP?

Answer 26

they are thiopurine resistant 'shunters' -> can use allopurinol in addition to stop shunting of the pathway (and reduce dose of thioprine)

Question 27

What are the side effects of thiopurines?

Answer 27

allergic reactions, leukopaenia, hepatitis, pancreatitis, infections, non hodgkins lymphoma, non melanoma skin cancer

Question 28

What is the mechanism of action of cyclosporine?

Answer 28

calcineurin antagonist

Question 29

What is the use of cyclosporine?

Answer 29

used as rescue therapy for severe steroid refractory UC to avoid surgery - > can't be used long term or in crohn's

Question 30

Which anti-TNF agents are available for use in IBD?

Answer 30

infliximab, adalimumab, golimumab

Question 31

What are the adverse effects of anti-TNF therapy?

Answer 31

lupus, serious infection, TB, non hodgkin's lymphoma, melanoma, psoriadorm reactions

Question 32

What is the mechanism of action of vedolizumab?

Answer 32

binds alpha 4 beta 7 integrin on surface of T lymphocytes -> inhibits trafficking of leukocytes to sites of inflammation

Question 33

What is the mechanism of action of ustekinumab?

Answer 33

monoclonal antibody to p40 subunit of IL-12/IL-23

Question 34

Which patients are most at risk of hepatosplenic T cell lymphoma?

Answer 34

young males on thiopurine and anti-TNF

Question 35

What is the usual treatment plan for crohn's?

Answer 35

start with corticosteroid and azathioprine/6-MP, taper steroids, if continue steroid free remission continue monotherapy, if not in steroid free remission add infliximab or adalimumab

Question 36

What is the usual treatment plan for UC?

Answer 36

start with aminosalicylate, if ongoing disease add corticosteroid and thiopurine, if ongoing disease add anti-TNF

Question 37

What are the features of acute severe colitis?

Answer 37

> 6 bloody stools per day plus one of HR > 90, T > 37.8, Hb < 105 or ESR > 30

Question 38

What is the treatment of acute severe colitis?

Answer 38

IV steroids, IVT, IV abx, tranfuse to Hb >100, early surgical review

Question 39

What factors increase risk of colorectal cancer in IBD?

Answer 39

``` disease duration disease extent severity of inflammation PSC FHx of CRC presence of dysplasia ```