IBD

Question 1

ASCA and pANCA in UC vs Crohn’s?

Answer 1

ASCA (+) / pANCA (-): Crohn’s. Think ASSCA. ASS = Crohn’s
ASCA (-) / pANCA (+): UC
Not definitive but good guide.

Question 2

NOD2/CARD15 how do these relate to IBD?

Answer 2

NOD2 is associated with ileal Crohn’s
CARD15 polymorphism associated with fibrostenosing disease
NOD2/CARD15 associated with severe pouchitis in UC

Question 3

Importance of OCTN1/OCTN2 mutation and IBD?

Answer 3

Mutation = whether Crohn’s will turn into cancer

Question 4

Before you use azathioprine, what do you need to make sure?

Answer 4

Make sure there’s no TMPT enzyme deficiency.

AZA is a prodrug of 6MP. Needs the TMPT

Question 5

Primary goals in anorectal Crohn’s?

Answer 5

Sepsis control and maintain continence

Seton Seton Seton. Don’t cut sphincters

Don’t do fistulotomies

Question 6

Crohn’s stricture. What are some contraindications?

Answer 6

Multiple structures within short segment
Stricture in close proximity to where you're doing a SBR
albumin <2
Active contamination
Risk of malignant transformation
Colonic stricture (resect)

Question 7

With sulfasalazine, what instructions/warnings should be given to pts?

Answer 7

Skin and urine might turn orange

Photosensitivity. Avoid UV light use sunscreen

Question 8

Compared to sporadic colorectal CA, IBD associated cancer loses

• APC function early or late?
• p53 function early or late?

Answer 8

In IBD

• APC loss occurs late. In sporadic, it is early
• p53 loss occurs early

Question 9

Patients with Crohn’s have how much higher risk of CRC compared to general population?

% cumulative risk at 10, 20, 30 years?

What about UC?

Answer 9

2-3fold increase.

3% at 10 yrs
6% at 20 yrs
9% at 30 yrs

For UC
2% at 10 years
8% at 20 years
18% at 30 yrs

Question 10

% frequency of malignancy in Crohn’s with stricture?

Answer 10

6-7%

Question 11

What to do with TNF-a inhibitor and surgery?

Answer 11

Wait 2 half lives (~4wks total)

If cannot be delayed, consider diversion if

• penetrating disease/abscess
• smoking
• recurrent disease
• emergent surgery
• anemia/blood loss
• bad nutrition

Question 12

What to do with entyvio and surgery?

Answer 12

Wait 2 half lives (~6 wks total)

Stoma if risk factors

Entyvio has been associated with increased post-op ssi

Question 13

Stelara mechanism of action? Effect on surgery?

Answer 13

IL-12, 23

Not associated with increased post-op setic complications

Question 14

2 most important risk factors for infectious complications after pouch?

Answer 14

Steroid >20mg/day

Hypoalbuminemia < 3

Question 15

Which increases the risk of structure plasty failure the most?

Active smoking
Steroid use
30 lb weight loss over the past month

Answer 15

Smoking increases risk of recurrence for Crohn’s but doesn’t affect structure plasty

Steroids &laquo_space;malnutrition increase risk of structure plasty failure

Question 16

Immunohistochemistry. What does an absence of MLH1, PMS2, MSH2, MSH6 mean?

What does it mean when MLH1 and PMS2 are both absent?

Answer 16

Absence of MLH1 often points to a sporadic cancer

Absence of PMS2, MSH2, MSH6 highly suggestive of Lynch syndrome.

PMS2 needs MLH1 to be detected. Absent PMS2 means there is a chance of Lynch syndrome, but you don’t know if PMS2 is missing because of defective gene or because MLH1 is also missing.

Do BRAF or MLH1 hypermethylation. If either is present (abnormal), tumor is likely to be sporadic. No more genetic testing.

If the result of hypermethylation or BRAF testing is normal, then pt should be referred for germline MLH1 defect