IBD Knowledge 3

Question 1

Which IBD medication requires testing for TPMT enzyme activity before initiation?

Accepted Answer

Azathioprine

Answer

TPMT (thiopurine methyltransferase) deficiency increases the risk of severe myelosuppression with azathioprine and 6-mercaptopurine, so testing is required before use.

Question 2

What is the primary indication for performing a proctocolectomy with ileal pouch-anal anastomosis (IPAA) in UC?

Accepted Answer

Medically refractory UC or dysplasia/cancer

Answer

IPAA (J-pouch surgery) is the curative procedure for UC, indicated in medically refractory disease, high-grade dysplasia, or colorectal cancer.

Question 3

Fistula-in-ano associated with Crohn's disease is best initially evaluated by which imaging modality?

Accepted Answer

MRI of the pelvis

Answer

MRI pelvis is the gold standard for evaluating perianal fistulas in Crohn's disease because it provides superior soft tissue delineation without radiation.

Question 4

Which cytokine is the primary therapeutic target of ustekinumab?

Accepted Answer

IL-12 and IL-23 (shared p40 subunit)

Answer

Ustekinumab targets the shared p40 subunit of IL-12 and IL-23, blocking both cytokines involved in Th1 and Th17 inflammatory pathways.

Question 5

What is the recommended interval for surveillance colonoscopy in a patient who has had extensive UC for 8 years?

Accepted Answer

Every 1-2 years

Answer

After 8-10 years of extensive UC, annual or biennial surveillance colonoscopy is recommended due to significantly elevated colorectal cancer risk.

IBD - Inflammatory Bowel Disease Practice Test

IBD - Inflammatory Bowel Disease Practice Test

IBD Knowledge 3