IBD IBD Pharmacotherapy 2

Question 1

Ustekinumab (Stelara) targets which cytokine pathway in treating Crohn's disease?

Accepted Answer

IL-12 and IL-23 via the p40 subunit

Answer

Ustekinumab is a fully human monoclonal antibody targeting the shared p40 subunit of IL-12 and IL-23, blocking Th1 and Th17 immune responses.

Question 2

Which serious opportunistic infection risk requires tuberculosis (TB) screening before initiating anti-TNF therapy in IBD?

Accepted Answer

TNF blockade impairs macrophage killing of Mycobacterium tuberculosis, risking TB reactivation

Answer

TNF-α is critical for granuloma maintenance and mycobacterial containment; blocking it can reactivate latent TB, requiring screening (PPD/IGRA) before treatment.

Question 3

Tofacitinib (Xeljanz) is approved for which IBD indication in the United States?

Accepted Answer

Moderately to severely active ulcerative colitis

Answer

Tofacitinib, a JAK1/JAK3 inhibitor, is FDA-approved for moderately to severely active UC in adults who have failed TNF inhibitors.

Question 4

Metronidazole and ciprofloxacin in Crohn's disease are most appropriate for treating which complication?

Accepted Answer

Perianal fistulas and abscesses

Answer

Antibiotics like metronidazole and ciprofloxacin are used adjunctively for perianal fistulas and abscesses in Crohn's disease, targeting polymicrobial perianal flora.

Question 5

Combination therapy with infliximab and azathioprine is superior to monotherapy primarily because of which pharmacological interaction?

Accepted Answer

Azathioprine reduces infliximab immunogenicity by suppressing anti-drug antibody formation

Answer

Azathioprine reduces the formation of anti-infliximab antibodies (immunogenicity), maintaining higher trough levels and prolonging infliximab efficacy.

IBD - Inflammatory Bowel Disease Practice Test

IBD - Inflammatory Bowel Disease Practice Test

IBD IBD Pharmacotherapy 2