IBD IBD Diagnosis and Imaging 3

Question 1

Which colonoscopic finding most reliably distinguishes UC from Crohn's colitis?

Accepted Answer

Involvement of the rectum with continuous proximal extension (UC) vs. rectal sparing with skip lesions (Crohn's)

Answer

Rectal involvement with continuous proximal extension is characteristic of UC, while rectal sparing and discontinuous skip lesions favor Crohn's colitis.

Question 2

The Simple Clinical Colitis Activity Index (SCCAI) is used to assess disease activity in which condition?

Accepted Answer

Ulcerative colitis

Answer

The SCCAI evaluates stool frequency (day/night), urgency, blood in stool, general wellbeing, and extraintestinal features to score UC activity.

Question 3

Elevated fecal calprotectin (>250 µg/g) in an asymptomatic IBD patient in clinical remission most likely indicates what?

Accepted Answer

Subclinical mucosal inflammation despite symptomatic remission

Answer

Elevated fecal calprotectin despite clinical remission suggests ongoing subclinical mucosal inflammation and predicts future relapse, warranting endoscopic evaluation.

Question 4

On CT scan, which finding is most specific for an IBD-related entero-enteric or entero-vesical fistula in Crohn's disease?

Accepted Answer

Air in the bladder (pneumaturia) without instrumentation

Answer

Pneumaturia (air in the bladder) without recent catheterization or instrumentation on CT is pathognomonic for an entero-vesical fistula, a complication of Crohn's disease.

Question 5

Which test is recommended to exclude infection before initiating or escalating immunosuppressive therapy in IBD?

Accepted Answer

Stool culture and Clostridioides difficile toxin testing

Answer

C. difficile infection must be ruled out before escalating IBD therapy, as it can mimic a flare and immunosuppression will worsen infectious colitis.

IBD - Inflammatory Bowel Disease Practice Test

IBD - Inflammatory Bowel Disease Practice Test

IBD IBD Diagnosis and Imaging 3