IBD IBD Diagnosis and Imaging 2 — Questions and Answers
Question 1: The 'string sign of Kantor' on barium follow-through indicates which Crohn's disease complication?
- Active mucosal ulceration
- Fibrostenotic stricture of the terminal ileum (Correct answer)
- Fistula formation
- Mesenteric lymphadenopathy
Correct answer: Fibrostenotic stricture of the terminal ileum
The string sign represents a severely narrowed segment of terminal ileum due to fibrostenotic stricture in long-standing Crohn's disease.
Question 2: Which endoscopic scoring system is most widely used to assess Crohn's disease activity?
- Mayo Score
- Crohn's Disease Endoscopic Index of Severity (CDEIS) (Correct answer)
- Baron Score
- Schroeder Score
Correct answer: Crohn's Disease Endoscopic Index of Severity (CDEIS)
The CDEIS quantifies mucosal lesions across five bowel segments and is the gold-standard endoscopic activity score for Crohn's disease in clinical trials.
Question 3: On MR enterography, which finding indicates active transmural Crohn's disease inflammation?
- T1 hypointense signal only
- Mural hyperenhancement and increased T2 signal (mural edema) (Correct answer)
- Loss of haustra formation
- Absent mucosal folds
Correct answer: Mural hyperenhancement and increased T2 signal (mural edema)
Active Crohn's disease on MRE demonstrates mural thickening with hyperenhancement on contrast T1 images and increased T2 signal indicating mural edema.
Question 4: Wireless capsule endoscopy in IBD is CONTRAINDICATED in which situation?
- Active rectal bleeding
- Known or suspected small bowel stricture (Correct answer)
- Prior abdominal surgery
- Iron deficiency anemia
Correct answer: Known or suspected small bowel stricture
Capsule endoscopy is contraindicated with known or suspected strictures because the capsule may become retained, requiring surgical removal.
Question 5: The Harvey-Bradshaw Index (HBI) is a clinical tool used to measure disease activity in which IBD condition?
- Ulcerative colitis
- Crohn's disease (Correct answer)
- Microscopic colitis
- Pouchitis
Correct answer: Crohn's disease
The Harvey-Bradshaw Index is a simplified clinical scoring tool assessing general wellbeing, abdominal pain, number of liquid stools, abdominal mass, and complications in Crohn's disease.
Question 6: Which laboratory finding is most characteristic of active Crohn's disease affecting the terminal ileum?
- Elevated direct bilirubin
- Vitamin B12 deficiency and macrocytic anemia (Correct answer)
- Hypercalcemia
- Elevated amylase
Correct answer: Vitamin B12 deficiency and macrocytic anemia
Vitamin B12 is exclusively absorbed in the terminal ileum; Crohn's disease affecting this region impairs B12 absorption, leading to macrocytic anemia.
IBD IBD Diagnosis and Imaging 2
The 'string sign of Kantor' on barium follow-through indicates which Crohn's disease complication?