Introduction: In suspected Crohn's disease (CD), current diagnostic guidelines recommend additional small bowel imaging irrespective of the findings at ileocolonoscopy. Magnetic resonance imaging enterography (MRE) and computed tomography enterography (CTE) are regarded first line imaging techniques and should generally precede capsule endoscopy.
Material and methods: This article brings together results from a prospective blinded diagnostic study of MRE, CTE, capsule endoscopy and faecal calprotectin (fCal) in 93 patients undergoing their first diagnostic work-up for CD.
Results: In patients with suspected CD, fCal is useful for the identification patients without need for colonoscopy or small bowel imaging. Patients with an elevated fCal should undergo colonoscopy including a persistent attempt to intubate the terminal ileum. CD isolated in the upper small bowel is rare, and in patients with a normal ileocolonoscopy or non-complicated CD in the colon and/or terminal ileum, small bowel imaging provides little extra information compared to ileoscopy alone. Small bowel imaging is primarily indicated if ileoscopy is not achieved and capsule endoscopy is recommended as first line imaging technique. If small bowel stenosis is not ruled out, a preceding test with a patency capsule can be performed to avoid capsule retention. MRE and CTE are complimentary modalities preferably used in patients with stenosis detected at ileocolonoscopy or suspicion of extra-intestinal disease complications.
Conclusion: Our results suggest that a diagnostic approach different to that described in the guidelines may be expedient.
Funding: not relevant.
Trial registration: The study was approved by the Ethics Committee of Southern Denmark (S-20070072) and the Danish Data Protection Agency (journal number: 2007-41-0675). ClinicalTrials.gov identifier: NCT01019460.