Short summary

Non-invasive endoscopic procedures (pillcam colon capsule endoscopy, PCCE) and non-ionizing radiological modalities (MR enterocolonography, MREC and ultrasound, US) - offer a sufficiently high diagnostic validity in patients with suspected Crohns disease (CD) compared to the traditional invasive approach using ileocolonoscopy with biopsies as first line diagnostic modality.The aim of this study is to evaluate the applicability of PCCE, MREC and US as the first diagnostic modality in patients with suspected CD compared to the current gold standard (ileocolonoscopy).

Rationale

Current guidelines for diagnosing Crohns disease (CD) suggest ileocolonoscopy with multiple biopsies from the terminal ileum and each colonic segment as the first diagnostic examination. However, irrespective of the findings at ileocolonoscopy, further investigations are recommended to examine the location and extent of any CD in the upper small bowel. 

Ileocolonoscopy is regarded as gold standard for diagnosing CD located in colon and terminal ileum. However, the examination is invasive, associated with patient discomfort and a small risk of colonic perforation (< 1 per 1,000 colonoscopies). Furthermore, a complete ileocolonoscopy is not always possible. In expert hands, ileoscopy is achieved in 85-90% of patients and in approximately 10%, CD is located outside the reach of the colonoscope. 

In recent years, technological advances have improved non-invasive modalities for diagnosing CD. The main modalities are magnetic resonance imaging (MRI), ultrasound, and capsule endoscopy. All modalities are able to visualize both the small intestine and colon in one examination. How to apply these modalities in the diagnostic algorithm, and whether CD can be diagnosed without performing ileocolonoscopy is still unknown.

The aim of this study is to evaluate the applicability of PCCE, MREC and US as the first diagnostic modality in patients with suspected CD compared to the current gold standard (ileocolonoscopy).

This is a prospective, blinded, multicenter study of the diagnostic validity, inter-observer agreement, image quality and subjective experience of discomfort with PCCE, MREC and US in patients with suspected CD.  Ileocolonoscopy serves as the diagnostic gold standard. Patients are recruited from 3 centers in the Region of Southern Denmark managing adult patients with inflammatory bowel diseases.

Description of the cohort

Newly refereed patients with suspected CD are recruited from the gastroenterology outpatient clinics. All patients meet the of the following:

• Clinical suspicion of CD
• Age > 15 years
• Negative serologic markers for celiac disease, negative stool culture (or polymerase chain reaction) for pathogenic bacteria and a negative microscopy for intestinal parasites
• Fecal calprotectin > 50 mg/kg

Collaborating researchers and departments

Department of Gastroenterology, Odense University Hospital

• Professor Jens Kjeldsen, PhD

Department of Internal Medicine, Section of Gastroenterology, Lillebaelt Hospital Vejle

• Consultant Michael Dam Jensen, PhD
• Staf specialist Mie Juhl

Department of Radiology, Lillebaelt Hospital Vejle 

• Professor Søren R. Rafaelsen, DMSc