The purpose of this study is to determine whether 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 CD compared to the traditional invasive approach using ileocolonoscopy with biopsies as first line diagnostic modality

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. Each patient goes through a standardized work-up including medical history, physical examination, C-reactive protein, fecal calprotectin, ileocolonoscopy, PCCE, MREC and US. All examinations are reviewed and described in a standardized fashion. The radiologists and physicians describing PCCE, MREC, and US are blinded to the findings at ileocolonoscopy and the other imaging modalities.

Inclusion Criteria:

General criterion

All 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
• Signed informed consent

Clinical criterion Diarrhea and/or abdominal pain for more than 1 month (or repeated episodes of diarrhea and/or abdominal pain) associated with one or more of the following findings: (1) C-reactive protein (CRP) >5 mg/L, (2) thrombocytosis (> 400 x 109/L), anemia (hemoglobin < 7.0 mmol/L for women and < 8.0 mmol /L for men or a decrease > 0.5 mmol/L compared to the usual level), (3) prolonged fever (> 37.5 C for more than 2 weeks), (5) weight loss (≥ 3 kg or ≥ 5% compared to the normal body weight), (6) perianal abscess/fistula, or (7) a family history of inflammatory bowel disease.

Exclusion Criteria:

• Acute bowel obstruction
• Intake of NSAIDs or acetylsalicylic acid ≤ 4 weeks before inclusion except prophylactic treatment with low dose Aspirin (≤ 150 mg per day)
• Pregnancy or lactation
• Alcohol or drug abuse
• Known gastrointestinal disorder other than inflammatory bowel disease
• Renal failure defined by a plasma-creatinine above the normal reference range
• Claustrophobia, cardiac pacemaker or implanted magnetic foreign bodies that precludes MREC
• Interpreter required or inability to understand the oral and written information
• Colonoscopy contraindicated, performed within 3 months or unwillingness to go through colonoscopy