The goal of this clinical trial is to learn whether a camera pill examination of the whole bowel can be used to diagnose Crohn's disease instead of colonoscopy and a small bowel examination (either MRI or camera pill) in patients aged 18-40 years suspected of having Crohn's disease.

The main question it aims to answer is:

How many patients examined with a camera pill examination of the whole bowel will have a complete examination of the whole bowel and have a diagnosis made without need for any more examinations?

Researchers will compare with patients examined with colonoscopy and a small bowel examination.

Participants will:

• Be examined with either a camera pill examination of the whole bowel, or a colonoscopy and a small bowel examination
• Have their electronic medical records checked to see if a diagnosis has been made
• Have an interview every three months if diagnosed with an inflammatory bowel disease or after a year if no disease was found

Inclusion Criteria:

• Clinical suspicion of CD*

• Age 18-40 years

• Signed informed consent

  *A clinical suspicion of CD is based on the following definition:

• Diarrhea and/or abdominal pain for more than 1 month (or repeated episodes of diarrhea and/or abdominal pain) and either

  • fecal calprotectin ≥ 200 mg/kg or
  • fecal calprotectin ≥ 50 mg/kg plus one or more of the following findings:

• C-reactive protein (CRP) > 5 mg/L

• 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)

• Prolonged fever (> 37.5 ◦C for more than 2 weeks)

• Weight loss (≥ 3 kg or ≥ 5% compared to the normal body weight)

• Perianal abscess / fistula

• Family history of inflammatory bowel disease.

Exclusion Criteria:

• Previous intestinal resection
• Positive serologic markers for celiac disease
• Positive stool polymerase chain reaction for pathogenic bacteria
• Positive stool polymerase chain reaction for intestinal parasites
• Suspected or established acute bowel obstruction (ileus)
• Intake of NSAIDs or acetylsalicylic acid ≤ 4 weeks before inclusion, except low-dose, prophylactic acetylsalicylic acid (≤ 150 mg per day)
• Intake of opioid or opioid-like medications ≤ 1 week before inclusion
• Pregnancy or lactation
• Inability to comply with protocol requirements, e.g. for reasons including alcohol or recreational drug abuse
• Known gastrointestinal disorder other than functional gastrointestinal disorders
• Renal failure defined by a plasma-creatinine above the normal reference range