Feasibility of a Minimally Invasive Diagnostic Algorithm in Suspected Crohn's Disease

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