Inflammatory bowel disease (IBD) patients often experience a long disease course with periods of remission and flare-ups. Currently, in addition to assessing disease stages based on symptoms, colonoscopy performed by specialized physicians is considered the standard for accurately monitoring disease activity. This procedure allows direct visualization of intestinal lesions. However, colonoscopy is complex, costly, carries the risk of complications, and is not suitable for frequent monitoring. This study aims to explore whether stool tests such as calprotectin and immunochemical tests, which are now standard for assessing disease activity in IBD, correlate with colonoscopy results. It also aims to assess the efficacy of these stool tests in determining whether the disease is in remission or active.

The objective of the study is to investigate the correlation and efficacy of stool test results, calprotectin and fecal immunochemical test, compared to colonoscopy in patients with IBD.

Inclusion Criteria:

• Patients aged 18 years or older.

• Diagnosed with inflammatory bowel disease, either ulcerative colitis or Crohn's disease.

• Scheduled for colonoscopy for various indications, including:

  1. Follow-up after treatment to assess disease remission
  2. Clinical symptoms or laboratory results suggesting disease flare, such as increased abdominal pain, more frequent diarrhea, or elevated inflammatory markers in the blood
  3. Screening for colorectal cancer in patients with long-standing inflammatory bowel disease.

Exclusion Criteria:

• Patients who decline participation in the research project. Incomplete or unsuccessful colonoscopy.
• Failure to provide stool samples.
• Patients hospitalized for reasons unrelated to inflammatory bowel disease.

IBD patients follow-up at Siriraj Hospital, Bangkok, Thailand