3. Proctosigmoidoscopy or Colonoscopy
- These are special procedures done when the diagnosis is not clear after stool and blood tests.
- This involves the use of a thin, lighted instrument inserted into the rectum and colon to view them directly and tissue samples are taken for laboratory examination.
4. Ultrasound
- If there are complications and involvement of the abdominal organs, then further investigations, such as ultrasound, may be necessary to confirm the diagnosis.