1. What is the clinical problem?

2. Develop a differential diagnosis by listing diseases which may present with this problem, especially in an elderly person?

3. What is low volume and high volume  hematochezia. How does that help in the differential diagnosis?

4. How would you proceed to investigate for  hematochezia ?

5. What is your diagnosis?

6. Compare and contrast melena, hematochezia and occult blood in the stool.