If esr is not accurate, then what lab test should i need for monitoring my inflammation in the colon?

How you feel: Take it from this pathologist -- the way you feel is probably a better guide than any lab. The labs done for inflammatory bowel disease are proliferating and folks still argue about them. An occasional CBC will pick up early anemia, and chemical profile alert may alert with a low Albumin or low serum iron / high tibc. But no lab will ever take the place of "how do you feel?" stay pro-active!