Colitis is an inflammation of the large intestine that is caused by many different disease processes, including acute and chronic infections, primary inflammatory disorders (ulcerative colitis, Crohn's colitis, lymphocytic and collagenous colitis), lack of blood flow (ischemic colitis), and history of radiation to the large bowel.

For more information about a specific type of colitis see:

• pseudomembranous colitis
• Crohn's disease (regional enteritis)
• ulcerative colitis
• ischemic colitis
• irritable bowel syndrome
• necrotizing enterocolitis
• cryptosporidium enterocolitis
• CMV colitis (a viral infection of the colon)