After colonoscopy they founnd inflamed colon and red patches what doese this mean?

Colitis...: Inflammation and red patches (erythema) are hallmarks of colitis. The causes of colitis are many and include infection, ibd (inflammatory bowel disease), circulatory problems and drugs. Sometimes even the laxative bowel prep for colonoscopy can induce these changes. Biopsy of the lining of the colon during colonoscopy can often determine the cause and dictate proper treatment.