Inflamed appendix. Gross specimen of an inflamed appendix that has been removed in appendicitis. An inflamed appendix normally results from a blockage that develops into a bacterial infection. Blockage occurs because the appendix is a small, redundant loop of the intestine. Appendicitis causes severe and localised abdominal pain. If not treated, by surgical removal, the blood supply may be cut off and the tissue will die and the appendix may also burst. This can lead to serious complications such as peritonitis when the intestinal contents infect the abdominal cavity.