The lumen of the appendix is very small and there is little room for swelling when it becomes inflamed. The initial cause of inflammation is not always clear. Microbial infection is commonly superimposed on obstruction by,for example,hard faecal matter(faecoliths),kinking or a foreign body. Inflammatory exudate,with fibrin and phagocytes,causing swelling and ulceration of the mucous membrane lining. In the initial stages,the pain of appendicitis is usually located in the central area of the abdomen. After a few hours,the pain shifts and is localised to the region above the appendix. In mild cases the inflammation subsides and healing takes place. In more severe cases microbial growth progresses,leading to suppuration,abscess formation and further congestion. The rising pressure inside the appendix occludes first the veins,then the arteries and ischaemia develops,followed by gangrene and rupture.
COMPLICATIONS OF APPENDICITIS.
- Peritonitis. The peritoneum becomes acutely inflamed,the blood vessels dilate and excess serious fluid is secreted. It occurs as a complication of appendicitis when:
- Microbes spread through the wall of the appendix and infect the peritoneum.
- An appendix becomes gangrenous and ruptures discharging it’s contents into the peritoneal cavity.
- An appendix abscess ruptures and pus enters the peritoneal cavity.
