Acute Appendicitis: Pathophysiology
Appendicitis is defined as an inflammation of the inner lining of the vermiform appendix that spreads to its other parts. It is caused by obstruction of the appendiceal lumen from a variety of causes.
Obstruction is believed to cause an increase in pressure within the lumen. Such an increase is related to continuous secretion of fluids and mucus from the mucosa.
Intestinal bacteria within the appendix multiply, leading to the recruitment of white blood cells and the formation of pus. This causes further increase in the intraluminal pressure leading to venous outflow obstrution. This in turn causes Ischemia of the appendiceal wall, resulting in loss of epithelial integrity and bacterial invasion.
Thrombosis of the appendicular artery and veins rapidly leads to perforation and gangrene of the appendix. As this process continues, a peri-appendicular abscess develops. This may be localized, if walled off by the omentum. Alternatively, a generalized peritonitis may result.
Obstruction is believed to cause an increase in pressure within the lumen. Such an increase is related to continuous secretion of fluids and mucus from the mucosa.
Intestinal bacteria within the appendix multiply, leading to the recruitment of white blood cells and the formation of pus. This causes further increase in the intraluminal pressure leading to venous outflow obstrution. This in turn causes Ischemia of the appendiceal wall, resulting in loss of epithelial integrity and bacterial invasion.
Thrombosis of the appendicular artery and veins rapidly leads to perforation and gangrene of the appendix. As this process continues, a peri-appendicular abscess develops. This may be localized, if walled off by the omentum. Alternatively, a generalized peritonitis may result.