Appendicitis is a condition characterized by inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...

 of the appendix
Vermiform appendix
The appendix is a blind-ended tube connected to the cecum , from which it develops embryologically. The cecum is a pouchlike structure of the colon...

. It is classified as a medical emergency
Medical emergency
A medical emergency is an injury or illness that is acute and poses an immediate risk to a person's life or long term health. These emergencies may require assistance from another person, who should ideally be suitably qualified to do so, although some of these emergencies can be dealt with by the...

 and many cases require removal of the inflamed appendix, either by laparotomy
A laparotomy is a surgical procedure involving a large incision through the abdominal wall to gain access into the abdominal cavity. It is also known as coeliotomy.- Terminology :...

 or laparoscopy
Laparoscopy is an operation performed in the abdomen or pelvis through small incisions with the aid of a camera...

. Untreated, mortality is high, mainly because of the risk of rupture leading to peritonitis
Peritonitis is an inflammation of the peritoneum, the serous membrane that lines part of the abdominal cavity and viscera. Peritonitis may be localised or generalised, and may result from infection or from a non-infectious process.-Abdominal pain and tenderness:The main manifestations of...

 and shock. Reginald Fitz
Reginald Heber Fitz
Reginald Heber Fitz was an American physician.He graduated in 1864 from Harvard University, where, after studying in Vienna, Berlin, and Paris, he was instructor in pathological anatomy in 1870–1873, assistant professor in 1873–1878, and professor from 1878 to 1908...

 first described acute and chronic appendicitis in 1886, and it has been recognized as one of the most common causes of severe acute
Acute (medicine)
In medicine, an acute disease is a disease with either or both of:# a rapid onset, as in acute infection# a short course ....

 abdominal pain
Pain is an unpleasant sensation often caused by intense or damaging stimuli such as stubbing a toe, burning a finger, putting iodine on a cut, and bumping the "funny bone."...