Appendicitis is an inflammation of the appendix, which is the worm-shaped pouch attached to the cecum, the beginning of the large intestine. The appendixhas no known function in the body, but it can become diseased. Appendicitis is a medical emergency, and if it is left untreated the appendix may rupture and cause a potentially fatal infection.
Appendicitis is the most common abdominal emergency found in children and young adults. One person in 15 develops appendicitis in his or her lifetime. Themain symptom of appendicitis is increasingly severe abdominal pain. Since many different conditions can cause abdominal pain, an accurate diagnosis of appendicitis can be difficult. A timely diagnosis is important, however, because a delay can result in rupture of the appendix. When this happens, the infected contents of the appendix spill into the abdomen, and could cause a serious infection of the abdomen called peritonitis. The treatment for acute (sudden, severe) appendicitis is appendectomy, surgery to remove the appendix. Because the consequences of a ruptured appendix are life-threatening, persons suspected of having appendicitis are often taken to surgery before the diagnosisis certain.
The causes of appendicitis are not well understood, but it is believed to occur as a result of one or more of these factors: an obstruction within the appendix, the development of an ulceration (an abnormal change in tissue accompanied by the death of cells) within the appendix, and the invasion of bacteria. Under these conditions, bacteria may multiply within the appendix. The appendix may become swollen and filled with pus (a fluid formed in infected tissue, consisting of while blood cells and cellular debris), and may eventually rupture. Signs of rupture include the presence of symptoms for more than 24 hours, a fever, a high white blood cell count, and a fast heart rate. Very rarely, the inflammation and symptoms of appendicitis may disappear but recur again later.
The distinguishing symptom of appendicitis is pain beginning around or abovethe navel. The pain, which may be severe or only achy and uncomfortable, eventually moves into the right lower corner of the abdomen. There, it becomes more steady and more severe, and often increases with movement, coughing, and so forth. The abdomen often becomes rigid and tender to the touch. Increasingrigidity and tenderness indicates an increased likelihood of perforation andperitonitis. Loss of appetite is very common. Nausea and vomiting may occur in about half of the cases and occasionally there may be constipation or diarrhea. The temperature may be normal or slightly elevated. The presence of a fever may indicate that the appendix has ruptured.
A careful examination is the best way to diagnose appendicitis. It is often difficult even for experienced physicians to distinguish the symptoms of appendicitis from those of other abdominal disorders. Therefore, very specific questioning and a thorough physical examination are crucial. The physician should ask questions, such as where the pain is centered, whether the pain has shifted, and where the pain began. The physician should press on the abdomen tojudge the location of the pain and the degree of tenderness.
While laboratory tests cannot establish the diagnosis, an increased white cell count may point to appendicitis. Urinalysis may help to rule out a urinarytract infection that can mimic appendicitis. Patients whose symptoms and physical examination are compatible with a diagnosis of appendicitis are usuallytaken immediately to surgery, where a laparotomy (surgical exploration of theabdomen) is done to confirm the diagnosis. Other tests, such as a computed tomography scan (CT), and an ultrasound examination of the abdomen may be performed to avoid unnecessary surgery. Abdominal x-rays are not of much value except when the appendix has ruptured.
Often, the diagnosis is not certain until an operation is done. To avoid a ruptured appendix, surgery may be recommended without delay if the symptoms point clearly to appendicitis. If the symptoms are not clear, surgery may be postponed until they progress enough to confirm a diagnosis.
Appendicitis is usually treated successfully by appendectomy. Unless there are complications, the patient should recover without further problems. The mortality rate in cases without complications is less than 0.1%. When an appendix has ruptured, or a severe infection has developed, the likelihood is higherfor complications, with slower recovery, or death from disease. There are higher rates of perforation and mortality among children and the elderly. Appendicitis is probably not preventable, although there is some indication that adiet high in green vegetables and tomatoes may help prevent it.