The appendix is a blind-ending pouch that lies at the very start of the colon (large intestine), quite close to the point where the small bowel opens into the colon. Though it has no apparent use in humans, it is quite capable of becoming blocked by faeces, allowing it to become inflamed and infected. The result, appendicitis, produces perhaps as many as one in ten surgical admissions to hospital. As surgery is not always performed (and it is not always appendicitis), it is quite possible to suffer with appendicitis (or similar complaints) more than once.

Symptoms

The pain of appendicitis initially begins near the belly button, as the nerves supplying the appendix are related to this part of the abdomen. Once the inflammation reaches the surrounding tissues, the pain will localise in the right lower part of the abdomen over the site of the appendix. The exact site of the appendix varies and therefore so does the pain, although the typical hotspot will be two-thirds of the way from the belly button to the hip – this is known as McBurney's point. Appendicitis can also cause fever, nausea, vomiting, loss of appetite and fetid breath.

Diagnosis and Treatment

Diagnosis is based upon the above symptoms, plus examination of the abdomen. A rigid abdomen with tenderness over McBurney's point is typical. It is important to rule out other diseases with similar appearances – for instance ectopic pregnancy must be ruled out with a pregnancy test, and acute pancreatitis should be checked for with a blood test. A wide range of diseases may be to blame, including diverticulitis, kidney stones, urinary infections, gallbladder infection, and diseases of the ovaries and uterus.

If the symptoms are mild and blood tests are reassuring, the individual may be observed closely for a while. Children in particular may start to recover, showing that the diagnosis may instead be mesenteric adenitis – inflammation of the immune nodes that line the gut. However, in cases where the diagnosis and severity of disease are unclear, the individual is often taken to theatre for exploration of the abdomen. This can usually be done using a camera inserted through a small cut in the abdominal wall.

Treatment consists of removal of the appendix, which will be confirmed as abnormal by the laboratory in 80% of cases. This too can sometimes be done using keyhole surgery. In some cases, the surgeons will find a collection of pus (abscess) associated with the appendicitis, or even a ruptured appendix with infective contents leaked out into the abdomen. These can necessitate a larger wound, and are also treated with removal of the appendix plus copious washout of the abdomen with sterile fluid.

Conclusion

Appendicitis is a common surgical emergency, which is diagnosed through clinical examination and may only be confirmed at operation. A number of other conditions can produce the same appearance and some, such as ectopic pregnancy, represent equally important emergencies that must be ruled out.

Please Note: h2g2 is not a definitive medical resource. If you have any health concerns, you must always seek advice from your local GP. You can also visit NHS Direct.