Introduction
The most common cause of pain in the appendix is an inflammation of its appendix caused by bacteria, commonly known as appendicitis. The appendix (“caecum”) is a part of the large intestine and is located in the right lower abdomen. The term “appendix” comes from the fact that the small and large intestine do not simply merge into one another, but that the small intestine opens into the appendix via a valve.
The appendix is “blind” at the bottom and merges upwards into the ascending part of the large intestine (ascending colon). At the blind end of the appendix hangs the so-called appendix (Latin “appendix”). This is the part that is inflamed when one speaks of appendicitis.
The appendix itself is usually not affected by the inflammation. This inflammation, which is accompanied by pain, affects about 100 out of 100000 people a year. Children, adolescents and young adults are most commonly affected, although appendicitis is rare in children under two years of age.
Causes of pain in the appendix
The most common cause of pain in the appendix is the inflammation of the appendix, colloquially known as appendicitis. This can have various causes: Since the diameter of the appendix is only about 1 cm, it can easily become blocked. This can be caused, for example, by excrement stones, kinking or scars.
In rare cases, foreign bodies can also close the opening of the appendix, for example a swallowed cherry pit. An occlusion of the appendix can result in a voiding disorder, which can lead to inflammation. Another cause of appendicitis is related to the function of the appendix.
For a long time it was assumed that the appendix is a functionless remnant of evolution. In the meantime, it is considered to be important in immune regulation. It is assumed that the lymphatic tissue of the appendix is involved in the defense against infections and the processing of immunologically relevant information.
If an inflammation occurs in the body (e.g. influenza or tonsillitis), the pathogens can enter the appendix via the blood. Due to its function in immune regulation, this can lead to a violent reaction and excessive swelling of the appendix. Another cause of pain in the appendix can be inflammation in other parts of the intestine.
These can spread to the appendix and thus cause pain. This occurs most frequently in the context of the two chronic inflammatory bowel diseases ulcerative colitis and Crohn’s disease. A so-called torsion can also lead to pain in the appendix.
This refers to a twisting of the bowel around its vascular suspensions. Due to the digestive movements of the intestine, this can lead to an obstruction of the intestine and its blood supply. A so-called intussusception can also cause pain in the area of the appendix.
In this case, sections of the intestine turn inside each other, so that the intestine and its blood supply are also constricted. Invagination and torsion usually cause cramp-like pain. In patients with a poor immune system, such as AIDS patients or cancer patients after chemotherapy, the bacteria that live in the intestine and are normally harmless can cause inflammation of the appendix.
In this case there is usually a combination of fever and pressure pain in the right lower abdomen. Pseudoappendicitis is also accompanied by pain in the appendix. This causes swelling of lymph nodes in the area of the right lower abdomen.
On the one hand, this can be directly caused by an infection with the bacterium Yersinia pseudotuberculosis. On the other hand, in children, infections in the area of the respiratory tract can lead to swelling of lymph nodes and thus cause the picture of an appendicitis. There are numerous other clinical pictures that can also manifest themselves with pain in the area of the appendix and must be considered as a differential diagnosis. These can be abscesses or tumors, for example. A hernia or diseases such as stones of the ureter and a twisting of the testis around the supplying vascular stalk can express themselves with pain in the area of the appendix.Gynecological diseases, such as cysts of the ovaries, inflammation of the fallopian tubes and ovaries or a pregnancy nested outside the uterine cavity (extrauterine pregnancy) can also be accompanied by pain in the right lower abdomen.
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