Appendicitis and Appendectomy
Medical Author: Dennis Lee, M.D.
Medical Editor: Jay W. Marks, M.D.
What is the appendix?
The
appendix is a closed-ended, narrow
tube that attaches to the
cecum (the
first part of the
colon) like a worm. (The anatomical name for the appendix,
vermiform appendix, means worm-like appendage.) The inner lining of the appendix
produces a small amount of
mucus that flows through the
appendix and into the cecum. The wall of the appendix contains lymphatic tissue
that is part of the
immune system for making antibodies.
Like the rest of the colon, the wall of the appendix also contains a layer of
muscle.
What is appendicitis?
Appendicitis is inflammation of the appendix. It is thought that appendicitis
begins when the opening from the appendix into the cecum becomes blocked. The
blockage may be due to a build-up of thick mucus within the appendix or to stool that
enters the appendix from the cecum. The mucus or stool hardens, becomes
rock-like, and blocks the opening. This rock is called a fecalith (literally, a
rock of stool). At other times, the lymphatic tissue in the appendix may swell and block the appendix. Bacteria which normally are found within the appendix
then begin to invade (infect) the wall of the appendix. The body responds to the
invasion by mounting an attack on the bacteria, an attack called inflammation.
(An alternative theory for the cause of appendicitis is an initial rupture of
the appendix followed by spread of bacteria outside the appendix.. The cause of
such a rupture is unclear, but it may relate to changes that occur in the
lymphatic tissue that line the wall of the appendix.)
If the inflammation and infection spread through the wall of the appendix,
the appendix can rupture. After rupture, infection can spread throughout the
abdomen; however, it usually is
confined to a small area surrounding the appendix (forming a peri-appendiceal
abscess).
Sometimes, the body is successful in containing
("healing") the appendicitis without surgical treatment if the infection and
accompanying inflammation do not spread throughout the abdomen. The
inflammation, pain and symptoms may disappear. This is particularly true in
elderly patients and when antibiotics are used. The patients then may come to
the doctor long after the
episode of appendicitis with a lump or a mass in the right lower abdomen that is
due to the scarring that occurs during healing. This lump might raise the
suspicion of cancer.
Next: What are the complications of appendicitis? »
- codeine - Learn more about codeine, including a description, generic and brand names, drug class and mechanism, preparations, storage, reasons for prescription, dosing, drug interactions, effect on pregnancy and nursing mothers, and common side effects.
- CT Scan (Computerized Axial Tomography) - CT Scan (Computerized Axial Tomography, CAT scan) is a procedure that assists in diagnosing tumors, fractures, bony structures, and infections in the organs and tissues of the body.
- Abdominal Pain - Learn about abdominal pain (pain in the stomach / abdomen) including causes, symptoms, how abdominal pain is diagnosed, and how abdominal pain is treated.
Latest Medical News