Appendicitis is an inflammation of the appendix, a small pouch attached to the large intestine. The exact cause of appendicitis is not well understood, but it is believed to occur when the opening from the appendix to the large intestine becomes blocked, allowing bacteria and other materials to build up inside the appendix and cause inflammation.
The signs and symptoms of appendicitis may include abdominal pain that begins near the navel and then moves to the right lower side of the abdomen, loss of appetite, nausea, vomiting and fever. In some cases, constipation or diarrhoea, abdominal swelling, and abdominal tenderness may also occur.
Appendicitis is considered a medical emergency and prompt medical attention is required to reduce the risk of complications. The most common treatment for appendicitis is surgical removal of the appendix (appendectomy), which can usually be performed using minimally invasive techniques and requires a hospital stay of one to two days.
SYMPTOMS
The symptoms of appendicitis can vary, but typically include:
- Abdominal pain: The pain begins near the navel and then moves to the right lower side of the abdomen. It may become more intense over time and may be relieved by lying down and putting pressure on the abdomen.
- Loss of appetite: The person may not feel like eating or drinking anything.
- Nausea and vomiting: The person may feel sick to their stomach and may vomit.
- Fever: The person may have a low-grade fever, which is a sign that the body is fighting an infection.
- Constipation or diarrhoea: The person may have trouble passing stool or may have diarrhoea.
- Abdominal swelling: The person may have swelling in the abdomen.
- Abdominal tenderness: The person may feel pain when the healthcare provider presses on the abdomen.
These symptoms may not always be present or may be difficult to distinguish from symptoms of other conditions, such as a stomach virus.
Pathophysiology
The pathophysiology of appendicitis is thought to be caused by a blockage of the opening of the appendix. This blockage can be due to a variety of factors, including:
- Fecalith (a hard, pebble-like piece of stool): A fecalith can become lodged in the appendix and cause a blockage.
- Enlarged lymphoid tissue: The appendix contains lymphoid tissue, which helps to fight infections. If the lymphoid tissue becomes enlarged, it can block the opening of the appendix.
- Inflammation of the appendix: The appendix can become inflamed for a variety of reasons, such as infection, injury or disease. This inflammation can cause the walls of the appendix to thicken, leading to a blockage.
Once the opening of the appendix is blocked, the blood supply to the appendix is disrupted. This can cause the appendix to become infected and filled with pus, leading to inflammation and swelling of the appendix. If left untreated, the pressure within the appendix can increase, causing the appendix to burst, which can lead to peritonitis (an infection of the lining of the abdomen).
McBurney’s point
McBurney’s point is a specific location on the right lower side of the abdomen that is used as a reference for diagnosing appendicitis. It is named after Dr. Charles McBurney, a 19th-century American surgeon who first described the location of the appendix and its relation to pain in patients with appendicitis.
McBurney’s point is located approximately one-third of the distance from the anterior superior iliac spine (a bony prominence at the top of the hip bone) to the umbilicus (belly button). This location is often used as a reference for locating the appendix because it is thought to be the most common site of pain in patients with appendicitis.
Physical examination of a patient with suspected appendicitis will typically involve looking for tenderness, pain, or discomfort in the area around McBurney’s point. If tenderness or pain is present in this area, it may suggest that the patient has appendicitis and further tests, such as a CT scan or ultrasound, may be performed to confirm the diagnosis.