Appendicitis

What is appendicitis?

Appendicitis is swelling and infection of the appendix, a small pouch attached to the large bowel. It happens when the opening of the appendix becomes blocked. Without treatment the appendix can burst and spread infection, so it needs urgent assessment. Removing the appendix causes no lasting problem in adults.

The appendix has no essential role in adults.

What causes appendicitis?

Appendicitis starts when the opening of the appendix is blocked, by hardened stool or swollen lymph tissue. Infection then builds up behind the blockage, and pressure rises as the inflammation worsens. If it is not treated, the appendix can burst.

• A blockage of the appendix opening
• Hardened stool or swollen lymph tissue
• Infection building up behind the blockage

What are the symptoms?

Appendicitis typically causes pain that starts around the navel and moves to the lower right abdomen over a few hours, with loss of appetite, nausea or vomiting and a fever. The area is tender to press. Pain can be less typical in pregnancy, young children and older people.

• Pain moving from the navel to the lower right abdomen
• Loss of appetite, nausea, or vomiting
• Fever
• Tenderness when pressed
• Constipation or diarrhoea

When should I see a colorectal surgeon?

Appendicitis needs urgent assessment: seek emergency care for abdominal pain that keeps worsening or moves to the lower right side. Sudden severe pain, a rigid abdomen, high fever with chills, or confusion is more serious. Pain that eases briefly and then returns strongly can mean the appendix has burst.

The warning signs below need prompt attention.

• Sudden worsening pain
• A rigid abdomen
• High fever and chills
• Confusion or severe illness
• Pain that briefly eases then returns strongly

How is it diagnosed?

Appendicitis is diagnosed in hospital by examining the abdomen, blood tests and a urine test to rule out other causes, followed by an ultrasound or CT scan to look for a swollen appendix. Many conditions cause lower abdominal pain, so tests are needed rather than guessing from symptoms.

• Examination and blood tests
• Urine test to rule out other causes
• Ultrasound or CT
• Assessment in hospital

How is appendicitis treated?

Appendicitis is usually treated by appendicectomy, the operation to remove the appendix, most often by keyhole surgery. Antibiotics are given around the operation, and an abscess from a burst appendix is treated. Selected uncomplicated cases may be managed with antibiotics under specialist care.

• Appendicectomy, usually laparoscopic
• Antibiotics around the operation
• Treatment of an abscess if the appendix has perforated
• Fluids and pain relief

What are the risks and complications?

Risks of appendicectomy include wound infection, leakage from the bowel stump, an abscess inside the abdomen, delayed healing after a burst appendix, and the general risks of anaesthesia. Delaying treatment raises the risk of perforation, which is more serious.

• Wound infection
• Leakage from the bowel stump
• Abscess inside the abdomen
• Delayed healing after perforation
• General anaesthesia risks