Overview
Appendicitis is inflammation of the appendix, a small pouch attached to the large intestine, and is the most common cause of sudden abdominal pain requiring emergency surgery.
Disease Summary
- Category
- Non-Communicable Disease
- Cause
- Blockage of the appendix, often by hardened stool, leading to inflammation and infection
- Transmission
- Not applicable; appendicitis is not contagious and cannot be spread between people
- Body System
- Digestive System
- Preventable
- No
- Curable
- Yes
Symptoms
Common Symptoms
Symptoms typically develop and worsen over several hours.
Abdominal Pain
Pain that often starts near the navel and moves to the lower right abdomen, worsening over hours.
Loss of Appetite
A sudden decrease in appetite commonly accompanies early symptoms.
Nausea and Vomiting
Often occurs shortly after the onset of abdominal pain.
Low-grade Fever
A mild fever frequently develops as inflammation progresses.
Danger Signs
Seek emergency medical attention immediately if any of the following develop.
Severe, Worsening Pain
Pain that becomes intense or spreads across the abdomen may indicate the appendix has ruptured.
High Fever
A high fever combined with abdominal pain suggests a more serious infection.
Rigid or Swollen Abdomen
A hard, swollen abdomen can indicate peritonitis, a serious complication requiring emergency care.
Rapid Heartbeat
A fast heart rate alongside severe abdominal pain may indicate a serious infection.
Diagnosis
Clinical Assessment
Diagnosis begins with a physical examination, including checking for tenderness in the lower right abdomen.
Imaging
Ultrasound or CT scans help confirm inflammation of the appendix and rule out other causes of abdominal pain.
Laboratory Tests
Blood and urine tests help support the diagnosis and rule out other conditions.
Laboratory Tests
Complete Blood Count (CBC)
An elevated white blood cell count often indicates infection or inflammation.
Urinalysis
Helps rule out a urinary tract infection or kidney stones as the cause of abdominal pain.
Abdominal Ultrasound
Can visualize an inflamed appendix, particularly useful in children and pregnant women.
CT Scan of the Abdomen
Provides detailed imaging to confirm appendicitis and assess for complications such as rupture.
Treatment
Appendectomy (Surgical Removal)
Surgical removal of the appendix is the standard treatment and prevents the risk of rupture.
Antibiotics
Antibiotics are used before surgery and, in some mild, early cases, may be used alone under close medical supervision.
Prevention
Know the early warning signs
Being aware of symptoms such as worsening abdominal pain, nausea, and fever helps prompt earlier evaluation.
Seek care promptly for abdominal pain
Early medical evaluation for worsening or persistent abdominal pain can prevent the appendix from rupturing.
Eat a fibre-rich diet
Some evidence suggests a diet high in fibre may be associated with a lower risk of appendicitis, though this is not proven to prevent it.
Avoid delaying evaluation of unclear abdominal pain
Because appendicitis can be difficult to distinguish from other conditions, timely medical assessment is the best way to avoid complications.
Risk Factors
High Risk
These factors substantially increase the likelihood of developing appendicitis.
- Age between 10 and 30 years, though it can occur at any age
- Family history of appendicitis
- Blockage of the appendix by hardened stool (a fecalith)
Increased Risk
These factors are associated with a moderately higher risk of appendicitis.
- Male sex, which carries a slightly higher lifetime risk
- Certain infections that cause swelling of lymphoid tissue in the appendix
- Digestive tract conditions such as inflammatory bowel disease
Additional Contributing Factors
Other factors linked with an increased likelihood of appendicitis.
- Low-fibre diet
- Abdominal trauma
- Tumours or growths blocking the appendix, though uncommon
Complications
Ruptured Appendix
An untreated appendix can burst, spreading infection throughout the abdomen.
Peritonitis
Infection spreading throughout the abdominal cavity is a life-threatening complication requiring emergency surgery.
Abscess Formation
A pocket of infection can form around a ruptured appendix, sometimes requiring drainage before or instead of surgery.
When to Seek Medical Care
Worsening Abdominal Pain
Pain that increases in intensity or shifts to the lower right abdomen needs urgent evaluation.
Fever with Abdominal Pain
Combined fever and abdominal pain should be assessed promptly.
Inability to Keep Food or Fluids Down
Persistent vomiting alongside abdominal pain needs medical attention.
Rigid or Swollen Abdomen
A hard, swollen abdomen may indicate a ruptured appendix and requires emergency care.
Prognosis
Excellent with Prompt Surgery
Most people recover fully and quickly after timely appendectomy.
Higher Risk with Delayed Treatment
Delayed diagnosis increases the risk of rupture and more serious complications.
Full Recovery Without Lasting Effects
After recovery from surgery, most people do not need to make any changes to diet, exercise, or lifestyle.
Differential Diagnosis
Ovarian Cyst or Torsion
Can cause similar lower abdominal pain in women and needs to be distinguished through examination and imaging.
Urinary Tract Infection
Can cause abdominal or pelvic discomfort that may resemble early appendicitis.
Gastroenteritis
Causes nausea, vomiting, and abdominal pain but typically lacks the localized tenderness seen in appendicitis.
Ectopic Pregnancy
A pregnancy-related emergency that can cause similar lower abdominal pain in women of childbearing age and must be ruled out.
References
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
NIH guidance on the symptoms, diagnosis, and treatment of appendicitis.
Mayo Clinic
Patient-focused overview of appendicitis symptoms and causes.
NCBI Bookshelf (StatPearls)
Clinical reference on the diagnosis and management of acute appendicitis.
Frequently Asked Questions
Can appendicitis be treated without surgery?
In some mild, early cases, antibiotics alone may be considered, though surgery remains the standard treatment since appendicitis often returns without it.
Is appendicitis an emergency?
Yes. Appendicitis requires prompt medical evaluation, since an untreated appendix can rupture and cause serious infection.
Can you live without an appendix?
Yes. The appendix is not essential, and most people live normally after it is removed.
Can appendicitis be prevented?
There is no proven way to reliably prevent appendicitis, so recognizing symptoms early and seeking prompt care is the best way to avoid complications.