What Is Appendicitis? Symptoms, Diagnosis and Treatment

Created: 29.04.2024 · Last Updated: 18.08.2026 · Category: General Surgery · Prepared by the Academic Hospital Web and Editorial Board.

What Is the Appendix?

The appendix is a small, narrow, tube-shaped organ extending from the caecum, the first part of the large intestine.

Inflammation of the appendix is known as appendicitis.

Where Is the Appendix Located?

The appendix is generally located in the right lower abdomen, close to the point where the small intestine joins the large intestine.

Its exact position varies between individuals. It may lie behind the caecum, extend towards the pelvis or point in another direction.

The appendix is not fixed at a point immediately to the right of the navel. Its anatomical position can vary, which can also influence the location of appendicitis pain.

What Does the Appendix Do?

The appendix is not essential for life and people can live normally after it is removed.

It contains lymphoid tissue associated with the immune system and may contribute to intestinal immune function, particularly earlier in life.

Research has also explored a possible role in maintaining the intestinal microbiome, although its full biological functions remain incompletely understood.

What Is Appendicitis?

Acute appendicitis is inflammation of the appendix and is one of the most common surgical causes of acute abdominal pain.

As inflammation progresses, swelling, impaired blood supply and tissue injury can develop. Some patients may develop perforation, an abscess or infection within the abdominal cavity.

What Causes Appendicitis?

Obstruction of the appendix lumen is one recognised mechanism.

Possible contributing factors include faecaliths or appendicoliths, enlargement of lymphoid tissue and, less commonly, other structural causes.

Obstruction can lead to increasing pressure, bacterial proliferation and inflammation, although a specific obstructing cause is not identified in every patient.

What Are the Symptoms of Appendicitis?

  • Abdominal pain
  • Loss of appetite
  • Nausea
  • Vomiting
  • Fever
  • Abdominal tenderness
  • Pain worsened by movement or coughing
  • Occasionally constipation or diarrhoea

Children, older adults and pregnant patients may have less typical symptoms.

Where Is Appendicitis Pain Felt?

Classically, pain begins around the navel or central abdomen and moves towards the right lower abdomen over several hours.

The pain often becomes progressively more noticeable and may worsen with movement, coughing or abdominal muscle tension.

Not every patient follows this classic pattern because the position of the appendix varies.

How Is Appendicitis Diagnosed?

Diagnosis is based on a combination of clinical assessment rather than a single symptom or test.

Assessment can include:

  • Medical history and progression of pain
  • Abdominal examination
  • Blood tests
  • Urine testing
  • Pregnancy testing when appropriate
  • Ultrasound, CT or MRI when indicated

Inflammatory markers such as the white blood cell count and CRP can support the diagnosis but cannot confirm or exclude appendicitis by themselves.

Are Ultrasound, CT or MRI Required?

The choice of imaging depends on age, pregnancy status, clinical findings and local resources.

Ultrasound does not use radiation and can be a useful first-line examination, particularly in children and younger patients.

CT is one of the most definitive imaging methods in adults and can also help identify perforation or abscess.

MRI avoids ionising radiation and may be used in selected patients, including during pregnancy.

What Are Uncomplicated and Complicated Appendicitis?

In uncomplicated appendicitis, the appendix is inflamed without findings such as perforation, a significant abscess or diffuse peritonitis.

Complicated appendicitis can involve perforation, abscess, phlegmon or more extensive intra-abdominal infection.

This distinction is important when selecting treatment.

How Is Appendicitis Treated?

Treatment depends on disease severity, imaging findings, age, overall health and clinical progression.

Options can include appendectomy, antibiotic treatment in selected uncomplicated cases, and antibiotics with or without drainage for selected abscesses.

Current WSES guidance continues to regard laparoscopic appendectomy as the standard surgical approach.

Can Appendicitis Be Treated With Antibiotics?

Yes. Antibiotic-only treatment can be an option for selected patients with uncomplicated acute appendicitis.

This approach can avoid immediate surgery and general anaesthesia, but there remains a risk of recurrence or the need for appendectomy at a later date.

Non-operative treatment is therefore not appropriate for every patient.

Neither “all appendicitis requires immediate surgery” nor “all appendicitis can be cured with antibiotics” is correct. Treatment should be individualised according to the type of appendicitis and the patient's clinical condition.

What Is an Appendectomy?

An appendectomy is the surgical removal of the appendix.

It is the definitive surgical treatment for acute appendicitis.

The operation can be performed using laparoscopic or open surgery. Laparoscopy is generally preferred in suitable patients.

How Is Laparoscopic Appendectomy Performed?

During laparoscopic appendectomy, a camera and surgical instruments are introduced through several small abdominal incisions.

The appendix is separated from surrounding tissues, its blood supply is controlled and the appendix is removed.

Potential advantages in suitable patients include smaller incisions, less postoperative discomfort and an earlier return to normal activity.

Open surgery may still be required in selected clinical situations.

What Happens if the Appendix Perforates?

Perforation means that a hole has developed through the wall of the appendix.

Infected material can then spread into the abdomen and lead to complications such as:

  • Intra-abdominal abscess
  • Peritonitis
  • Sepsis

Not every untreated case inevitably perforates, but suspected appendicitis should be assessed promptly because progression can occur.

Recovery After Appendectomy

Recovery depends on whether appendicitis was uncomplicated or complicated, the operation performed and the patient's overall health.

After uncomplicated laparoscopic appendectomy, patients are generally encouraged to mobilise and resume oral intake early, with discharge planned when clinically appropriate.

Perforated appendicitis or an abscess can require a longer hospital stay and additional antibiotic treatment.

When Is Urgent Medical Assessment Required?

  • Persistent or progressively worsening abdominal pain
  • Marked tenderness in the right lower abdomen
  • Repeated vomiting with abdominal pain
  • Fever with significant deterioration in general condition
  • A rigid abdomen or widespread tenderness
  • Severe pain that temporarily improves and then becomes more widespread
  • Fainting, altered consciousness or features suggesting sepsis

Early Assessment Matters When Appendicitis Is Suspected

Symptoms, examination, laboratory findings and appropriate imaging can be assessed together to determine whether surgery or selected non-operative treatment is appropriate.

Frequently Asked Questions

What is appendicitis?
Appendicitis is inflammation of the appendix, a small organ attached to the first part of the large intestine. It may remain uncomplicated or progress in some patients to perforation, abscess or peritonitis.
Where does appendicitis pain begin?
Classically, appendicitis pain begins around the navel or central abdomen and moves towards the right lower abdomen over several hours. Because the position of the appendix varies, not every patient develops the same pain pattern.
Can ultrasound diagnose appendicitis?
Ultrasound can be useful, particularly in children and younger patients, but the appendix cannot always be visualised. CT or MRI may be required depending on the clinical situation.
Can appendicitis be treated with antibiotics?
Antibiotic-only treatment can be an option for selected patients with uncomplicated acute appendicitis. However, recurrence or later appendectomy may occur, so this approach is not suitable for every patient.
Does appendicitis always require surgery?
No. Appendectomy is the definitive and standard surgical treatment, but selected patients with uncomplicated appendicitis may be considered for non-operative antibiotic treatment. The decision depends on disease severity and the patient's clinical condition.
What is an appendectomy?
An appendectomy is the surgical removal of the appendix. In suitable patients, the operation is generally performed using a laparoscopic or keyhole approach.
What happens if appendicitis perforates?
If the appendix perforates, infected material can spread into the abdomen and cause serious complications including an abscess, peritonitis or sepsis. Suspected appendicitis should therefore be assessed promptly.
Can you live normally without an appendix?
The appendix may have roles related to intestinal immunity and the microbiome, but it is not essential for life. People generally live normally after appendectomy.
Academic Hospital note: Appendicitis cannot be diagnosed from the location of pain alone. Examination, laboratory findings and appropriate imaging should be assessed together. Appendectomy remains the standard surgical treatment, while selected uncomplicated cases may also be considered for non-operative treatment. You can book an appointment.

References

  1. Academic Hospital. Appendicitis
  2. World Society of Emergency Surgery. Diagnosis and Treatment of Acute Appendicitis: 2025 Edition of the WSES Jerusalem Guidelines
  3. Society of American Gastrointestinal and Endoscopic Surgeons. Guideline for the Diagnosis and Treatment of Appendicitis