4 Stages of Appendicitis: Symptoms, Diagnosis, Treatment

The early inflammation stage, also known as simple or catarrhal appendicitis, happens when something blocks the appendix, such as fecalith (a small piece of poop), causing it to swell. At this stage, there is no infection or rupture of the appendix. Symptoms may not be noticeable, but can include:

• Slight fever
• Mild pain around the belly button
• Nausea
• Abdominal pain that moves to the lower right side
• Pain that gets worse with movement or coughing

This stage can last several hours, with symptoms typically worsening over 12-24 hours. About 75% of people seek medical help within 24 hours of symptoms. Early treatment may involve intravenous (IV) antibiotics and pain medicines. With rapid intervention, the outlook is very good. However, appendicitis returns about 20% of the time.

In the phlegmonous or suppurative stage, inflammation worsens due to continued blockage. This causes bacteria to spread into the appendix wall, leading to infection and the formation of abscesses (small pockets of pus).

Stage 2 involves more severe symptoms that disrupt daily life, such as:

• Constipation
• Higher fever
• Increased belly pain
• Nausea
• Vomiting
• Sharp pain in the lower right abdomen

At this stage, the infection may spread to nearby organs, increasing the risk of complications. Hospitalization is often necessary for pain management, antibiotics, and surgery. Prompt treatment can lead to a positive recovery.

Gangrenous appendicitis happens when severe inflammation cuts off blood flow to the appendix, causing necrosis (tissue death). As the tissue decays, it turns purple, green, or black. Symptoms include:

• Fast heart rate
• High fever
• Nausea
• Vomiting
• Severe abdominal pain

Without immediate treatment, the appendix can rupture, leading to widespread infection. You will need emergency surgery to remove dead tissue and prevent complications. Some people stay in the hospital for several days to continue IV antibiotics. While the risk of complications is higher at this stage, you can recover with timely treatment.

Perforated appendicitis is when your appendix ruptures, releasing pus and bacteria into your abdomen. The appendix can burst within 24 hours or less of symptoms starting. The leakage can cause an abscess. This is the body’s way of trying to contain the infection so it doesn’t spread. Ruptures can lead to peritonitis, an infection that spreads to the abdominal lining.

Symptoms of a ruptured appendix include:

• Confusion
• Fast heartbeat 
• High fever
• Involuntary muscle tightening (especially with peritonitis)
• Low blood pressure
• Severe belly pain
• Weakness
• Temporary relief of pain after rupture

Complications

Stage 4 requires emergency surgery. Recovery time depends on your infection’s severity. You may need intensive care to manage complications like:

• Fistulas (abnormal connections between the intestines and other organs)
• Infections or blood clots in the veins around the liver
• Intestinal blockage
• Sepsis (a dangerous spread of infection throughout the body)
• Swelling of the kidneys due to blocked urine flow

Providers sometimes describe appendicitis as acute, uncomplicated, complicated, or chronic.

Acute

Acute appendicitis is the sudden inflammation of the appendix. Symptoms often include:

• Abdominal swelling
• Sharp pain starting near the navel and shifting to the lower right abdomen
• Nausea
• Vomiting
• Fever
• Constipation or diarrhea
• Elevated white blood cell (WBC) count

Prompt appendectomy (surgical removal of the appendix) is usually required to prevent complications.

Uncomplicated Acute Appendicitis

Uncomplicated appendicitis refers to acute inflammation of the appendix that has not yet caused complications like rupture, abscess, or peritonitis.

The standard treatment is appendectomy. Alternatively, some adults (and less commonly, children) may undergo a 10-day regimen of broad-spectrum antibiotics. With antibiotics only, the recurrence rate of appendicitis within a year is about 15-41%.

Complicated Acute Appendicitis

Complicated appendicitis occurs when acute appendicitis advances to a more severe stage, often involving rupture. This leads to peritonitis or abscesses. Symptoms may include more intense and widespread abdominal pain, high fever, chills, and signs of sepsis, such as rapid heart rate and low blood pressure.

Complicated appendicitis is a medical emergency requiring immediate intervention. Treatment involves appendectomy and may include drainage of abscesses and extensive antibiotic therapy to manage infection and prevent further complications.

Chronic Appendicitis

Chronic appendicitis is long-term, low-grade inflammation of the appendix. It occurs in only about 1% of cases. It causes mild to moderate abdominal pain and discomfort, often occurring in intermittent flare-ups.

Pain typically lasts more than 48 hours. You may experience symptoms for weeks, months, or even years before a correct diagnosis is made. Treatment involves appendectomy to prevent serious complications.

Healthcare providers diagnose appendicitis using medical history, physical exams, and screening tests. These help assess the stage of the inflammation, check for complications, and guide appropriate treatment.

Physical Exam

During a physical exam, a provider will gently press the abdomen to check for tenderness. This can help assess the severity of pain and determine if it’s consistent with appendicitis.

Providers look for the following signs of appendix inflammation or irritation:

• Involuntary guarding: Automatic tightening of stomach muscles
• Obturator sign: Pain in the lower right abdomen when you lie on your back and rotate your bent right leg inward and outward at the hip
• Psoas sign: Pain in your lower right abdomen when you lie on your left side and stretch your right leg backward
• Rebound tenderness: Pain when the provider quickly applies and releases pressure
• Rovsing’s sign: Pain in the lower right side of your abdomen when the provider presses on your left side
• Tenderness at McBurney’s point: Pain in the lower right abdomen when the provider presses there

Blood and Urine Tests

Providers may order tests to help confirm an appendicitis diagnosis, such as:

• C-reactive protein (CRP): This test measures CRP levels in your blood. High CRP levels suggest inflammation.
• Complete blood count (CBC): This test measures blood components like white blood cells (WBC). About two-thirds of people with appendicitis have a high WBC count, indicating an infection. A WBC count over 17,000 typically indicates later-stage appendicitis.
• Urinalysis (UA): This test examines urine for signs of infection, blood, or other abnormalities. It helps rule out urinary tract infections (UTIs) or pregnancy, which can cause symptoms similar to appendicitis.
• Pregnancy test: An ectopic (outside of the uterus) pregnancy can cause abdominal pain similar to that of appendicitis. Pregnancy tests help rule out this potentially life-threatening condition.

Imaging Tests

The following imaging tests take pictures of the appendix and surrounding areas to help diagnose and stage appendicitis: 

• Ultrasound: An ultrasound uses sound waves to create images. It’s often the first imaging test used to diagnose appendicitis because it doesn’t use radiation. However, it is less accurate than CT or MRI.
• Computed tomography (CT) scan: A CT scan is a fast, accurate tool for diagnosing appendicitis. It provides more detailed images of the abdomen, but it uses a small amount of radiation. They may use it severe cases or if an ultrasound is inconclusive.
• Magnetic resonance imaging (MRI): An MRI uses magnets and radio waves to create detailed images without radiation. MRIs are accurate but expensive and take longer than CT scans.

Some cases of appendicitis can be treated with antibiotic therapy. In later stages, an appendectomy is typically necessary to keep the infection from spreading. Surgeons usually prefer laparoscopic surgery, which involves smaller cuts and allows for a quicker recovery than open abdominal surgery.

Appendectomy rarely causes lasting damage. The appendix does not perform any essential bodily tasks. Unlike with the removal of other organs, you won’t need to change anything in your daily life after an appendectomy.

The stages of appendicitis range from minor inflammation to severe rupture. Initial symptoms include mild abdominal discomfort, but the pain can progress rapidly within hours. Treatment may involve antibiotics, pain management, and emergency surgery. As the condition progresses, symptoms worsen, requiring immediate surgical intervention.

Understanding the stages of appendicitis is crucial for effective treatment. Early symptom recognition can prevent the condition from advancing to more severe stages and help avoid complications.  If you or a loved one experiences signs of appendicitis, seek medical care right away.