Appendicitis

Appendicitis is an inflammation of the appendix, a small finger-shaped pouch attached to the large intestine. This condition causes pain that typically begins around the belly button and moves to the lower right side of the abdomen. Without prompt treatment, the appendix can burst, leading to serious complications.

Table of contents

• What is Appendicitis?
• Location and Function of the Appendix
• What Causes Appendicitis?
• How Common is Appendicitis?
• Symptoms of Appendicitis
• How is Appendicitis Diagnosed?
• Treatment Options
• Complications of Untreated Appendicitis
• When to Seek Medical Help

What is Appendicitis?

Appendicitis is an inflammation of the appendix, which is a finger-shaped pouch that sticks out from the colon on the lower right side of the belly, also called the abdomen^[1]. When the appendix becomes inflamed and filled with pus, it causes pain and requires medical attention^[1].

There are two main types of appendicitis. Acute appendicitis is the most common form, where symptoms start suddenly and get worse quickly within a few hours^[4]. Chronic appendicitis is much rarer, occurring when the appendix is inflamed but symptoms are usually milder and the pain can return over weeks, months, or even years^[4]. However, any type of appendicitis is serious and requires medical care^[9].

• Large intestine
• Colon
• Abdomen

Location and Function of the Appendix

The appendix is a small, tube-shaped organ attached to the large intestine. It is located in the lower-right area of the abdomen, near where the small intestine attaches to the large intestine^[2]. The appendix is about 3 and a half inches long and shaped like a finger^[4].

A healthy appendix makes mucus that drains into the large intestine^[7]. The appendix has specialized tissue that can make antibodies, but no one is completely sure what its complete function is^[3]. The good news is that you can live just fine without it^[4].

What Causes Appendicitis?

Appendicitis happens when the appendix becomes blocked, often by dried poop, a foreign body, or cancer^[4]. Blockage may also result from infection, since the appendix can swell in response to any infection in the body^[4].

Several specific conditions can lead to appendicitis. Appendix stones, which are old poop that has dried up and hardened, can get stuck in the opening of the appendix^[4]. Since these stones carry bacteria and can trap other bacteria inside the appendix, they are likely to cause inflammation^[4].

Another cause is lymphoid hyperplasia, where the lymph nodes start to produce extra cells in response to a virus or infection^[4]. Since the appendix has lymphatic tissue, it might react by swelling, even if it’s not the source of the infection^[4]. That swelling can cause a blockage that leads to an infection.

Other causes include colitis (inflammation of the large intestine), tumors growing inside the appendix, parasites such as pinworms blocking the appendix, and in some cases, cystic fibrosis^[4][7]. When the appendix becomes blocked, the mucus it makes builds up and hardens, stopping normal blood flow through the appendix and causing it to become inflamed and swell^[7].

How Common is Appendicitis?

In the United States, appendicitis is the most common cause of acute abdominal pain requiring surgery. About 5 to 9 out of every 100 people develop appendicitis at some point^[2]. In the United States alone, approximately 300,000 hospital visits are reported annually related to appendicitis^[3].

Appendicitis is slightly more common among males than females^[2]. It happens most often in people in their teens and 20s, but it may occur in people of any age, including older adults^[2]. Although anyone can develop appendicitis, most often it happens in people between the ages of 10 and 30^[1]. Appendicitis is rare in children younger than 2^[4].

Symptoms of Appendicitis

The most common symptoms of appendicitis are abdominal pain, nausea, and loss of appetite^[9]. The classic history of appendicitis includes loss of appetite and pain around the belly button followed by nausea, then pain moving to the right lower part of the abdomen, and vomiting^[6]. However, this classic presentation occurs in only about 50% of cases^[6].

In the typical presentation, abdominal pain begins in the middle of the abdomen, around the belly button^[9]. It may hover or come and go for several hours. Eventually, the pain intensifies, and nausea and vomiting develop^[9]. Several hours later, the nausea passes, and the pain shifts to the lower right abdomen, where the appendix is located. The pain becomes more focused and continues to worsen^[9].

Additional symptoms may include:

• Pain that worsens with coughing, walking, or making other jarring movements^[1]
• Low-grade fever that may rise as the illness worsens^[1]
• Constipation or diarrhea^[1]
• Belly bloating and gas^[1]
• Feeling sick or generally unwell^[9]

The site of pain may vary depending on age and the position of the appendix^[1]. In pregnancy, the pain may seem to come from the upper belly because the appendix is higher during pregnancy^[1]. Kids, elderly adults, and those who are pregnant may be less likely to present with typical symptoms^[9].

If appendicitis is not treated quickly, the appendix can burst. If this happens, the pain may suddenly get better for a short time, but then severe pain that spreads to the whole abdomen usually follows^[16]. It may be very painful to move^[16].

How is Appendicitis Diagnosed?

To help diagnose appendicitis, a healthcare professional will likely take a history of symptoms and examine the abdomen^[8]. The doctor will talk to you about any other health problems you have had and ask questions about the symptoms you have, when they started, and what was happening before the pain began^[18].

During a physical exam, a healthcare professional may apply gentle pressure on the painful area. When the pressure is suddenly released, appendicitis pain will often feel worse^[8]. This is because of inflammation of the lining of the abdominal cavity, called the peritoneum^[8]. A care professional also may look for abdominal stiffness and a tendency to flex the abdominal muscles in response to pressure over the inflamed appendix, which is called guarding^[8].

Several tests may be used to diagnose appendicitis:

• Blood tests check for a high white blood cell count, which may mean there’s an infection^[8]
• Urine tests (also called urinalysis) make sure that a urinary tract infection or a kidney stone isn’t causing the pain^[8]
• Imaging tests may help confirm appendicitis or find other causes for pain. These tests may include an abdominal X-ray, an abdominal ultrasound, a CT scan, or an MRI^[8]

Because appendicitis can be hard to diagnose, sometimes doctors will try waiting a few hours to see how symptoms develop in hospital^[16]. It’s especially hard to tell in children, pregnant women, and older adults^[15].

Treatment Options

Appendicitis treatment usually involves surgery to remove the appendix. Before surgery, antibiotics to treat infection may be given^[8]. Treatment of appendicitis is usually antibiotics and, in most instances, surgery to remove the appendix^[1].

Surgery to remove the appendix is called an appendectomy. Appendectomy can be performed as open surgery using one abdominal cut about 2 to 4 inches long, which is called laparotomy^[8]. The surgery also can be done through a few small abdominal cuts using a thin tube with a camera, which is called keyhole surgery or laparoscopic surgery^[16]. The operation usually takes about an hour^[16].

Laparoscopic surgery is becoming increasingly common and generally leads to fewer complications, such as hospital-related infections, and it has a shorter recovery time^[10]. After examining your condition and past medical history, your surgeon will recommend the best method for you^[10].

Sometimes it’s possible to treat appendicitis with antibiotics rather than surgery^[16]. This may be recommended if the infection has not spread and surgery is high risk for you^[16]. Anyone who might have appendicitis is treated with antibiotics before surgery, and some people may improve with the antibiotics and not need surgery^[10]. However, surgery remains the standard treatment for appendicitis^[10].

Sometimes appendicitis causes a lump where part of the abdomen and bowel stick to the appendix, called an appendix mass. If this happens, you’ll usually need antibiotics first, and then surgery a few weeks later if you still have symptoms^[16].

Most people recover from appendicitis in 1 to 2 weeks. It may take longer if you had complications such as a burst appendix^[16].

Complications of Untreated Appendicitis

A burst appendix is a medical emergency^[9]. It spreads bacteria from inside the bowels throughout the abdominal cavity^[9]. This infection, called peritonitis, is a serious infection that can spread in the abdomen^[2]. The infection can then spread to the bloodstream, which can lead to life-threatening complications called sepsis^[9].

Another possible complication is an abscess of the appendix, called an appendiceal abscess^[2]. If left untreated or if the diagnosis is delayed, patients are at risk for appendiceal perforation, abscess formation, peritonitis, sepsis, and death^[3].

Kids younger than 5 have a much higher chance of having a burst appendix^[7]. This is because it is harder for them to describe their pain, harder for them to tell exactly where it hurts, and harder for them to sit still while a doctor checks them out^[7].

Because of the risk of serious complications, the standard treatment for appendicitis is to remove the appendix through surgery^[9]. The appendix isn’t an essential organ, and you won’t miss it^[9].

When to Seek Medical Help

Make an appointment with a healthcare professional if you or your child has symptoms of appendicitis^[1]. Terrible belly pain requires immediate medical attention^[1].

Call your doctor or nurse advice line now or seek immediate medical care if you have new or worse belly pain, or if the pain has become focused in one area of the belly^[15]. You should also seek care if you have nausea and don’t want to eat, are vomiting, have a fever, or cannot pass stools or gas^[15].

Call 999 or go to the emergency department if you or your child have severe pain in the abdomen, or confusion, blotchy or paler than usual skin, or difficulty breathing, as these could be signs of sepsis^[16]. Do not drive yourself to the emergency department. Ask someone to drive you or call for an ambulance^[16].

If you have symptoms of appendicitis, do not eat or drink anything, unless your doctor says it is okay. If you need surgery, it’s best to have an empty stomach^[15]. Do not take laxatives, as if you have appendicitis, they can make the appendix burst^[15].