- The appendix is a narrow tubular pouch attached to the intestines.
- When the appendix is blocked, it becomes inflamed and results in appendicitis.
- If the blockage continues, the inflamed tissue becomes infected with bacteria and begins to die from a lack of blood supply, which finally results in the rupture of the appendix (perforated or ruptured appendix).
- An American Journal of Epidemiology study in 1990 found that appendicitis was a common condition affecting approximately 6.7% of females and 8.6% of males. In the U.S. 250,000 cases of appendicitis are reported annually.
- Individuals of any age may be affected, with the highest incidence occurring in the teens and twenties; however, rare cases of neonatal and prenatal appendicitis have been reported.
- Increased vigilance in recognizing and treating potential cases of appendicitis is critical in the very young and elderly, as this population has a higher rate of complications.
- Appendicitis is the most common pediatric condition requiring emergency abdominal surgery.
There is no clear cause of appendicitis. Fecal material is thought to be one possible cause of obstruction of the appendix. Bacteria, viruses, fungi, and parasites can result in infection, leading to the swelling of the tissues of the appendix wall. The various infecting organisms include
Yersinia species, adenovirus, cytomegalovirus, actinomycosis, Mycobacteria species, Histoplasma species, Schistosoma species,
pinworms, and Strongyloides stercoralis.
Swelling of the tissue from inflammatory bowel disease such as
Crohn's disease also may cause appendicitis.
Appendicitis is not a hereditary disease and is not transmittable from person to person.
Appendicitis Picture - Inflammation of the Appendix
Appendicitis Symptoms and Signs
Appendicitis typically begins with a vague pain in the middle of the abdomen often near the navel or "belly button" (umbilicus). The pain slowly moves to the right lower abdomen (toward the right hip) over the next 24 hours. In the classic description, abdominal pain may be accompanied with nausea, vomiting, lack of appetite, and fever. Fewer than half of people who develop appendicitis have all the symptoms. More commonly, people with appendicitis have any combination of these symptoms.
- Symptoms of appendicitis may take 4 to 48 hours to develop. During this time, a person may have varying degrees of loss of appetite, vomiting, and abdominal pain. The person may have constipation or diarrhea, or there may be no change in bowel habits.
- Early symptoms are often hard to separate from other conditions including gastroenteritis (an inflammation of the stomach and intestines). Many people admitted to the hospital for suspected appendicitis leave the hospital with a diagnosis of gastroenteritis; initially, true appendicitis is often misdiagnosed as gastroenteritis.
- Children and the elderly often have fewer symptoms, or cannot adequately describe their symptoms, which makes their diagnosis less obvious and the incidence of complications more frequent.
Most people with appendicitis have classic symptoms that a doctor can easily
identify. The main symptom of appendicitis is abdominal pain.
The abdominal pain usually
- occurs suddenly, often causing a person to wake up at night
- occurs before other symptoms
- begins near the belly button and then moves lower and to the right
- is new and unlike any pain felt before
- gets worse in a matter of hours
- gets worse when moving around, taking deep breaths, coughing, or sneezing
Other symptoms of appendicitis may include
- loss of appetite
- constipation or diarrhea
- inability to pass gas
- a low-grade fever that follows other symptoms
- abdominal swelling
- the feeling that passing stool will relieve discomfort
When to Seek Medical Care
Call a doctor if there are acute symptoms of middle/lower or right/lower
abdominal pain with fever and/or vomiting.
If symptoms of abdominal pain continue for more than four hours, an urgent medical evaluation should be
performed at the doctor's office or a hospital's emergency department.
Appendicitis is diagnosed by the classic symptoms of appendicitis and physical examination (the
doctor's examination of
the patient's abdomen).
- Lab work: Although no blood test can confirm appendicitis, a blood sample is sent for laboratory analysis to check the
white blood cell count, which is typically elevated in
an individual with appendicitis. However, normal levels can be present with appendicitis, and elevated levels can be seen with other conditions. A
urinalysis may be ordered to exclude
urinary tract infection (or pregnancy) as the cause of the
- Imaging tests: Imaging tests are ordered when the diagnosis is not
readily apparent. A CT scan of the abdomen and pelvis
assist in evaluating abdominal pain suspected of being caused by appendicitis. Ultrasound scanning is commonly used in small children to test for appendicitis
to avoid exposing the child to radiation from CT scans.
Other conditions that cause abdominal pain may mimic the symptoms of
appendicitis making the diagnosis more difficult. These conditions include
kidney stones, urinary tract infections, hernias, gallstones and gallbladder
problems, colitis, diverticulitis, and ovarian or testicular problems.
Appendicitis can not be treated at home. If you suspect you have appendicitis, see your doctor or go to an emergency department.
Appendicitis Self-Care at Home
There is no home care for appendicitis. If appendicitis
is suspected, contact a doctor or go to an emergency department. Avoid eating
or drinking as this may complicate or delay surgery. If you are thirsty, you may
rinse your mouth with water. Do not use laxatives, antibiotics, or pain medications because these may cause delay in diagnosis
that increases the risk of rupture of the appendix or masks the symptoms, making diagnosis more difficult.
Appendicitis Surgery (Appendectomy)
The best treatment for appendicitis is surgery to remove the appendix (appendectomy)before the appendix ruptures. While awaiting surgery, the patient will be given IV fluids to keep hydrated. The patient will not be allowed to eat or drink because doing so may cause complications with the anesthesia during surgery.
Surgery is commonly performed via laparoscopy, a minimally invasive procedure where small "keyhole" incisions are made in the abdomen and the appendix is removed with the assistance of a small camera guided by the surgeon. In some cases it may be necessary to do an open abdominal procedure to remove the appendix.
Occasionally, surgery for appendicitis reveals a non-inflamed appendix (negative appendectomy), with high rates in infants, the elderly, and young women. The use of imaging studies (CT scans, ultrasounds) has reduced the negative appendectomy rate to 7% to 12%. The difficulty in making a definite diagnosis of this medical problem and the risk of missing an acutely inflamed appendix, and the patient becoming very ill due to perforation makes a certain rate of misdiagnosis inevitable. Women in particular have a high rate of negative appendectomy as ovarian and uterine problems make the diagnosis more difficult. CT scanning prior to surgery has decreased this percentage to closer to 7% to 8% in women.
After an uncomplicated appendectomy, recovery time can vary from 2 to 6 weeks. The individual may gradually resume a normal diet with restriction in physical activity for at least two to four weeks. The
doctor will inspect the incision the following week to look for possible wound infection.
There is no way of predicting when appendicitis will occur or prevent it from
There are no proven risk factors for appendicitis. It has been suggested that
potential risk factors may include a diet low in fiber and high in sugar, family
history, and infection.
- With uncomplicated appendicitis, most people recover with no long-term
- If the appendix ruptures, there is a greater risk of complications, including death. This increase in risk generally is found in the very young, elderly, and those with weakened immune systems, including
people with diabetes.
- Whether a perforated appendix is a significant risk for
infertility has not been well established. Some experts recommend that this be considered in young women who might be at risk.
Stump appendicitis is a rare condition where a small amount of remaining appendix tissue from a previous appendectomy becomes inflamed. About 1/10 of 1% of patients who had appendectomy developed stump appendicitis, in one retrospective study. Symptoms are similar to the original appendicitis, with right lower quadrant pain being the most common symptom.
Reviewed on 11/17/2017
Medically reviewed by John A. Daller, MD; American Board of Surgery with subspecialty certification in surgical critical care
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National Digestive Diseases Information Clearinghouse. Appendicitis.
Rao, P,M. et al. Introduction of appendiceal CT: impact on negative appendectomy and appendiceal perforation rates. Ann Surg. 1999 March; 229(3): 344–349.
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UpToDate. Acute appendicitis in children: Management.