Appendicitis is inflammation and infection of the appendix.
- Appendicitis seems to develop when the appendix becomes blocked either by hard fecal material (called a fecalith) or swollen lymph nodes in the intestine that can occur with various infections.
- Pain typically starts around the bellybutton (umbilicus) and then moves to the right lower abdomen but it may also be widespread and it may make children irritable or listless.
- Diagnosis is challenging and may require blood tests, ultrasonography, computed tomography, magnetic resonance imaging, or laparoscopy.
- An inflamed appendix is removed surgically.
(For adults, see Appendicitis.)
Appendicitis seems to develop when the appendix becomes blocked either by hard fecal material (fecalith) or swollen lymph nodes in the intestine, which can occur with various infections. In either case, the appendix swells, and bacteria in it grow. Rarely, swallowed foreign objects and infections with certain parasitic worms (such as strongyloidiasis) can also cause appendicitis.
Complications of appendicitis
If appendicitis is unrecognized or untreated, the appendix can rupture, creating a pocket of infection outside the intestine (abscess) or spilling contents of the intestines into the abdominal cavity, causing a serious infection (peritonitis). In about 25% of children with appendicitis, the appendix has already ruptured by the time they arrive at the hospital.
Appendicitis almost always causes pain. The pain may start in the middle of the abdomen around the bellybutton and then move to the lower right area of the abdomen. Pain, particularly in infants and children, may be widespread rather than confined to the right lower portion of the abdomen. Younger children may be less able to identify a specific location for the pain and may be very irritable or listless. The abdomen is usually tender when the doctor pushes on it, usually in the area over the appendix.
After the pain has begun, many children begin vomiting and do not want to eat. A low-grade fever (100 to 101° F [37.7 to 38.3° C]) is a common symptom. This pattern is different from that in children who have viral gastroenteritis, in whom vomiting typically occurs first, and pain and diarrhea develop later. Significant diarrhea is not common among children who have appendicitis.
- Sometimes other imaging tests
- Sometimes laparoscopy
The diagnosis of appendicitis in children can be challenging for many reasons. Many disorders can cause similar symptoms, including viral gastroenteritis, Meckel diverticulum, intussusception, and Crohn disease. Often, children do not have typical symptoms and physical examination findings, particularly when the appendix is not in its usual position in the right lower part of the abdomen.
Most often, doctors do ultrasonography, which does not expose the child to radiation. If the diagnosis is not clear, doctors may do computed tomography (CT) or magnetic resonance imaging (MRI). Doctors who suspect appendicitis usually give fluids and antibiotics by vein while waiting for results of blood tests and imaging tests.
If the diagnosis is not clear, doctors may do laparoscopy, in which a small viewing scope is put through the wall of the abdomen to look inside. If appendicitis is found during laparoscopy, doctors can remove the appendix using the laparoscope. Alternatively, especially in children whose symptoms and examination findings are not typical of appendicitis, doctors may simply do repeated physical examinations. Seeing whether the symptoms and tenderness are getting worse or better with time may help doctors decide whether appendicitis is present.
With early treatment, the overall prognosis for children who have appendicitis is very good. Less than 1% of treated children die of appendicitis.
If children are not treated until the appendix has ruptured, which occurs most commonly in children under 3 years of age, the prognosis is worse. In young children, the mortality rate may be as high as 80%. Rupture is less common among school-aged children, and their mortality rate is 10 to 20%. About 10 to 25% of children who have surgery for a ruptured appendix have complications.
If children are not treated, appendicitis rarely can go away on its own. Usually, however, untreated appendicitis progresses and causes peritonitis, an abdominal abscess, and sometimes death.
- Antibiotics by vein
The best treatment for appendicitis is surgical removal of the inflamed appendix (appendectomy). Before surgery, doctors give antibiotics by vein, which decreases the risk of complications. Recently, doctors have been studying whether giving antibiotics without doing surgery can treat appendicitis. Although antibiotic-only treatment seems to work in some children, others still need an operation. Doctors in the United States still recommend surgery.
Appendectomy is fairly simple and safe, requiring a hospital stay of 2 to 3 days in children who have no complications, such as a ruptured appendix. If the appendix has ruptured, the doctor removes it and may wash out the abdomen with fluid, give antibiotics for several days, and watch for complications, such as infection and bowel blockage.
About 10 to 20% of the time, surgeons discover a normal appendix while doing an appendectomy. This finding is not considered a medical error because the consequences of delaying surgery when appendicitis is suspected are serious. When the appendix is found to be normal, the surgeon looks in the abdomen for another cause of the pain. The doctor usually removes a normal appendix so that the child never develops appendicitis.
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