Gastroenteritis
Gastroenteritis is inflammation of the digestive tract that results in vomiting and diarrhea, sometimes accompanied by fever or abdominal cramps.
Gastroenteritis, sometimes called "stomach flu," is common in children (see Section 9, Chapter 122). Severe gastroenteritis results in dehydration and an imbalance of blood chemicals (electrolytes) because of a loss of body fluids in the vomit and diarrhea. Although gastroenteritis is rarely serious when proper medical care is available, in developing countries it can be extremely serious; millions of children die each year from diarrhea caused by gastroenteritis.
Causes
A wide variety of viruses, bacteria, and parasites cause gastroenteritis. However, viruses (such as rotavirus) are a far more common cause than are bacteria (such as Escherichia coli, Vibrio cholerae, Salmonella, or Shigella) or parasites (such as Giardia).
Children usually contract viral gastroenteritis from other children who have had or who have been exposed to it, such as those in childcare centers, schools, and other crowded settings. Viral gastroenteritis is generally spread from hand to mouth but can also be spread by sneezing and spitting. It spreads particularly easily because of the way children play--putting hands and fingers in and near their mouths and then touching toys and each other.
Children can contract bacterial gastroenteritis from eating mayonnaise, dairy products, meat, and other foods that have not been refrigerated. Improper preparation of food, especially undercooking, can lead to gastroenteritis. Gastroenteritis contracted in this way is sometimes called "food poisoning" (see Section 9, Chapter 122). Children can also contract bacterial or parasitic gastroenteritis from swallowing contaminated water, such as from wells, streams, and swimming pools, and while traveling in developing countries.
Occasionally, gastroenteritis results when children eat things they are not supposed to, such as plants and vitamin pills. Rarely, gastroenteritis results because of an allergic condition (eosinophilic gastroenteritis) or from contact with animals at petting zoos.
Symptoms and Diagnosis
Symptoms are usually a combination of vomiting, diarrhea, abdominal cramps, fever, and poor appetite. Usually, vomiting predominates early in the illness, and diarrhea becomes more prominent later, but some children have both at the same time. The stools may be bloody if certain bacteria are a cause. These symptoms eventually improve in children who drink enough fluids. Children who are slightly dehydrated are thirsty, but seriously dehydrated children become listless, irritable, or lethargic, and may stop drinking. Infants are much more likely than older children to develop these serious side effects.
A doctor bases the diagnosis of gastroenteritis on the child's symptoms and on the parents' responses to questions about what the child has been exposed to. Diagnostic tests are not usually needed because most forms of gastroenteritis get better by themselves over a short time. Doctors who suspect a bacterial or parasitic infection may order additional tests, including stool and blood tests, and ones that measure white blood cells. Dehydrated children require blood tests to help doctors guide treatment.
Prevention and Treatment
The best way to prevent gastroenteritis is to encourage children to wash their hands and to teach them to avoid improperly prepared or stored foods. A vaccine to prevent rotavirus infection is available in developing countries, but its use was discontinued in the United States because of side effects.
Once a child has gastroenteritis, parents should encourage the child to take frequent sips of water and to try to take small amounts of juices and soups, which contain both fluids and electrolytes. If gastroenteritis persists longer than 12 to 24 hours, or the child cannot hold down juice, electrolytes usually should be replaced. Electrolyte replacement is done at home using nonprescription electrolyte solutions available as powders and liquids in pharmacies and some grocery stores.
For a vomiting child, the parents wait about 10 minutes and give the child a few sips of a liquid. If the liquid is not vomited, the sips are repeated every 10 or 15 minutes, increasing the amount given to an ounce or two after an hour or so. These larger amounts can be given less often, about every hour. Liquids are absorbed very quickly, so if the child vomits more than 10 minutes after drinking, most of the fluid was absorbed and fluids should be continued. The amount of liquid to give a child depends on the child's age, but generally should be about 1½ to 2½ ounces of solution for each pound the child weighs in a 24-hour period. If the child's vomiting or diarrhea improves while drinking electrolyte solutions, parents may try resuming a diet of juice, soups, and soft foods like bananas and applesauce the next day.
Children with diarrhea but little vomiting are fed their normal diet, with extra liquid given to make up for the fluid lost in the diarrhea.
Danger signs include inability to keep down even sips of liquid or signs of dehydration (such as lethargy, dry mouth, lack of tears, and no output of urine for 6 hours or more). Such children should see the doctor immediately. Children without such signs should see the doctor if symptoms last more than 1 or 2 days. If the dehydration is severe the doctor may give the child intravenous fluids.
Antidiarrheal drugs such as loperamide are not usually recommended for children; there is reason to think these may slow the resolution of infection by preventing the body from flushing the virus, bacteria, or parasites out with the stools. Antibiotics are of no value when a viral infection is the cause of gastroenteritis. Doctors give antibiotics only for certain bacteria that are known to respond to these drugs. Antiparasitic drugs may be given for a parasitic infection.
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