Gastroenteritis

Gastroenteritis (also known as gastro , gastric flu , tummy bug in the United Kingdom, and stomach flu , although unrelated to influenza ) is inflammation of the gastrointestinal tract, involving both the stomach and the small intestine(see also and resulting in acute diarrhea. The inflammation is caused most often by infection with certain viruses, less often by bacteria or their toxins, parasites, or adverse reaction to something in the diet or medication. Worldwide, inadequate treatment of gastroenteritis kills 5 to 8 million people per year, and is a leading cause of death among infants and children under 5.

At least 50% of cases of gastroenteritis as foodborne illness are due to norovirus. Another 20% of cases, and the majority of severe cases in children, are due to rotavirus. Other significant viral agents include adenovirus and astrovirus.

Different species of bacteria can cause gastroenteritis, including Salmonella, Shigella , Staphylococcus, Campylobacter jejuni, Clostridium, Escherichia coli, Yersinia, and others. Some sources of the infection are improperly prepared food, reheated meat dishes, seafood, dairy, and bakery products. Each organism causes slightly different symptoms but all result in diarrhea. Colitis, inflammation of the large intestine, may also be present.

Risk factors include consumption of improperly prepared foods or contaminated water and travel or residence in areas of poor sanitation. It is also common for river swimmers to become infected during times of rain as a result of contaminated runoff water. The incidence is 1 in 1,000 people.

Gastroenteritis can be classified as either viral or bacterial.

Symptoms and signs

Gastroenteritis often involves stomach pain or spasms (sometimes to the point of being incapacitated), diarrhea and/or vomiting, with noninflammatory infection of the upper small bowel, or inflammatory infections of the colon.

It usually is of acute> onset, normally lasting 1–6 days, in some cases even longer and is self-limiting.

• Nausea and vomiting
• Diarrhea
• Loss of appetite
• Abdominal pain
• Abdominal cramps
• Bloody stools (dysentery - suggesting infection by amoeba, Campylobacter, Salmonella, Shigella or some pathogenic strains of Escherichia coli)
• Fainting and Weakness

The main contributing factors include poor feeding in infants. Diarrhea is common, and may be followed by vomiting. Viral diarrhea usually causes frequent watery stools, whereas blood stained diarrhea may be indicative of bacterial colitis . In some cases, even when the stomach is empty, bile can be vomited up.

A child with gastroenteritis may be lethargic, suffer lack of sleep, run a low fever, have signs of >dehydration (which include dry mucous membranes), tachycardia, reduced skin turgor , skin color discoloration, sunken fontanelles, sunken eyeballs, darkened eye circles, glassy eyes, poor perfusion and ultimately shock.

Symptoms occur for up to 6 days on average. Given appropriate treatment, bowel movements will return to normal within a week after that.