Enteritis is inflammation of the small intestine.

Enteritis is usually caused by eating or drinking substances contaminated with bacteria or viruses. The germs settle in the small intestine and causes inflammation and swelling which may lead to abdominal pain, cramping, diarrhea, fever, and dehydration.

Enteritis may also be a result of:

• An autoimmune condition, such as Crohn's disease
• Certain drugs, including ibuprofen, naproxen sodium, and cocaine

The inflammation frequently also involves the stomach (gastritis) and large intestine (colitis).

Risk factors include recent family illness with intestinal symptoms, recent travel, or exposure to untreated or contaminated water.

Types of enteritis include:

• Bacterial gastroenteritis
• Campylobacter enteritis
• E. coli enteritis
• Food poisoning
• Radiation enteritis
• Salmonella enteritis
• Shigella enteritis
• Staph aureus food poisoning

The symptoms may begin soon after infection, or there can be a delay of several days.

• Abdominal pain
• Diarrhea - acute and severe
• Loss of appetite
• Vomiting - rare

A stool culture may be done to determine the specific type of infection. A stool sample may reveal specific toxins. An upper endoscopy is sometimes needed.