Enteritis

Enteritis is inflammation of the small intestine.

Enteritis is most often caused by eating or drinking things that are contaminated with bacteria or viruses. The germs settle in the small intestine and cause inflammation and swelling.

Enteritis may also be caused by:

An autoimmune condition, such as Crohn disease
Crohn disease
Crohn disease is a disease where parts of the digestive tract become inflamed. It most often involves the lower end of the small intestine and the be...
Image

Read Article Now Book Mark Article
Certain medicines, including NSAIDS (such as ibuprofen and naproxen sodium) and cocaine
Damage from radiation therapy
Celiac disease
Tropical sprue
Whipple disease

The inflammation can also involve the stomach (gastritis) and large intestine (colitis).

Risk factors include:

Recent stomach flu among household members
Recent travel
Exposure to unclean water

Types of enteritis include:

Bacterial gastroenteritis
Bacterial gastroenteritis
Bacterial gastroenteritis occurs when there is a bacterial infection of your stomach or intestines.
Image

Read Article Now Book Mark Article
Campylobacter enteritis
Campylobacter enteritis
Campylobacter infection occurs in the small intestine from bacteria called Campylobacter jejuni. It is a type of bacterial food poisoning.
Image

Read Article Now Book Mark Article
E coli enteritis
E coli enteritis
E coli enteritis is swelling (inflammation) of the small intestine from Escherichia coli (E coli) bacteria. It is the most common cause of travelers...
Image

Read Article Now Book Mark Article
Food poisoning
Food poisoning
Food poisoning occurs when you swallow food or water that contains bacteria, parasites, viruses, or the toxins made by these germs. Most cases are c...
Image

Read Article Now Book Mark Article
Radiation enteritis
Radiation enteritis
Radiation enteritis is damage to the lining of the intestines (bowels) caused by radiation therapy, which is used for some types of cancer treatment....
Image

Read Article Now Book Mark Article
Salmonella enteritis
Salmonella enteritis
Salmonella enterocolitis is a bacterial infection in the lining of the small intestine that is caused by Salmonella bacteria. It is a type of food p...
Image

Read Article Now Book Mark Article
Shigella enteritis
Shigella enteritis
Shigellosis is a bacterial infection of the lining of the intestines. It is caused by a group of bacteria called Shigella.
Image

Read Article Now Book Mark Article
Staph aureus food poisoning
Non-bacterial infections such as viruses and protozoa

Symptoms

The symptoms may begin hours to days after you become infected. Symptoms may include:

Abdominal pain
Diarrhea -- acute and severe
Loss of appetite
Vomiting
Blood in the stool

Exams and Tests

Tests may include:

A stool culture culture or multiplex PCR to look for the type of infection. However, this test may not always identify the bacteria or other organisms causing the illness.
Stool culture
A fecal culture is a lab test to find organisms in the stool (feces) that can cause gastrointestinal symptoms and disease.
Image

Read Article Now Book Mark Article
A colonoscopy and/or upper endoscopy to look at the small intestine and to take tissue samples if needed.
Imaging tests, such as CT scan and MRI, if symptoms persist.

Treatment

Mild cases of enteritis often do not need testing or treatment.

Antidiarrheal medicine is sometimes used.

You may need rehydration with electrolyte solutions if your body does not have enough fluids.

You may need medical care and fluids through a vein (intravenous fluids) if you have diarrhea and cannot keep fluids down. This is often the case with young children.

If you take diuretics (water pills) or an ACE inhibitor and develop diarrhea, you may need to stop taking the medicines. However, do not stop taking any medicine without first talking to your health care provider.

You may need to take antibiotics.

People who have Crohn disease will often need to take anti-inflammatory medicines (not NSAIDs).

Outlook (Prognosis)

Symptoms most often go away without treatment in a few days in otherwise healthy people.

Possible Complications

Complications may include:

Dehydration
Long-term diarrhea

Note: In babies, the diarrhea can cause severe dehydration that comes on very quickly.

When to Contact a Medical Professional

Contact your provider if:

You become dehydrated.
Diarrhea does not go away in 3 to 4 days.
You have a fever over 101°F (38.3°C).
You have blood in your stool
You have severe belly pain

Prevention

The following steps may help prevent enteritis:

Always wash your hands after using the toilet and before eating or preparing food or drinks. You may also clean your hands with an alcohol-based product containing at least 60% alcohol.
Boil water that comes from unknown sources, such as streams and outdoor wells, before drinking it.
Use only clean utensils for eating or handling foods, particularly when handling eggs and poultry.
Cook food thoroughly.
Use coolers to store food that needs to stay chilled.

Open References

References

Fleckenstein JM. Approach to the patient with suspected enteric infection. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 262.

Lima AAM, Warren CA, Guerrant RL. Acute dysentery syndromes (diarrhea with fever). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 99.

Melia JMP, Sears CL. Infectious enteritis and proctocolitis. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 110.

Semrad CE. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 126.

Salmonella typhi organism - illustration
The causative agent of typhoid fever is the bacterium Salmonella typhi. (Image courtesy of the Centers for Disease Control and Prevention.)
Salmonella typhi organism
illustration
Yersinia enterocolitica organism - illustration
This picture shows the organism Yersinia enterocolitica. Yersinia organisms cause a wide range of disease but are most often associated with diarrhea or gastrointestinal symptoms. Yersinia infection is appearing with increased frequency in immunocompromised individuals. (Image courtesy of the Centers for Disease Control and Prevention.)
Yersinia enterocolitica organism
illustration
Campylobacter jejuni organism - illustration
Campylobacter jejuni infection causes cramping, diarrhea, abdominal pain and fever within 2 to 5 days after a person has been exposed to the organism. Campylobacter jejuni is one of the most common bacterial causes of diarrhea. Most cases of Campylobacter jejuni come from handling or ingesting raw or undercooked poultry meat. Although poultry and other birds are not affected by the bacterium, other animals can be. Therefore it is possible for a person to acquire the infection from contact with infected stool of an ill cat or dog. This is what Campylobacter organisms look like through a microscope. (Image courtesy of the Centers for Disease Control and Prevention.)
Campylobacter jejuni organism
illustration
Clostridium difficile organism - illustration
Clostridioides difficile is a bacterium commonly found in the intestinal tract but which, under the right circumstances, such as after or during antibiotics therapy, can be the cause of enterocolitis. (Image courtesy of the Centers for Disease Control and Prevention.)
Clostridium difficile organism
illustration
Digestive system - illustration
The esophagus, stomach, large and small intestine, aided by the liver, gallbladder and pancreas convert the nutritive components of food into energy and break down the non-nutritive components into waste to be excreted.
Digestive system
illustration
Esophagus and stomach anatomy - illustration
Food is swallowed and passes through the esophagus to the stomach, where the majority of digestion takes place.
Esophagus and stomach anatomy
illustration

A Closer Look

Self Care

Tests for Enteritis

Review Date: 6/11/2024

Health Content Provider

06/01/2025

A.D.A.M., Inc. is accredited by URAC, for Health Content Provider (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics. This site complied with the HONcode standard for trustworthy health information from 1995 to 2022, after which HON (Health On the Net, a not-for-profit organization that promoted transparent and reliable health information online) was discontinued.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- 2025 A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Health Library

Enteritis

Crohn disease

Gastritis

Colitis

Bacterial gastroenteritis

Campylobacter enteritis

E coli enteritis

Food poisoning

Radiation enteritis

Salmonella enteritis

Shigella enteritis

Symptoms

Exams and Tests

Stool culture

Treatment

Electrolyte

Intravenous

ACE inhibitor

Outlook (Prognosis)

Possible Complications

When to Contact a Medical Professional

Prevention

References

Salmonella typhi organism - illustration

Salmonella typhi organism

Yersinia enterocolitica organism - illustration

Yersinia enterocolitica organism

Campylobacter jejuni organism - illustration

Campylobacter jejuni organism

Clostridium difficile organism - illustration

Clostridium difficile organism

Digestive system - illustration

Digestive system

Esophagus and stomach anatomy - illustration

Esophagus and stomach anatomy