[1] Related diseases of the gastrointestinal (GI) system (including gastritis, gastroenteritis, colitis, and enterocolitis) may involve inflammation of the stomach and large intestine.

[2] Signs and symptoms of enteritis are highly variable and vary based on the specific cause and other factors such as individual variance and stage of disease.

Symptoms may include abdominal pain, cramping, diarrhea,[3] dehydration, fever, nausea, vomiting, and weight loss.

[10] Other common causes of infectious enteritis include bacteria such as Shigella and E. coli, as well as viruses such as adenovirus, astrovirus, and calicivirus.

[18] Surgical treatment is usually required due to the likelihood of stenosis or complete occlusion of the small intestine.

[citation needed] Inflammation of the gastrointestinal tract is common after treatment with radiation therapy to the abdomen or pelvis.

Delayed radiation enteritis is a chronic disease which has a complex pathogenesis involving changes in the majority of the intestinal wall.

In particular, Campylobacter, Shigella, Salmonella and many other bacteria induce acute self-limited colitis, an inflammation of the lining of the colon which appears similar under the microscope.

[6] A medical history, physical examination and tests such as blood counts, stool cultures, CT scans, MRIs, PCRs, colonoscopies and upper endoscopies may be used in order to perform a differential diagnosis.

[11] Autoimmune causes of enteritis such as Crohn's disease require significant chronic treatment to avoid nutritional deficiencies, cancer, bacterial overgrowth, and other complications.

[7] The word enteritis (/ˌɛntəˈraɪtɪs/) uses combining forms of entero- and -itis, both Neo-Latin from Greek, respectively from ἑντερον (enteron, small intestine) and -ιτις (-itis, inflammation).