enteritis

Enteritis is inflammation of the small intestine, which can be acute or chronic. It commonly presents with diarrhea, abdominal pain or cramping, nausea and vomiting, and sometimes fever. Inflammation disrupts intestinal absorption and increases secretion, leading to watery stools and dehydration in some cases.

Causes include infectious agents such as viruses (notably norovirus and rotavirus), bacteria (for example Salmonella, Campylobacter, Shigella, and certain Escherichia coli strains), and parasites (such as Giardia). Noninfectious causes include medication-induced enteritis (for instance, NSAIDs or antibiotic-associated dysbiosis), inflammatory diseases affecting the small bowel (such as Crohn disease), ischemia, radiation, and autoimmune or allergic processes.

Diagnosis is based on clinical presentation and examination. Stool testing may identify infectious pathogens in many cases. Laboratory tests can include a complete blood count, electrolytes, and renal function to assess dehydration and systemic involvement. Imaging or endoscopy is reserved for cases with alarm features, severe dehydration, persistent symptoms, or suspected complications.

Management focuses on hydration and supportive care. Oral rehydration solutions are preferred when possible; IV fluids may be required for significant dehydration. Antiemetics can help with nausea. Antibiotics are reserved for specific bacterial infections or high-risk patients and should be guided by local guidelines. Prevention involves good hand hygiene, safe food and water practices, and vaccination against rotavirus, particularly to protect children.

Prognosis is typically favorable in healthy individuals, with most cases resolving within days to weeks; risk of complications is higher in young children, older adults, and immunocompromised persons.