👉 Ileitis is a type of gastrointestinal (GI) infection that can occur in the small intestine or colon. It usually starts with abdominal pain, nausea and vomiting, but it can also include diarrhea, fever, and other symptoms. The exact cause of ileitis is not fully understood, but it is often due to an inflammation of the lining of the intestines, which can be caused by a variety of factors such as bacteria, viruses or parasites. Treatment for ileitis usually involves rest, pain