How is the cause and site of rectal bleeding determined?
Accurately diagnosing the location and the cause of rectal bleeding is important for directing treatment. Diagnosis with rectal bleeding relies on the history and physical examination, anoscopy, flexible sigmoidoscopy, colonoscopy, radionuclide scans, angiograms, and blood tests. History and physical examination The age of the patient may offer an important clue to the cause of rectal bleeding. For example, moderate to severe rectal bleeding in teenagers and young adults is more likely to come from a Meckel’s diverticulum. Moderate or severe rectal bleeding among older individuals is more likely to be due to diverticulosis or angiodysplasias. Mild rectal bleeding in an adult with prior abdominal radiation treatment may be due to radiation proctitis. The presence or absence of other symptoms also may provide important clues. Bleeding from diverticulosis, angiodysplasias, and Meckel’s diverticula are usually not associated with abdominal or rectal pain. Rectal bleeding from ischemic coli
