CT of the abdomen and pelvis is often one of the first tests used to evaluate abdominal and pelvic pain. CT is effective in detecting many types of infectious and inflammatory conditions in the abdomen and pelvis. It can also be used as part of the workup for other complaints, such as gastrointestinal bleeding, weight loss, bloating, unexplained fever, or trauma. Your doctor may also order this test to further investigate potential abnormalities found on other modalities, such X-ray or ultrasound. CT of the abdomen and pelvis is also used to stage and follow treatment response for many types of cancers.