Suspected appendicitis – Oral contrast is not required, but may be beneficial in extremely thin individuals (e.g. BMI < 18), or non-obese children.
Suspected diverticulitis – Oral contrast is not required
Unclear etiology – PO contrast is suggested by some experts in undifferentiated abd pain if the patient is very thin (e.g. < 120 pounds, BMI < 18); has had a Roux-en-Y gastric bypass; or has and inflammatory bowel disease that could produce a fistula