Further evaluation can be done to ensure there isn't any biliary obstruction.
An ultrasound can be done to image the liver and gallbladder. If there is suspicion about the biliary tree, you can consider an MRCP.
If the tests remain negative, there are benign causes of an isolated bilirubin level. Gilbert's disease would be one cause.
These questions should be discussed with your personal physician.
This answer is not intended as and does not substitute for medical advice - the information presented is for patients education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
www.kevinmd.com