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Transcutaneous Bilirubin Measurement

What is transcutaneous bilirubin measurement?

Transcutaneous bilirubin (TcB) measurement is a way to find out how much bilirubin is in your child’s blood without using a needle. Bilirubin is a substance that is made each day as red blood cells break down.

Why is this test done?

Normally the liver removes bilirubin from the blood, but a newborn baby’s liver doesn’t do this well right after birth. When there is a lot of bilirubin in the blood, the skin and whites of the eyes get yellow. The yellow color of the skin and eyes is called jaundice. This test may be done to check bilirubin levels if your child has jaundice.

How do I prepare my child for this test?

Usually no preparation is needed for this test.

How is the test done?

Your healthcare provider will put a meter on your child’s head or chest. The meter will send a quick flash of light through the skin to measure the bilirubin level.

What does the test result mean?

Bilirubin levels normally vary with age. Your healthcare provider will assess you child’s bilirubin level based on how old your child is, how close your child was to his or her due date when born, and other factors.

Your child’s level of bilirubin may be higher than normal because:

  • Your child has jaundice. Newborn jaundice is very common during the first week of life because the baby's liver is not fully mature.
  • Your child is taking a medicine that raises the bilirubin level in your child’s blood.
  • Your child has an infection.
  • Your child has a liver or digestive system disease, such as hepatitis or a blocked bile duct.
  • Your child has a blood problem, such as anemia or a different blood type than his or her mother.
  • Your child has Gilbert's syndrome. Gilbert's syndrome is a harmless genetic condition that causes no symptoms other than mild jaundice.

If the bilirubin is low, your child many not need any more tests. If it’s high, your child may have a blood test to confirm the results. (The transcutaneous bilirubin measurement is easier and quicker to do than a blood test, but it’s not as accurate.)

What if the test result is not normal?

Test results are only one part of a larger picture that takes into account your child’s medical history, physical exam, and current health. Sometimes a test needs to be repeated to check the first result. Talk to your child’s healthcare provider about the test result and ask questions, such as:

  • If your child needs more tests
  • What kind of treatment your child might need
  • What lifestyle, diet, or other changes your child might need to make
Written by Robert M. Brayden, MD, Professor of Clinical Pediatrics, University of Colorado School of Medicine.
Pediatric Advisor 2018.1 published by Change Healthcare.
Last modified: 2016-04-19
Last reviewed: 2016-05-11
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
© 2018 Change Healthcare LLC and/or one of its subsidiaries
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