Hyperbilirubinemia and Jaundice

Hyperbilirubinemia is a condition in which there is too much bilirubin in your baby’s blood.

When red blood cells break down, a substance called bilirubin is formed. Babies are not easily able to get rid of the bilirubin, and it can build up in the blood and other tissues and fluids of your baby’s body. This is called hyperbilirubinemia. Because bilirubin has a pigment or coloring, it causes a yellowing of your baby’s skin and tissues. This is called jaundice.

Depending on the cause of the hyperbilirubinemia, jaundice may appear at birth or at any time afterward.

About 60 percent of term newborns and 80 percent of premature babies develop jaundice. Infants of diabetic mothers and of mothers with Rh disease are more likely to develop hyperbilirubinemia and jaundice.

Although low levels of bilirubin are not usually a concern, large amounts can circulate to tissues in the brain and may cause seizures and brain damage. This is a condition called kernicterus.

Symptoms may include:

• Yellow coloring of your baby’s skin (usually beginning on the face and moving down the body)
• Poor feeding or lethargy

During pregnancy, the placenta excretes bilirubin. When your baby is born, your baby’s liver must take over this function. There are several causes of hyperbilirubinemia and jaundice, including:

• Physiologic jaundice: Occurs as a “normal” response to your baby’s limited ability to excrete bilirubin in the first days of life
• Breast milk jaundice: About 2 percent of breastfed babies develop jaundice after the first week
• Breastfeeding jaundice: Occurs in some baby’s in the first week due to low intake or dehydration
• Jaundice from hemolysis: A condition that results from the breakdown of red blood cells due to hemolytic disease of the newborn (Rh disease), polycythemia, or hemorrhage
• Inadequate liver function: Due to infection or other factors

The timing of the appearance of jaundice helps with the diagnosis. Jaundice appearing in the first 24 hours is quite serious and usually requires immediate treatment. When jaundice appears on the second or third day, it is usually “physiologic.” However, it can be a more serious type of jaundice.

When jaundice appears on the third day to the first week, it may be due to an infection. Later appearance of jaundice, in the second week, is often related to issues with breast milk feedings, but may have other causes.

Diagnostic procedures for hyperbilirubinemia may include:

• Direct and indirect bilirubin levels: these reflect whether the bilirubin is bound with other substances by the liver so that it can be excreted (direct), or is circulating in the blood circulation (indirect)
• Red blood cell counts
• Blood type and testing for Rh incompatibility (Coomb’s test)

Treatment depends on many factors, including the cause of the hyperbilirubinemia and the level of bilirubin. The goal is to keep the level of bilirubin from increasing to dangerous levels. Treatment may include:

• Phototherapy: Since bilirubin absorbs light, jaundice and increased bilirubin levels usually decrease when your baby is exposed to special blue spectrum lights. Phototherapy may take several hours and it is used throughout the day and night. Your baby's position is changed to allow all of the skin to be exposed to the light. Your baby's eyes must be protected and the temperature monitored during phototherapy. We check your baby's blood levels to monitor if the phototherapy is working.
• Fiberoptic blanket: Another form of phototherapy is a fiberoptic blanket placed under your baby. This may be used alone or in combination with regular phototherapy.
• Exchange transfusion: to replace your baby's damaged blood with fresh blood. Exchange transfusion helps increase the red blood cell count and lower the levels of bilirubin. An exchange transfusion is done by alternating giving and withdrawing blood in small amounts through a vein or artery. Exchange transfusions may need to be repeated if the bilirubin levels remain high.
• Ceasing breastfeeding for one or two days: Treatment of breast milk jaundice often requires stopping the breastfeeding for one to two days, and giving your baby formula often helps lower the bilirubin levels.
• We treat any underlying cause of hyperbilirubinemia, such as infection.

Children and adolescents with all forms of non-malignant blood disorders, including anemias, bleeding problems, blood clots, platelet disorders, and red and white blood cell disorders, are treated through our Blood Disorders Center. If necessary, Boston Children’s also offers access to the largest pediatric stem cell transplantation program in New England.