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My newborn baby is jaundiced. What does this mean and what should I do? 

Jaundice in babies is very common and risk of brain damage from too much jaundice is very uncommon. We explain newborn jaundice, hyperbilirubinemia and kernicterus so parents and families can better know if their baby is at risk  and what to do to prevent brain damage.

When signs of acute bilirubin encephalopathy (ABE), also known as acute kernicterus, occur in a jaundiced baby, brain damage is starting to occur. Immediate treatment should be started to prevent further damage or the damage may become permanent.

If you are worried that this is occurring right now in your baby, click here to skip down to the section below with the same name as above.

JAUNDICE in newborns and its treatment

Most newborn infants are jaundiced in the first week or two of life because babies produce more bilirubin after they are born, and their mechanism for eliminating bilirubin (an enzyme) takes a few days to mature. In a normal term baby bilirubin and jaundice is highest 3-5 days after birth, and then subsides for the rest for the rest of their lives. Note that a little bit of jaundice due to bilirubin is good for babies since bilirubin is a natural anti-oxidant but, of course, too much of a good thing can be harmful. 

To put things into perspective, in the USA, there are about 4 million babies born each year. If 60% of normal, healthy term babies are jaundiced then 2.4 million babies per year are jaundiced. Estimates of the number of babies with kernicterus is between about 1 in 40,000 and 1 in 110,000 live births. This data is not from the USA but from similar high-income countries such as Canada (1 in 40,000 or 44,000), the United Kingdom and Denmark. The incidence of kernicterus in low and middle-income countries is much higher.

Most healthy term newborns are not affected at all if the bilirubin is less than 20 mg/dL (342 µM international units) of kernicterus. In the USA the number of babies with bilirubin levels reaching a level of 25 mg/dL, called severe or extreme hyperbilirubinemia, is 1 in 1,000 babies. So, although kernicterus is rare, it is a DISASTER for those rare individuals, perhaps 100 per year in the USA if we use Canada’s data, who have severe classical or dystonic-predominant kernicterus, with abnormal muscle tone and severe abnormality or lack of voluntary movements in an individual whose cognitive function is, by the way, unaffected and intact. 

Although many babies look jaundiced, they are not deeply jaundiced, not jaundiced below their abdomen, and they act normal – they nurse, they are not too sleepy, they have normal muscle tone, their cry is normal, and they don't arch their backs. Jaundice can sometimes be seen in the sclera, the "whites'' of the eyes, which look yellow. Most neonatal jaundice is not harmful, but when it progresses to affect the brain and starts to cause kernicterus, it is a medical emergency.

Yellow coloring of the skin in jaundiced babies usually starts at the top, their head, and progresses down the body toward the toes. As the bilirubin goes higher, the bilirubin can no longer be held inside the blood vessels and outside of the brain.  Then, jaundiced babies may show signs and symptoms of distress caused by bilirubin getting into the brain, known as acute bilirubin encephalopathy (ABE) also called acute kernicterus.


​As more bilirubin continues to move into the brain, there is a progression of signs and symptoms. Initially they may be unusually sleepy and difficult to arouse (also called lethargic), not nurse as frequently, and develop abnormal low muscle tone becoming hypotonic (floppy) with episodes of increased (hypertonic) muscle tone, a high pitched cry, and arching of the back into a very contorted position known as opisthotonus or retrocollis. As ABE progresses fever, and they may even develop seizures (convulsions). The baby may go on to develop fever and even develop seizures (convulsions). ABE is an emergency and the baby should be seen for treatment as soon as possible - see The Jaundiced Baby with Signs of Acute Bilirubin Encephalopathy (ABE) or Acute Kernicterus:  A Medical Emergency – below

Information for Parents: Newborn Jaundice and its Treatment

Excessive jaundice in newborn infants may cause brain damage. Jaundice is caused by a high level of bilirubin in the blood (hyperbilirubinemia) and tissues. Bilirubin is a product of the breakdown of red blood cells, and it can accumulate in the blood for a variety of reasons. It is taken to the liver which puts uses an enzyme (UGT1A1) to attach glucuronide (a sugar compound) making it non-toxic and able to be exceeded into the gut and out the stool. Factors, such as prematurity, Rh and ABO blood group incompatibilities between infant and mother, problems with red blood cell membranes in babies with G6PD deficiency, hereditary spherocytosis or elliptocytosis, the genetic disorder of Gilbert’s syndrome (which often runs in families and cause very slight jaundice and hyperbilirubinemia), and excessive bruising, especially bleeding under the skin of the scalp (cephalohematomas and caputs), can increase bilirubin production and lead to excessive jaundice and hyperbilirubinemia. The red blood cell membrane disorders such as G6PD, hereditary spherocytosis or elliptocytosis are heriditary though families might not be aware they have it. Rh disease occurs with Rh negative blood type mother have been sensitized against Rh positive blood in previous preganancies and make an antibody against baby's blood cells that can cause extremely severe hyperbiliruibinemia if not prevented and treated, and Gilbert's syndrome that is a very common often unrecognized condition that causes very mild lifelong hyperbilirubinemia which has some health benefits but may occasionally in newborns in combination with other causes of hyperbilirbuinemia cause the bilirubin to go temporarily too high.


Most babies with high bilirubin levels can be effectively treated with phototherapy (treatment with visible blue, blue-green or white light- not ultraviolet [not UV] light). Bilirubin is especially sensitive to blue light.


Blue (or blue-green) light causes bilirubin to change from a toxic form to a non-toxic form that is water-soluble that can be eliminated by the kidneys. At higher, more dangerous levels of bilirubin, or in certain situations where the bilirubin is rising or expected to rise very rapidly, a more extreme treatment may be used, such as a double volume blood exchange transfusion to rapidly remove toxic bilirubin from the blood. Small amounts of blood are removed and replaced repeatedly until most of the babies blood is replaced. This is usually done with blood equal to 8-10% of the baby's body weight.


Sunlight may also help lower bilirubin levels like the phototherapy lights, BUT putting the baby in the sunlight is not recommended as a treatment for hyperbilirubinemia because the amount of sunlight needed to effectively lower the bilirubin would be too much and cause sunburn.

The Jaundiced Baby with Signs of Acute Bilirubin Encephalopathy (ABE) or Acute Kernicterus:  A Medical Emergency

When signs of acute bilirubin encephalopathy (ABE), also known as acute kernicterus, occur in a jaundiced baby, brain damage is starting to occur. Immediate treatment should be started to prevent further damage or the damage may become permanent.

Treatment should consist of immediate, high-intensity triple-bank phototherapy lights put as close as possible to the baby and hydration with fluids. A measurement of blood bilirubin should be sent STAT, but phototherapy should be started before the bilirubin results come back. The baby should be hydrated with fluids and if the baby is not too sick should be given an elemental infant formula by mouth or with a feeding tube from the nose or mouth into the stomach. The baby should be blood typed for a possible double volume blood exchange transfusion, which should be done unless there is a large drop in the bilirubin and the baby improves before the blood is ready for an exchange transfusion.



Bring your baby immediately to an Emergency Department. Call your baby's doctor. Insist on a Stat (immediate, emergency) Bilirubin level. If the baby is severely jaundiced and symptommatic with signs of ABE, ask them to start immediate treatment - IV fluids and fluids by mouth if baby is not too lethargic (preferably with elemental formula which is known to remove bilirubin via the stool), and start intensive phototherapy. DON'T wait for the result and especially if the healthcare providers don't believe the result and want to repeat it, don't stop the treatment or valuable time will be lost. The treatment is not harmful. If they want to make sure  there is not something else going on, maybe an infection or meningitis, that important and okay, but no reason to stop treating for ABE and lowering the bilirubin until the test results are known. 


See above.

If the baby is severely jaundiced and symptomatic with signs of ABE, start immediate treatment. If the index of suspicion is high - the baby is very jaundiced with signs of ABE - then begin treatment immediately for dehydration with IV fluids (to help lower bilirubin acutely). If able to feed, give PO elemental formula by bottle or naso-gastric tube (helps remove bilirubin via the gut and prevent enterohepatic circulation) and begin high-intensity phototherapy. These can be done as much as possible in combination with evaluations for other causes, e.g. septic workkup ± lumbar puncture for meningitis. Note that with sepsis or acidosis, total or conjugated bilirubin levels may cause neurotoxicity at signficantly lower levels. Also, not that in neonates, the consensus is to use total bilirubin, not unconjugated a.k.a indirect bilirubin, to assess need for treatment. Note also that some babies with extreme hyperbilirubinemia, i.e., levels of ~40 mg/dL, may tolerate this temporarily with no neurological symptoms or signs for a few hours, and then suddenly decompensate with ABE. 

Acute Bilirubin Encephalopathy (ABE)

This means that more bilirubin has entered the brain than the baby’s brain can handle, and it starts to cause abnormal brain function. These signs of ABE may be subtle and mild at first, progressing to become more severe from #1 to #5 below:

  1. Difficulty nursing, being unusually sleepy and difficult to arouse (also called lethargic),

  2. Abnormal muscle low tone (called floppy or hypotonic) with episodes of high muscle tone (hypertonic),

  3. A high pitched cry 

  4. Arching of the back into a contorted position known as opisthotonus or retrocollis

  5. Setting sun sign – the eyes look down and one can see the "white" of their eyes under the eyelids above the pupils

These often occur in a progression from mild to severe, from lethargic to abnormal tone, a high-pitched cry, and arching of the back as the effect on bilirubin on the brain progresses. Finally, in the most severe cases babies with ABE may progress to develop fever and even seizures (convulsions) and heart, blood pressure and breathing problems.

Some physicians have asked me, “when the signs occur, isn't it too late to treat?” No! 


Although damage may have already occurred, when the infant is jaundiced and signs of ABE are occurring, damage is continuing to occur. The sooner the bilirubin level in the blood is reduced, the better, and the less permanent brain damage will occur. This is a true emergency. Delay will make the damage worse.


With an excessively high bilirubin level, and with signs of acute kernicterus, arrangements should immediately be made for a double volume exchange transfusion. This may take a few hours, even in the best of medical centers. In the meantime, the baby should be given double or triple phototherapy with the lights as close as possible to the baby with maximal surface area exposed (and the eyes covered), and if the baby is not too sick the baby should be fed orally or by gavage tube with an elemental formula to eliminate bilirubin via the gut. Dehydration may be corrected by intravenous infusion, but gastrointestinal feeding should not be ignored unless the baby is comatose, having seizures or severely ill.

Preventing Brain damage

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