How Long Does It Take Jaundice to Turn into Kernicterus?


While jaundice is a common condition for newborn infants, it is important for doctors to promptly identify and treat it. Untreated jaundice in infants can progress into kernicterus, a rare but serious condition that results in brain damage. Kernicterus can result when excess levels of bilirubin build up in the brain because of untreated jaundice. When the levels are too high, bilirubin can become toxic and cause hyperbilirubinemia. Excessive bilirubin from jaundice can accumulate in the body and cause damage to the central nervous system, including the brain. Here’s some information about jaundice in newborns and how rapidly it might develop into kernicterus from the birth injury attorneys at Raynes & Lawn.

What Is Jaundice in Infants?

Newborn jaundice is a yellowing of the baby’s eyes and skin. This results because of the buildup of excess bilirubin in the bloodstream of the infant. Bilirubin is a yellow pigment of red blood cells that is released when the cells are broken down in the liver. If the liver doesn’t adequately process bilirubin, it can build up in the blood and cause a yellow appearance.

In most cases, infant jaundice is short-lived and will quickly go away with exposure to sunlight. However, some infants develop jaundice that doesn’t go away very easily. When that happens, it can be serious and require prompt management and treatment. If an infant’s jaundice becomes severe and is left untreated or is improperly managed, the excess levels of bilirubin in the baby’s blood can cause kernicterus and permanent brain damage.

Prevalence of Jaundice in Infants

Infants are susceptible to jaundice because the liver doesn’t finish developing until up to two years following birth. An infant’s liver can easily become overworked, leading to increased bilirubin levels and jaundice.

Infant jaundice is very common and affects up to 60% of newborns. Among infants who are born before 36 weeks of gestation, jaundice affects an average of 80%.

What Is Kernicterus?

Kernicterus is a rare neurological condition caused by an excess buildup of bilirubin in the bloodstream. This yellowish pigment is a byproduct in the blood of hemolysis, which is the breakdown of hemoglobin contained in the red blood cells. During pregnancy, the mother’s liver breaks down bilirubin for the developing fetus. However, after birth, infants must break bilirubin down on their own. When an infant’s liver can’t efficiently break down bilirubin, the baby can develop jaundice. Infants with severe jaundice that is not properly treated can develop kernicterus caused by toxic levels of bilirubin in the brain. Kernicterus can cause damage to the brain and central nervous system and lead to multiple symptoms and complications.

Causes of Kernicterus

Kernicterus can result when an infant’s severe jaundice is not properly treated. When this occurs, bilirubin can accumulate to toxic levels and damage the infant’s brain cells. The primary cause of jaundice is hyperbilirubinemia, which is excess bilirubin that is released into the blood when old red blood cells are broken down.

Infants produce red blood cells faster and break them down more quickly than adults during the first few days following birth, which means they also produce more bilirubin. In adults with fully developed livers, the liver filters bilirubin out and releases it into the intestines. Since a newborn’s liver is immature, it might not be able to filter out bilirubin from the blood fast enough, so bilirubin levels build up in the blood. Jaundice that occurs because of this process is referred to as physiologic jaundice, and it typically occurs during the second or third day following the infant’s birth.

Jaundice in newborns can also be caused by an underlying condition and might appear either earlier or later than physiologic jaundice. The following underlying conditions can cause infant jaundice:

  • Sepsis caused by an infection in the baby’s blood
  • Internal bleeding
  • Blood type incompatibility between the mother and infant
  • Other bacterial or viral infections
  • Malfunction of the liver
  • Enzyme deficiency
  • Abnormal red blood cells in the baby that causes the blood cells to break down more rapidly
  • Scarred or blocked bile ducts in the baby (biliary atresia)

Risk Factors for Jaundice and Potential Kernicterus

There are several risk factors for infant jaundice, including risk factors for severe jaundice that can result in kernicterus. The major risk factors are detailed below.

Preterm Birth

Preterm infants who are born before 38 weeks might have livers that can’t process bilirubin as quickly as full-term babies. Premature infants also might not feed as frequently and have fewer bowel movements. This means that they might eliminate less bilirubin through stools. These factors can lead to excess levels of bilirubin building up in the blood of premature infants, resulting in jaundice. If it is not properly treated, severe jaundice in premature babies can lead to kernicterus.

Bruising During Labor and Delivery

A newborn can suffer significant bruising during a difficult labor and delivery process. When an infant has extensive bruising, jaundice can be caused because of the need to break down more red blood cells from the bruised areas than would otherwise be necessary.

Incompatible Blood Types

When the infant has a different blood type than the mother, antibodies might have been passed from the mother to the infant through the placenta, The presence of these incompatible blood antibodies causes the baby’s liver to break down red blood cells at an abnormally rapid rate. This rapid breakdown of red blood cells might be too much for the infant’s liver to handle, leading to jaundice and potential kernicterus if not properly treated.


Babies who breastfeed have a higher risk of developing jaundice. This is especially true for infants who have trouble nursing or obtaining sufficient nutrition through breastfeeding. Not getting enough calories or fluids through breastfeeding can lead to jaundice. However, breastfeeding is still recommended because of its benefits. If your infant has trouble with breastfeeding, talk to your doctor to ensure your infant is getting sufficient fluids and nutrition through supplementation.


Infants with East Asian ancestry have a higher risk of developing jaundice than infants of other races.

Complications of Excess Bilirubin Levels

If not properly treated, severe jaundice and the excess levels of bilirubin involved can cause serious complications.

Acute Bilirubin Encephalopathy

Bilirubin is toxic to brain cells. When an infant is severely jaundiced, bilirubin might pass into the brain and cause a condition called acute bilirubin encephalopathy. Widespread, lasting damage can be prevented with prompt treatment.

The following signs might indicate that an infant with jaundice has acute bilirubin encephalopathy:

  • Fever
  • Trouble waking
  • Listlessness
  • Arching of the body and neck backward
  • Poor feeding or suckling
  • High-pitched crying


Kernicterus can result when acute bilirubin encephalopathy causes permanent brain damage. If a baby develops kernicterus, they can suffer from the following potential complications:

  • Athetoid cerebral palsy
  • Hearing loss
  • Improper development of the enamel of the teeth
  • Eyes permanently fixed in an upward gaze

Symptoms of Kernicterus

Kernicterus is progressive and worsens as damage to the brain spreads. The symptoms of kernicterus differ based on the stage of kernicterus’s progression.

Stage One Kernicterus Symptoms

The symptoms of stage one kernicterus include the following:

  • Severe, prolonged infant jaundice that doesn’t go away without treatment
  • Significant difficulty with latching on, suckling, and feeding with both breastfeeding and bottle feeding
  • Floppiness or a severe lack of muscle tone (hypotonia)
  • Abnormal lethargy/chronic fatigue

Stage Two Kernicterus Symptoms

The following are symptoms of stage two kernicterus:

  • Uncontrolled, sudden seizures caused by spreading neurologic damage
  • Bulge in the fontanel of the skull

Stage Three Kernicterus Symptoms

The following are symptoms of stage three kernicterus:

  • Seizures that increase in intensity and frequency
  • Substantial hearing loss and the inability to hear sounds at high frequencies
  • Trouble with muscle control and movement
  • Extensive muscular rigidity

How Kernicterus Occurs

As previously explained, kernicterus results when jaundice is improperly managed. This can lead to blood bilirubin levels becoming so excessive that brain damage results. The body continuously manufactures bilirubin through hemolysis during the breakdown and disposal of old red blood cells. When the cells are broken down, most of their byproducts are used in other areas of the body. However, the body does not have any use for bilirubin, so it is discarded.

Unconjugated bilirubin is the form of bilirubin that exists when it is initially created during the breakdown of red blood cells. This form is toxic because it is insoluble and can build up in the tissues of the body. The liver filters out unconjugated bilirubin and converts it into the conjugated form, which is soluble. Conjugated bilirubin is then excreted into the intestines and can be removed from the body through stools or urine.

Many newborn infants have livers that are incapable of efficiently filtering and converting unconjugated bilirubin quickly enough to keep up with the body’s production of bilirubin. This can result in a buildup of unconjugated bilirubin and lead to jaundice. In most cases, jaundice in newborns is temporary. The liver is often able to quickly catch up with the conversion of unconjugated bilirubin. However, the livers of some infants are unable to catch up with the backlog of unconjugated bilirubin, resulting in jaundice that becomes progressively severe. If it is not properly treated, severe jaundice can result in kernicterus when the unconjugated bilirubin enters the brain and causes damage to the cells and tissues.

Diagnosis of Kernicterus

Doctors typically diagnose kernicterus presumptively. It is nearly impossible to definitively diagnose kernicterus short of an autopsy. Doctors who suspect kernicterus will complete physical examinations of the infants to check for signs of jaundice. They might order blood tests and use light meters to check the bilirubin levels and see whether they are excessive enough to indicate possible kernicterus.

Treatment Options for Kernicterus

Once kernicterus develops, the damage can’t be reversed. The treatment options for kernicterus instead focus on preventing further jaundice and damage.

During treatment, the medical professionals will focus on decreasing the levels of unconjugated blood bilirubin. Infants must receive early treatment to prevent the damage from worsening.

Exchange Transfusions

The infant might undergo exchange transfusions through which the blood is repeatedly withdrawn and replaced with donor blood until most of it has been exchanged.


Infants might also undergo plasmapheresis. During this procedure, unwanted substances are removed from the blood by removing the blood and separating the blood cells from the plasma. The plasma will then be replaced with donor plasma before the blood is transfused into the infant.


Phototherapy or light therapy will likely be used to manage the infant’s jaundice. Medical professionals will focus intense fluorescent lights on the infant’s bare skin while shielding their eyes. Phototherapy speeds up the baby’s excretion of bilirubin and the process of decomposing it.

Liver Transplant

The application of light therapy becomes less effective as the baby ages and the skin thickens. Because of this, a liver transplant might be recommended. A liver transplant might be recommended early in the baby’s life to try to prevent further brain damage associated with kernicterus.

Fortunately, infant jaundice can be effectively treated using light therapy. If newborn jaundice is promptly identified and properly managed and treated, kernicterus might be prevented.

Is There a Cure for Kernicterus?

There is no cure for kernicterus. Once the brain is damaged because of the buildup of excessive levels of bilirubin in the brain, the damage cannot be reversed. Brain cells do not regenerate.

How Long Does it Take Kernicterus to Develop?

An infant with severe jaundice who does not receive proper treatment can develop kernicterus in as little as two to five days following birth. However, kernicterus is rare, and infants with jaundice typically do not develop this condition.

Kernicterus and Medical Malpractice

Doctors, nurses, and other medical professionals are expected to properly monitor infants following birth to check for signs of jaundice. When medical providers fail to identify infant jaundice and properly treat it, kernicterus might develop. In this situation, the medical provider’s substandard care might rise to the level of medical malpractice.

To file a lawsuit for medical malpractice in Pennsylvania, you must file a certificate that a medical expert has reviewed the medical records and believes that the doctor’s care fell below the expected standard and caused your baby’s condition. A child injury lawyer at Raynes & Lawn can work with a medical expert to determine the relevant standard of care and determine whether you have a viable malpractice claim.

Damages in a Kernicterus Claim

Damages in a kernicterus claim are monetary amounts designed to cover the losses your family and baby have suffered as a result of the provider’s medical negligence. The following are some of the types of damages that might be recoverable in a kernicterus lawsuit:

  • Past and future medical expenses
  • Ongoing therapy costs to treat complications
  • Home modification for children who develop athetoid cerebral palsy caused by kernicterus
  • Pain and suffering
  • Emotional distress
  • Disability
  • Other damages

The complications of kernicterus can require lifelong care and can be very expensive. By filing a medical malpractice lawsuit, you might recover enough compensation to provide your child with all of the care they will need throughout their life.

Contact a Birth Trauma Attorney

If your child has been diagnosed with kernicterus, you should speak to an experienced attorney at Raynes & Lawn. We can review the medical records and help you understand whether the treatment your child received amounted to medical negligence. Our attorneys have fought for malpractice victims for more than five decades and have recovered billions of dollars on their behalf. Call us today for a free consultation at 1-800-535-1797.


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