Jaundice in Babies

Dr.  Parang Mehta, MD.

About half of all babies will develop some jaundice.  It is common to see some yellowness in the eyeballs, and perhaps on the face, too.  Considering how common it is, is there a need to be concerned about jaundice in a baby?

What is Jaundice?

Jaundice is a yellow colour of the eyes and skin.  It is caused by the accumulation of a pigment called bilirubin in the baby's blood.  About one percent of the body's red blood cells are destroyed each day, in a normal human being.  The red blood cells contain hemoglobin, and bilirubin is derived by its metabolism.

Before birth, all the bilirubin produced by the baby is transferred across the placenta.  After birth, the baby's liver has to take up the job of removing bilirubin from the body.  It needs a while for this system to begin functioning, and some bilirubin accumulates.  This mild jaundice, which is quite a normal phenomenon, is called Physiological Jaundice of the Newborn.  It usually clears up by day 7-10.

Sometimes, this jaundice rises to high levels, and becomes dangerous.  It is then called exaggerated jaundice.  Deep jaundice can also be caused by either an increased production of bilirubin in the body, or a delay in the excretion by the liver (see sidebar).  

Common Causes of Deep Jaundice

How deep is deep?

Deep jaundice is associated with both immediate and long term risks.  Jaundice is measured by testing the blood for bilirubin levels.  This is the dangerous substance in jaundice.

Normal levels in adults and children are less than one milligram per decilitre of blood (written as mg/dl).  A decilitre is a tenth of a litre, or 100 millilitres.  However, babies always have a rise in bilirubin, which is a normal part of adaptation to life in the outside world.  Levels of up to 10 mg/dl don't worry a pediatrician at all, as long as the child is full term and healthy.

A serum bilirubin level of 15 mg/dl is worrisome, as bilirubin is believed to cause brain damage if the level reaches 20 mg/dl.  However, this is not a rigid figure.  Many healthy full term babies have levels of up 25 mg/dl, and have no residual effects.  On the other hand, babies with prematurity, sepsis, asphyxia, or other risk factors can suffer brain damage at bilirubin levels lower than 20 mg/dl also.

Dangers of Jaundice

It's not the yellow colour, it's the bilirubin that is dangerous.  When there are high levels of bilirubin in the blood, it penetrates into the brain and deposits there.  This can have long term effects on the child.  The deposition of bilirubin in the brain and the effects are known as Kernicterus.  Kernicterus can cause death of a baby, if left untreated.

A high blood level of bilirubin for even a few hours can be dangerous

Once bilirubin reaches the brain, it can cause several effects:

Bilirubin encephalopathy initially causes lethargy, limpness and poor sucking in the baby.  Later there is stiffness of the body, the back is arched, and fever and fits may occur.  The crying is very high-pitched.  If the child survives, the body is limp for several years, before a stage of stiffness appears.  These children have significant mental and developmental retardation, and often a type of cerebral palsy called choreoathetoid cerebral palsy.

Detecting Jaundice

Most often this is done visually.  Yellowness of the eyes (difficult to see in a newborn) or face, is the first sign of jaundice.  The presence of jaundice can be confirmed by a blood test.

The severity of jaundice can be roughly judged by it's extent on the baby's body.  If the jaundice is restricted to the face and chest only, the bilirubin levels are likely to be below 10 mg/dl.  Jaundice on the abdomes signifies deeper jaundice - blood levels are likely to be 12-15 mg/dl.  Jaundice on the thighs means even deeper jaundice, and jaundice on the soles of the feet are usually associated with bilirubin blood levels of 20 mg/dl or higher.  


Treatment of Newborn Jaundice

Last Revision: May 12, 2020