At what level does bilirubin cause brain damage in newborns?

 

What is Bilirubin Level for Brain Damage in newborns 

There is no specific bilirubin threshold at which brains of all the newborns would definitely be damaged causing guaranteed Kernicterus because risks of brain damage of newborns due to high bilirubin level depends whether the newborns are premature or full term. Besides, many other factors like baby’s gestational age, overall health, clinical symptoms, underlying health conditions can also impact on the risk of causing brain damage to newborns. 

 

Premature Newborns Level of Bilirubin causing Risks of Brain damage 

Premature babies may be at higher risks of brain damage even at bilirubin level of 20 mg/dL (unconjugated bilirubin)  due to many other conditions associated with prematurely Actually, process of bilirubin is handled by livers and premature babies’ livers are immature being not developed fully hence they are not able to efficiently process the bilirubin and excrete them out from body, causing bilirubin level increased in the body.

But I again say this is not a fixed threshold or rule that brain of every premature baby will be damaged as the baby reaches 20mg/dL of bilirubin level, many other factors detailed above are also associated with brain damage in newborn premature babies.  

 

Full term Healthy Newborns Level of Bilirubin causing Risks of Brain damage 

In full-term healthily babies whose livers are relatively mature than preterm babies, therefore the bilirubin level of 20 mg/dL (unconjugated) in their blood does not usually cause brain damage.

 

However, in such full term healthy babies, if 25 mg/dL of bilirubin level is found in their blood, still it is not guarantee that it will definitely cause brain damage to such healthily full term babies because there is no fixed threshold of brain damage due to increased bilirubin level.

 

However, 25 mg/dL bilirubin level is considered to be high even in full term healthily newborns and same should not be ignored in any way therefore proper monitoring and its treatment should be done accordingly.  

 

How does high bilirubin cause damage to brain of newborns? 

Bilirubin level can be measured in different forms like (1) total bilirubin (2) Conjugated bilirubin (3) Unconjugated bilirubin.

 

It is the unconjugated (Indirect) bilirubin, which if increased in blood stream, crosses the blood brain barrier and accumulates in brain tissues, hence causing damage to it.