Final answer:
Unconjugated hyperbilirubinemia occurs when a newborn's liver enzyme UDP glucuronyl transferase is underdeveloped, leading to an accumulation of bilirubin and the risk of kernicterus. Phototherapy or light therapy is a common treatment for high bilirubin levels.
Step-by-step explanation:
Indirect bilirubin is a form of bilirubin that cannot cross the blood-brain barrier (BBB) and therefore cannot deposit in basal ganglia and brainstem nuclei to cause kernicterus. Kernicterus is a condition of brain damage caused by high levels of bilirubin in the blood, especially if bilirubin is greater than 20.
Your question is incomplete. The meaning of your question is:
Indirect bilirubin cannot cross the BBB, deposit in basal ganglia and brainstem nuclei, and cause kernicterus (especially if bilirubin is >20).
So, what is the appropriate treatment if high bilirubin levels?