Final answer:
The accumulation of bilirubin in an infant's blood due to ineffective removal by the liver results in a condition called jaundice. Newborns are especially vulnerable to the effects of high bilirubin levels, which can lead to brain damage. Treatment often includes phototherapy, which utilizes UV light to help breakdown bilirubin in the bloodstream.
Step-by-step explanation:
The build-up of bilirubin in an infant's blood can occur if the liver does not remove the chemical effectively. This condition is known as jaundice or icterus, where excessive bilirubin causes the skin and mucous membranes to take on a yellowish tint. Bilirubin is a waste product that results from the normal breakdown of red blood cells. The liver usually processes and excretes bilirubin in bile, which then enters the gastrointestinal tract and exits the body in the stool. However, conditions such as Crigler-Najjar syndrome, due to an absence of UDP glucuronyl transferase activity, can prevent the liver from converting bilirubin into its excretable form, leading to hyperbilirubinemia. In newborns, the situation is more delicate as their blood-brain barrier is not fully developed, making them susceptible to kernicterus, a condition where high levels of unconjugated bilirubin can lead to brain damage. To manage hyperbilirubinemia, newborns may be treated with phototherapy, as UV light helps break down bilirubin more quickly.