What characterizes kernicterus?

Kernicterus is primarily characterized by brain damage caused by elevated levels of bilirubin in the blood. This condition typically arises in newborns when jaundice, which results from an excess of bilirubin, becomes severe enough that bilirubin crosses the blood-brain barrier and damages neural tissues. The brain damage that occurs can lead to a range of serious neurological issues, including movement disorders, hearing loss, and cognitive impairments.

The other options, while they may describe symptoms or features associated with jaundice, do not specifically encapsulate the critical nature of kernicterus as it pertains to direct brain injury. Jaundice alone, while a significant sign of elevated bilirubin levels, does not encompass the broader implications and consequences such as permanent brain damage that kernicterus indicates. Symptoms like irritability, insomnia, fatigue, and malaise can be related to various conditions but do not uniquely define kernicterus. The defining aspect of kernicterus is the damage that occurs to the brain due to high bilirubin levels, highlighting the importance of monitoring and managing jaundice in newborns to prevent this serious complication.