Final answer:
Kernicterus is the accumulation of bilirubin in brain tissue, which can cause neurological damage, especially in newborns due to their immature blood-brain barrier.
Step-by-step explanation:
Kernicterus is an abnormal accumulation of bilirubin in b. Brain tissue.Bilirubin is a yellow bile pigment produced as a byproduct of the breakdown of old red blood cells. Normally, the liver processes bilirubin, making it soluble in water to be excreted in bile. However, in certain conditions like hyperbilirubinemia (high levels of bilirubin), jaundice or icterus may occur, giving tissues a yellow coloration. Newborns are particularly vulnerable as they sometimes lack sufficient UDP glucuronyl transferase activity to conjugate the bilirubin for proper excretion. When levels exceed 25 mg/100 ml, kernicterus can develop because bilirubin deposits in the brain tissue due to the immature blood-brain barrier, potentially causing neurological damage.
Diseases such as Crigler-Najjar syndrome, which involves missing liver enzyme activity, and Gilbert's disease, which features lowered enzyme activity, can lead to increased bilirubin levels. Excessive red cell breakdown (haemolytic jaundice) and liver disorders can also result in elevated bilirubin and jaundice.