What is the term for jaundice that appears within the first 24 hours after birth?

Jaundice that appears within the first 24 hours after birth is classified as pathologic jaundice. This early onset indicates an underlying issue that requires further investigation, as it is typically not a normal physiological response.

Physiologic jaundice, which occurs later, usually manifests after the first 24 hours and is a common occurrence due to the immature liver's inability to process bilirubin efficiently. Neonatal jaundice is a broader term encompassing jaundice in newborns, but it does not specify the timing of its onset. Severe jaundice refers to particularly high levels of bilirubin but does not denote the timing or the underlying causes. Thus, the specificity of pathologic jaundice is critical for clinicians as it suggests the need for proper evaluation and management to prevent complications.