Name a common cause of neonatal jaundice in the first 24 hours that is typically not severe.

Name a common cause of neonatal jaundice in the first 24 hours that is typically not severe.

• A. ABO incompatibility
• B. Cephalohematoma from birth trauma causing mild early jaundice
• C. Physiologic jaundice
• D. Breastfeeding jaundice

Answer: (B)

Within the first day, jaundice usually arises from increased breakdown of fetal red blood cells or limited liver clearance. A cephalohematoma from birth trauma fits best because the birth-related bleed increases red blood cell turnover, raising unconjugated bilirubin quickly. However, since the amount of bilirubin generated is modest and the liver is just starting to conjugate, the jaundice tends to be mild and resolves as the hematoma heals. Other causes in the choices either tend to appear later or are more likely to cause more pronounced jaundice: ABO incompatibility can produce significant jaundice from hemolysis and may require closer monitoring; physiologic jaundice typically appears after 24 hours and peaks around a few days; breastfeeding jaundice emerges after the first day or two due to caloric intake effects.

Within the first day, jaundice usually arises from increased breakdown of fetal red blood cells or limited liver clearance. A cephalohematoma from birth trauma fits best because the birth-related bleed increases red blood cell turnover, raising unconjugated bilirubin quickly. However, since the amount of bilirubin generated is modest and the liver is just starting to conjugate, the jaundice tends to be mild and resolves as the hematoma heals.

Other causes in the choices either tend to appear later or are more likely to cause more pronounced jaundice: ABO incompatibility can produce significant jaundice from hemolysis and may require closer monitoring; physiologic jaundice typically appears after 24 hours and peaks around a few days; breastfeeding jaundice emerges after the first day or two due to caloric intake effects.