Neonatal Jaundice

A 5-day-old female neonate, born to an O-positive, antibody screen-negative mother, presents with jaundice. The infant is exclusively breastfed with good latch and feeds 10–12 times daily. Weight is 3.4 kg (birth weight 3.5 kg). Stool output is 4–5 stools per day, and urine output is normal. Direct antiglobulin test (DAT) is negative. Total serum bilirubin is 16 mg/dL, conjugated bilirubin 0.3 mg/dL. What is the most appropriate next step in management?

A 3-day-old male neonate, born to an O-positive mother, presents with jaundice. The infant is exclusively breastfed and has passed meconium twice. Antenatal serology showed the mother is O-positive, antibody screen negative. Postnatal direct antiglobulin test (DAT) is negative. Total serum bilirubin is 18 mg/dL, conjugated bilirubin 0.4 mg/dL. The infant's weight is 3.2 kg (birth weight 3.5 kg). What is the most likely diagnosis?

Which of the following is the primary mechanism of unconjugated hyperbilirubinemia in physiological jaundice of the newborn?

A 48-hour-old preterm neonate (34 weeks gestation) with ABO incompatibility (mother O, baby B) presents with a serum bilirubin of 16 mg/dL and rising rapidly. Phototherapy is being initiated. Which medication should be administered concurrently to reduce hemolysis and prevent further bilirubin rise?

A 3-day-old term neonate born to an O-positive mother presents with clinical jaundice. The mother is O-negative and unsensitized (indirect Coombs test negative at delivery). The infant's total serum bilirubin is 14 mg/dL. Which investigation is most appropriate to confirm hemolytic disease and guide management?