Unconjugated hyperbilirubinemia

Physiologic hyperbilirubinemia (most common cause)

Breastfeeding and breastmilk jaundice

Increased production of bilirubin: hemolysis (immune or nonimmune), sequestered blood (subdural hematoma, cephalhematoma, hemangioma, ecchymosis), polycythemia, sepsis

Decreased hepatic uptake or conjugation: hypothyroidism, Gilbert syndrome, Crigler-Najjar syndrome (types I and II), transient familial neonatal hyperbilirubinemia (Lucey-Driscoll syndrome)

Conjugated hyperbilirubinemia

Hepatobiliary disorders: neonatal idiopathic hepatitis, infections (TORCH, echovirus, syphilis, systemic infections), prolonged parenteral nutrition, severe hemolytic disease, metabolic disorders (galactosemia, glycogen storage diseases)

Ductal disturbances in bilirubin excretion: biliary atresia, choledochal cyst, bile plug syndrome