Neonatal jaundice is commonly observed among newborn infants, caused by hyperbilirubinemia. Severe hyperbilirubinemia should be recognized and treated to prevent kernicterus, a condition characterized by irreversible neurological damage. In most cases, hyperbilirubinemia results from a physiological increase in the unconjugated bilirubin concentration, combined with immature mechanisms for conjugation and enhanced enterohepatic circulation. However, certain conditions (e.g. prolonged jaundice, onset in the first 24 hours after birth, rapid rise in serum bilirubin, etc.) should raise the suspicion of an underlying pathologic mechanism. In general, unconjugated hyperbilirubinemia can be caused by (1) an increased, pathologic production of bilirubin, (2) a deficiency of hepatic uptake, (3) an impaired conjugation of bilirubin, (4) an increased enterohepatic circulation of bilirubin, or (5) a combination of the above . In case of pathologic unconjugated hyperbilirubinemia, an increased production of bilirubin due to hemolysis is the most likely cause. Therefore, a common approach in the diagnostic work-up of neonatal unconjugated hyperbilirubinemia is to differentiate between hemolytic and non-hemolytic diseases as a first step .