Etiological analyses of marked neonatal hyperbilirubinemia in a single institution in Taiwan.

BACKGROUND Hyperbilirubinemia is a common disorder during the neonatal period. Severe neonatal hyperbilirubinemia (NH) carries a potential for permanent neurological impairment. The current study analyzed possible etiologies leading to NH. METHODS A retrospective cohort of neonates with total serum bilirubin (TSB) ≥ 20 mg/dL was surveyed from 1995 to 2007. Subjects with gestational ages < 34 weeks were excluded, leaving a total of 413 enrolled neonates. RESULTS The most common etiology in relation to marked NH was breast milk feeding (38.5%), followed by glucose-6-phospahate dehydrogenase (G6PD) deficiency (24.0%), ABO incompatibility (21.8%), extravascular hemorrhage (6.5%), Rh incompatibility (2.9%), bacterial infection (2.2%), hereditary spherocytosis (1.2%), dehydration (1.2%), diabetic mother (1.0%), polycythemia (0.7%), and gastrointestinal obstruction (0.7%). Other rare etiologies included Down syndrome, Chinese herb intake, asphyxia, galactosemia and congenital hypothyroidism. We did not identify any known cause in 63 neonates (15.3%). Neonates with more than one etiology tended to have higher TSB than subjects without a known etiology (p < 0.05). Anemia was more common in those with G6PD deficiency, blood group incompatibility, hereditary spherocytosis, and gastrointestinal obstruction. Neonates fed breast milk tended to have prolonged NH. CONCLUSION This study depicts the clinical features of marked NH. Breast milk feeding, G6PD deficiency and ABO incompatibility are common etiologies in Taiwan. Prolonged NH is more common in neonates fed breast milk than those who were given formula.