Serum gamma-glutamyl transpeptidase activity and bile acids in normal Taiwanese infants

To facilitate making a diagnosis of cholestatic liver disease in Taiwan, we have established reference ranges for serum gamma-glutamyl transpeptidase (gamma-GT) activity and bile acids in normal Taiwanese infants. The serum level of gamma-GT activity was assayed in 90 normal Taiwanese infants and children aged between 2 days and 2 years old. These data were analyzed in twenty-three 0-3-month-old, twenty-four 4-6-month-old, and forty-three 7-24-month-old infants. The mean values of serum gamma-GT activity were 47.4 +/- 26.6, 21.5 +/- 7.3, and 14.0 +/- 3.2 IU/L for the respective age groups. The highest reference gamma-GT values were 99.5, 35.8, and 20.3 IU/L for the respective age groups. The mean values of serum gamma-GT activity were highest in infants younger than 3 months, and these gradually decreased to the adult level with age (p < 0.01). Serum bile acids were measured in 24 premature and 56 full-term infants. The mean values of serum bile acids were 34.5 +/- 34.5 mumol/L in preterm infants and 18.7 +/- 21.9 mumol/L in full-term babies. The bile acid levels of preterm infants were higher than those in full-term babies (p < 0.01).