title: Determination of reference range of gamma glutamyl transferase in the neonatal intensive care unit.
abstract: OBJECTIVE
  We aimed to establish the reference range of gamma glutamyl transferase (GGT) in the first week of life at each gestational age (GA).
  
  
  METHODS
  This retrospective study included infants born and admitted before 7 days of age with no apparent congenital liver disease during four consecutive years. Early GGT levels measured at 3-7 days of age were analyzed according to GA. Differences according to sex, mode of delivery, small for gestational age, and the predictability for cholestasis were analyzed.
  
  
  RESULTS
  We analyzed early GGT values in 2091 neonates. The average reference value in neonates (156.7 ± 98.2 IU/L) was much higher than that in adults. The GGT values were significantly higher in preterm than in term infants and in male infants than in female infants. Mode of delivery and small for gestational age were not significantly related to GGT level. Early GGT had no predictive value for cholestasis occurrence.
  
  
  CONCLUSIONS
  Early GGT levels were much higher in neonates, especially preterm infants with GA of 31-35 weeks.
authors.affiliation: a Department of Pediatrics , Ulsan University Hospital, University of Ulsan College of Medicine , Ulsan , South Korea.
authors.forename: Dong Bin
authors.initials: DB
authors.lastname: Kim
authors.affiliation: a Department of Pediatrics , Ulsan University Hospital, University of Ulsan College of Medicine , Ulsan , South Korea.
authors.forename: Gina
authors.initials: G
authors.lastname: Lim
authors.affiliation: a Department of Pediatrics , Ulsan University Hospital, University of Ulsan College of Medicine , Ulsan , South Korea.
authors.forename: Ki Won
authors.initials: KW
authors.lastname: Oh
mesh_terms: D000328:Adult; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D007363:Intensive Care Units, Neonatal; D008099:Liver / Q000201:enzymology*; D008111:Liver Function Tests; D008297:Male; D012016:Reference Values; D012189:Retrospective Studies; D012737:Sex Factors; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D005723:gamma-Glutamyltransferase
keywords: Cholestasis; gestational age; preterm infants; sex