title: Postnatal serum concentrations of endogenous free fatty acids in newborns admitted to the neonatal intensive care unit: effects on unbound bilirubin.
abstract: BACKGROUND
  Few studies have reported the characterization of postnatal serum concentrations of endogenous free fatty acids (FFAs) in high-risk newborns and their effects on unbound bilirubin (UB).
  
  
  METHODS
  Serum concentrations of FFA, albumin (Alb), UB and total bilirubin (TB) were measured in 713 samples obtained within 5 days after birth from 439 newborns without intravenous lipid supplementation admitted to the neonatal intensive care unit (NICU). Serum FFA was reported as the day-specific percentile-based curve. Serum FFA and FFA/Alb ratios were compared in term and preterm patients. To assess the impact of FFA on UB, daily changes in FFA/Alb and UB/TB ratios were compared in term patients without receiving phototherapy or any drugs, and linear regression analysis was performed between FFA/Alb ratio and serum UB concentration or UB/TB ratio using 140 sera with hyperbilirubinemia of term and preterm patients.
  
  
  RESULTS
  A percentile-based curve showed that serum FFA peaked at 1 day of age and progressively decreased. Serum FFA and the FFA/Alb ratio were significantly higher in term than in preterm patients at birth and 1 and 3 days of age. FFA/Alb ratio significantly changed over 5 days after birth, but UB/TB ratio remained constant. FFA/Alb ratio did not correlate with serum UB concentration or UB/TB ratio in sera with hyperbilirubinemia.
  
  
  CONCLUSIONS
  We assessed postnatal concentrations of serum FFA in a large number of high-risk newborns admitted to the NICU. The concentration of endogenous FFAs in newborns admitted to the NICU was not rising until it influenced UB.
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Tsubasa
authors.initials: T
authors.lastname: Koda
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan ichim@med.kobe-u.ac.jp.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Morioka
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yokota
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kurokawa
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Fujita
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Miwako
authors.initials: M
authors.lastname: Nagasaka
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Matsuo
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Shibata
authors.affiliation: Department of Clinical Laboratory, Kobe University Hospital, Kobe, Japan.
authors.forename: Itsuko
authors.initials: I
authors.lastname: Sato
authors.affiliation: Department of Clinical Laboratory, Kobe University Hospital, Kobe, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kawano
authors.affiliation: Department of Obstetrics and Gynecology, Kobe University Hospital, Kobe, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Yamada
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Department of Pediatrics, Kobe University Hospital, Kobe, Japan.
authors.forename: Kazumoto
authors.initials: K
authors.lastname: Iijima
mesh_terms: D001663:Bilirubin / Q000097:blood*; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D006801:Humans; D006932:Hyperbilirubinemia / Q000097:blood; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D007363:Intensive Care Units, Neonatal; D008297:Male; D012307:Risk Factors; D012709:Serum Albumin / Q000032:analysis
chemical_list: D005230:Fatty Acids, Nonesterified; D012709:Serum Albumin; D001663:Bilirubin
keywords: Clinical studies; analytes; bilirubin; lipids