title: Predictive value of cord blood bilirubin for hyperbilirubinemia in neonates at risk for maternal-fetal blood group incompatibility and hemolytic disease of the newborn.
abstract: OBJECTIVE
  To determine the predictive ability of cord blood bilirubin (CBB) for hyperbilirubinemia in a population at risk for maternal-fetal blood group incompatibility and hemolytic disease of the newborn.
  
  
  METHODS
  This is a single center retrospective case-control study. Cases received phototherapy; controls did not. Cases were matched 1:3 to controls by gender and treating physician. Inclusion criteria included: ≥35 weeks gestation, CBB, and one or more total serum bilirubin (TSB) concentrations. The primary outcome was CBB. Secondary outcomes were a TSB >75th percentile, length of stay, and neonatal intensive care unit admission. The prognostic ability of CBB for phototherapy and TSB >75th percentile was assessed using area under the receiver operating characteristic (ROC) curve. Logistic regression analyses were performed to determine predictors for phototherapy and TSB >75th percentile.
  
  
  RESULTS
  When compared to controls (n = 142), cases (n = 54) were more likely to have a positive Coombs' test (82% vs. 41% , p <  0.001) and TSB >75th percentile (85% vs. 21% , p <  0.001). When compared to controls, cases had a higher mean (±SD) CBB (2.5 ± 0.5 vs. 1.8 ± 0.4 mg/dL, p <  0.001). The area under the ROC curve (±SEM) for CBB for phototherapy and TSB >75th percentile was 0.87 ± 0.03 (p <  0.001, 95% CI 0.82, 0.93) and 0.87 ± 0.03 (p <  0.001, 95% CI 0.82, 0.92), respectively.
  
  
  CONCLUSIONS
  In this study, the mean CBB concentration was higher in neonates who received phototherapy compared to those who did not. CBB concentrations may help predict severe hyperbilirubinemia and phototherapy in a population at risk for hemolytic disease of the newborn.
authors.affiliation: Department of Pediatrics, Division of Neonatology and Developmental Biology, Neonatal Research Center, David Geffen School of Medicine, University of California, and Mattel Children's Hospital at UCLA, Los Angeles, CA, USA.
authors.forename: K
authors.initials: K
authors.lastname: Calkins
authors.affiliation: Department of Pediatrics, Division of Neonatology and Developmental Biology, Neonatal Research Center, David Geffen School of Medicine, University of California, and Mattel Children's Hospital at UCLA, Los Angeles, CA, USA.
authors.forename: D
authors.initials: D
authors.lastname: Roy
authors.affiliation: Department of Pediatrics, Division of Neonatology and Developmental Biology, Neonatal Research Center, David Geffen School of Medicine, University of California, and Mattel Children's Hospital at UCLA, Los Angeles, CA, USA.
authors.forename: L
authors.initials: L
authors.lastname: Molchan
authors.forename: L
authors.initials: L
authors.lastname: Bradley
authors.affiliation: Department of Medicine, Statistics Core, David Geffen School of Medicine, University of California and Mattel Children's Hospital at UCLA, Los Angeles, CA, USA.
authors.forename: T
authors.initials: T
authors.lastname: Grogan
authors.affiliation: Department of Medicine, Statistics Core, David Geffen School of Medicine, University of California and Mattel Children's Hospital at UCLA, Los Angeles, CA, USA.
authors.forename: D
authors.initials: D
authors.lastname: Elashoff
authors.affiliation: Department of Pediatrics, Division of Neonatology and Developmental Biology, Neonatal Research Center, David Geffen School of Medicine, University of California, and Mattel Children's Hospital at UCLA, Los Angeles, CA, USA.
authors.forename: V
authors.initials: V
authors.lastname: Walker
mesh_terms: D000017:ABO Blood-Group System; D001663:Bilirubin / Q000097:blood*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006932:Hyperbilirubinemia / Q000097:blood* / Q000175:diagnosis*; D007231:Infant, Newborn; D008297:Male; D015997:Neonatal Screening / Q000295:instrumentation*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment
chemical_list: D000017:ABO Blood-Group System; D001663:Bilirubin
keywords: Bilirubin; hemolytic disease; neonates; phototherapy