title: Neonatal total bilirubin measurements: Still room for harmonization.
abstract: BACKGROUND
  Universal screening of total bilirubin in neonates is endorsed by experts from the American Academy of Pediatrics and is increasingly common. Methodological differences between diazo-based quantitation ("wet" chemistry) and reflectance spectrophotometric quantitation ("dry" chemistry) can lead to unnecessary treatment. A recent recalibration of the only commercially available "dry" chemistry assay was issued to reduce these differences. This study evaluated the post-recalibration bias between the two assay types.
  
  
  METHODS
  Method comparison of neonatal total bilirubin (Beckman AU680 vs Ortho-Clinical-Diagnostics Vitros) was achieved using freshly-drawn neonatal samples (n=239).
  
  
  RESULTS
  The Vitros produced neonatal bilirubin results with a 12.4% average positive bias compared to the AU680 total bilirubin results. The AU680 direct bilirubin reaction had 5.6% cross reactivity with unconjugated bilirubin.
  
  
  CONCLUSIONS
  Neonatal or total bilirubin quantitation remains unharmonized between platforms. Care should be taken to understand the bias of specific platforms.
authors.affiliation: Kaiser Permanente, TPMG Northern California Regional Laboratory, Berkeley, CA, USA. Electronic address: dina.n.greene@kp.org.
authors.forename: Dina N
authors.initials: DN
authors.lastname: Greene
authors.affiliation: Kaiser Permanente, TPMG Northern California Regional Laboratory, Berkeley, CA, USA.
authors.forename: Joy
authors.initials: J
authors.lastname: Liang
authors.affiliation: University of British Columbia, Department of Pathology and Laboratory Medicine, Vancouver, BC, Canada.
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Holmes
authors.affiliation: Kaiser Permanente, TPMG Northern California Regional Laboratory, Berkeley, CA, USA.
authors.forename: Ann
authors.initials: A
authors.lastname: Resch
authors.affiliation: Kaiser Permanente, TPMG Northern California Regional Laboratory, Berkeley, CA, USA.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Lorey
mesh_terms: D001663:Bilirubin / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn
chemical_list: D001663:Bilirubin
keywords: AU680; Neonatal hyperbilirubinemia; Total and direct bilirubin; Universal screening; Vitros