title: Surveillance of extreme hyperbilirubinaemia in Denmark. A method to identify the newborn infants.
abstract: OBJECTIVE
  To describe the incidence of infants born at term or near-term with extreme hyperbilirubinaemia.
  
  
  METHODS
  The study period was between 1 January 2002 and 31 December 2005, and included all infants born alive at term or near-term in Denmark. Medical reports on all newborn infants with a total serum bilirubin concentration (TSB) > or = 450 micromol/L were obtained by linking laboratory data to the unique Danish personal identification number.
  
  
  RESULTS
  In total, 113 infants were included, that is, an incidence of 45/100,000 live births. Thirty-seven infants presented in hospital, 2 after home birth and the others after having been discharged. The maximum TSB was 485 (450-734) micromol/L (median [range]) and appeared latest amongst those infants admitted from home, but was not different from the maximum TSB of the nondischarged infants. Forty-three infants had symptoms of early-phase acute bilirubin encephalopathy; one infant had advanced-phase symptoms. Four infants received an exchange transfusion. ABO blood group incompatibility was present in 52 infants. Thirty-seven infants were of non-Caucasian descent.
  
  
  CONCLUSIONS
  A method to obtain the national epidemiological data is presented. The observed incidence of extreme hyperbilirubinaemia is higher than previously reported in Denmark. This is mainly due to a very sensitive method of identifying the study group.
authors.affiliation: Department of Paediatrics, University Hospital Skejby, Aarhus, Denmark. jvbjerre@dadlnet.dk
authors.forename: Jesper Vandborg
authors.initials: JV
authors.lastname: Bjerre
authors.forename: Jes Reinholdt
authors.initials: JR
authors.lastname: Petersen
authors.forename: Finn
authors.initials: F
authors.lastname: Ebbesen
mesh_terms: D003298:Coombs Test; D003718:Denmark / Q000453:epidemiology; D005865:Gestational Age; D006801:Humans; D006932:Hyperbilirubinemia / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology*; D015994:Incidence; D007231:Infant, Newborn; D008403:Mass Screening / Q000379:methods*; D011159:Population Surveillance / Q000379:methods*; D015995:Prevalence; D012720:Severity of Illness Index