Analysis of Acylcarnitine Ester for Neonatal Screening of Inborn Errors of Metabolism Using Tandem Mass-spectrometry

Summary.  Tandem mass-spectrometry has been introduced worldwide into neonatal screening programs for the quantitative analysis of acylcarnitine species and amino acids for the diagnosis of organic acidurias, defects of fatty acid oxidation, and amino acidopathies, respectively. Since April 2002 more than 200000 newborn infants have been screened in Austria using tandem mass-spectrometry. In this cohort 37 infants with amino acidopathies and 38 infants with fatty acid oxidation defects or organic acidurias have been diagnosed. The overall incidence of these disorders is 0.036%. The analysis of acylcarnitine species using tandem mass-spectrometry has enabled the diagnosis of infants with inborn errors of metabolism prior to clinical presentation and to initiate therapy early enough to prevent long-term sequelae and to reduce mortality in these disorders.