title: Expanded newborn screening and confirmatory follow-up testing for inborn errors of metabolism detected by tandem mass spectrometry.
abstract: Newborn screening (NBS) of inborn errors of metabolism (IEM) is a coordinated comprehensive system consisting of education, screening, follow-up of abnormal test results, confirmatory testing, diagnosis, treatment, and evaluation of periodic outcome and efficiency. The ultimate goal of NBS and follow-up programs is to reduce morbidity and mortality from the disorders. Over the past decade, tandem mass spectrometry (MS/MS) has become a key technology in the field of NBS. It has replaced classic screening techniques of one-analysis, one-metabolite, one-disease with one analysis, many-metabolites, and many-diseases. The development of electrospray ionization (ESI), automation of sample handling and data manipulation have allowed the introduction of expanded NBS for the identification of numerous conditions on a single sample and new conditions to be added to the list of disorders being screened for using MS/MS. In the case of a screened positive result, a follow-up analytical test should be performed for confirmation of the primary result. The most common confirmatory follow-up tests are amino acids and acylcarnitine analysis in plasma and organic acid analysis in urine. NBS should be integrated with follow-up and clinical management. Recent improvements in therapy have caused some disorders to be considered as potential candidates for NBS. This review covers some of the basic theory of expanded MS/MS and follow-up confirmatory tests applied for NBS of IEM.
authors.affiliation: Faculty of Medicine, Department of Clinical Biochemistry, Akdeniz University, Antalya, Turkey. ozben@akdeniz.edu.tr
authors.forename: Tomris
authors.initials: T
authors.lastname: Ozben
mesh_terms: D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D008661:Metabolism, Inborn Errors / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D015997:Neonatal Screening; D053719:Tandem Mass Spectrometry