Use of tandem mass spectrometry for multianalyte screening of dried blood specimens from newborns.
BACKGROUND
Over the past decade laboratories that test for metabolic disorders have introduced tandem mass spectrometry (MS/MS), which is more sensitive, specific, reliable, and comprehensive than traditional assays, into their newborn-screening programs. MS/MS is rapidly replacing these one-analysis, one-metabolite, one-disease classic screening techniques with a one-analysis, many-metabolites, many-diseases approach that also facilitates the ability to add new disorders to existing newborn-screening panels.


METHODS
During the past few years experts have authored many valuable articles describing various approaches to newborn metabolic screening by MS/MS. We attempted to document key developments in the introduction and validation of MS/MS screening for metabolic disorders. Our approach used the perspective of the metabolite and which diseases may be present from its detection rather than a more traditional approach of describing a disease and noting which metabolites are increased when it is present.


BACKGROUND
This review cites important historical developments in the introduction and validation of MS/MS screening for metabolic disorders. It also offers a basic technical understanding of MS/MS as it is applied to multianalyte metabolic screening and explains why MS/MS is well suited for analysis of amino acids and acylcarnitines in dried filter-paper blood specimens. It also describes amino acids and acylcarnitines as they are detected and measured by MS/MS and their significance to the identification of specific amino acid, fatty acid, and organic acid disorders.


CONCLUSIONS
Multianalyte technologies such as MS/MS are suitable for newborn screening and other mass screening programs because they improve the detection of many diseases in the current screening panel while enabling expansion to disorders that are now recognized as important and need to be identified in pediatric medicine.
Chace
Donald H
DH
Pediatrix Screening, PO Box 219, 90 Emerson Lane, Bridgeville, PA 15017, USA. donald_chace@pediatrix.com
Kalas
Theodore A
TA
Naylor
Edwin W
EW
D000592:Amino Acid Metabolism, Inborn Errors / Q000097:blood; D000596:Amino Acids / Q000097:blood; D001800:Blood Specimen Collection; D002331:Carnitine / Q000031:analogs & derivatives* / Q000097:blood; D006403:Hematologic Tests / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn; D008052:Lipid Metabolism, Inborn Errors / Q000097:blood; D013058:Mass Spectrometry / Q000379:methods*
D000596:Amino Acids; C116917:acylcarnitine; D002331:Carnitine