Format

Send to

Choose Destination
Mol Genet Metab. 2014 Jan;111(1):52-4. doi: 10.1016/j.ymgme.2013.11.005. Epub 2013 Nov 19.

Surprising causes of C5-carnitine false positive results in newborn screening.

Author information

1
Biochemical Genetics Laboratory, Human Genetics, CHU Liege, University of Liege, Belgium. Electronic address: F.Boemer@chu.ulg.ac.be.
2
Biochemical Genetics Laboratory, Human Genetics, CHU Liege, University of Liege, Belgium.
3
Neonatal Intensive Care Unit, University of Liege, Centre Hospitalier Régional de la Citadelle, Liege, Belgium.
4
Metabolic Unit, Human Genetics, CHU Liege, University of Liege, Belgium.

Abstract

During an 18-month period, we noticed an alarming increase of newborn screening false positivity rate in identifying isovaleric acidemia. In 50 of 50 newborns presenting elevated C5-carnitine, we confirmed the presence of pivaloylcarnitine. Exogenous pivalate administration had been previously identified as the causal agent of this concern. No pivalic-ester prodrug is commercially available in Belgium, but pivalic derivates are also used in the cosmetic industry as emollient under the term "neopentanoate". We have identified neopentanoate-esters in a nipple-fissure unguent that was provided to young mothers. Ceasing distribution of this product hugely reduced the C5-carnitine false positivity rate.

KEYWORDS:

C5-carnitine; False positive; Inborn error of metabolism; Mass spectrometry; Newborn screening; Pivalic acid

PMID:
24291264
DOI:
10.1016/j.ymgme.2013.11.005
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center