Neonatal Screening for Medium-Chain Acyl-CoA Deficiency—Insights and Unexpected Challenges

• Main Author: Esther M. Maier
• Format: Article
• Language: English
• Published: MDPI AG 2015-11-01
• Series: International Journal of Neonatal Screening
• Subjects: medium-chain acyl-CoA dehydrogenase; neonatal screening; newborn screening; tandem mass spectrometry; confirmation of positive screening results
• Online Access: http://www.mdpi.com/2409-515X/1/3/79

With the implementation of tandem mass spectrometry (MS/MS), neonatal screening for medium-chain acyl-CoA dehydrogenase (MCADD) has been introduced in many screening programs worldwide. Together with phenylketonuria, MCADD is the disorder most frequently diagnosed. Despite undeniable beneficial effects on morbidity and mortality, neonatal screening for MCADD effectively exemplifies the unexpected challenges of increased diagnosis by screening programs. MS/MS-based screening revealed an at least 2-fold higher incidence than expected with a considerable share of individuals showing mild biochemical alterations and/or novel mutations with unknown clinical significance. Whether these individuals are at lower risk to experience metabolic decompensations is a matter of ongoing debate. Defining patients, stratifying them according to their clinical risk, and adopting treatment protocols is an as yet unmet challenge in neonatal screening for MCADD.