Tandem mass spectrometry and genetic variant analysis of four neonates with very long chain acyl-coenzyme A dehydrogenase deficiency

Abstract

To analyze the clinical features and genetic variants in four neonates with very long chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency. Neonates with a tetradecenoylcarnitine (C14:1) concentration at above 0.4 μmol/L in newborn screening were recalled for re-testing. Four neonates were diagnosed with VLCAD deficiency by MS-MS and genetic testing, and their clinical features and genotypes were analyzed. All cases had elevated blood C14:1, and the values of first recalls were all lower than the initial test. In 2 cases, the C14:1 had dropped to the normal range. 1 case has remained at above 1 μmol/L after the reduction, and the remainder one case was slightly decreased. In total eight variants of the ADACVL genes were detected among the four neonates, which included 5 missense variants and 3 novel variants (p.Met344Val, p.Ala416Val, c.1077+6T>A). No neonate showed salient clinical manifestations. Above findings have enriched the spectrum of ADACVL gene mutations and provided a valuable reference for the screening and diagnosis of VLCAD deficiency.