Development of a New Enzymatic Diagnosis Method for Very-long-chain Acyl-CoA Dehydrogenase Deficiency by Detecting 2-Hexadecenoyl-CoA Production and its Application in Tandem Mass Spectrometry-based Selective Screening and Newborn Screening in Japan

作者：Tajima Go^*; Sakura Nobuo; Shirao Kenichiro; Okada Satoshi; Tsumura Miyuki; Nishimura Yutaka; Ono Hiroaki; Hasegawa Yuki; Hata Ikue; Naito Etsuo; Yamaguchi Sew; Shigematsu Yosuke; Kobayashi Masao

来源：Pediatric Research, 2008, 64(6): 667-672.

DOI：10.1203/PDR.0b013e318187cc44

The introduction of tandem mass spectrometry (MS/ MS) has made it possible to screen for very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. To confirm the diagnosis in cases with an abnormal profile of blood acylcarnitines, we developed a new enzymatic assay method for determining dehydrogenase activity toward palmitoyl-CoA (C16:0) in lymphocytes. Using this method, the production of 2-hexadecenoyl-CoA (C16:1) by crude cell lysates can be directly quantified using high performance liquid chromatography (HPLC). We applied the assay to 7 myopathic patients, 7 hypoglycemic patients, and 2 presymptomatic newborns with elevated levels of tetradecenoylcarnitine (C14:1 AC) in blood, and found impaired VLCAD activity in all of the 7 myopathic patients and both of the 2 newborns. All of the 7 hypoglycemic patients had normal level of the enzyme activity. Results of the ACADVL gene analysis were in consistent with the enzymatic diagnosis. These results suggest that MS/MS-based screening for VLCAD deficiency using blood C14:1 AC as the indicator may show a considerably high false-positive rate in selective screening of symptomatic patients. Our practical enzymatic assay can be a useful test for the accurate diagnosis of VLCAD deficiency cases screened by MS/MS. (Pediatr Res 64: 667-672, 2008)

• 出版日期2008-12