title: Stable-isotope dilution analysis of D- and L-2-hydroxyglutaric acid: application to the detection and prenatal diagnosis of D- and L-2-hydroxyglutaric acidemias.
abstract: A stable-isotope dilution assay has been developed for quantitation of D- and L-2-hydroxyglutaric acids in physiologic fluids. D- and L-2-hydroxyglutaric acids are separated as the O-acetyl-di-(D)-2-butyl esters. The method uses D,L-[3,3,4,4-2H4]-2-hydroxyglutaric acid as internal standard with ammonia chemical ionization, selected ion monitoring gas chromatography-mass spectrometry. For 13 patients with L-2-hydroxyglutaric aciduria, the concentrations of L-2-hydroxyglutaric acid were urine, 1283 +/- 676 mmol/mol creatinine (range, 332-2742; n = 12 patients); plasma, 47 +/- 13 mumol/L (range, 27-62; n = 8); cerebrospinal fluid, 62 +/- 30 mumol/L (range, 34-100; n = 6). In a child with D-2-hydroxyglutaric aciduria, the levels of D-2-hydroxyglutaric acid were urine, 1565 +/- 847 mmol/mol creatinine (range, 729-2668; n = 4); plasma, 61 +/- 14 mumol/L (range, 46-73; n = 3); cerebrospinal fluid, 15 and 25 mumol/L (n = 2). Control concentrations of D- and L-2-hydroxyglutaric acids were (D:L): urine (n = 18), 6.0 +/- 3.6 mmol/mol creatinine (range, 2.8-17): 6.0 +/- 5.4 (range, 1.3-19); plasma (n = 10), 0.7 +/- 0.2 mumol/L (range, 0.3-0.9): 0.6 +/- 0.2 (range, 0.5-1.0); cerebrospinal fluid (n = 10), 0.1 +/- 0.1 mumol/L (range, 0.07-0.3): 0.7 +/- 0.6 (range, 0.3-2.3). Investigation of control amniotic fluid (n = 10) revealed the following values (D:L): 1.2 +/- 0.4 mumol/L (range, 0.6-1.8): 4.0 +/- 0.7 (range, 3.1-5.2), suggesting the feasibility of prenatal diagnosis in families at risk.
authors.affiliation: Department of Pediatrics, Free University Hospital, Amsterdam, The Netherlands.
authors.forename: K M
authors.initials: KM
authors.lastname: Gibson
authors.forename: H J
authors.initials: HJ
authors.lastname: ten Brink
authors.forename: D S
authors.initials: DS
authors.lastname: Schor
authors.forename: R M
authors.initials: RM
authors.lastname: Kok
authors.forename: A H
authors.initials: AH
authors.lastname: Bootsma
authors.forename: G F
authors.initials: GF
authors.lastname: Hoffmann
authors.forename: C
authors.initials: C
authors.lastname: Jakobs
mesh_terms: D042964:Acyl-CoA Dehydrogenase; D000328:Adult; D001826:Body Fluids / Q000737:chemistry*; D002648:Child; D003903:Deuterium; D044943:Fatty Acid Desaturases / Q000172:deficiency*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis*; D005977:Glutarates / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D007201:Indicator Dilution Techniques; D008607:Intellectual Disability / Q000175:diagnosis / Q000196:embryology; D008297:Male; D008661:Metabolism, Inborn Errors / Q000175:diagnosis* / Q000196:embryology; D015394:Molecular Structure; D011296:Prenatal Diagnosis / Q000379:methods*; D013237:Stereoisomerism
chemical_list: D005977:Glutarates; C019417:alpha-hydroxyglutarate; D003903:Deuterium; D044943:Fatty Acid Desaturases; D042964:Acyl-CoA Dehydrogenase