Open AccessA newborn screening approach to diagnose 3‐hydroxy‐3‐methylglutaryl‐CoA lyase deficiency
Author(s) -
Václavík Jan,
Mádrová Lucie,
Kouřil Štěpán,
de Sousa Julie,
Brumarová Radana,
Janečková Hana,
Jáčová Jaroslava,
Friedecký David,
Knapková Mária,
Kluijtmans Leo A. J.,
Grünert Sarah C.,
Vaz Frédéric M.,
Janzen Nils,
Wanders Ronald J. A.,
Wevers Ron A.,
Adam Tomáš
Publication year - 2020
Publication title -
jimd reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.412
H-Index - 25
ISSN - 2192-8312
DOI - 10.1002/jmd2.12118
Subject(s) - newborn screening , tandem mass spectrometry , metabolomics , chemistry , mass spectrometry , dried blood spot , orbitrap , spots , chromatography , medicine , biochemistry
3‐Hydroxy‐3‐methylglutaryl‐coenzyme A lyase deficiency (HMGCLD) is a rare autosomal recessively inherited metabolic disorder. Patients suffer from avoidable neurologically devastating metabolic decompensations and thus would benefit from newborn screening (NBS). The diagnosis is currently made by measuring dry blood spot acylcarnitines (C5OH and C6DC) followed by urinary organic acid profiling for the differential diagnosis from several other disorders. Using untargeted metabolomics (reversed‐phase UHPLC coupled to an Orbitrap Elite hybrid mass spectrometer) of plasma samples from 5 HMGCLD patients and 19 age‐matched controls, we found 3‐methylglutaconic acid and 3‐hydroxy‐3‐methylglutaric acid, together with 3‐hydroxyisovalerylcarnitine as the most discriminating metabolites between the groups. In order to evaluate the NBS potential of these metabolites we quantified the most discriminating metabolites from untargeted metabolomics in 23 blood spots from 4 HMGCLD patients and 55 controls by UHPLC tandem mass spectrometry. The results provide a tool for expanded NBS of HMGCLD using tandem mass spectrometry. Selected reaction monitoring transition 262/85 could be used in a first‐tier NBS analysis to screen for elevated 3‐hydroxyisovalerylcarnitine. In a positive case, a second‐tier analysis of 3‐hydroxy‐3‐methylglutaric acid and 3‐methylglutaconic acid in a dry blood spot using UHPLC tandem mass spectrometry instruments confirms the diagnosis. In conclusion, we describe the identification of new diagnostic biomarkers for HMGCLD and their application in NBS in dry blood spots. By using second‐tier testing, all patients with HMGCLD were unequivocally and correctly diagnosed.