Rapid and sensitive detection of urinary 4-hydroxybutyric acid and its related compounds by gas chromatography-mass spectrometry in a patient with succinic semialdehyde dehydrogenase deficiency.
We describe the rapid and sensitive detection of 4-hydroxybutyric acid, which is a marker compound for succinic semialdehyde dehydrogenase (SSADH) deficiency. Urinary 4-hydroxybutyric acid and 3,4-dihydroxybutyric acid were targeted, quantified by gas chromatography-mass spectrometry after simplified urease digestion in which lactone formation from gamma-hydroxy acids is minimized. The recovery of 4-hydroxybutyric acid using this method was over 93%. 2,2-Dimethylsuccinic acid was used as an internal standard. The detection limit of this method was 1 nmol ml(-1) for both 4-hydroxybutyric acid and 3,4-dihydroxybutyric acid. The urinary concentrations of 4-hydroxybutyric acid and of 3,4-dihydroxybutyric acid from the patient with an SSADH deficiency were 880-3628 mmol mol(-1) creatinine (control; 3.3+/-3.3 mmol mol(-1) creatinine) and 810-1366 mmol mol(-1) creatinine (control; 67.4+/-56.2 mmol mol(-1) creatinine), respectively. The simplified urease digestion of urine is very useful for quantifying 4-hydroxybutyric acid and its related compounds in patients with 4-hydroxybutyric aciduria.
Division of Human Genetics, Medical Research Institute, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Ishikawa 920-0293, Japan. shinka@kanazawa-med.ac.jp
Toshihiro
T
Shinka
Yoshito
Y
Inoue
Morimasa
M
Ohse
Akira
A
Ito
Masaharu
M
Ohfu
Shinichi
S
Hirose
Tomiko
T
Kuhara
D000445:Aldehyde Oxidoreductases / Q000172:deficiency*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006885:Hydroxybutyrates / Q000652:urine*; D007223:Infant; D008661:Metabolism, Inborn Errors / Q000175:diagnosis / Q000652:urine*; D012680:Sensitivity and Specificity; D050644:Succinate-Semialdehyde Dehydrogenase
D006885:Hydroxybutyrates; C111420:4-hydroxybutyric acid; D000445:Aldehyde Oxidoreductases; C493643:ALDH5A1 protein, human; D050644:Succinate-Semialdehyde Dehydrogenase