Tandem mass spectrometric assay of succinylacetone in urine for the diagnosis of hepatorenal tyrosinemia.
We describe an isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of succinylacetone (SA) in urine for the diagnosis of hepatorenal tyrosinemia (HT1). The method used 15N-labeled 5(3)-methyl-3(5)-isoxazole propionic acid as internal standard. Urine samples were oximated with hydroxylamine hydrochloride at 80 degrees C, extracted by solvent-solvent extraction, and followed by derivatization of the butyl ester. The butylated isoxazole derivatives of SA and its internal standard were detected and quantified using positive ion electrospray LC-MS/MS with selected reaction monitoring. The turnaround time between injections was 10 min. Calibration curves were linear over the range of 0.0633-63.3 micromol/L. The intra- and interday assay variations were less than 7%. Mean recoveries of SA at three different concentrations ranged from 96 to 109%. During the course of this study, we identified 12 new patients with HT1 and applied this method to follow up the treatment of 4 of these patients as well as previously diagnosed HT1 patients.
Rashed
Mohamed S
MS
Department of Genetics, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, Riyadh 11211, Saudi Arabia. rashed@kfshrc.edu.sa
Al-Ahaidib
Lujane Y
LY
Al-Dirbashi
Osama Y
OY
Al Amoudi
Mohammad
M
Al-Sayed
Moeen M A
MM
Rahbeeni
Zuhair
Z
Al-Hassnan
Zuhair
Z
Al-Dbaas
Abeer
A
Al-Owain
Mohamed
M
Ni Luanaigh
Michelle
M
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003512:Cyclohexanones / Q000627:therapeutic use; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D006537:Heptanoates / Q000652:urine*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D013058:Mass Spectrometry; D008875:Middle Aged; D015997:Neonatal Screening / Q000379:methods; D009579:Nitrobenzoates / Q000627:therapeutic use; D015203:Reproducibility of Results; D020176:Tyrosinemias / Q000188:drug therapy / Q000652:urine*
D003512:Cyclohexanones; D004791:Enzyme Inhibitors; D006537:Heptanoates; D009579:Nitrobenzoates; C020804:succinylacetone; C077073:nitisinone