Laboratory analysis of organic acids by GC/MS: technical support

Organic acid disorders are inherited metabolic disorders in which organic acids accumulate in tissues and biological fluids of affected individuals. Organic acids are extracted from urine using organic solvents or ion exchange methods, and their presence and abundance are determined by gas chromatography¿mass spectrometry (GC-MS). Because these procedures require expensive equipment and qualified professionals, diagnosis of organic acidemias is generally available only at a few reference centers. The typical assay is performed by gas chromatography¿mass spectrometry. This technical support was developed to provide guidance for laboratory practices in organic acid analysis, interpretation, and reporting.