Method: GC-MS (Gas Chromatography/Mass Spectrometry) measuring organic acid metabolites in urine (CLIA 17D0919496); not cleared or approved by the FDA. Results in mmol/mol creatinine. Not a stand-alone diagnosis; should be interpreted in clinical context.
MMA is normally cleared using vitamin B12, with the enzyme that processes it depending on B12, making elevations a reliable sign of low functional B12 supply.



