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.
Quinolinic acid forms along a side road of tryptophan metabolism and is inflammatory in the brain, acting as an excitotoxin that ramps up with immune activation.



