A sensitive and selective analytical technique is described for the determination of N-acetylaspartic acid in body fluids using stable isotope dilution in combination with positive chemical ionization mass spectrometry with selected ion monitoring. Control mean and ranges have been established: in urine 19.5 and 6.6-35.4 μmol/mmol creat.; in plasma 0.44 and 0.17-0.81 μmol/L; in cerebrospinal fluid 1.51 and 0.25-2.83 μmol/L; and in amniotic fluid 1.27 and 0.30-2.55 μmol/L. In a patient with Canavan disease, N-acetylaspartic acid concentration was elevated 80-fold in urine and 20-fold in plasma compared to the control means. A subsequent pregnancy of the mother was monitored and the N-acetylaspartic acid concentration in the amniotic fluid was within the control range and a healthy child was born.

doi.org/10.1007/BF01799929, hdl.handle.net/1765/56379
Journal of Inherited Metabolic Disease
Department of Clinical Genetics

Jakobs, C., ten Brink, H., Langelaar, M., Zee, T., Stellaard, F., Macek, M. M., … Kleijer, W. (1991). Stable isotope dilution analysis of N-acetylaspartic acid in CSF, blood, urine and amniotic fluid: Accurate postnatal diagnosis and the potential for prenatal diagnosis of canavan disease. Journal of Inherited Metabolic Disease, 14(5), 653–660. doi:10.1007/BF01799929