Absence of N-acetylaspartate in the human brain: Impact on neurospectroscopy?

N‐acetylaspartate (NAA) contributes to the most prominent signal in proton magnetic resonance spectroscopy (1H‐MRS) of the adult human brain. We report the absence of NAA in the brain of a 3‐year‐old child with neurodevelopmental retardation and moderately delayed myelination. Since normal concentration of NAA in body fluids is hardly detectable, 1H‐MRS is a noninvasive technique for identifying neurometabolic diseases with absent NAA. This report puts NAA as a neuronal marker to question. Ann Neurol 2001;49:518–521