Follow-up of a child with hypoacetylaspartia.

We provide a 5-year follow-up of a patient previously reported to have no NAA signal on neurospectroscopy. At 8 years this boy was found to have profound neurological dysfunction: he had truncal ataxia, no expressive speech, behaviour abnormalities, secondary microcephaly and cognitive achievements corresponding to less than 12 months of age. He started to have generalized seizures at 5 years 9 months. Although not directly proven we assume an inborn error of NAA metabolism, possibly a defect of the anabolic enzyme L-aspartate N-acetyltransferase (EC 2.3.1.17).