A case of Canavan disease: the first biochemically proven case in a Japanese girl.

Canavan disease (CD) has only been diagnosed on autopsy or brain biopsy, however, specific biochemical markers, such as N-acetylaspartic acid (NAA) and aspartoacylase activity, have recently been described in CD. We report a case of CD having the above biochemical markers. High levels of NAA were found in her urine, serum and CSF. Fibroblasts did not exhibit aspartoacylase activity. Clinically, she presented progressive psychomotor retardation, cerebellar signs, pyramidal signs and relative megalencephaly. CT and MRI showed findings of leukodystrophy. The evoked potentials showed widespread involvement in the brainstem. Magnetic resonance spectra showed a high level of NAA in the white matter. In Japan, this case is the first of CD determined on the basis of biochemical markers.