ABSTRACT

Canavan disease (CD) is a rare autosomal recessively inherited leukodystrophy. The genetic defect related to the aspartoacylase gene. The clinical characteristics of CD include hypotonia, macrocephaly, developmental delay, and visual impairment within the first year of life. There is currently no cure for CD, however, new therapeutic modalities and gene therapy options are under investigation. Possible mechanisms in the pathogenesis include astrocytic edema caused by N-acetyl-L-aspartic acid (NAA) serving as a water pump and diminished acetate that is required for myelin synthesis. The current diagnostic approach to identify CD cases includes the demonstration of increased urinary NAA level, diminished or absence of enzyme activity in cultured skin fibroblasts, the loss of white matter including U-fibers in magnetic resonance (MR) imaging, NAA peak in MR spectroscopy (MRS), and genetic testing, in which more than 70 mutations have been identified. Among these diagnostic approaches, the NAA peak detected with the use of MRS is highly characteristic of CD and is the cornerstone in early diagnosis.