[Diagnostic strategy of metachromatic leukodystrophy in Tunisia].

We recruited a 44-year-old woman who had a dementia with behavioral and personality troubles. A biochemical analysis which includes a qualitative study of urinary sulfatides by thin layer chromatography followed by the determination of the enzymatic activity of arylsulfatase A (ARSA) was performed. The Molecular analysis concerned the research of the most frequent mutations (459 +1 G> A, p.P426L, p.I179S). The profile that has revealed the presence of 3-O-sulfogalactosylceramide fraction was in favor of metachromatic leukodystrophy. The activity of arylsulfatase A was collapsed in the index case which confirmed the phenotype of the adult form of the diagnosed MLD. The molecular study showed the presence of the mutation p.I179S in the homozygous state in the index case.