Pathology of peripheral nerves in metachromatic leucodystrophy. A comparative study of ten cases

Results of qualitative and quantitative studies on 1 to 13 peripheral nerves from 10 cases (6 late infantile, 2 juvenile and 2 adult cases) of metachromatic leucodystrophy (MLD) are reported. Peripheral nerve biopsies are still useful despite the arylsulphatase A assays on leucocytes and cultured fibroblasts, since they provide extremely rapid and reliable diagnostic information. The following points are investigated: (1) are there differences in the severity and characteristics of demyelination according to MLD subtypes; (2) are there major differences in various nerves of one patient; (3) are some inclusions characteristic of a given MLD subtype; (4) is there a direct relationship between demyelination and storage of characteristic inclusions? While question 1 can be answered positively, the three following ones must receive a negative or at best an equivocal answer.