Metachromatic leukodystrophy: To screen or not to screen?

Metachromatic leukodystrophy (MLD) is a neurodegenerative lysosomal storage disorder caused by biallelic pathogenic variants in the gene encoding arylsulfatase A. Disease onset is variable (with late infantile, early and late juvenile, and adult forms) and treatment options depend on age and disease symptoms at onset. In the past, allo-hematopoietic stem cell transplantation (allo-HSCT) has been the best treatment option, following strict selection criteria. The outcome however is variable and morbidity remains high.