Treatment of MLD in

Metachromatic leukodystrophy (MLD) is a rare inherited lysosomal storage disease. ICD-10 code E75.2. The underlying cause is an autosomal recessive mutation in the ARSA gene on chromosome 22q13.33, leading to deficiency of the enzyme arylsulfatase A. Without active enzyme, sulfatides (components of myelin sheaths) accumulate in lysosomes of oligodendrocytes and Schwann cells, producing progressive demyelination of the central and peripheral nervous system. Incidence is 1 in 40000–160000 depending on the population. Three clinical forms are distinguished by age of onset. Late-infantile (the most severe, about 50–60% of cases) — manifestation at ages 1–2: regression of previously acquired motor skills, gradually — spasticity, epilepsy, loss of speech and cognition; mortality typically in childhood. Juvenile (10–20%) — onset at ages 4–14 with behavioral disturbances and gradual regression; slower progression. Adult (10–30%) — late onset with psychiatric symptoms, often misdiagnosed as schizophrenia; the slowest progression. Since 2020 gene therapy has been approved in Europe and then other countries (Libmeldy / atidarsagene autotemcel) — harvest of patient hematopoietic stem cells, ex vivo genetic modification to introduce a functional ARSA copy, and reinfusion. Applicable for presymptomatic late-infantile and early juvenile forms. This changes the MLD landscape — for the first time it is possible to stop progression. However the drug is not yet available in many countries and requires strict selection criteria. For families whose child is not eligible for gene therapy or where the drug is unavailable, the main resource is supportive rehabilitation. Our Huizhou program focuses on: specialized therapeutic exercise to slow functional decline and prevent secondary complications (contractures, pain, immobility); physiotherapy; occupational therapy for home adaptation; swallowing and speech work with a speech therapist as feasible. TCM — gentle approaches for general state, immunity support, sleep normalization. We always plan the program multidisciplinarily, with the pediatric neurologist and, if needed, a palliative care team. For families with an acceptable phenotype, we help with coordination for gene therapy (referral to specialized centers, preparation of documents for review).