Synonyms: Arylsulfatase A deficiency | MLD
A rare lysosomal disease characterized by accumulation of sulfatides in the central and peripheral nervous system due to deficiency of the enzyme arylsulfatase A leading to demyelination. Three clinical subtypes can be distinguished based on the age of onset: late infantile juvenile and adult. Lead symptoms are deterioration in motor or cognitive function or behavioral problems depending on the subtype all eventually culminating in a decerebrated state and death after a highly variable disease course and duration. Mode of inheritance is autosomal recessive.
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview. Reference: Access aggregated data from Orphanet at Orphadata. Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http://www.orphadata.org. Data version February 2026
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Metachromatic leukodystrophy?
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Advocacy Organizations
Aicardi-Goutieres Syndrome Advocacy Association
AGSAA is a global coalition of deeply dedicated parent advocates working alongside clinicians, researchers, and scientists. We are united in our desire to improve the lives of individuals and families living with Aicardi-Goutières Syndrome and those yet to be diagnosed. Everything we do reflects a sense of urgency to rescue patient potential and preserve quality of life through accelerating research and providing timely emotional and educational support alongside evolving clinical care recommendations to affected families.
Alex, The Leukodystrophy Charity
Support and access to treatment for everyone living with leukodystrophy Provide support for those living with leukodystrophy, and their families/carers Raise awareness of leukodystrophy Improve best practice in prevention, diagnosis & treatment Support research initiatives
Canadian Society for Mucopolysaccharide & Related Diseases Inc.
The Canadian MPS Society is a charitable organization dedicated to supporting individuals and families affected by mucopolysaccharidoses (MPS) and related lysosomal storage disorders. We are helping families live their best lives.
Charcot-Marie-Tooth Association
Our mission … to support the development of new treatments for CMT, to improve the quality of life for people with CMT, and, ultimately, to find a cure. Our vision … a world without CMT. CMTA was started by patients in 1986, and to this day is powered by a community of patients who are engaged in helping carry out and support our mission.
Childhood Dementia Initiative
Our vision is for sustainable global health solutions for childhood dementia. This will be achieved through the following outcomes: - Treatments and cures available for children with dementia - Access to equitable and quality care for children with dementia and their families - Childhood dementia is a global health policy priority.
Cure LBSL
Our Mission Find a cure for LBSL, advance awareness of the disease, and support patients, families, and medical providers confronted with this ultra-rare condition.
Genetic Epilepsy Team Australia
Collaboration of research and care
Help Hope Live
Help Hope Live believes a medical crisis shouldn’t become a financial crisis. Help Hope Live supports community-based fundraising for people with unmet medical expenses and related costs due to cell and organ transplants or catastrophic injuries and illnesses. These efforts play a critical role in helping clients access the care and equipment they need to heal, live, and thrive.
Louisiana Metabolic Disorders Coalition
We support, educate, and advocate for patients & families affected by metabolic disorders.
Lysosomal Storage Disorders Society – Pakistan
LSD Society Pakistan is a registered Non-Profit organization set up by a group of parents dedicated and committed to improve the lives of Lysosomal Storage Disease patients in Pakistan by advocating for patients’ rights and creating awareness in general public. The objective of LSD Society is to advocate with the government and other stakeholders to establish a sustainable healthcare system
Lysosomal Storage Disorders Support Society
LSDSS endeavors to transform the life of children affected by rare Lysosomal Storage Disorders. Our mission is to increase awareness about the prevention of such disorders in future offspring as well as counsel the affected patients and families on how to cope with existing conditions, ensuring no patient or family living with an LSD ever feels alone.
MPS Society
The MPS Society supports families through difficult times and helps people living with rare diseases to live their lives to the full. Founded in 1982 and led by people directly affected by these diseases, we are the only registered charity in the UK which focusses on MPS (Mucopolysaccharide), Fabry and related conditions, a group of 27 rare, life-limiting genetic diseases.
Mississippi Metabolics Foundation
Our mission at Mississippi Metabolics Foundation (MMF) is to advocate, educate, and support families in MS affected by genetic metabolic disorders/inborn errors of metabolism (IEM's). MMF promotes initiatives and further advancements in legislation, education, research, clinical trials, studies, therapies, targeted treatments, and eventual cures for IEM’s and all rare diseases.
Rare Epilepsy Network (REN)
Improving outcomes of people with rare epilepsies through an innovative collaborative infrastructure that drives urgent, patient-centered research, educaiton and advocacy.
Syndromes Without A Name (SWAN) Australia
Provide information, support and advocacy to families caring for a child with an undiagnosed or rare genetic condition.
TNPO2 Foundation
Develop personalized therapeutics for ultra rare genetic neurodevelopmental diseases, especially those arising from mutations in the TNPO2 gene.
United Leukodystrophy Foundation
OUR MISSION is to provide support to the leukodystrophy community and enable platforms to accelerate improving patient quality of life and finding cures.
mld foundation
We C.A.R.E.® ... facilitating Compassion for families, increasing Awareness, influencing & funding Research, and promoting Education for metachromatic leukodystrophy, a very rare terminal genetic neuro-metabolic lysosomal disease where over half the cases affect infants.
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Clinical Trials
For a list of clinical trials in this disease area, please click here.