Metachromatic Leukodystrophy

Metachromatic Leukodystrophy (ML) is a rare genetic disorder characterized by severe vision loss. Most affected individuals have normal or near-normal visual acuity, but develop progressive retinal detachment with eventual blindness due to irreversible damage to the retina. Approximately 10% of cases are fatal. ML affects approximately 1 in every 200,000 births. The cause of ML is unknown; however, it seems to be caused by mutations in two genes: TYR and MYBPC3A. These genes are located on chromosome 16q11–13 and 15q21–24 respectively.

The first signs of ML usually appear between ages 5 and 20 years. However, some children may not experience any symptoms until adulthood or even later. Symptoms include visual disturbances such as double vision, blurred vision, tunnel vision, floaters and/or other light sensitivity problems. Other symptoms may include fatigue, weakness or numbness in one or both legs.

There is no specific test for ML.

In most cases the condition improves over time without treatment. Some patients will eventually recover completely from their sight loss. Others may require surgery to repair damaged retinas. There is no cure for this rare disease.

Current research for a cure is slow, with no treatment or cure currently available. However, it is thought that increasing the blood flow to the affected eye may help prevent further vision loss. This can be done by corticosteroid injections every three months. An ophthalmologist should be seen immediately if there are any signs of vision loss or an eye infection.

“Metachromatic leukodystrophy” is the name of a disease that can be diagnosed through genetic testing. If you or anyone you know have any of these symptoms mentioned above, consider getting it checked out.

Treatment and the course of the disease:

There is no specific treatment currently for this disease. However, ongoing research may lead to a treatment in the future. Many people live their entire life with this disease but vision loss may become so severe that it interferes with day-to-day activities.

An eye examination by an ophthalmologist (a medical doctor that specializes in the treatment of eye diseases and conditions) on a regular basis is recommended. If you notice any new symptoms, have your vision deteriorate or have any concerns about changes in your vision, you should contact your physician as soon as possible.

While there is no current treatment, there have been some advances in slowing down the progress of the disease.

Sources & references used in this article:

Lentiviral hematopoietic stem cell gene therapy benefits metachromatic leukodystrophy by A Biffi, E Montini, L Lorioli, M Cesani, F Fumagalli… – …, 2013 – science.sciencemag.org

Molecular basis of different forms of metachromatic leukodystrophy by A Polten, AL Fluharty, CB Fluharty… – … England Journal of …, 1991 – Mass Medical Soc

Metachromatic leukodystrophy–an update by V Gieselmann, I Krägeloh-Mann – Neuropediatrics, 2010 – thieme-connect.com

Psychiatric disturbances in metachromatic leukodystrophy: insights into the neurobiology of psychosis by TM Hyde, JC Ziegler, DR Weinberger – Archives of neurology, 1992 – jamanetwork.com

Molecular genetics of metachromatic leukodystrophy by V Gieselmann, J Zlotogora, A Harris… – Human …, 1994 – Wiley Online Library

Metachromatic leukodystrophy: diagnosis with samples of venous blood by AK Percy, RO Brady – Science, 1968 – science.sciencemag.org

Cerebroside sulfatase activator deficiency induced metachromatic leukodystrophy. by RL Stevens, AL Fluharty, H Kihara… – American journal of …, 1981 – ncbi.nlm.nih.gov

Allogeneic mesenchymal stem cell infusion for treatment of metachromatic leukodystrophy (MLD) and Hurler syndrome (MPS-IH) by ON Koc, J Day, M Nieder, SL Gerson… – Bone marrow …, 2002 – nature.com