What is LBSL?

What is LBSL?

LBSL stands for Leukoencephalopathy with Brainstem and Spinal Cord Involvement and Lactate Elevation. LBSL is also known as the “Awesome Disease” because those battling this condition tend to be truly remarkable people.

LBSL is a rare genetic disorder that affects the brain and spinal cord. The exact number of people with this condition is unknown, and many may go undiagnosed, but based on reported cases, there are approximately 100 known patients worldwide.

First identified in 2004, LBSL is caused by mutations in the DARS2 gene, which provides the body with instructions for making an enzyme called mitochondrial aspartyl-tRNA synthetase. This enzyme is important for production of proteins in the mitochondria – the energy factories of our cells, which turn nutrients into energy. As a result of mutations in DARS2, certain parts of nervous system do not have sufficient energy to function properly affecting their function and the production of myelin. Much like the plastic coating around the wires in your home, myelin provides insulation to the nervous system and is essential for the transmission of signals from the brain to the rest of the body. More commonly known myelin disorders are Multiple Sclerosis (MS) and Parkinson’s disease.

What are the symptoms of LBSL?

According to the National Institutes of Health, most LBSL patients develop movement problems during childhood or adolescence. However, in some individuals, these problems do not develop until adulthood. Known symptoms include:

• Abnormal muscle stiffness and difficulty coordinating movements.
• Loss of the ability to sense the position of their limbs and vibrations
• Most individuals who show symptoms in childhood eventually require wheelchair assistance, sometimes as early as their teens, although the age varies.
• People with LBSL can have other signs and symptoms of the condition, such as seizures, speech difficulties, hand tremors, learning problems, or mild deterioration of mental functioning.
• Some people with this disorder are particularly vulnerable to severe complications following head trauma, which may trigger a loss of consciousness, other reversible neurological problems, or fever.

How is LBSL diagnosed?

LBSL is often first identified through MRI with contrast. Genetic testing is required to identify the DARS2 genetic mutation and confirm diagnosis. LBSL is inherited in an autosomal recessive manner, meaning most patients have inherited two copies of the mutated gene – one from each parent. Parents who are both carries of the DARS2 mutation have a 25% chance of having a child with LBSL.

Are there any treatments for LBSL?

Unfortunately, there are currently no definitive, long-term treatments for LBSL. The good news, however, is that research into LBSL is currently underway at the Kennedy Krieger Institute’s Moser Center for Leukodystrophies in Baltimore, Maryland. Launched in 2016, the project aims to develop novel new drug therapies for the treatment and hopefully cure LBSL.

Supportive therapies for LBSL patients include:

• Physical therapy and rehabilitation to improve motor function
• Antiepileptic drugs (AED)
• Special education
• Speech therapy

Some patients with LBSL take a combination of anti-oxidants, often referred to as a mitochondrial cocktail, under the guidance of a doctor in an effort to try to help energy production in the brain and spinal cord. While, the use of these anti-oxidants has not been systematically studied, and it is uncertain if their use will improve the long-term outcome of LBSL, some patients and families attribute positive results to the cocktail.