What is Krabbe disease?

Krabbe disease, also called globoid cell leukodystrophy, is a rare genetic disorder that affects the brain and the nerves outside of the brain and spinal cord (peripheral nerves). It is a type of leukodystrophy, a group of conditions that affect the white matter of the brain and damage the myelin sheath — the protective coating around nerve cells in the brain and spinal cord. Myelin helps messages travel quickly between cells in the brain and body. 

Causes of Krabbe disease

People with Krabbe disease are born with a change in a gene called GALC. This gene makes a protein that helps break down a fatty substance called psychosine. When the body doesn’t make enough of this protein, psychosine builds up and damages the cells that make myelin, the protective coating around the nerves. Without healthy myelin, signals from the brain slow down or stop, causing serious nerve problems. 

Signs and symptoms of Krabbe disease

There are two forms of Krabbe disease, based on when symptoms begin: infantile (symptoms start before 12 months of age) and later-onset (symptoms start after 12 months of age). 

In infants, symptoms can include: 

• Extreme irritability
• Stiff muscles
• Trouble feeding and acid reflux (when stomach acid comes up)
• Developmental delays and loss of skills (called regression)
• Staring spells
• Signs of nerve damage

In children over 12 months of age, symptoms can include:

• Developmental delays and loss of skills (called regression)
• Stiff muscles
• Vision problems
• Seizures
• Signs of nerve damage

Testing and diagnosis

In addition to looking at physical symptoms, diagnosing Krabbe disease involves several tests:

• A brain MRI (magnetic resonance imaging) can show patterns in brain tissue that are typical of Krabbe disease.
• Tests of the blood or cerebrospinal fluid (the clear fluid around the brain and spinal cord), called biochemical tests, check the activity level of the protein galactocerebrosidase and measure the level of the fatty substance psychosine in the body.
• Electrophysiologic tests, like a nerve conduction study or brainstem auditory evoked response (BAER), check how fast signals travel through the nerves in the body. If the signals are slower than normal, it may help doctors diagnose Krabbe disease.
• Genetic testing looks for changes in the gene linked to Krabbe disease. This test is done from a blood or saliva sample or a cheek swab. The results, combined with other tests, can lead to a diagnosis of Krabbe disease.

Together, results from these tests give a clear picture and help confirm the diagnosis.

Treatment for Krabbe disease

There is no known cure for Krabbe disease, but there are treatments that may change the progression of the disease. These include:

Stem cell transplant

A stem cell (bone marrow) transplant may help slow or stop the progression of Krabbe disease, especially if it is done early, when doctors first see changes in the brain on an MRI. This treatment requires a donor match, either from a family member or a bone marrow registry. 

Individualized treatment plans

If a child isn’t eligible for a stem cell transplant, other treatments can help manage symptoms and keep them as comfortable as possible. Each child’s care plan is different, based on their unique needs.

Some children with Krabbe disease may need help with breathing. Others might need feeding therapy or special diets. Seizures can often be controlled with medication.

Children with Krabbe disease should also be monitored for:

• Feeding, growth and weight changes
• Bone issues, such as scoliosis, dislocated joints and low bone density, which are linked to motor issues in Krabbe disease
• Vision changes, which may need testing by an eye doctor (ophthalmologist)
• Nerve damage, which can be discovered through nerve conduction studies

If any of these conditions are found, pediatric subspecialists can help treat them. Many children with Krabbe disease also benefit from physical, occupational and speech therapy to combat challenges caused by the disease.

Follow-up

Children with Krabbe disease need regular monitoring by neurologists, as well as ongoing therapy and coordinated care by other medical subspecialists as needed. At Children’s Hospital of Philadelphia (CHOP), families have access to advanced, multidisciplinary care, delivered by clinicians with deep expertise in leukodystrophies, all within a compassionate, family-centered environment.

Long-term outlook for children with Krabbe disease

Krabbe disease is a progressive, life-limiting disease, with symptoms that worsen over time. However, there are treatments that can improve a child’s quality of life. CHOP is one of the premiere institutions for leukodystrophy care and a designated Center of Excellence. Our ongoing research efforts aim to enhance outcomes for children with Krabbe disease and offer families hope for the future of leukodystrophy care.