What is Krabbe Disease?
Globoid Cell Leukodystrophy, commonly known as Krabbe (crab-ay) Disease, is a genetic disorder that affects the central and peripheral nervous systems.
Those affected by Krabbe typically appear healthy until onset, or when an individual experiences symptoms, of the disease. Onset can vary from the first few weeks or months of life (Early Infantile Onset) into adulthood (Adult Onset).
Those who suffer from Krabbe Disease have a deficiency of an important enzyme called Galactosylceramidase (GALC).
Krabbe Disease is both a Leukodystrophy and Lysosomal Storage Disorder (LSD). Leukodystrophies are characterized as degenerative diseases of the white matter of the brain. LSDs occur when a part of the cell, called the lysosome, does not function properly. In a healthy individual, enzymes break down material in the lysosomes, however, if the body does not produce enough of a specific enzyme (ex: GALC), material builds up and becomes toxic.
What parts of the body are affected?
Krabbe Disease affects both the central and peripheral nervous systems, which are responsible for all of the body’s voluntary and involuntary movements.
The central nervous system is made up of the nerves within the brain and spinal cord and is the primary control center of the body.
The peripheral nervous system’s primary function is to carry information from the brain and spinal cord throughout the body to the limbs and organs.
What are the different forms of Krabbe Disease?
Early Infantile Krabbe Disease (EIKD)
Early Infantile Krabbe Disease is the most severe form and is often initially misdiagnosed as colic, reflux, food/milk allergy, or even cerebral palsy.
Affected babies begin to show symptoms, including severe irritability, feeding issues, stiffness and unmet developmental milestones, within the first months of life.
Symptoms: Extreme irritability (excessive crying), stiffness, decline in motor skills, loss of previously attained milestones, difficulty in feeding, seizures, arching of the back, jerking of the arms and/or legs.
Later Onset Infantile Krabbe Disease
Those with Later Onset Krabbe Disease begin to show symptoms between 6 months and 3 years of age. Symptoms are similar to those described in Early Infantile Krabbe Disease.
Symptoms: General irritability (excessive crying), stiffness, decline in motor skills, loss of previously attained milestones, difficulty in feeding, seizures, arching of the back, jerking of the arms and/or legs.
Juvenile Onset Krabbe Disease and Adult Onset Krabbe Disease
Those with Juvenile Onset Krabbe Disease typically show an initial regression of motor skills at 3 years of age or later. After the initial decline, the disease progresses slowly, often lasting years.
Adult Onset Krabbe Disease often results in initial vision problems, generally followed by muscle stiffness and difficulty walking. It is possible that Adult Onset Krabbe Disease can be misdiagnosed as multiple sclerosis.
Symptoms: Progressive loss of vision, difficulty walking (ataxia), loss of manual dexterity, muscle weakness
Is there a treatment for Krabbe Disease?
Yes, when diagnosed early.
Individuals diagnosed before the disease is too far progressed may be eligible for a Cord Blood Transplant. Through this procedure, stem cells from umbilical cord blood are given to the affected patient in order to slow the progression of the disease. These stem cells come from umbilical cords that are stored after live, healthy births of unaffected donors. To learn more, please visit the Carolinas Cord Blood Bank.
Unfortunately, myelin that has already been damaged by the disease cannot be repaired by this treatment. This is why it is important for Krabbe Leukodystrophy to be detected as early as possible, ideally through each state including Krabbe in their newborn screening program.
What if my child was diagnosed too late for a transplant?
Tragically, unless a child is born in a state that screens for Krabbe at birth, or has a known family history of the disease, the vast majority of children are diagnosed after they are symptomatic and too far progressed to benefit from a transplant.
However, numerous families have found that their child’s symptoms and pain can be managed through various medications, adaptive equipment and therapies – including physical, respiratory, occupational, and speech.
To learn more about experiencing the joy of living with a child affected by Krabbe Disease, visit the Hope for Life section of our website.
Why is the GALC enzyme needed in the body?
GALC is needed for the body to make normal myelin in the central and peripheral nervous systems and to break down material in the lysosomes. When too little GALC is produced, it causes toxicity in the brain, leading to myelin loss. This changes brain cells and causes neurological damage.
Why is myelin so important in the nervous systems?
Myelin is the protective covering of the nerve cells and acts like insulation surrounding an electric wire. Myelin is needed for the transmission of information from neurons. When myelin is damaged, some communication is lost during transmission. This results in the loss of voluntary and involuntary function in the body. Currently, there is no known method to reverse damage to myelin.
How do you get Krabbe Disease?
Krabbe Disease is genetic, which means that it is an inherited disorder. Krabbe is an autosomal recessive disorder, meaning that if both parents are carriers of the disease, each child has a 1 in 4 chance of developing Krabbe.
When both parents pass on a specific mutated gene, their child has a 25% chance of being affected by the disease, a 25% chance of neither being a carrier or affected and a 50% chance of being a carrier, like the parent.
Could other children in the family also have Krabbe Disease?
If both parents are carriers, each child has a 1 in 4 chance of being affected. If not affected, other children in the family could also be a carrier of the gene causing the disease.
To determine if other children in the family are affected by Krabbe Disease, it is best to consult with your genetic counselor or your child’s physician.
How is Krabbe Disease diagnosed?
Krabbe Disease is diagnosed through a series of tests. Oftentimes a blood test is used to determine the level of GALC enzyme activity. Other tests may include a MRI, CT, nerve conduction study and genetic testing for mutation analysis.
Although newborn screening for Krabbe is available in some states and through Supplemental Newborn Screening, it is NOT a diagnostic test, however, newborn screening can lead to a proper and early diagnosis upon confirmatory testing.
What research is being done to find better treatments & a cure for Krabbe Disease?
Hunter’s Hope is committed to funding research for better treatments and a cure for Krabbe and other Leukodystrophies. To learn more about the groundbreaking research currently underway, visit the Research section of our website.
Families affected by Krabbe are an integral part of advancing research for this disease. To learn more about how your family can participate in our World Wide Registry for Krabbe Disease, contact us here.
Additional Resources for Families
Additional Resources for Medical Professionals
American College of Medical Genetics Krabbe Disease ACT SHEET for Medical Professionals
Mayo Clinic: Krabbe Disease
National Institutes of Health: Krabbe Disease
NIH Gene Reviews: Krabbe Disease
US National Library of Medicine: Krabbe Disease
New York State Department of Health: Newborn Screening for Krabbe Disease