How to Test for Krabbe Disease?
A neurologist or nervous systemThe nervous system of the body is made up of the Central Nervous System (CNS) and the Peripheral Nervous System (PNS). specialist, becomes part of the care team once a patient is thought to have a neurological concern. Your doctor may conduct one or more of the test/s listed below to confirm a diagnosis for Krabbe disease:
- An MRI to look for abnormalities and white matter degeneration.
- A Nerve Conduction Velocity (NCV) to measure the electrical activity of the nerves.
- An Electromyography (EMG)-often done in conjunction with NCV to measure electrical activity of muscles.
- An enzymeA protein needed by the body to break down certain substances by causing a biochemical reaction within the cells. In Krabbe disease, galactocerebrosidase is the deficient enzyme. Words that end in assay to detect low levels of GalactocerebrosidaseA specific enzyme that receives its instructions from the GALC gene. When the GALC gene isn’t working properly, the enzyme, galactocerebrosidase, is unable to break down certain fats called galactol (GALC) and high levels of psychosineDue to the enzyme deficiency in Krabbe disease, psychosine accumulates in the nervous system of affected individuals. Psychosine, a galactolipid, is a cytotoxic type of lipid, that has destructive pr in the blood.
- A Visual Evoked Potential (VEP) to test for abnormalities in the visual pathways that connect the eye to the brain.
- An Auditory Brainstem Response (ABR) to test for abnormalities in the auditory nerve.
Current Treatment and Clinical Care
Just as every snowflake has a unique composition, every baby, child, and adult living with Krabbe disease (KD) has unique medical concerns and needs. The information on this site is not intended or implied to be a substitute for professional medical advice, diagnosis, or treatment by your physician and/or KD specialists. The purpose of the information outlined below is to provide an overview about the treatment and care of those living with KD so informed conversations can take place.
The medical issues and symptoms of KD entail a long spectrum ranging with the most severe infantile onset cases to the diagnostic difficulties of late-onset, both significant and life-impacting. To best talk about treatment and care, we have divided the information into Infantile and Late-Onset or select from the menu below to quickly navigate to the section that best meets your needs.
- My child was diagnosed with Infantile Krabbe disease through newborn screening or because of known KD genetics in the family
- My child was diagnosed with Infantile Krabbe disease due to symptoms and diagnostic testing
- My child was diagnosed with Late-Onset Krabbe disease due to symptoms and diagnostic testing
Infantile Krabbe Disease
Prenatal/Newborn Screening Diagnosis
This section covers when a diagnosis of Krabbe disease (KD) occurs prior to birth, using amniocentesis, or completed at birth via the Newborn Screening Panel (NBS), or with an enzyme assay test. Parents screening a child in utero with amniocentesis are doing so due to a previous case of Krabbe disease within the immediate family. Screening for KD at birth is not common practice however, intermittent grassroots advocacy, carried out by affected families, has influenced some changes. In August 2006, when New York State instituted newborn screening for Krabbe disease, 3 other states have followed suit; Kentucky, Missouri, and Illinois.
If your child was diagnosed with infantile KD, a simple blood test was performed to detect a low level of galactocerebrosidase (or GALC for short), and a high level of psychosine. Further genetic testing likely occurred to confirm the presence of two copies of the disease-causing gene located on chromosome 14 along with its pathology. Now, you’re intensely searching for your options in treatment.
Treatment of Infantile KD
A hematopoietic stem cell transplantTypically this refers to a bone marrow transplant with the goal of replacing non-working cells with healthy working cells. Bone marrow is a rich source of stem cells that have the unique ability to (HSCTHematopoietic stem cell transplantation (HSCT), a type of transplantation using multipotent hematopoietic stem cells typically derived from bone marrow, peripheral blood, or that from umbilical cord b) in the first month of life is currently the only recommended treatment, to minimize the impact of the disease on the brain. Outcomes for KD are optimized when the HSCT is performed prior to a patient being symptomatic coupled with a very experienced transplant and clinical care team in KD. Having said this, it’s important for you to know that a HSCT is not a quick or easy medical procedure thus it’s very important you talk to an expert in KD and an expert in transplants to understand what the risks, benefits, and outcomes are for a KD patient undergoing a HSCT. It can also be incredibly insightful to talk with a parent whose utilized this treatment option for KD. You can read more about this in Connect with a Family.
Ongoing Care of Infantile
Treating infantile KD diagnosed early in life does not end after a hematopoietic stem cell transplant is performed. It’s important for you to know that transplanted children can encounter complications from the transplant such as, liver damage or interstitial pneumonia in addition to disease complications such as weakness or pain in their arms andor legs. Consequently, post-transplanted children need to be closely monitored by a team of experts to manage all medical, physical, and psychological aspects to ensure your child the best chance at a successful life.
Infantile Krabbe Disease
Symptomatic Diagnosis
In this section, you will learn about current treatments and clinical care for children diagnosed with infantile Krabbe disease(IKD) after the child is symptomatic. In this case, an infant or toddler will present with a variety of symptoms ranging from eating difficulties, abnormal irritability, arching of the body, sensitivity to loud sounds, delayed motor skills, loss of age-significant milestones, and much more. A delay in diagnosis is common with symptomatic IKD because children are unable to articulate physical or psychological changes.
Treatment and Ongoing Care
When your infant or child has been diagnosed with IKD after symptoms are present, a hematopoietic stem cell transplant (HSCT) is not recommended. More than a decade ago, HSCT was utilized as a treatment option for symptomatic children with IKD but the outcomes were unfavorable. Years of research have proven that symptomatic IKD patients endure additional health complications such as organ damage, permanent motor impairment, unresolvable infections, and even mortality, when HSCT is utilized.
While the treatment and care of a symptomatic child with IKD is difficult information to absorb, many options are available to support your child’s quality of life with IKD. At this time, it’s important to reach out to a medical expert appropriately trained in the treatment and management of KD. An experienced medical expert will assess the multisystem needs of your child by conducting neurodevelopmental assessments, providing medication management, initiating therapeutic services, counseling on optional surgical procedures, and employing palliative careSpecialized and supportive care for individuals with a serious illness with the goal of offering an improved quality of life, not only for the patient but the family as well. when needed. Below is list of treatment examples that are common in a newly diagnosed symptomatic child with IKD:
| Symptom | Treatment and Care |
| Difficulty Eating | Nasogastric tube (temporary) or NG NJ Feeding tube (permanent), G-tube |
| Severe Acid Reflux | Nissen Fundoplication-a laparoscopic procedure to resolve severe reflux |
| Irritability | Medication management recommended |
| Deterioration of Muscle Tone | Physical Therapy |
| Difficulty swallowingsecretions | Suction machine |
Late-Onset Krabbe Disease
Diagnosis
This section covers when a diagnosis of Krabbe disease occurs in children over the age of 3 and into adulthood. Symptoms of KD can be relatively slow to present in this form. The reason a slow progression of symptoms occurs can be attributed to 2 things: (1) 170 pathogenic variants have been identified accounting for different severities. (2) The older a patient reaches before symptoms are present, the more time a patient’s brain is given to reach full development. Completely myelinated cells in the human brain takes progressively more time to exhibit symptoms of deterioration. Below we have provided an overview of symptoms in late-onset KD:
| Childhood Symptoms | Adulthood Symptoms |
| Unable to feed themselves | Clumsy gait and movement |
| Vision Loss | Poor posture and fatigue |
| Limb weakness or difficulty walking | Vision or hearing loss |
| Speech delay or jumbled speech | Decreased coordination skills |
| Difficulty holding objects | SpasticityA term that describes muscles that are continually contracted and often described by patients as stiff and tight muscles. This stiffness and tightness can interfere with many activities of daily livin; muscles are continuously contracted |
Treatment of Late-Onset KD
The common health issues related to Krabbe disease are known to be misconstrued as other debilitating conditions such as Lyme’s disease, chronic fatigue syndrome, and atypical multiple sclerosis to name a few. Once you have received a firm diagnosis of late-onset Krabbe disease, the treatment options are focused on improving quality of life. With the late-onset form, often hematopoietic stem cell transplant (HSCT) is an option for patients; however, it will be vital to connect with an expert well trained in Krabbe disease and HSCT to fully understand the risks, benefits, and outcomes associated with the unique neurological impact of KD. It has been clinically and scientifically proven that the earlier one receives an HSCT in late-onset KD, the higher the likelihood of slowing the progression of the disease.
Ongoing Care of Late-Onset KD
Treating late-onset KD with HSCT does not resolve or completely eradicate the disease. It’s important for you to know that transplanted patients can encounter complications from the transplant such as organ damage, graft rejection, infertility, interstitial pneumonia in addition to permanent neurological difficulties related to the disease. Consequently, post-transplanted patients need to be closely monitored by a team of experts to manage all medical, physical, and psychological aspects to ensure the best chance for living a quality life.
Additional Guidance on Treatment and Care
- Work with healthcare providers who listen to you and are available for questions and discussions. You know your child best and KD requires someone who can navigate the complications of this disease.
- Consider establishing two medical teams: (1) a Krabbe disease team of experts from a world-renowned center knowledgeable in performing complex long-term testing and familiar with new developments in the treatment of KD plus; (2) a local care team dedicated in handling immediate needs, proficient in standards of care assessments, responsive to renewing medications, and collaborates seamlessly with the Krabbe disease team of experts.
- If something doesn’t seem right, speak up! Most healthcare providers want to have discussions about your concerns and priorities to prevent misunderstandings in the treatment of and clinical care for this rare disease.
References
- Escolar ML, Poe MD, Provenzale JM, Richards KC, Allison J, Wood S, et al. Transplantation of umbilical-cord blood in babies with infantile Krabbe’s disease. NEJM. 2005;352:2069–81.
- Krivit W, Shapiro EG, Peters C, Wagner JE, Cornu G, Kurtzberg J, Wenger DA, Kolodny EH, Vanier MT, Loes DJ, Dusenbery K, Lockman LA. Hematopoietic stem-cell transplantation in globoid-cell leukodystrophyThe leukodystrophies comprise a group of progressive, genetic disorders mainly affecting the central nervous system (CNS). Most leukodystophies result from a disruption of the growth of the myelin sh. N Engl J Med. 1998;338:1119–26.
- Kwon, J.M., Matern, D., Kurtzberg, J. et al. Orphanet J Rare Dis (2018) 13: 30. https://doi.org/10.1186/s13023-018-0766
- Wenger DA. Krabbe disease. GeneReviews. www.ncbi.nlm.nih.gov/books/NBK1238/ (Accessed on February 5, 2018).
- Wright MD, Poe MD, DeRenzo A, Haldal S, Escolar ML. Developmental outcomes of cord blood transplantation for Krabbe disease: a 15-year study. Neurology. 2017;89:1365–72.