Krabbe Disease in Babies

Krabbe disease, also known as globoid cell leukodystrophy, affects the central nervous system. The disease can strike people of all ages, although symptoms are generally much less severe in adults and older children. Some might only suffer from muscle weakness and not experience any cognitive impairments. Krabbe disease in babies presents a much more serious problem.

Significance

• According to the Mayo Clinic, about one in every 100,000 Americans develops Krabbe disease. Most of these cases occur in babies under six months of age. No cures exist for this often fatal disease. Most infants with Krabbe disease die before reaching the age of 2. The disease can progress rapidly in babies and lead to death due to respiratory failure or decreased muscle tone and immobility complications.

Symptoms

• Behavioral signs of early-onset Krabbe disease include unexplained crying and extreme irritability. Physical symptoms include seizures, loss of head control, muscle and limb stiffness, impaired movement, vomiting, fever and muscle spasms. Vision and hearing loss, as well as feeding difficulties, can also occur. Babies with Krabbe disease also do not reach developmental milestones. Respiratory problems and infections can develop in the later stages of the disease. Consult your baby's doctor immediately if you notice any of these symptoms, so a prompt diagnosis can be made.

Causes

• A genetic defect inherited from both parents causes Krabbe disease. A baby has a 25 percent chance of developing the disease when both parents are carriers. If only one parent carries the defective gene, a baby will also carry it, but won't develop symptoms. This defect leads to a deficiency in the galactocerebrosidase, or GALC, enzyme that maintains myelin, which insulates nerve fibers. A reduction in myelin results in neurological impairment. The loss of GALC leads to an increased number of galactolipid molecules, which reside in globoid cells in the brain. High levels of a galactolipid known as psychosine cause myelin production to slow down or stop as the cells that make this substance self-destruct.

Treatment

• With no cure available, treatments for Krabbe disease instead focus on relieving symptoms. Medications to reduce vomiting or seizures can be prescribed. Cord blood transfusions and blood marrow transplants might provide some relief for infants with the disease. Newborns diagnosed at birth could benefit from a hematopoietic stem cell transplant. This procedure replaces a baby's bone marrow with bone marrow from an adult. According to the Mayo Clinic, more research and long-term follow-ups are needed to evaluate this option. Transplants fail to provide benefits in older babies and fetuses with the disease. Small studies have shown that using a cord blood transfusion to introduce healthy blood stem cells with normal GALC activity into babies who haven't exhibited symptoms can reduce neurological symptoms. This procedure helps myelin develop regularly. Although hearing and vision remained normal in these babies, they did experience later impairment of motor skills and language expression. Gene therapy could be used in the future to replace the defective gene with a healthy one.

Screening

• Newborn screening for Krabbe disease can lead to early detection. When diagnosis occurs shortly after birth, stem cell transplants that might slow the onset of the disease can be performed in some cases. Early diagnosis also makes it possible to receive prompt and supportive care, which can improve quality of life. Prepregnancy screening, including genetic counseling, will also help you understand the risks involved with having a child if both you and your partner are carriers of the Krabbe disease gene.