Krabbe's disease is a rare disorder; it happens only once out of every 100,000 births. But it is also a fatal disease. The Centers for Disease Control and Prevention started a program in 2005 called the Newborn Screening Translation Research Initiative. One of the goals of the initiative is to establish screening tests for all newborns that will include screening for Krabbe's.
What Causes It?
Krabbe's disease is a hereditary disease. Children born with this disorder do not have enough of an enzyme called galactocerebroside beta-galactosidase. This enzyme is needed to break down a substance called galactocerebroside, which is an important part of brain nerve tissue. According to Allan Ropper, M.D., professor of neurology at Harvard Medical School, in "Adams & Victor's Principles of Neurology," if galactocerebroside accumulates, it destroys the oligodendrocytes, cells that are needed so that the nerve cells of the brain and spinal cord can quickly send signals.
Early Symptoms
Ramzi Cotran, M.D., professor of pathology at Harvard Medical School, writes in "Robbins Pathologic Basis of Disease" that infants will start having symptoms when they are only three to six months old. They become stiff all over their body, may have spasms, and develop an abnormal curvature in their neck and upper body. They will usually start to have problems eating and tend to vomit frequently. The infants may also cry a lot of the time and become irritable and less alert.
Later Symptoms
In "Adams & Victor's Principles of Neurology," Dr. Ropper explains that as the disease progresses, infants may keep their arms bent at the elbow with their fists clenched and their legs sticking straight out. They then develop problems with their reflexes, and become deaf as well as blind. Most children die by the time they are one year old. Neurologists consider it rare for a child with Krabbe's disease to be older than two years old.
Diagnosis
Infants suspected of having Krabbe's disease are given an electroencephalograph (EEG), which records the electrical signals of the brain. An infant or child with Krabbe's disease will show slow signals. As the disease develops, a CT or an MRI will show that more of the brain is being affected. An electromyograph (EMG), which records the electrical activity of the muscles, will show that the nerves of an infant or child with Krabbe's disease are being damaged, and that the signals from the nerves are being transmitted more slowly than normal.
Treatment
Krabbe's disease is a fatal disease; there is no cure. But in the May 19, 2005 issue of "The New England Journal of Medicine," Maria Escolar, M.D., wrote that researchers transplanted blood cells from umbilical cords to 11 infants with Krabbe's before they showed any symptoms. Blood cells were also transplanted to 14 infants who had symptoms. Three years later, most of the 11 asymptomatic infants still showed few symptoms, and most had average scores when tested on their behavior, on their ability to solve problems, and their ability to understand and express their needs.
References
- "Adams & Victor's Principles of Neurology"; Allan Ropper, M.D. and Martin Samuels, M.D.; 2009
- Centers for Disease Control and Prevention: Newborn Screening Laboratory Bulletin
- "Robbins Pathologic Basis of Disease"; Ramzi Cotran, M.D., Vinay Kumar, M.D., and Stanley Robbins, M.D.; 1994
- "New England Journal of Medicine"; Transplantation of Umbilical-Cord Blood in Krabbe's Disease; 2005
