Globoid Cell Leukodystrophy (GLD)/Krabbe Disease
GLD is a rare genetic disorder where the enzyme galactocerebrosidase (GALC) is missing. This results in a build up of globoid cells in the brain tissue. Normally, nerve endings are covered with a myelin sheath which helps speed the communication of nerve impulses. In GLD, the myelia breaks down, affecting the patient's development. As the disease progresses, the patient rapidly deteriorates.
Classic Krabbe Disease manifests itself in infants between three and six months old. The child will develop normally until the onset of the disease, at which point parents will first begin to notice the child is extremely irritable. "The bounds of the crankiness cannot fully be explained unless you have experienced it...Our son cried for three days straight at one point and was hoarse for a week after," stated one parent. Other initial symptoms may include frequent fevers, difficulty keeping food down, stiffness in the limbs, and frequent seizures. Eventually the child will become blind and paralyzed. Most infants do not survive past the age of two. There are two additional forms of the disease with slower rates of progression which are referred to as the juvenile and adult forms. The juvenile form typically manifests itself after the 2nd birthday. The onset of juvenile GLD is between 3 and 10 years with a duration of greater than 5 years. The disease is typically characterized by decline in intelligence and motor skills, loss of vision, and difficulty walking. The adult form has its onset in the teenage or adult years, often between 10 and 35 years of age. It typically includes decreasing intelligence, neurological abnormalities, and loss of vision.
Because GLD is genetic, it is difficult to cure. Current approaches to GLD include genetic counseling for parents who are carriers of the disease. Early detection of the disease in unborn children may allow very early intervention, which can provide the best chance for helping these children. For GLD patients, a variety of treatments have been tried. The goal of treatment is to get the missing GALC enzyme into the body. Unfortunately directly injecting it into the bloodstream has proven unsuccessful, since the enzyme cannot make it from there to the brain.
Bone marrow or cord blood transplants are used to replace in the body bone marrow cells with the ability to make galactocerebrosidase. These marrow cells are able to travel to the brain. BMT can halt the progression of GLD if it has not progressed too far, but it cannot repair the existing damage. Therefore, BMT is recommended for patients with disease in very early stages or who have a slower progressing form of GLD. It is possible that immediate BMT after birth may help children with the infantile form of this disease. For other patients, doctors treat the symptoms of the disease, using seizure control medication, physical therapy, and antibiotics to help the child become more healthy and comfortable.
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