Complete Information on Alexander disease with Treatment and Prevention

Alexander disease is a set of genetic conditions called the leukodystrophies that affect development of the myelin sheath, the fatty covering, which acts as an insulator-on nerve fibers in the brain. Alexander disease is considered an autosomal dominant disorder, which means one copy of the altered gene in each cell is sufficient to cause the disease. Almost all cases result from new mutations in the gene and occur in people with no history of the disorder in their family. Children with hydrocephalus caused by Alexander disease usually have increased intracranial pressure and a more rapid progression of the disease. Generally, the earlier the age of onset of Alexander disease, the more severe and rapid the course. Therefore, unaffected parents of a child with ALX are at a low risk to have another affected child.

Signs and symptoms of the infantile form typically include an enlarged brain and head, seizures, stiffness in the arms and legs, mental retardation, and delayed physical development. Less frequently, onset occurs later in childhood (the juvenile form) or adulthood. Common problems in juvenile and adult forms of Alexander disease include speech abnormalities, swallowing difficulties, and poor coordination. Infantile Alexander Disease leads to symptoms in the first two years of life; while some children die in the first year of life, a larger number live to be 5-10 years old. Alexander disease belongs to leukodystrophies, a group of diseases which affect growth or development of the myelin sheath. In Alexander disease, the growth of the white matter of the brain, or myelin sheath, is affected.

Cerebellar disease also occurs in this disorder. In most cases, Alexander disease appears to occur randomly for unknown reasons, with no family history of the disease. In an extremely small number of cases, it is thought that the disorder may have affected more than one family member. Affected children survive a few weeks to several years. The juvenile form usually presents between four and ten years of age, occasionally in the mid-teens. Survival is variable, ranging from the early teens to the 20s-30s. Prior to the identification of the genetic features, other names were used to describe the clinical features and pathology of Alexander disease, such as hyaline panneuropathy and dysmyelinogenic leukodystrophy. These terms are no longer used.

Because the genetic defect in Alexander disease is known, genetic testing on a blood sample can be used to diagnose most cases of Alexander disease. There is no medication for Alexander disease. Treatment, which is symptomatic and supportive, primarily consists of attention to general care and nutritional needs, antibiotic therapy for infections, and management of associated complications such as anti-epileptic drug therapy for seizures. A suggestive diagnosis can also be made from the clinical symptoms, including enlarged head size, combined with radiological studies and negative tests for other leukodystrophies. Surgical interventions, including placement of a feeding tube and/or shunting for hydrocephalus, may also be required. Orthopedic surgery for scoliosis has been reported in a case of Alexander disease.