A rare neurological disorder, Alexander disease primarily affects the central nervous system. In this disorder, myelin, which protects brain nerve fibers, is destroyed, resulting in the formation of abnormal deposits known as Rosenthal fibers. This condition is progressive and manifests in both children and adults. Here's a straightforward breakdown of the causes, symptoms, diagnosis, treatment, and prevention of Alexander disease.
Causes
In Alexander disease, the GFAP gene is mutated, which makes glial fibrillary acidic protein. A protein called glial fibrillary acidic protein is found primarily in astrocytes, brain support cells. As a result of mutations in the GFAP gene, Rosenthal fibers and myelin destruction occur, resulting in the abnormal accumulation of glial fibrillary acidic protein.
Symptoms
According to the age at which Alexander disease began and its severity, its symptoms can vary widely. Developmental delays, seizures, feeding difficulties, and an enlarged brain can be symptoms of macrocephaly in infants and young children. In older children and adults, problems with speech and swallowing, muscle stiffness, loss of motor function, and cognitive decline may occur.
Diagnosis
A combination of clinical evaluations, neuroimaging studies, and genetic tests is typically used to diagnose Alexander disease. It is possible to detect characteristic abnormalities of the brain through magnetic resonance imaging (MRI), such as white matter changes and Rosenthal fibers. GFAP mutations can be confirmed by genetic testing, providing a definitive diagnosis.
Treatment
Currently, Alexander disease has no cure, so treatment is focused on managing symptoms and improving quality of life. Physical therapy is used to address motor difficulties, speech therapy is used to improve communication skills, and medications are used to manage seizures and muscle stiffness. The pressure on the brain caused by fluid buildup may require surgery in some cases.
Prevention
Alexander disease is a genetic disorder caused by mutations in the GFAP gene, so there are no known ways to prevent it. Individuals with a family history of the condition, however, may benefit from genetic counseling. For couples undergoing in vitro fertilization, genetic counselors can provide information about the risk of passing on a mutated gene to future generations as well as discuss options such as preimplantation genetic diagnosis (PGD).
