Aicardi syndrome is a rare genetic disorder that interferes with the formation of the corpus collusum, the connector between two hemispheres of the brain.
Medical researchers do not believe that the disorder is passed down from parents to child. Scientists instead think it is caused by a first-time mutation in a child’s genetic code.
Scientists believe that Aicardi syndrome is caused by a defect in the X chromosome—and the condition appears most often in girls. It can also be present in boys with Klinefelter syndrome, a disorder where a male has an extra X chromosome.
During normal development of an embryo, there should only be one active X chromosome in each cell. This means that X chromosomes must randomly deactivate during cell formation. In the case of Aicardi syndrome, scientists theorize that these chromosomes do not alternate randomly as they should and one X chromosome takes part in more than half of the body’s cell formations. This is called skewed X-activation.
Scientists have yet to pinpoint the exact gene that causes skewed X-activation. Thus, the precise cause of the disorder is still not known. This lack of information makes it difficult to pinpoint the risk factors for Aicardi syndrome.
While a child born with Aicardi syndrome may appear normal at birth, symptoms of the disorder begin to appear usually between age 2 and 5 months. Your child may begin jerking or have infantile spasms, a type of seizure that occurs in infants. These seizures can develop into epilepsy later in life. Your child may also have yellowish spots on the eyes caused by lesions on the retina. Some other symptoms of Aicardi syndrome are:
- Coloboma, a congenital defect of the iris of the eye
- mental retardation
- eyes that are smaller than normal
- difficulty eating
- gastroesophageal reflux
Because Aicardi syndrome can result in poorly developed eyes, children with the disorder may also suffer from impaired vision or blindness. Irregularities in the ribs and spine like scoliosis are also possible signs of Aicardi syndrome. Children with the disorder may have hands and heads that are smaller than normal. They may also have skin problems and facial symmetry issues. This includes having a flatter nose, larger ears, or a smaller space between the upper lip and nose. Scientists have also found that the brains of children with Aicardi syndrome may also have fewer folds than a normal brain. Fluid filled cysts are also sometimes present in the brain.
Aicardi syndrome is most commonly diagnosed by its symptoms, but because each child may present different symptoms, additional tests may be needed. Some tests that are used are eye exams, electroencephalogram (EEG), and magnetic resonance imaging (MRI). CT scans of the head and brain are also important diagnostic tools because they allow a view into the brain’s condition.
Because Aicardi syndrome is a genetic disorder, there is no cure at this time. The most common method of treatment involves controlling the seizures and spasms brought on by the disease. There are also programs available to help both children and their parents cope with the mental retardation that usually accompanies Aicardi syndrome. It is likely that if your child has the disorder your doctor will recommend a pediatric neurologist to help with long-term management of the condition.
Those with Aicardi syndrome have a higher chance of dying during childhood and their prognosis greatly depends on the intensity of their symptoms. Nearly all children with the syndrome have some form of mild to severe mental retardation. Some children with Aicardi syndrome are able to speak and walk by themselves while others may need support to walk. They will likely be completely dependent and need a caretaker for the rest of their lives.