The answer to the simple question, “What is Canavan Disease?” is a bit complex. Canavan disease is a neurological birth disorder that affects infants. Canavan disease and other genetic disorders related to this condition are collectively known as Leukodystrophies.
Canavan disease is a common cerebral degenerative disease that causes progressive brain atrophy. Basically, this disease is characterized by degeneration of the white matter of the brain.
The white matter consists of nerve fibers that are covered by a fatty substance called myelin sheath that acts as an insulator. In Canavan disease, the normal growth and development of this myelin sheath is affected adversely due to genetic mutation.
Consequently, the nerve fibers are rendered unprotected and eventually die out thereby causing serious brain damage. This disease is more prevalent among Ashkenazi Jews from eastern Poland, Lithuania and western Russia.
The risk of developing this fatal disease increases when both the parents of an individual carry this genetic mutation. In such cases, the newborn child tends to have a 25 % probability of developing this inherited disorder even if the parents do not have any symptoms of the disease.
A simple parental blood test can help identify this disease. Degeneration of white matter in the brain can be diagnosed through CT scans and MRIs. Genetic testing for gene mutation also helps to determine the presence of Canavan disease.
Signs and Symptoms of Canavan Disease
Some common signs and symptoms of Canavan disease are abnormally large head (Macrocephaly), abnormally floppy or stiff muscle tone, loss of previously acquired motor skills, mental retardation, severe feeding difficulties, blindness, hearing loss, paralysis and various other symptoms.
The affected individuals, in this case, children tend to become quiet, lethargic and apathetic. The symptoms usually start manifesting by the age of 3-9 months.
Such children tend to develop developmental problems and problems related to the motor skills like difficulty controlling head movements, abnormal postures, muscle weakness etc.
Later on, symptoms like seizures, sleep disturbances, intellectual disability and other related symptoms also develop.
There is no known cure for this fatal disease characterized by an autosomal recessive pattern. The currently used treatments aim at reducing the symptoms of this disease. As a result, most of the affected infants usually succumb to death by the age of 4. Though, some may live up to their teens or twenties.