This form of leukodystrophy causes the white matter of the brain to be replaced by microscopic fluid filled spaces, and is characterised by structural abnormalities and the deterioration of motor, sensory, and intellectual functions. Curiously, this form seems to affect persons of Eastern European Jewish ancestry most frequently. Feeding difficulties are often the first symptom, followed by progressive mental retardation and apathy. The brain swells, causing the head to progressively enlarge as the bones of the skull fail to fuse normally. Vision and sometimes hearing may deteriorate due to nerve degeneration, and spasticity and paralysis develop.
Mental deterioration progresses with time.
The brain itself is enlarged. Cyst-like spaces pervade the white matter, with large quantities of fluid accumulating in the membranes covering the brain. Pneumonia may develop due to depressed chest movement while breathing. Canavan disease can affect both boys and girls, and is inherited through an autosomal recessive mechanism. Excessive amounts of N-acetylaspartic acid in body fluids appear in biochemical testing, as does deficiency of the enzyme aspartoacylase.