Canavan's Disease and Alexander's Disease

• Degenerative developmental disease of the White Matter
• present in infancy with progressively enlarging head and regression
• brain biopsy is needed for diagnosis
• both are autosomal recessive
• deficiency in asparto acylase, leading to N-acetyl aspartic acid accumulation
• shows spongy degeneration in Canavan's; shows Rosenthal fibers in Alexander's