Canavan disease is an autosomal recessively inherited leukodystrophy characterized by white matter degeneration. The defective gene is the aspartoacylase gene that encodes the enzyme aspartoacylase. Head lag, macrocephaly, and hypotonia are the primary characteristic physical examination findings. A 6 month-old patient presented with developmental delay and normocephaly. Brain magnetic resonance imaging showed delayed myelinization at the corpus callosum, genu of the internal capsule, and posterior limb and hyperintensity of the globus pallidus, thalamus, dorsal aspect of the brain stem, corticospinal tract, and cerebellum. Magnetic resonance spectroscopy demonstrated a prominent N-acetyl aspartate peak, which is a typical pathological finding. Genetic testing revealed the presence of a homozygous c.79, G>A (p.G27R) mutation, which confirmed the diagnosis of Canavan disease. During follow-ups, the child was normocephalic, even at the 1 year visit.
Keywords: Canavan disease, normocephaly, magnetic resonance spectroscopy, genetic testing