Neuroacanthocytosis

Also known as choreoacanthocytosis, this neurodegenerative disorder is usually inherited as an autosomal recessive trait. Symptoms typically become apparent between the ages of 25 to 45 years. The disorder may be characterized by dystonia; chorea; tics, including lip "smacking" and "hissing" vocalizations; personality changes and cognitive decline; seizures; parkinsonism; and/or atrophy of muscle tissue (amyotrophy) with an abnormally high length-wise arch of the foot (pes cavus). The dystonia may affect muscles of the face, mouth, and tongue and may often be provoked by eating (i.e., action dystonia), leading to potentially mutilating lip- and tongue-biting.

Neuroacanthocytosis is associated with atrophy and neuronal loss within substructures of the basal ganglia, including the caudate nuclei and putamen (collectively known as the striatum) and the globus pallidus. There may also be neurodegenerative changes within the thalamus and certain regions of the spinal cord (i.e., anterior horns). The disorder may be confirmed by blood tests indicating that over 15 percent of red blood cells are acanthocytes or abnormal circulating red blood cells that have spur-like or thorny projections (i.e., acanthocytosis).

	Rett Syndrome