Ataxia with vitamin E deficiency

AVED may be suspected in individuals who have the following findings at the beginning of puberty:

• Progressive ataxia
• Clumsiness of the hands
• Loss of the ability to know where one's body is in space (proprioception)
• Absent reflexes (areflexia)
• The inability to perform rapid, alternating movements (dysdiadochokinesia)
• A tendency to sway or fall while standing upright with the feet together, arms stretched out and the eyes closed (positive Romberg sign)
• A nodding movement of the head (titubation)
• Decreased visual sharpness (acuity)
• Positive Babinski sign (upward movement of the big toe and fanning of the feet after the sole of the foot has been firmly stroked)
• Macular atrophy (wasting away of the cells that form the part of our eye responsible for central vision)
• Retinitis pigmentosa (eye disease in which there is damage to the retina)

Laboratory studies typically show a reduced plasma vitamin E concentration but normal levels of lipoproteins (proteins that combine with and transport fat or other lipids in the blood). Other studies that may be useful include: nerve conduction studies, brain imaging, and studies of nerve tissues.

Although no universal diagnostic guidelines are available, researchers suggest that diseases that cause fat malabsorption, such as abetalipoproteinemia should be ruled out. Genetic testing finding two _TTPA _gene mutations may be useful to confirm the diagnosis.

Treatment for AVED requires lifelong high dose supplementation of vitamin E. When treated early, some symptoms, such as ataxia and intellectual decline, can be reversed. In older patients, treatment may slow disease progression, but some symptoms remain.

Research indicates that if vitamin E treatment is initiated in presymptomatic individuals with two mutations in the TTPA gene (e.g., younger sibs of an affected individual), the symptoms of AVED will not develop.