Ataxia with Isolated Vitamin E Deficiency


Ataxia with vitamin E deficiency (AVED), or familial isolated vitamin E deficiency, is a rare form of autosomal recessive progressive ataxia with features similar to FRDA.  Although most commonly arising before 20 years of age, the age at onset ranges from 3 to 62 years.  Patients develop progressive gait unsteadiness and dysarthria that progresses to wheelchair confinement at a more variable (3-37 years) pace than that of Friedreich's ataxia.  Examination usually reveals dysarthria, hand incoordination, gait unsteadiness, arreflexia, and vibratory/proprioceptive sense loss.  More than 1/2 patients have extensor plantar responses.  Diffuse muscle weakness most prominent distally may be present in 42% of patients.  Retinopathy (9%) or dystonia/bradykinesia (13%) are found in minority of patients. Cardiomyopathy is also found in about 19% of patients.  Skin may show xanthelasmata or tendon xanthomas.

The diagnosis of AVED is made by determination of serum vitamin E (alpha tocopherol) levels, which are severely reduced or totally absent,  or by DNA testing.  Treatment consists of supplementation with oral doses of vitamin E at a dose of 800 mg twice daily, along with supportive care.