[Vitamin E deficiency. Etiopathogenesis, clinical, histopathologic, and electrical features, and main etiologies].

Vitamin E deficiency is frequently observed in human pathology. In most cases, deficiency is moderate and asymptomatic. Severe deficiency is rare and presents as a progressive neurological syndrome including cerebellar ataxia and posterior cord injury. Neuropathological and electrophysiological features confirm spinocerebellar degeneration. The pathophysiology of vitamin E deficiency nervous dysfunction is still unknown. Oxidative alterations due to the lack of the main lipid-soluble antioxidant could be involved. A few causes of vitamin E deficiency are recognized (malnutrition, impaired lipid absorption, specific anomaly of hepatic or intestinal secretion of vitamin E, excessive endogenous consumption), but diseases associated with vitamin E deficiency are numerous and divers. Symptomatic severe deficiency is constantly observed in ataxia with vitamin E deficiency and abetalipoproteinemia. Intestinal, hepatobiliary, and pancreatic diseases are often associated with more or less marked deficiency. Other pathological circumstances such as malnutrition, alcoholism, hemolytic anemia, renal failure and hemodialysis could be associated with moderated and asymptomatic vitamin E deficiency. Oral or regular administration of high-dose vitamin E is required for patients with symptomatic severe deficiency. An adapted supplementation is recommended for patients with a marginal vitamin E status.