- Children deficient in vitamin E have various neurologic symptoms. 2 cases representing different mechanisms of this vitamin deficiency are reported. A 15-year-old boy with fat malabsorption due to cystic fibrosis who was diagnosed as being vitamin E deficient (< 0.5 mg/l), had typical neuropathies. On the other hand, a 12-year-old Beduin girl had isolated vitamin E deficiency, as well as neurological symptoms suggestive of Friedrich's ataxia. Vitamin E supplementation by intramuscular injection in the first case and per os in the second led to significant improvement in neurological symptoms.