[Wernicke encephalopathy in patients given parenteral nutrition].

Wernicke's encephalopathy is caused by thiamin deficiency and can be recognized by severe neurological symptoms that are occasionally accompanied by systemic signs. The syndrome is often found in alcoholics, although other causes have also been identified, such as intravenous feeding, in which the main pathogenic mechanisms are the administration of carbohydrates and the low standard dose of vitamin B1--in relation to the increase in metabolic load--delivered in a medium of substances that favor inactivation of the vitamin. We present 3 intravenously fed patients who developed the syndrome, even though in 2 cases they were given thiamin. Only the third patient's history included chronic alcoholism, and this patient also suffered severe cardiac symptoms and amaurosis. We believe that the amount of thiamin provided through parenteral nutrition, as well as the medium in which it is delivered, must be reviewed.