Wernicke—Korsakoff syndrome

Thiamin has a very low toxicity (oral LD5o of thiaminchloride hydrochloride in mice 3-15 g/kg body weight). The vitamin is used therapeutically to cure polyneuropathy, beri-beii (clinically manifest thiamin deficiency), and Wernicke-Korsakoff Syndrome ( Wernicke encephalopathy and Korsakoff psychosis). In mild polyneuropathy, 10-20 mg/d water-soluble or 5-10 mg/d lipid-soluble thiamin are given orally. In more severe cases, 20-50 mg/d water-soluble or 10-20 mg/d lipid-soluble thiamin are administered orally. Patients suffering from beri-beri or from early stages of Wernicke-Korsakoff Syndrome receive 50-100 mg of thiamin two times a day for several days subcutaneously or intravenously until symptoms are alleviated. Afterwards, the vitamin is administered orally for several weeks. 

Friedman], Westlake R, Furman M Grievous bodily harm gamma hydroxybutyrate abuse leading to Wernicke-Korsakoff syndrome. Neurology 46 469 71, 1996 Gallimberti L, Ferri M, Ferrara SD, et al Gamma-hydroxybutyric acid in the treatment of alcohol dependence a double-blind study. Alcohol Clin Exp Res 16 673-676, 1992... 

B, Thiamin Coenzyme in pyruvate and a-ketoglutarate, dehydrogenases, and transketolase poorly defined function in nerve conduction Peripheral nerve damage (beriberi) or central nervous system lesions (Wernicke-Korsakoff syndrome)... 

The Wernicke-Korsakoff syndrome follows years of chronic alcohol abuse. However, alcoholics who do not develop this condition typically display a range of other cognitive impairments (Grant et al., 1987). Deficits in performance have been... 

Thiamine deficiency results in early decreases in activity of the mitochondrial enzyme a-ketoglutarate dehydrogenase in brain. Wernicke s encephalopathy, also known as the Wernicke-Korsakoff syndrome is a neuropsychiatric disorder characterized by ophthalmoplegia, ataxia and memory loss. Wernicke s encephalopathy is encountered in chronic alcoholism, in patients with HIV-AIDS and in other disorders associated with grossly impaired nutritional status. The condition results from thiamine deficiency. 

Amnesia. Like dementia, the main feature of amnesia is memory loss. Amnesia, however, does not affect other intellectual abilities in the same manner as dementia. Distingnishing dementia from amnesia is most often a consideration when you evaluate memory problems in a chronic alcoholic. Alcoholics may become demented, but they may also develop an amnestic disorder known as Wernicke-Korsakoff syndrome. 

In chronic alcoholics, thiamine deficiency may manifest as Wernicke-Korsakoff syndrome, which Is characterized by a constellation of unusual neurologic disturbances. Including amnesia, apathy, and nystagmus. 

Wernicke-Korsakoff syndrome is a relatively uncommon but important entity characterized by paralysis of the external eye muscles, ataxia, and a confused state that can progress to coma and death. It is associated with thiamin deficiency but is rarely seen in the absence of alcoholism. Because of the importance of thiamine in this pathologic condition and the absence of toxicity associated with thiamine administration, all patients suspected of having Wernicke-Korsakoff syndrome (including virtually all patients who present to the emergency department with altered consciousness, seizures, or both) should receive thiamine therapy. Often, the ocular signs, ataxia, and confusion improve promptly upon administration of thiamine. However, most patients are left with a chronic disabling memory disorder known as Korsakoff s psychosis. 

Thiamine (vitamin B1 ) Essential vitamin required for synthesis of the coenzyme thiamine pyrophosphate Administered to patients suspected of having alcoholism (those exhibiting acute alcohol intoxication or alcohol withdrawal syndrome) to prevent Wernicke-Korsakoff syndrome Administered parenterally Toxicity None Interactions None... 

Wernicke-Korsakoff Syndrome Is Exacerbated by a Defect in Transketolase... 

In humans with Wernicke-Korsakoff syndrome, a mutation in the gene for transketolase results in... 

A genetic defect in transketolase that lowers its affinity for TPP exacerbates the Wernicke-Korsakoff syndrome. 

Wernicke-Korsakoff syndrome In the United States, thiamine defi-... 

Beriberi Wernicke-Korsakoff syndrome (most common in alcoholics) Tachycardia, vomiting, convulsions Apathy, loss of memory, eye movements None ... 

Vitamin B1 (thiamine) has the active form, thiamine pyrophosphate. It is a cofactor of enzymes catalyzing the conversion of pyruvate to acetyl CoA, a-ketoglutarate to succinyl CoA, and the transketolase reactions in the pentose phosphate pathway. A deficiency of thiamine causes beriberi, with symptoms of tachycardia, vomiting, and convulsions. In Wernicke-Korsakoff syndrome (most common in alcoholics), individuals suffer from apa thy, loss of memory, and eye movements. There is no known toxicity for this vitamin. 

Wernicke-Korsakoff syndrome, stemming from thiamine deficiency and characterized by confusion, ataxia, and ocular abnormalities (nystagmus and lateral rectus muscle palsy). 

Cochrane M, Cochrane A, Jauhar P, Ashton E. Acetylcholinesterase inhibitors for the treatment of Wernicke-Korsakoff syndrome - three further cases show response to donapezil. Alcohol Alcohol 2005 40 151-4. 

In general, a relatively acute deficiency is involved in the central nervous system lesions of the Wernicke-Korsakoff syndrome, and a high-energy intake, as in alcoholics, is also a predisposing factor. Dry beriberi is associated with a more prolonged, and presumably less severe, deficiency, with a generally low food intake, whereas higher carbohydrate intake and physical activity predispose to wet beriberi. 

Studies in thiamin-deficient animals revealed the presence of Alzheimer-like amyloid plaques in the brain. Although there is no evidence of similar plaque formation in the brains of patients with the Wernicke-Korsakoff syndrome, this has led to trials of thiamin for treatment of Alzheimer s disease... 

Zubaran C, Fernandes JG, and Rodnight R (1997) Wernicke-Korsakoff syndrome. Postgraduate Medical Journal 73, 27-31. 

Blass JP and Gibson GE (1977) Abnormality of a thiamine-requiring enzyme in patients with Wernicke-Korsakoff syndrome. New England Journal of Medicine 297, 1367-70. 

Ma JJ and Truswell AS (1995) Wernicke-Korsakoff syndrome in Sydney hospitals before and after thiamine enrichment of flour. Medical Journal of Australia 163, 531-4. 

Nixon PF, Kaczmarek MJ, Tate J, Kerr RA, and Price J (1984) An erythrocyte transketo-lase isoenzyme pattern associated with the Wernicke-Korsakoff syndrome. European Journal of Clinical Investigation 14, 278-81. 

Wang JJ, Martin PR, and Singleton CK (1997) A transketolase assembly defect in a Wernicke-Korsakoff syndrome patient. Alcohol Clinical and Experimental Research 21, 576-80. 

Keywords Vitamins Thiamine Wernicke-Korsakoff syndrome Pyridoxine Niacin Folic acid Antioxidants... 

Although now largely eradicated, beriberi remains a problem in some parts of the world among people whose diet is especially high in carbohydrates. A different condition, affecting the central rather than peripheral nervous system, the Wernicke-Korsakoff syndrome, is also due to thiamin deficiency. It occurs in developed countries, especially among alcoholics and narcotic addicts. 

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