Thiamin deficiency: neurological, cardiac, and metabolic effects
THE CONTEXT
Thiamin deficiency produces three distinct clinical syndromes and can impair pyruvate metabolism.
Clinical syndromes
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Chronic beriberi presents as peripheral neuritis and may or may not be accompanied by heart failure and edema.
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Acute pernicious or fulminating beriberi, called Shoshin beriberi, predominantly causes heart failure and metabolic abnormalities without peripheral neuritis.
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Wernicke encephalopathy with Korsakoff psychosis is especially associated with alcohol and narcotic abuse.
Metabolic consequences
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Thiamin diphosphate participates in pyruvate dehydrogenase function; deficiency impairs conversion of pyruvate to acetyl-CoA.
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In individuals consuming a relatively high carbohydrate diet, deficiency increases plasma lactate and pyruvate concentrations and may cause life-threatening lactic acidosis.