Lactic acidosis caused by thiamine deficiency in a pregnant alcoholic patient

Background: Metabolic acidosis from accumulation of lactic acid is a relati vely common condition, whereas its causation by thiamine deficiency is not. Methods: We studied a pregnant alcoholic patient who presented with hyperem esis and a high anion gap acidosis. Results: Lactic acidosis and thiamine deficiency were confirmed. The patien t's symptoms and acidosis resolved with thiamine administration. Conclusions: Lactic acidosis caused by thiamine deficiency must be suspecte d when pregnant patients at risk for thiamine deficiency present with a hig h anion gap acidosis. A large dose of thiamine must be administered immedia tely.