Gastrointestinal Surgery and Wernicke Encephalopathy

Wernicke encephalopathy (WE) is a cause of rapidly progressive but reversible dementia due to deficit of thiamine (the B1 vitamin). In developed countries, WE is principally described in chronic alcoholism; however, it can also develop in other, probably underestimated and undiagnosed, nonalcoholic conditions. The nonalcoholic conditions causing reduced intake (malnutrition, reduced or absent absorption) or increased consumption of thiamine can be physiologic (aging) or pathologic. Abdominal surgery for cancer is an underestimated cause of atypical WE leading to high morbidity and mortality in which the diagnosis is often missed or delayed. Alongside acute neurological emergence, chronic deficit of thiamine may contribute to the neurodegenerative process leading to senile dementia and Alzheimer's disease. This chapter provides an overview of (1) the main metabolic effects of thiamine in specific brain areas; (2) the natural history of WE in patients who have undergone abdominal surgery for cancer; (3) the mechanisms linking thiamine deficiency to Alzheimer's disease; and (4) alternative causes of rapidly progressive dementias that should be differentiated from atypical WE.