Snapshot A 44-year-old male presents with confusion and gait instability. Medical history is significant for alcohol use disorder, requiring multiple hospitalizations for alcohol intoxication. He drinks one to two pints of vodka daily. On exam, he appears inattentive, has bilateral horizontal nystagmus, and his gait is slow and wide-based. Introduction Wernicke-Korsakoff (WK) syndrome secondary to thiamine (B1) deficiency bilateral necrosis of the mammillary bodies dorsal medial nucleus of the thalamus is also involved triad: confusion (encephalopathy), ataxia, ophthalmoplegia complete triad not always present occurs in ~30% of cases cannot rule out WK on absence of triad Pathophsiology certain metabolic enzymes use thiamine as a cofactor e.g., pyruvate dehydrogenase, transketolase, alpha-ketoglutarate dehydrogenase increased thiamine demand when metabolic demand is increased or increased glucose intake must give thiamine before glucose administration seen in chronic alcoholism, and other conditions of poor nutritions (e.g., malabsorption) Epidemiology alcoholics are mostly affected Presentation Symptoms Wernicke's encephalopathy confusion opthalmoplegia ataxia Korsakoff's psychosis memory loss confabulation hallucination personality change Evaluation Clinical diagnosis primarily Thiamine level low non-specific Erythrocyte thiamine transketolase can establish thiamine deficiency Differential Alcohol intoxication Early Alzheimer's disease Treatment Intravenous thiamine administer immediately leads to improvement of reversible symptoms Prognosis, Prevention, and Complications Prevention adeqaute thiamine intake Complications lead to Korsakoff syndrome if Wernicke's encephalopathy is not treated