Wernicke's encephalopathy: An underrecognized and reversible cause of confusional state in cancer patients

Background: Wernicke's encephalopathy (WE) is a neurological emergency which presents with symptoms of confusion, ophthalmoplegia, and ataxia. Cancer patients are at high risk of this acute encephalopathy due to chronic malnutrition, chemotherapy-induced nausea and vomiting, and consumption of thiamine by rapidly growing tumors. A high index of suspicion is important as these critically ill patients may not present with the classic triad of symptoms. Methods: This study is a retrospective review of 5 patients with WE identified at M.D. Anderson Cancer Center, Houston, Tex., USA. Detailed clinical histories, risk factors, imaging, and histopathological characteristics are described. Results: Five WE patients were identified and all patients had rapidly growing cancers and were undergoing active treatment. All patients had poor nutritional status due to chronic nausea from chemotherapy. Three patients received bone marrow transplantation (BMT). Acute confusion was the most common symptom. Magnetic resonance imaging studies of the brain revealed restricted diffusion and fluid attenuation inversion recovery sequence hyperintensity in the medial thalami and periaqueductal gray matter. In 2 cases, WE was considered antemortem, and only 1 was empirically treated with thiamine, which rapidly reversed the imaging findings within 7 days and led to clinical improvement. Other cases were diagnosed at autopsy. Conclusion: It is crucial to consider WE in the differential diagnosis for all cancer patients with confusion. Cancer patients with malnutrition and patients with BMT are at high risk of developing WE. To prevent this devastating and often fatal neurologic complication, all cancer patients with confusion should be empirically treated with thiamine.