Objective: Thiamine-related encephalopathy (Wernicke's encephalopathy) is a neuropsychiatric syndrome caused by a vitamin B1 (thiamine) deficiency often associated with alcoholism. Cancer predisposes patients to thiamine deficiency unrelated to alcoholism, though many cases are missed clinically. The present report adds to the literature on thiamine as a palliative tool for thiamine-related encephalopathy (TRE) in cancer.
Method: From a larger series of TRE in cancer, we report on three cases with terminal illness.
Results: Case 1. A 61-year old woman with Hodgkin's lymphoma developed TRE over 13 days. Precipitants included a hypermetabolic state in the background of subacute thiamine deficiency. Diagnosis was supported by abnormal serum thiamine and positive MRI findings. Mental status improved within 36 hours of initiating thiamine 500 mg IV t.i.d. Case 2. A 68-year-old man with colon cancer metastatic to liver and bone developed TRE precipitated by C. difficile-related diarrhea superimposed on 3 months of low appetite and weight loss. Diagnosis was supported by abnormal serum thiamine, and thiamine 500 mg IV t.i.d. was initiated. Improvements in mental status began within 36 hours. Case 3. An 80-year-old man with squamous cell carcinoma developed TRE precipitated by systemic infection in the context of three weeks of dysphagia. Antibiotic treatment did not reverse his cognitive symptoms, and a diagnosis of TRE was made based on operationalized criteria. Thiamine 100 mg IV daily did not reverse his symptoms. On his 30th day of admission, thiamine was increased to 500 mg IV t.i.d., resulting in a rapid reversal of altered mental status.
Significance of results: This report adds to the list of cancer types in which TRE/Wernicke's encephalopathy has been reported. It supports the use of higher doses of thiamine than are typically recommended in North America. Improvement following treatment allowed patients to engage with family and treatment teams prior to death.
Keywords: Cancer; Delirium; Thiamine; Thiamine-related encephalopathy; Wernicke's encephalopathy.