Wernicke's encephalopathy complicating schizophrenia.

Wernicke's encephalopathy producing an altered mental state may occur in malnourished psychiatric patients even in the absence of alcohol abuse. A case is reported of a woman, aged 61 years, with schizophrenia who refused her medication for four months, had the delusion she was dying from a tumour, and withdrew to her bed with a neglect of her nutrition. She was committed to hospital in a mute unresponsive state and after taking some food and fluids for four days lapsed into coma. She responded within three hours to the administration of thiamine. Clinicians need to remain vigilant to the possibility that an altered mental state in malnourished patients may be due to thiamine deficiency rather than to the primary psychiatric disorder. If doubt exists as to the presence of Wernicke's encephalopathy, then parenteral thiamine should be administered.