Abstract
Wernicke's encephalopathy is an acute neuropsychiatric syndrome resulting from vitamin B_1 (thiamin) deficiency. Criteria for diagnosing Wernicke's encephalopathy requires the presence of three clinical signs, i.e., oculomotor abnormalities, cerebellar dysfunction, and confusion. However, it has often been reported that most patients do not fulfill all of the three criteria. Autopsy-based studies indicate that the disorder is still underdiagnosed. Even diagnosing the disorder, an insufficient treatment is followed by mental sequelae such as Korsakoff syndrome. The guideline of treatment of Wernicke's encephalopathy has not been established in Japan. Patients with Wernicke's encephalopathy should be treated empirically with a minimum of 500 mg thiamin (dissolved in 100 ml of physiological saline) for 2〜3 days. In this treatment, thiamin is infused to the patients over a period of 30 min three times per day. In a case of no response, thiamin supplementation should be discontinued after a few days. Other vitamins including vitamin B_2, vitamin B_6, nicotinamide, and vitamin C should be additionally given to the patients, because multivitamin could be deficient in the patients. The clinical manifestations in the patients may be iatrogenically precipitated by glucose loading. To avoid this complication, thiamin must be administered prior to glucose loading.
