Wernicke's encephalopathy
SUMMARY AND RECOMMENDATIONS — Wernicke's encephalopathy (WE) and Korsakoff's amnestic syndrome (KS) are, respectively, acute and chronic brain disorders that result from thiamine deficiency.
WE is most often associated with alcoholism but can also occur in other situations including malnutrition from any cause (particularly at the time of refeeding) and in dialysis patients. (See 'Associated conditions' above.)
WE produces petechial hemorrhagic necrosis in midline brain structures and corresponding deficits in mentation, oculomotor function, and gait ataxia. All three of these classic symptoms are present in only one-third of patients. Any one of these, but most often encephalopathy, may be seen in isolation. WE should be considered when one or more occur. (See 'Clinical manifestations' above.)
While laboratory measurements and neuroimaging are often abnormal in WE, there is no single test with sufficiently high diagnostic accuracy. The first imperative is to administer thiamine rather than confirm the diagnosis, whenever WE is considered. (See 'Diagnosis' above.)
Untreated, WE leads to coma and death. Prognosis is improved by prompt administration of thiamine. Immediate, parenteral administration of thiamine is required whenever the diagnosis of WE is entertained. A suggested treatment regimen is 500 mg intravenous (IV), infused over 30 minutes, repeated three times daily for two consecutive days and 500 mg IV or IM once daily for an additional five days. Oral thiamine and multivitamin supplementation are recommended thereafter as long as the patient remains at risk. (See 'Clinical course and prognosis' above.)
Wernicke's encephalopathy may be precipitated by administration of intravenous glucose solutions to individuals with thiamine deficiency. In susceptible individuals glucose administration should be preceded or accompanied by thiamine 100 mg IV (Grade 1A). (See 'Prevention' above.)
Thiamine supplementation, along with other multivitamin supplementation, is recommended for patients at risk for thiamine deficiency. (See 'Prevention' above.)