Caused by the acute deficiency of thiamine in a susceptible host.
Under-diagnosed in clinical practice.
The spectrum of patients affected continues to increase with changing medical practice.
The neuropsychiatric manifestations are varied but typically include alterations of consciousness, eye movement abnormalities, and gait and balance disorders.
Unless treated as an emergency with thiamine replacement parenterally, permanent neurological injury may occur.
Wernicke's encephalopathy is a neurological emergency resulting from thiamine deficiency with varied neurocognitive manifestations, typically involving mental status changes and gait and oculomotor dysfunction.
History and exam
Key diagnostic factors
- history of GI surgery
- mental slowing, impaired concentration, and apathy
- frank confusion
- ocular motor findings
- mental status changes, ophthalmoplegia, and gait dysfunction
Other diagnostic factors
- alcohol dependence
- pre-existing conditions that predispose to malnutrition: for example, AIDS, cancer, prolonged vomiting, or diarrhoea
- mild irritability
- acute psychosis
- miosis, anisocoria, light-near dissociation
- papilloedema, retinal haemorrhages
- tachycardia or hypotension
- hypothermia or hyperthermia
- hearing loss, seizures, and spastic paraparesis
- alcohol dependence
- cancer and treatment with chemotherapeutic agents
- history of gastrointestinal surgery
- bone marrow transplantation
- infants who have been fed formula milk deficient in thiamine
- male sex
1st investigations to order
- therapeutic trial of parenteral thiamine
- finger-prick glucose
- serum electrolytes
- renal function
- urinary and serum drug screen
- serum ammonia
- blood alcohol level
- blood thiamine and its metabolites
- serum magnesium
Investigations to consider
- lumbar puncture
- MRI of brain
- CT of brain
moderate or high suspicion of Wernicke's encephalopathy
low suspicion of Wernicke's encephalopathy or mimics: at high risk for Wernicke's encephalopathy
poor dietary intake and/or chronic alcoholism: at risk for Wernicke encephalopathy
Abhay Moghekar, MB BS
Department of Neurology
Johns Hopkins Hospital
AM is a medical advisory board member of the Hydrocephalus Association and was reimbursed for travel and airfare. AM was a consultant to Quest Diagnostics and Orbees Incorporation for market research, receiving payment for consulting. AM undertook research for Fujirebio Diagnostics and received a research grant to his lab at Johns Hopkins University.
Adrian Priesol, MD, FRCPC
Massachusetts Eye and Ear Infirmary
Harvard Medical School
AP declares that he has no competing interests.
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