Last reviewed: July 2020
Last updated: March  2018



History and exam

Key diagnostic factors

  • hx 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 diarrhea
  • mild irritability
  • delirium
  • acute psychosis
  • coma
  • miosis, anisocoria, light/near dissociation
  • papilledema, retinal hemorrhages
  • tachycardia or hypotension
  • hypothermia or hyperthermia
  • hearing loss, seizures, and spastic paraparesis
  • ataxia

Risk factors

  • alcohol dependence
  • AIDS
  • cancer and treatment with chemotherapeutic agents
  • malnutrition
  • hx of GI surgery
  • genetics
  • bone marrow transplantation
  • infants who have been fed formula milk deficient in thiamine
  • male gender

Diagnostic investigations

1st investigations to order

  • therapeutic trial of parenteral thiamine
  • finger-stick glucose
  • CBC
  • serum electrolytes
  • renal function
  • LFTs
  • urinary and serum drug screen
  • serum ammonia
  • blood alcohol level
  • blood thiamine and its metabolites
  • serum magnesium
More 1st investigations to order

Investigations to consider

  • lumbar puncture
  • MRI of brain
  • CT of brain
More investigations to consider

Treatment algorithm


Assistant Professor

Department of Neurology

Johns Hopkins Hospital




AM declares that he has no competing interests.

Peer reviewersVIEW ALL


Massachusetts Eye and Ear Infirmary

Harvard Medical School




AP declares that he has no competing interests.

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