Last reviewed: 23 Dec 2021
Last updated: 19 Aug 2020



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 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
  • history of gastrointestinal surgery
  • genetics
  • bone marrow transplantation
  • infants who have been fed formula milk deficient in thiamine
  • male sex

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

Investigations to consider

  • lumbar puncture
  • MRI of brain
  • CT of brain

Treatment algorithm



Abhay Moghekar, MB BS

Assistant Professor

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.

Peer reviewers

Adrian Priesol, MD, FRCPC


Massachusetts Eye and Ear Infirmary

Harvard Medical School




AP declares that he has no competing interests.

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