A 54-year-old homeless man is brought to the emergency department by the police after he was found to be confused and disheveled. The patient is unable to provide a medical history and has no prior hospital record. Temperature is 36.5 C (97.7 F), blood pressure is 110/60 mm Hg, pulse is 90/min, and respirations are 16/min. The patient is thin and appears ill, with temporal muscle wasting. The mucous membranes are dry. The lungs are clear to auscultation, and heart sounds are normal with no murmur. The abdomen is soft, nontender, and nondistended. The patient is disoriented and unable to recognize where he is or state the date. Bilateral pupils are equal and reactive to light, but extraocular motion is restricted on leftward gaze. No obvious motor weakness is present. Deep tendon reflexes are reduced and plantar responses are flexor. The patient has no neck rigidity, but his gait is markedly ataxic. Laboratory results are as follows: Item 1 of 2 Which of the following is the best next step in management of this patient's confusion?

Question

Quizplus · Accepted Answer

Explanation: Wernicke encephalopathy (WE) is a life-threatening disorder of thiamine deficiency seen most commonly in patients with heavy alcohol use and/or severe malnutrition. The classic features of WE include: Encephalopathy - disorientation and confusion Oculomotor dysfunction - lateral rectus palsy Gait ataxia - wide-based gait or complete gait impairment No specific testing for thiamine deficiency is available, but laboratory evidence of alcoholic hepatitis (2:1 ratio of aspartate to alanine aminotransferase) or synthetic hepatic dysfunction (prolonged INR, low albumin) often supports the diagnosis. Treatment with intravenous thiamine, a well-tolerated and low-risk medication, is required with urgency. Because all 3 clinical features of WE are present in <10% of affected patients, treatment is generally given to those in whom the diagnosis is possible (eg, unclear cause of gait ataxia or confusion). Intravenous thiamine usually improves ocular abnormalities within hours, but confusion and gait ataxia may persist for days or weeks; many patients never fully recover. (Choice A) Delirium can be a sign of acute infection, but this patient has no fever or leukocytosis and has classic findings for WE. (Choice B) Although this patient has dry mucous membranes and evidence of malnutrition, providing fluids with glucose (dextrose) prior to thiamine is associated with a worsening of WE symptoms and is not recommended. (Choice C) Lorazepam is a benzodiazepine often used to treat acute alcohol withdrawal. Manifestations typically begin with central nervous system hyperactivity, including insomnia, tremulousness, anxiety, and diaphoresis. This patient may require treatment for alcohol withdrawal, but he is manifesting signs of WE and requires thiamine. (Choice E) Lactulose is commonly used to treat hepatic encephalopathy, which can cause confusion. However, hepatic encephalopathy is not typically associated with ophthalmoplegia. Educational objective: Wernicke encephalopathy is due to thiamine deficiency, which is common in patients with chronic alcoholism. Classic manifestations include the triad of encephalopathy, oculomotor dysfunction, and gait ataxia. Treatment with intravenous thiamine is usually lifesaving and should be considered in any patient with unexplained delirium or ataxia.

A 54-Year-Old Homeless Man Is Brought to the Emergency Department