Wernicke’s Encephalopathy

Question 1

Definition of wernicke’s encephalopathy

Answer 1

Neurological emergency that is caused by thiamine deficiency which is commonly seen in alcoholics. Can lead to neurocognitive manifestations

Question 2

Aetiology of wernicke’s encephalopathy

Answer 2

Thiamine deficiency most commonly seen in CHRONIC ALCOHOL CONSUMPTION
Also in eating disorders, malnutrition, prolonged vomiting
Deficiency can be due to:
‣ Inadequate dietary intake
‣ Reduced GI absorption
‣ Relative deficiency due to increased demand

Question 3

Pathophysiology of wernickes encephalopathy

Answer 3

• Thiamine deficiency leads to decreased activity of thiamine dependent enzymes
• This would trigger a series of events that would cause neuronal death
• The effect on memory circuits can lead to an important sequela:
◦ Korsakoff’s psychosis: leads to antero- and retrograde amnesia and confabulation (producing false memories WITHOUT the intent to deceive

Question 4

History and examination of wernicke’s encephalopathy

Answer 4

• Classical triad:
• Confusion
• Ataxia: gait ataxia/dysfunction
• Opthalmoplegia: nystagmus, lateral rectus palsy or conjugate gaze palsies

• Mental slowing, impaired concentration and apathy: likely to have some cognitive dysfunction
• Ocular motor findings: gaze palsies, impaired vestibulo-ocular reflexes
• Mild irritability
• Delirium
• Acute psychosis
• Tachycardia, hypotension

Question 5

Risk factors for wernicke’s encephalopathy

Answer 5

• Alcohol dependence
• AIDS
• Cancer treatment
• History of GI surgery

Question 6

Treatment of wernicke’s encephalopathy

Answer 6

1) Stabilisation/resuscitation + thiamine + magnesium + multivitamins: airway needs to be protected depending on consciousness level. High dose parenteral thiamine recommended (Pabrinex)

Question 7

Prevention and prognosis of Wernicke’s encephalopathy

Answer 7

• Alcohol cessation and appropriate thiamine supplementation

• High risk of permanent brain injury if left untreated. Can also lead to death

Question 8

Complications of wernickes encephalopathy

Answer 8

• Korsakoff’s psychosis: long term consequence of thiamine deficiency
• Hearing loss
• Ataxia and varying degrees of opthalmoparesis