Wernicke-Korsakoff Syndrome

Question 1

What are the symptoms of Wernicke’s encephalopathy?

Answer 1

Ataxia, ophthalmoplegia, confusion secondary to thiamine (vitamin B1) deficiency.

Question 2

What are the Korsakoff symptoms?

Answer 2

Loss of memories, confabulation, difficulty learning new things

Question 3

How does chronic alcohol consumption lead to thiamine deficiency?

Answer 3

• Inadequate nutritional thiamine intake
• Decreased absorption of thiamine in GI tract
• Impaired thiamine utilisation in cells

Question 4

What else other than thiamine deficiency has been noted to be a common cause Wernicke-Korsakoff Syndrome?

Answer 4

Chronic subdural haematoma

(even when the haematoma had be resolved, the symptoms still persisted due to organic atrophic changes to both the frontal and temporal lobes (due to long term compression))

Question 5

What are the causes of WKS?

Answer 5

• Most common cause is CHRONIC ALCOHOL MISUSE/DEPENDENCE
• Chronic subdural haematoma
• Nutritional stress  bariatric surgery, rapid weight loss, laparotomy for small bowel obstruction
• AIDs
• Thyrotoxicosis
• Cancer
• Long-term dialysis
• CCF (when treated with long term diuretics)

Question 6

What is common presentation for WKS?

Answer 6

A patient who presents with: confusion, nausea, vomiting, fatigue, weakness or apathy and is a known alcohol misuser should be considered HIGH RISK for Wernicke’s encephalopathy. (unexplained hypotension and hypothermia should also increase suspicion)

Question 7

What are symptoms of WKS?

Answer 7

• Vision changes – double vision, eye movement abnormalities, eyelid drooping, nystagmus, ophthalmoplegia
• Loss of muscle coordination - ataxia
• Loss of memory (may be profound)
• Inability to form new memories
• Hallucinations

Question 8

What are acute symptoms of WKS?

Answer 8

Confusion, ataxia, ophthalmoplegia

Question 9

What are chronic symptoms of WKS?

Answer 9

Confabulation, retrograde and anterograde amnesia, peripheral neuropathy and ataxia

Question 10

What are signs of WKS?

Answer 10

• Polyneuropathy may be seen on neuro exam
• Hyporeflexia or abnormal reflexes
• Ataxic on cerebellar examination and any gait examination
• Muscular atrophy
• Nystagmus, bilateral rectus palsy and conjugate gaze palsy
• Hypotension and hypothermia
• Tachycardia
• Pt. may seem cachectic (cachexia = weakness and wasting of body due to severe chronic illness)

Question 11

What are the cognitive features of WKS and what do they mean?

Answer 11

• Confabulation (where there is falsification of memory in clear consciousness e.g. they may have been on ward all day but told someone very convincingly that they left to do something and came back, may also answer questions promptly with inaccurate and bizarre answers).
• Memory Loss/Anterograde Amnesia
o loss of events occurring after onset of disorder
o Inability to learn new tasks or repeat simple pieces of information
o Often disoriented in time and space
• Retrograde amnesia
o Loss of memory for events before onset of disorder
o May preserve some memory of distant events
o Telescoping of events e.g. patient says something happened recently when it actually took place a long time ago

Question 12

What is the criteria for diagnosing encephalopathy?

Answer 12

At least 2 of the 4 should be present:
•	Dietary deficiencies
•	Oculomotor abnormalities
•	Cerebellar dysfunction
•	Either altered mental state or mild memory impairment

Question 13

What blood tests should be done to investigate WKS and what may be found?

Answer 13

o FBC (particularly look at MCV)
o U&ES (exclude hypernatraemia, hypercalcaemia and uraemia)
o LFTs
o Glucose
o ABG (rule out hypercarbia and hypoxia)
o Cholesterol
o Serum thiamine levels (vitamin B1) may be low
o Pyruvate is elevated
o LP may be needed to rule out non-focal CNS infections
o Red cell transketolase activity is decreased in thiamine deficiency but not usually necessary to diagnose condition.

Question 14

What are general principles when managing WKS?

Answer 14

• Address alcohol misuse
• Address diet
• Treat as medical emergency when symptoms are acute
• IV fluids and oxygen for those with altered mental state or pre-coma
• Comatose patients may need intubation to maintain airway patency

Question 15

What pharmacological management is required for WKS?

Answer 15

• Thiamine orally plus vitamin B complex or multivitamins should be given indefinitely
• Oral thiamine should be offered to all harmful or dependent drinkers if either of the following applies:
o They are malnourished  prescribe 50mg oral thiamine per day
o They have decompensated liver disease
• IV Pabrinex (thiamine) for those who cannot take oral medication

Question 16

What percentage of patients recover completely from WKS?

Answer 16

20%

Question 17

What are complications of WKS?

Answer 17

• Korsakoff’s syndrome can develop in untreated or undertreated Wernicke’s
• Recurrence of encephalopathy can recur in patients who continue to drink alcohol and fail to maintain thiamine intake
• CCF may be complication
• Ataxia may persist and cause slow shuffling gait
• Global confusion may be slow to resolve and there may be persisting learning difficulties and memory impairment.

Question 18

Of wernickes encephalopathy and Korsakoff syndrome, which is the medical emergency?

Answer 18

Wernickes encephalopathy

Question 19

When left untreated what is the mortality rate of wernickes encephalopathy?

Answer 19

20%

Question 20

What percentage of untreated wernickes leads to Korsakoff syndrome?

Answer 20

85%

Question 21

Of the patients that develop Korsakoff syndrome, what percentage go on to require long-term institutionalisation?

Answer 21

25%

Question 22

How to prevent WKS?

Answer 22

• Alcohol avoidance

- Thiamine supplementation in those who are alcohol dependent