Wernicke’s Disease

Pathology:

• Thiamine deficiency
1. Found in all natural foods
2. Small stores in the body
3. Biological half life 9-18days
4. Absorption inhibited by alcohol and folate deficiency.
5. Co-enzyme in pyruvate dehydrogenase and transketolase enzymes
6. Involved in many reactions including myelin synthesis
• Lesions distributed symmetrically in structures surrounding the 3^rd and 4^th ventricles
1. Mamillary bodies
2. Dorsomedial thalamus
3. Periaqueductal grey matter
4. Superior cerebellar vermis
5. Ocular motor nuclei
6. Vestibular nuclei

Diagnosis

MRI

• Lesions of:

o Medial thalami

o Mammillary bodies

o Periaqueductal grey matter

• T2/FLAIR, restricted diffusion, contrast enhancement

Epidemiology

• Majority in alcoholics (up to 15% get disease)
• Malnutrition from other causes (including hyperemesis gravidarum)

Clinical

Acute or chronic onset

Triad (10-33% of patients)

1. Opthalmoplegia
2. Ataxia
3. Global confusion

· Thiamine deficiency can also cause peripheral neuritis

· Can cause Beri-Beri (high output heart failure)

Occular disease

• Horizontal nystagmus on lateral gaze
• Lateral rectus palsy (usually bilateral)
• Conjugate gaze palsy
• Rarely Ptosis

Other

• Vomiting
• Disorientated
• Inattentive
• Rarely agitated delirium
• Fever, coma, death in extreme situations

Treatment:

• Thiamine 100mg IM/IV prior to glucose in alcoholic patients (for 5days if they are admitted)
• If disease is suspected need higher dose
1. 300-500mg IV TDS (over 30min to reduce chance of anaphylaxis)

Korsakoff Syndrome

• Memory/cognitive disorder that occurs in association with Wernicke’s
• More common after alcohol induced Wernicke’s
• Features
1. Partial or complete retrograde amnesia
1. Long term memory often relatively preserved
2. Anterograde amnesia
3. Lack of insight
4. Apathy
5. Meagre content in conversation
6. Confabulation
• Basically – abnormal memory and confabulation with otherwise relatively normal cognition
• Only 50% recover

Beri-Beri

• Another complication thiamine deficiency
• Dry
1. Bilateral peripheral neuropathy – sensory and motor
• Wet
1. Peripheral neuropathy PLUS
2. Cardiac failure/cardiomyopathy/peripheral oedema