- Wernicke’s Encephalopathy (WE): ACUTE neuro/cardiovascular sx caused by thiamine deficiency
- Korsakoff’s Psychosis (KP): CHRONIC neurologic symptoms caused by thiamine deficiency
- Wernicke-Korsakoff Syndrome (WKS): presence of WE + KP simultaneously
- Only 20% identified before death, failure of dx leads to 20% mortality and 75% permanent damage
- Brain lesions/atrophy occurs: mamillary bodies (nearly all cases), thalamus, periaqueductal gray matter, 3rd/4th ventricle, cerebellum, frontal lobe
- Thiamine is a cofactor for enzymes required in:
- krebs cycle
- Pentose phosphate pathway
- Alpha-ketoglutarate dehydrogenase, pyruvate dehydrogenase.
- Because thiamine is an important cofactor in critical pathways for energy production, deficiency results in lactic acidosis and alteration of brain metabolism.
- Thiamine is also important for lipid metabolism and may affect myelin sheath formation. This may explain peripheral neuropathy symptoms in dry beriberi.
- Anything that causes thiamine (vitamin B1) deficiency: poor dietary intake, malabsorption, increased metabolic requirement
- Chronic alcoholism, dieting/fasting/starvation, anorexia, vomiting/diarrhea, unbalanced TPN, GI surgery, malignancy, dialysis, AIDS, IBD, pancreatitis, liver disease, thyrotoxicosis
- Classic triad: encephalopathy, oculomotor dysfunction, gait ataxia
- werNICke mnemonic:
- N: Nystagmus/ophthalmoplegia. Ocular findings may also include bilateral 6th nerve palsy, conjugate gaze palsy, pupillary abnormality, retinal hemorrhage, ptosis.
- I: Incoordination/ataxia
- C: Confusion/memory impairment
- Other sx: hypotension, tachycardia, EKG abnormalities, DOE, CHF sx, hypothermia, coma, dry/wet Beriberi
- Sx: anterograde/retrograde amnesia, confabulation, confusion, apathy
- Sx: combination of WE and KP
Thiamine deficiency types
WE/KP/WKS = clinical diagnoses.
Wernicke's Encephalopathy diagnosis requires at least 2 out of the following 4 clinical criteria:
- Nutritional deficiency
- Ocular findings (ophthalmoplegia, nystagmus)
- Mental status change
If you suspect WE/KP/WKS then treat it! Diagnosis is clinical and difficult to confirm, treatment is simple/inexpensive/effective, there is little risk to treatment, and the risk of morbidity/mortality from not treating is high
- Suspected WE/KP/WKS: thiamine 500 mg IV over 30 min TID x 2 days, then 500 mg IV/IM q day for 5 days, then 100 mg PO q day until pt no longer at risk
- Give magnesium; hypomagnesemic state may be resistant to thiamine administration
- Treatment can take days to weeks to work if at all (despite accurate diagnosis)
- Give thiamine BEFORE glucose in patients requiring glucose who are at risk for thiamine deficiency; glucose without thiamine can precipitate/worsen WE by driving thiamine intracellularly
Vitamin Prophylaxis for Alcoholics
- For the majority of chronic alcoholics, you should not administer a banana bag (thiamine 100 mg + magnesium 2-4 g + folate 1 mg + multivitamin; all in 1L NS or D5W)
- At risk for thiamine deficiency but no symptoms: thiamine 100 mg PO q day
- Give multivitamin; pt at risk for other vitamin deficiencies
- Alcohol (ETOH) Intoxication
- Alcoholic ketoacidosis
- Alcohol withdrawal: Inpatient management
- Alcohol withdrawal: Outpatient management
- Alcohol withdrawal seizures
- Delerium tremens
- Thiamine deficiency
- Donnino, Michael, et al. “Myths and misconceptions of wernicke’s encephalopathy: what every emergency physician should know.” Annals of emergency medicine. 2007. Vol 50, no 6. Pages 715-721.
- Sechi, GianPietro; Serra, Alessandro. “Wernicke’s encephalopathy: new clnical settings and recent advances in diagnosis and management.” Neurology. Vol 6, May 2007. Pages 442-455
- Krishel, S, et al. Intravenous Vitamins for Alcoholics in the Emergency Department: A Rreview. The Journal of Emergency Medicine. 1998; 16(3):419–424.
- Li, SF, et al. Vitamin deficiencies in acutely intoxicated patients in the ED. The American Journal of Emergency Medicine. 2008; 26(7):792–795.