Alcoholic encephalopathy

Alternative names
Korsakoff psychosis; Wernicke-Korsakoff syndrome; Encephalopathy - alcoholic; Wernicke’s disease

Definition
Wernicke-Korsakoff syndrome is a brain disorder involving loss of specific brain functions caused by a thiamine deficiency.

Causes, incidence, and risk factors
The syndrome is actually a spectrum, including two separate sets of symptoms, one of which tends to start when the other subsides. Wernicke’s encephalopathy involves damage to multiple nerves in both the central nervous system (brain and spinal cord) and the peripheral nervous system (the rest of the body).

It may also include symptoms caused by alcohol withdrawal. The cause is generally attributed to malnutrition, especially lack of vitamin B1 (thiamine), which commonly accompanies habitual alcohol use or alcoholism.

Heavy alcohol use interferes with the metabolism of thiamine, so even in the unusual cases where alcoholics are eating a balanced diet while drinking heavily, the metabolic problem persists because most of the thiamine is not absorbed.

Korsakoff syndrome, or Korsakoff psychosis, tends to develop as Wernicke’s symptoms diminish. It involves impairment of memory out of proportion to problems with other cognitive functions.

Patients often attempt to hide their poor memory by confabulating. The patient will create detailed, believable stories about experiences or situations to cover gaps in memory. This is not usually a deliberate attempt to deceive because the patient often believes what he is saying to be true. It can occur whether or not the thiamine deficiency was related to alcoholism and with other types of brain damage.

Korsakoff psychosis involves damage to areas of the brain involved with memory.

Symptoms

     
  • Vision changes       o Double vision       o Eye movement abnormalities       o Eyelid drooping  
  • Loss of muscle coordination       o Unsteady, uncoordinated walking  
  • Loss of memory, can be profound  
  • Inability to form new memories  
  • Confabulation (making up stories)  
  • Hallucinations

Note: Symptoms that indicate alcohol withdrawal may also be present or may develop.

Signs and tests

     
  • Examination of the nervous/muscular system may show polyneuropathy (damage to multiple nerve systems).  
  • Reflexes may be decreased (or of abnormal intensity), or abnormal reflexes may be present.  
  • Testing of gait and coordination indicates damage to portions of the brain that control muscle coordination.  
  • Muscles may be weak and may show atrophy (loss of tissue mass).  
  • Examination of the eyes shows abnormalities of eye movement.  
  • Blood pressure and body temperature measurement may be low.  
  • Pulse (heart rate) may be rapid.

The person may appear cachectic (malnourished). A nutritional assessment may confirm malnourished state.

     
  • Serum B1 levels may be low.  
  • Pyruvate is elevated.  
  • Transketolase activity is decreased.

If the history is significant for chronic (long-term) alcohol abuse, serum or urine alcohol levels may be elevated (see toxicology screen) and liver enzymes may be elevated.

Other chronic conditions that may cause a thiamine deficiency include the following:

     
  • AIDS  
  • Hyperemesis gravidarum (continuous nausea and vomiting during pregnancy)  
  • Thyrotoxicosis (very high thyroid hormone levels)  
  • Cancers that have spread throughout the body  
  • Long-term dialysis  
  • Congestive heart failure, when treated with long-term diuretic therapy

A brain MRI rarely shows changes in the tissue of the brain indicating Wernicke-Korsakoff syndrome.

Treatment

The goals of treatment are to control symptoms as much as possible and to prevent progression of the disorder. Hospitalization is required for initial control of symptoms.

If the person is lethargic, unconscious, or comatose, monitoring and care appropriate to the condition may be required. The airway should be monitored and protected as appropriate.

Thiamine (vitamin B1) may improve symptoms of confusion or delirium, difficulties with vision and eye movement, and muscle incoordination. Vitamin B1 may be given by injection into a vein or a muscle, or by mouth.

Thiamine does not generally improve loss of memory and intellect associated with Korsakoff psychosis.

Total abstinence from alcohol is required to prevent progressive loss of brain function and damage to peripheral nerves. A well-balanced, nourishing diet is recommended.

Support Groups
The stress of illness can often be helped by joining a support group where members share common experiences and problems. See alcoholism - support group.

Expectations (prognosis)

Without treatment, Wernicke-Korsakoff syndrome progresses steadily to death. With treatment, symptoms (such as uncoordinated movement and vision difficulties) may be controlled, and progression of the disorder may be slowed or stopped.

Some symptoms - particularly the loss of memory and cognitive skills - may be permanent. There may be a need for custodial care if the loss of cognitive skills is severe.

Other disorders related to the abuse of alcohol may also be present.

Complications

     
  • Permanent loss of memory  
  • Permanent loss of cognitive skills  
  • Injury caused by falls  
  • Difficulty with personal or social interaction  
  • Alcohol withdrawal state  
  • Permanent alcoholic neuropathy  
  • Shortened life span

Wernicke’s encephalopathy may be precipitated in at-risk people by carbohydrate loading or glucose infusion. Supplementation with thiamine must precede glucose infusion to prevent this.

Calling your health care provider

Call your health care provider if symptoms suggesting Wernicke-Korsakoff syndrome occur, or if the condition has been diagnosed and symptoms worsen or reappear.

Also call if new symptoms develop, particularly symptoms of alcohol withdrawal. Alcohol withdrawal can be fatal, so call the local emergency number (such as 911) or go to the emergency room if any severe symptoms occur.

Symptoms of alcohol withdrawal include:

Delirium or confusion

     
  • Agitation  
  • Jumpiness or nervousness  
  • Insomnia  
  • Hallucinations  
  • Palpitations  
  • Heart rate that is faster than normal without an observable cause, such as:       o Increased activity       o Pale skin       o Profuse sweating       o Muscle tremors       o Seizures       o Headache       o Fever       o Nausea/vomiting

Prevention
Abstinence or moderate alcohol use and adequate nutrition reduce the risk of developing Wernicke-Korsakoff syndrome. If a heavy drinker is determined not to quit, thiamine supplementation and a good diet may help prevent the development of this condition, but not if damage has already occurred.

Johns Hopkins patient information

Last revised: December 6, 2012
by Simon D. Mitin, M.D.

Medical Encyclopedia

  A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | 0-9

All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.