Wernicke-Korsakoff Syndrome (WKS)
by Clive Evers
Wernicke's encephalopathy (WE) is an acute neurological illness caused by severe deficiency of the vitamin thiamine (vitamin B 1).
It can occur suddenly and is characterised by problems with the eyes, problems with gait and balance, and an overall confusional state.
Alcoholism is usually the cause of thiamine deficiency but cases of WE can also be attributed to anorexia nervosa and disorders associated with high levels of vomiting.
WE can be reversed by dosage of thiamine. WE is a medical emergency and if left untreated will result in coma and death. Wernicke-Korsakoff syndrome is characterised by amnesia and a number of specific memory impairments.
Additionally there is a tendency towards confabulation. The confabulation can be momentary fantastic when they produce grandiose descriptions which are repeated.
Wernicke's encephalopathy; Korsakoff's psychosis; Korsakoff's syndrome; Korsakoff's amnesic syndrome.
Symptoms and course
WKS can occur suddenly and problems with the eyes include disorders of their control of direction, coordination and movement; problems with gait and a loss of balance or equilibrium called ataxia; and a global confusional state where the person is apathetic, has little awareness of their immediate situation and difficulties with space, attention and concentration.
The symptoms of amnesia fall into two broad categories of impaired memory function and retained memory function. In impaired memory there is a profound difficulty or total inability to learn new material and the lack of a normal short term memory (where a person would be able to repeat a telephone number after looking it up). This is known as anterograde amnesia. Also the person cannot remember events in their past life particularly the period immediately before their amnesia. This is known as retrograde amnesia.
However, some memory functions can be well retained. Particularly early established skills and habits. The use of language, gesture, and well practised skills may remain unaffected.
However people can also show a tendency towards decreased initiative and spontaneity and a blunting of effect, so events, which would normally be of emotional significance are reacted to in a dull or apathetic manner.Other psychiatric symptoms include depression, irritable spells and paranoia.Patients who have abused alcohol for many years are also likely to show some of the physical effects such as liver, stomach, and blood disorders.
Causes and risk factors
The main cause of Wernicke-Korsakoff syndrome is chronic alcohol abuse which results in severe deficiency of the vitamine thiamine (vitaminE B1).
However this deficiency can also arise as a result of forced or self-imposed starvation eg anorexia nervosa or from protein-energy malnutrition resulting from inadequate diet or malabsorption.
Conditions associated with protracted vomiting may also be a cause including severe vomiting during pregnancy. People with kidney conditions which may result in chronic renal failure may be at risk. The condition has been described in patients receiving dialysis. Consuming large quantities of carbohydrates when thiamine levels are very low can be a cause (feeding after starvation).
Total population figures for the prevalence have proved very difficult to estimate (Blansjaar et al, 1992). In the Hague, The Netherlands gave a prevalence figure of 48 per 100,000 total population while price (1985). In queensland, Australia estimated there were 6.5 per 100,000 new cases each year.
Doctors will look for an ALTERED MENTAL state in the patient and for other neurological abnormalities. They will take a careful history from the patient and relative/carer, undertake a physical EXAMINATION, laboratory tests and X-RAY to exclude other causes of neurological dysfunction.
We remains a clinical diagnosis with no abnormalities in eg cerebrospinal flui, brain imaging or EEGs.
A complete blood count excludes severe anemias and leukemias as causes of altered mental state. Alterations in serum electrolytes like hypernatremia or hypercalcemia can cause altered mental statusserum glucose will be determined to exclude hypoglycemia and hyperglycemiato exclude uremia BLOOD UREA NITROGEN AND creatinine will be tested.
Arterial blood gases may be tested to exclude hypoxia and hypercarbiatoxic drug screening may be given to exclude some causes of drug induced altered mental status.a lumbar puncture may be considereda head ct scan is the definitive test for emergency diagnosis of focal neurologic disease.it may be necessary to consider EEG's for some patients to exclude an epileptic state as a cause of coma and altered mental state.
(Source: P Salen www.emedicine.com).
Care and treatment
Wernicke's encephalopathy must be viewed as a medical emergency even if there are other possible DIAGNOSES that are being considered. As the condition is potentially reversible, patients with any combination of the above symptoms should be treated with thiamine.
As little as 2mg of thiamine may be enough to reverse the eye problems but initial higher doses of at least 100mg are advisable. Thiamine solutions should be fresh as old solutions may be inactive. The problems of gait and acute confusional state may improve dramatically although improvement may not be noted for days or months. After thiamine has been started doctors may consider treatment with GLUCOSE.
They will carefully monitor the cardiovasculatr status of patients. Doctors will investigate the patients magnesium levels and correct any deficiency. Some drug treatments have been tried INCLUDING THE SELECTIVE SEROTONIN re-uptake inhibitor FLUOXAMINE AND a drug called clonidine to improve memory. HOWEVER THERE is still no satisfactory evidence that any of these or OTHER DRUGS should be used in ordinary clinical practice.
There is some evidence that good social supports can bring a good social outcome in alcohol misue. There is some experience and evidence that memory rehabilitation and therapies may have be of some benefit to patients. These would include external aids like diaries and reminders; the use of mnemonics to help memory; attendance at memory groups. However only a few patients with WK have been tried with these techniques. Referral of patients with alcoholism to drinking cessation programmes and monitoring them for signs of alcohol withdrawal is a key step in outpatient treatment. There is some evidence of the effectiveness of specialist units for patients with WE syndrome.
Medical Council on Alcohol 3 St Andrew's Place Regent's Park London NW1 4LB United Kingdom Registered charity no. 265242 Tel: + 44 (0)20 7487 4445 Fax: + 44 (0)20 7935 4479
Family Caregiver Alliance 690 Market Street, Suite 600 San Francisco, CA 94104 (415) 434-3388 (800) 445-8106 http://www.caregiver.org/caregiver/jsp/content_node.jsp?nodeid=580 firstname.lastname@example.org
Last Updated: vendredi 09 octobre 2009