Wernicke-Korsakoff syndrome

Although these conditions may appear to be two different disorders, they are generally considered to be different stages of Wernicke-Korsakoff syndrome. Wernicke's encephalopathy represents the "acute" phase and Korsakoff's amnesic syndrome represents the "chronic" phase.^[1] The symptoms of Wernicke encephalopathy (WE) commonly include:^[1][2][4]  

• Encephalopathy (profound disorientation or mental confusion, inability to think clearly and indifference)
• Vision problems (including double vision, abnormal eye movements (nystagmus) and eyelid drooping)
• Loss of muscle coordination (ataxia).

Other symptoms may include:^[1][3][4] 

• Delirium tremor
• Coma
• Hypothermia
• Hypotension.

 Korsakoff syndrome (KS) is seen most frequently in people who abuse alcohol after they experience an episode of WE. Most patients with KS show typical WE lesions in the brain.^[5] The main features of Korsakoff's syndrome are impairments in acquiring new information or establishing new memories, and in retrieving previous memories.^[1][4] 

The symptoms include:^[1][2][3][4]

• Loss of memory and inability to form new memories
• Making of stories (confabulation)
• Seeing or hearing things that are not really there (hallucinations)
• Disorientation
• Vision impairment. 

Attention and social behavior are relatively preserved. Affected subjects are able to carry on a socially appropriate conversation that may seem normal to an unsuspecting spectator. Patients with KS are as a rule unaware of their illness. Some patients may have severe cognitive function and global dementia.^[5]

In people with memory impairment, lesions in an area of the brain known as the anterior thalamus are commonly found. The shrinking of the mamillary bodies is also specific for WE, so when  damaged or very small mamillary bodies are found in a demented patient, it is thought that the dementia may be due to alcohol abuse and malnutrition.^[5]

Wernicke- Korsakoff is caused by thiamine deficiency. Thiamine is a cofactor for several key enzymes important in energy metabolism. Thiamine requirements depend on metabolic rate, with the greatest need during periods of high metabolic demand and high glucose intake.^[3][4]

Because of the role of thiamine in cerebral energy utilization, it has been proposed that its deficiency initiates neuronal injury by inhibiting metabolism in brain regions with high metabolic requirements and high thiamine turnover.^[2] 

Thiamine deficiency in alcohol abusers results from a combination of inadequate dietary intake, reduced gastrointestinal absorption, decreased hepatic storage, and impaired utilization.^[4]

Some studies indicate that there may be a genetic predisposition for the disease. Variants in the high affinity thiamine transporter gene have also been implicated.  The SLC19A2 gene provides instructions for making a protein called thiamine transporter 1. This protein is located on the surface of cells, where it works to bring vitamin B1 (thiamine) into cells.^[3]

The goals of treatment are to control symptoms as much as possible and to prevent progression of the disorder. Some people may need to be hospitalized initially to control the symptoms.^[4] Wernicke encephalopathy is an acute syndrome and requires emergency treatment to prevent death and neurologic problems. For this reason, even if the diagnosis is not confirmed, patients should be treated while additional evaluations are completed.^[2][3]

Treatment involves replacement of thiamine and providing proper nutrition and hydration.^[1][3] Intravenous thiamine is the treatment of choice. After the initial dose, daily doses of thiamine are usually recommended. Supplementation of electrolytes, particularly magnesium and potassium (often low in people with alcoholism), may be required in addition to thiamine. In those who are chronically malnourished, the remainder of the B vitamins should also be supplemented. Supplementation can be tapered as the patient resumes normal intake and shows improvement.^[3]

Because long-term alcohol use is the most common cause for Wernicke-Korsakoff syndrome, avoiding alcohol provides the best chance for recovery. Referral to an alcohol recovery program should be part of the treatment regimen.^[3]
 
Due to difficulties with movement, patients should be provided with assistance when walking during the initial phase of treatment. Patients may require physical therapy to assist with movement. Walking difficulties may be permanent, depending on the severity at initial presentation and the timeliness of therapy.^[3]

Patients with Korsakoff syndrome rarely recover. Many patients require at least some form of supervision and social support, either at home or in a chronic care facility. There are some reports of improvement in attention and memory with the use of a medication known as acetylcholinesterase inhibitors and with memantine, but nothing is yet confirmed.^[5]