Altered mental state is the major symptom of encephalopathy. In addition, affected individuals will also experience confusion, lethargy, depression, personality changes, poor cognitive functioning, nystagmus, seizures, tremor, asterixis, myoclonus and jactitation. Individuals suffering from encephalopathy may also develop respiratory abnormalities such as apneustic respirations, Cheyne-Stokes respiration and post–hypercapnic apnea.

Series of tests will be performed for diagnosis of encephalopathy. A past history and medical profile of the affected individual will be taken. Thereafter, the signs and symptoms of neurological functioning will be assessed. In addition, the following procedures will be done to diagnose the condition:

• Blood tests will be done to analyze the underlying cause of the disease.
• Spinal tap to identify a possible causative organism.
• Imaging studies such as CT scan and MRI scan of the brain would be done to evaluate the extent of damage that has taken place [7].
• Electroencephalography (EEG) will also be carried out to measure the electrical activity of the brain [8].

Treatment depends on the type and severity of the condition. In many cases, the symptoms are managed through medications. Surgery is required to treat underlying condition. Affected individuals are put on specialized diet and nutritional supplements, for effective management of the symptoms.

For patients with Wernicke encephalopathy, administration of 500 mg of thiamine 2 to 3 times a day helps in reversing the condition [9]. For patients with hypertensive encephalopathy, the medications that need to be administered in addition to effectively reducing the blood pressure should also cause no adverse effects to the nervous system. Such type of medications includes nicardipine, labetalol and esmolol [10].

Prognosis of the disease depends on the type of encephalopathy that has set in. By treating the underlying disease, the condition can be well managed. However, in several cases, encephalopathy may present with severe damage to the brain and neurological functioning. In addition, certain forms of encephalopathy are fatal.

Encephalopathy can be caused due to bacterial infections, exposure to toxic compounds for longer durations and certain disease condition such as brain tumors or increase in pressure in the skull. In many cases, encephalopathy may also result from poor nutrition and is known as Wernicke encephalopathy. The encephalopathy that results from liver disease is known as hepatic encephalopathy and the one that occurs due to trauma is termed as chronic traumatic encephalopathy [2].

Similarly, when the condition occurs due to high blood pressure, it is termed as hypertensive encephalopathy, the one that occurs due to kidney failure is termed as uremic encephalopathy and when toxins are the cause it is known as toxic encephalopathy. In many cases, Lyme disease can also cause encephalopathy and the condition is known as Lyme encephalopathy.

The incidence of Wernicke encephalopathy is higher in males than females, probably because of increased alcohol consumption amongst the male population that eventually leads to Vitamin B1 deficiency. The male to female ratio for Wernicke encephalopathy is 1.7:1 [3].

Hypertensive encephalopathy is a common occurrence in the middle aged population. The condition is more prevalent amongst the White race due to high incidence of hypertension in this population. 

The annual expenditure incurred towards hepatic encephalopathy in the US is estimated to be $1 billion - $7 billion [4].

Many types of encephalopathy gradually cause irreversible damage to the brain. For individuals with long history of hypertension, arteriolar damage followed by necrosis occurs. This in turn causes cerebral edema and papilledema which are characteristics of altered mental state [5].

Wernicke encephalopathy can occur amongst the drinker’s population. Alcohol interferes with the uptake and utilization of thiamine which in turn leads to its deficiency. However, the condition can also occur amongst those individuals who do not drink alcohol but are highly deficient in thiamine due to starvation or poor dietary habits. Deficiency in thiamine can progressively cause neurologic injury causing onset of encephalopathy [6].

Some forms of encephalopathy can be prevented. Individuals should avoid alcohol consumption to avoid thiamine deficiency. In addition, individuals who have suffered from hypertensive encephalopathy should make certain life style modifications to prevent recurrent attacks. Modification in dietary habits should also be made with special emphasis to a low sodium diet. This would help in keeping the blood pressure from rising and preventing further complications.

There are several types of encephalopathy; some of which are present from birth while some are acquired later in life. Certain types of encephalopathy are temporary in nature; whereas some are permanent which gradually worsen as the disease progresses [1].

Definition

Encephalopathy is a condition characterized by global dysfunction of the brain. There are several types of encephalopathy which have been classified based on the causative factor. The damage caused to the brain and neurological functioning can be reversible or irreversible depending on the type of encephalopathy that has set in.

Cause

Alcohol abuse, inadequate nutrition, thiamine deficiency, long term exposure to toxins, high blood pressure, bacterial infections and autoimmune diseases can all cause encephalopathy. The type of encephalopathy depends on the causative factor and the disease is named accordingly. For example if alcohol abuse is the cause, then the encephalopathy that sets in is known as Wernicke encephalopathy. Similarly for those who have long standing history of high blood pressure are prone to develop hypertensive encephalopathy.

Symptoms

Encephalopathy presents with altered mental state which is characterized by confusion, memory loss, personality changes, poor cognitive functioning and lack of concentration. Individuals with encephalopathy also develop nystagmus, asterixis, seizures, tremors and jactitation.

Diagnosis

Diagnosis of encephalopathy is made by carefully studying the signs and symptoms. In addition, blood tests and lumbar puncture tests are also done. Imaging studies such as CT scan and MRI also form an important part of the diagnostic procedure.

Treatment

Medications form the basis of the treatment regime. These are administered to help manage the symptoms and treat underlying conditions as well. Changes in dietary habits and nutritional therapy may also be required.

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