Definition

Encephalopathy is condition caused by diseases that affect large portions of the brain. The disease may affect the function and/or the structure of the brain leading to a wide range of physical and mental symptoms. An altered mental state, such as confusion and sudden mood changes, is often a hallmark of encephalopathy.

There are several different type of encephalopathy based on the cause. Treating the disease or injury causing the encephalopathy may reverse symptoms in some. Some forms of encephalopathy may result in lasting changes in the brain. If the brain injury is severe and cannot be reversed, the disease can be fatal.

Causes

Encephalopathy is caused by an infection or widespread injury of the brain. Some common causes include:

• Infection
• Head trauma
• Metabolic dysfunction—causes an imbalance in nutrients and electrolytes the brain needs to function
• Brain tumor or increased pressure on the skull
• Exposure to toxins
• Poor nutrition—causes an imbalance in nutrients and electrolytes the brain needs to function
• No oxygen or blood flow to the brain
• Organ failure

Risk Factors

Risk factors vary depending on type of encephalopathy. For example, alcohol abuse puts you at risk for Wernicke’s or Hepatic encephalopathy.

Symptoms

An altered mental state may include:

• Sudden or progressive changes in memory
• Inability to concentrate
• Impaired thinking
• Abnormal drowsiness
• Mood changes
• Progressive loss of consciousness
• Subtle personality changes

Other symptoms may include:

• Involuntary muscle twitches and flapping movements
• Tremor
• Muscle weakness and unsteadiness
• Abnormal eye movements
• Seizures

Signs that encephalopathy may be getting worse include:

• Severe confusion
• Disorientation
• Severe drowsiness
• Coma

Medical care is needed right away for these symptoms.

Diagnosis

Your doctor will ask you or your caregiver about your symptoms and medical history. A physical exam will be done.

To confirm diagnosis and determine the cause or extent of the encephalopathy your doctor may request:

• Blood tests
• Spinal tap—removal of a small amount of spinal fluid for testing
• CT scan or MRI scan—to take pictures of structures inside the brain
• Electroencephalogram (EEG) —a test that records the brain’s electrical activity

Treatment

The goal of treatment is to try to stop or reverse the damage by managing the condition causing the encephalopathy. Treatment is based on the cause but may include:

• Medications—to treat infections, manage related conditions like high blood pressure, remove toxins, and replace missing or low levels of vitamins or nutrients
• Dietary changes—to improve nutrition or manage underlying condition
• Dialysis—to clear harmful substances, like toxins, out of the blood
• Organ transplant

Medical support may be needed through recovery including feeding tube or breathing support with severe encephalopathy.

Prevention

Many causes cannot be prevented. Take these steps to help reduce your chance of getting encephalopathy:

• Get early treatment for liver problems. If you have any of the above symptoms, call your doctor right away.
• If you have a disease, see your doctor regularly.
• Avoid overdosing on drugs, alcohol, or medicines.
• Avoid being exposed to poisons or toxins and infections or carriers of infections, such as mosquitoes.

National Institute of Neurological Disorders and Stroke http://www.ninds.nih.gov/

Health Canada http://www.hc-sc.gc.ca/index-eng.php

Encephalopathy. Congress of Neurological Surgeons website. Available at:
http://wiki.cns.org/wiki/index.php/Encephalopath
Updated July 2007. Accessed May 26, 2011.

NINDS encephalopathy page. National Institute of Neurological Disorders and Stroke website. Available at:
http://www.ninds.nih.gov/disorders/encephalopathy/encephalopathy.htm
Accessed October 23, 2014.