What Is Encephalopathy?

Types, Causes, Symptoms, Diagnosis, Treatment, and More

In This Article

The term encephalopathy means any type of damage or disease affecting the brain. This occurs when there is a change in the way the brain works or the way in which the body affects the brain. These changes can lead to abnormalities in brain function. 

Encephalopathy is not a single disease, but rather a group of disorders with numerous causes. These conditions are serious and without treatment, can lead to temporary or permanent brain damage, loss of consciousness, and even death.

Here is what you need to know about encephalopathy and its types, causes, symptoms, and more.

Encephalopathy can occur in military personnel and football players
SDI Productions / E+ / Getty Images

Types of Encephalopathy and Causes

Below are some of the more common types of encephalopathy, along with their causes.

Chronic Traumatic Encephalopathy

Chronic traumatic encephalopathy (CTE) is a progressive (gradually increasing) and degenerative (worsening) brain condition linked to repeated blows to the head over a long time period.

While prevalence for CTE isn’t truly known, this type of encephalopathy tends to affect athletes in contact sports (like American football), military personnel who have been exposed to repetitive blunt head trauma, and even victims of domestic abuse.

Symptoms of CTE don’t develop right away after head trauma. It will take years or decades of repeated head trauma. Symptoms include problems with thinking, depression, memory problems, impulsive behavior, and difficulty with making decisions and carrying out tasks.

Hashimoto’s Encephalopathy

Hashimoto's encephalopathy (HE) is associated with Hashimoto's thyroiditis, an autoimmune thyroid disease caused by an underactive thyroid. HE has an estimated prevalence of 2.1 per population of 100,000. Researchers think this number is higher due to many misdiagnosed or underdiagnosed cases because the condition is not well-known.

HE symptoms include seizures, confusion, and dementia. It is also known to cause psychosis, including visual hallucinations and paranoid delusions.

Hypoxic-Ischemic Encephalopathy

Hypoxic-ischemic encephalopathy (HIE)—also known as global hypoxic-ischemic injury—is a type of brain dysfunction that happens when the brain doesn’t get enough blood flow for a period of time. This type of injury can result in permanent brain damage.

In adults, this type of brain damage is related to a cardiac arrest or cerebrovascular disease (blood vessel disease). In older children, common causes include drowning and choking.

In newborns, HIE can happen in a variety of ways prior to birth, during the birth process, after birth. This can include problems related to the mother’s pregnancy, trauma during delivery, placenta blood clots, and umbilical knots.

Some people who develop HIE will recover; others may suffer permanent brain damage or die.

Hypertensive Encephalopathy

Hypertensive encephalopathy causes general brain dysfunction due to significantly high blood pressure. Symptoms of hypertensive encephalopathy include headaches, vomiting, balance problems, and confusion. If this condition gets serious, it can lead to seizures or bleeding in the back of the eye.

Hypertensive encephalopathy is commonly seen in people with kidney failure and those who abruptly stop taking their blood pressure medications. Hypertensive encephalopathy is also found among those who do not have easy access to healthcare.

Infectious Encephalopathies

Infectious encephalopathies are the most serious types of encephalopathies. They result from transmissible spongiform encephalopathies, also known as prion diseases. These encephalopathies are characterized by tiny holes that give the brain a spongy-like appearance.

Infectious encephalopathies are neurogenerative—meaning they cause damage to the brain and its function that gets worse over time. Examples of prion diseases that lead to infectious encephalopathy include chronic wasting disease, fatal familial insomnia, and Creutzfeldt-Jakob disease.

Metabolic Encephalopathy

Metabolic encephalopathy occurs when another health condition—like diabetes, kidney failure, heart failure, or liver disease—makes it hard for the brain to work. For example, high blood sugar can lead to confusion or a coma.

Neurological symptoms are common if the underlying cause isn't well-treated and severity will depend on what happens with that condition. Fortunately, brain problems associated with metabolic encephalopathies are generally reversible.

Wernicke Encephalopathy

Wernicke encephalopathy (WE) causes neurological symptoms related to biochemical lesions of the central nervous system. This occurs when vitamin B reserves, especially thiamine (vitamin B1), are exhausted.

WE is often caused by alcoholism. Symptoms may include confusion, loss of mental acuity, vision changes, and problems with muscle coordination.

Uremic Encephalopathy

Uremic encephalopathy is found in people with kidney failure. It can cause a buildup of uremic toxins in the bloodstream that eventually travel to the brain.

Symptoms include lethargy, confusion, seizures, or coma. Uremic encephalopathy is treated with dialysis or a kidney transplant.

Glycine Encephalopathy

Glycine encephalopathy is a genetic or inherited condition. It causes abnormally high levels of glycine (an amino acid) in the brain.

Symptoms of this type of encephalopathy appear in infants right after birth and include lack of energy, feeding problems, poor muscle tone, abnormal jerking movements, and breathing problems.

Hepatic Encephalopathy

Hepatic encephalopathy is often diagnosed in people with cirrhosis—chronic liver damage that has led to scarring and liver failure. Hepatic encephalopathy causes brain function to decline from severe liver disease. 

With hepatic encephalopathy, the liver cannot adequately remove toxins from the blood and these toxins build up in the bloodstream eventually leading to brain damage.

This type of encephalopathy can either be short-term or chronic (long-term). In some instances, a person with this condition can become unresponsive and fall into a coma.

Encephalopathy Symptoms

The symptoms of encephalopathy depend on the type of cause of encephalopathy. However, some of the most common symptoms include:

  • Confusion
  • Forgetfulness
  • Personality changes
  • Concentration troubles

Some people with encephalopathy may experience:

  • Seizures
  • Sleep problems
  • Muscle weakness
  • Uncontrollable muscle twitches
  • Tremors
  • Trouble speaking
  • Trouble swallowing

If you or a loved one develop any of these symptoms, you should call your doctor right away and follow their instructions on how to proceed.

If you or your loved one have already been diagnosed with encephalopathy, be aware of the following complications:

  • Severe confusion
  • Severe disorientation
  • Coma 

These are signs of a medical emergency that require immediate care.

Diagnosis

To make a diagnosis of encephalopathy, your doctor will ask about your medical history and all medications you are taking. They will also give you a physical examination and request additional tests.

Tests that can help in diagnosing an encephalopathy condition include:

  • Tests to check your concentration, memory, and other mental acuity functions
  • Blood tests to look for bacteria, viruses, toxins, hormonal or chemical imbalances, prions, and other medical problems
  • A spinal tap where your clinician will take a sample of spinal fluid to be examined for bacteria, viruses, toxins, or prions
  • Imaging studies, including computed tomography (CT) or magnetic resonance imaging (MRI)
  • An electroencephalogram (EEG) test to measure electrical activity in the brain

The results of testing can help your doctor to determine if you have an encephalopathy condition, the type of encephalopathy, and the cause or causes.

Treatment

Untreated encephalopathy can lead to permanent damage or loss of life. Treatment for encephalopathy often depends on its underlying cause.

Generally, treatment includes medications to treat symptoms or the underlying condition, as is the case with metabolic encephalopathy. For example, with Hashimoto’s encephalopathy, standard therapy includes glucocorticoids and immunosuppressive medications.

Treatment for chronic traumatic encephalopathy may include behavior therapy, pain management, and memory exercises to strengthen the ability to recall daily events.

If a person is experiencing seizures, their doctor may prescribe anticonvulsant drugs. They may also recommend nutritional supplements to slow down brain damage or to treat an underlying condition.

In rare cases, severe encephalopathy can cause loss of consciousness or coma. If this happens, you will need life support to recover.

Prevention

Some types of encephalopathy can be prevented while others are not preventable. For example, genetic types of encephalopathy, like glycine encephalopathy, aren’t preventable but other encephalopathy types, like hepatic encephalopathy, might be.

Making lifestyle changes may reduce your risk of developing underlying causes of encephalopathy.

Changes could include:

  • Avoiding excess alcohol consumption
  • Reducing exposure to toxins
  • Eating a healthy diet, exercising, and maintaining a healthy weight
  • Seeing your doctor regularly
  • Avoiding medications that affect the nervous system
  • Reducing the potential for head trauma

A Word From Verywell

Your doctor is in the best position to provide information about your encephalopathy outlook. They can work with you and your loved ones on ongoing treatment options and therapies for treating symptoms and managing any brain damage.

If you experience symptoms of encephalopathy, especially decreased mental ability, confusion, decreased muscle coordination, and vision or eye changes, it is important to seek immediate medical help. The sooner you get medical attention, the sooner you can recover from impaired brain function and other encephalopathy symptoms. 

Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Pinson R. Encephalopathy. ACP Hospitalist. January 2015.

  2. Baugh CM, Robbins CA, Stern RA, et al. Current understanding of chronic traumatic encephalopathy. Curr Treat Options Neurol. 2014;16(9):306. doi:10.1007/s11940-014-0306-5

  3. Liyanage CK, Munasinghe TMJ, Paramanantham A. Steroid-responsive encephalopathy associated with autoimmune thyroiditis presenting with fever and confusionCase Rep Neurol Med. 2017;2017:3790741. doi:10.1155/2017/3790741

  4. Heinz UE, Rollnik JD. Outcome and prognosis of hypoxic brain damage patients undergoing neurological early rehabilitation. BMC Res Notes. 2015;8:243. doi:10.1186/s13104-015-1175-z

  5. Allen KA, Brandon DH. Hypoxic ischemic encephalopathy: Pathophysiology and experimental treatments. Newborn Infant Nurs Rev. 2011;11(3):125-133. doi:10.1053/j.nainr.2011.07.004

  6. Sharifian M. Hypertensive encephalopathy. Iran J Child Neurol. 2012;6(3):1-7.

  7. Centers for Disease Control and Prevention. Prion diseases. Updated October 9, 2018.

  8. Angel MJ, Young GB. Metabolic encephalopathies. Neurol Clin. 2011;29(4):837-882. doi:10.1016/j.ncl.2011.08.002

  9. Sinha S, Kataria A, Kolla BP, et. al. Wernicke encephalopathy-Clinical Pearls. Mayo Clin Proc. 2019;94(6):1065-1072. doi:10.1016/j.mayocp.2019.02.018

  10. Seifter JL, Samuels MA. Uremic encephalopathy and other brain disorders associated with renal failure. Semin Neurol. 2011;31(2):139-143. doi:10.1055/s-0031-1277984

  11. Genetic and Rare Diseases Information Center. Glycine encephalopathy. Updated November 18, 2017.

  12. Genetic and Rare Diseases Information Center. Hepatic encephalopathy. Updated June 22, 2016. 

  13. Berisavac II, Jovanović DR, Padjen VV, et al. How to recognize and treat metabolic encephalopathy in neurology intensive care unit. Neurol India. 2017;65:123-8.

  14. Cleveland Clinic. Chronic traumatic encephalopathy (CTE). Updated January 12, 2018.