Hepatic Encephalopathy

Hepatic Encephalopathy

Overview

Hepatic encephalopathy is brain dysfunction caused by liver dysfunction. “Encephalopathy” is brain dysfunction, and “hepatic” means liver-related.

Encephalopathy affects your central nervous system and how you think, feel and act. Symptoms can range from confusion and disorientation to erratic behavior and personality changes. It can get better with treatment, but it can be life-threatening without.

Hepatic encephalopathy is caused by neurotoxins in your blood — substances that are toxic to your brain and nervous system. Normally, your liver filters these toxins from your blood. But if your liver isn’t performing this function as usual, the neurotoxins continue to circulate. Eventually, they enter and affect your brain. This usually happens in advanced liver disease, when liver functions begin to fail.

Symptoms

Hepatic encephalopathy can show up in a wide variety of ways. Not everyone will have every symptom. It can affect your:

Mood and personality.

Behavior and impulse control.

Memory, concentration and thinking.

Consciousness, lucidity and sleep patterns.

Coordination and motor functions.

Autonomy and ability to care for yourself.

Symptoms may occur suddenly or come on gradually, and they may be steady and lasting or come and go in episodes. They may get better or worse, depending on your overall health condition. Hepatic encephalopathy can be mild to severe, and symptoms may be barely noticeable to striking. Healthcare providers sometimes group symptoms by their severity as a way of grading, or staging, the disease.

Grading system

The West Haven Criteria is the most common grading system healthcare providers use for hepatic encephalopathy. It grades symptoms on a scale of 0 to 4. Stages 0 to 1 are sometimes called minimal hepatic encephalopathy (MHE) or covert HE. Symptoms in these stages may not be outwardly noticeable. Stages 2 to 4, also called overt hepatic encephalopathy, feature more obvious symptoms.

Symptoms by grade

Possible symptoms by grade include:

Grade 0

Subtle changes in short-term memory, concentration and reaction time, only recognizable perhaps to you or those closest to you. They might show up on standard neuropsychological tests.

Grade 1

Mild confusion or forgetfulness.

Mood swings, like euphoria or anxiety.

Difficulties adding and subtracting.

Difficulties with fine motor skills, like writing.

Sleeping during the day and waking at night.

Grade 2

Clear personality changes.

Inappropriate or out-of-character behaviors.

Lethargy and apathy.

Disorientation in time (what day or year is it?).

Slurred speech (dysarthria).

Grade 3

Slow thinking and sluggish movements.

Disorientation in space (Where am I?).

Drowsiness and loss of general awareness.

Severe confusion, delirium or amnesia.

Involuntary twitching, tremors or asterixis.

Grade 4

Total loss of consciousness (coma).

Any symptoms of overt hepatic encephalopathy are serious. It’s important to treat the condition as soon as possible to prevent it from worsening or causing permanent damage. Severe hepatic encephalopathy can advance to coma or even death. If you see Grade 3 symptoms, like severe drowsiness, confusion or amnesia, disorientation in space and time, or involuntary movements, treatment is especially urgent.

Causes

Hepatic encephalopathy happens when your liver doesn’t filter neurotoxins out of your blood as it normally would. This might be because your liver has temporarily or permanently lost some of its function (liver failure). It might also be because the blood that normally passes through your liver for filtering isn’t passing through it anymore (portosystemic shunt). Sometimes, both things are happening.

The blood your liver filters comes directly from your digestive system, via your portal vein (portal circulation). This blood carries waste products left over from the digestive process, including ammonia and others. Your liver filters them out before sending the blood back out to your body (systemic circulation). If it doesn’t, they build up in your blood and eventually damage your brain tissues. 

Types of hepatic encephalopathy

Healthcare providers define different types of hepatic encephalopathy based on the original cause.

Type A

Type A is caused by acute liver failure. This is a sudden loss of liver function due to a sudden, severe liver injury. Viral infections, autoimmune liver disease and acetaminophen poisoning are common causes. Cerebral edema, swelling in your brain, is a frequent side effect that may contribute to the effects of hepatic encephalopathy. Acute liver failure is an emergency and some cases may require a liver transplant.

Type B

Type B is caused by a portosystemic shunt. A shunt is when blood flow bypasses its normal route through a new, abnormal passageway. A portosystemic shunt is when your portal circulation bypasses your liver on its way to your systemic circulation. Your body may create a shunt if there's a blockage in the normal pathway. Sometimes, a healthcare provider creates one for you for the same reason (transjugular intrahepatic portosystemic shunt, or TIPS). Hepatic encephalopathy is a possible complication in both cases.

Type C

Type C is caused by chronic liver failure. Chronic liver failure is the gradual decline of liver function from chronic liver disease. It’s not reversible. Chronic hepatitis C, chronic alcohol use disorder and metabolic dysfunction-associated steatotic liver disease (MASLD) are common causes. At this stage, extensive scarring in your liver (cirrhosis) may prevent it from working right. Scarring may also compress your portal vein (portal hypertension,) triggering a portosystemic shunt. (This would still be Type C.)

Triggering events

Chronic liver disease works slowly, and you can live with it for a long time before it really begins to affect you. Your body compensates for it until it can’t, which is when liver failure sets in. Healthcare providers have noticed that it’s often a secondary health problem or stress factor that tips the scales enough to trigger hepatic encephalopathy in people with chronic liver disease. These triggers might include:

Acute gastrointestinal bleeding.

Acute kidney failure.

Infection.

Surgery.

Constipation.

Dehydration.

Electrolyte imbalance.

Taking the wrong medication.

An alcohol binge.

Diagnosed

Several tests are used to diagnose hepatic encephalopathy.

Blood tests

A complete blood count checks your red blood cells, white blood cells, and platelets. A low red blood cell count indicates blood loss and a lack of oxygen.

Blood tests may also be used to check your blood levels of sodium, potassium, and ammonia. Having too much of these substances is a sign of impaired liver function.

Imaging tests

An imaging test, such as a CT scan or MRI, can check for bleeding in your head or abnormalities in your brain.

Liver function tests

Liver function tests check for raised enzyme levels. An increase in enzymes indicates stress on your liver or liver damage.

Tell your doctor if you have kidney disease or liver disease. The symptoms you’re experiencing along with your medical history can sometimes be enough to diagnose hepatic encephalopathy.

Treatment

Treatment options for hepatic encephalopathy depend on the severity and underlying cause of the condition.

You’ll likely need to eat less protein if eating too much protein caused the condition. Since protein is necessary for your body to function properly, a dietician or doctor can create a diet that’ll allow you to get enough protein without making your symptoms worse. High-protein foods to avoid include:

poultry

red meat

eggs

fish

Medications can also help slow the rate at which your blood absorbs toxins. Your doctor may prescribe antibiotics and lactulose (Enulose), a synthetic sugar. These medications can draw ammonia, created by intestinal bacteria from your blood, into your colon. Your body will then remove the blood from your colon.

In severe cases that cause difficulty breathing, a ventilator or oxygen mask may be necessary.

Some people with the condition may be eligible to receive a liver transplant.

Type of Doctor Department : A Hepatologist or Gastroenterologist