Hepatic encephalopathy

How does hepatic encephalopathy develop?

Cause of hepatic encephalopathy (also: postage systemic encephalopathy) is a serious dysfunction of the liver. One of the most important tasks of the organ is to reduce toxins in the body. However, sometimes the liver is so damaged that it can not cope with this task – for example, when liver cirrhosis develops as a result of years of alcohol abuse or hepatitis. The liver tissue is then largely knotty scarred and loses its function.

Rising pollutant concentrations in the blood

If the liver is no longer able to break down toxins into harmless components, the concentration of pollutants in the blood increases. This has serious consequences for the whole body, especially the central nervous system (CNS), especially the brain cells. Various substances are involved – especially ammonia, a degradation product of various amino acids (building blocks of proteins).

Normally, the liver processes ammonia into non-toxic urea, which is excreted. If this mechanism is disturbed, more and more ammonia gets into the brain and causes certain brain cells – the so-called astrocytes – to swell up. The intracranial pressure rises. Thus, a liver failure ultimately causes cerebral edema.

Hepatic encephalopathy: trigger

Acute liver failure due to viral infection or intoxication can also trigger acute hepatic encephalopathy. In this case, the liver functions are destroyed within a few days.

Most of the time, however, the cause is a chronic liver disease, to which suddenly additional factors are added. In such cases does not develop abruptly, but slowly and gradually. This includes:

• Bleeding in the gastrointestinal area
• high protein food
• Infections that lead to increased protein utilization
• Diarrhea, vomiting or laxatives
• certain medications (such as sedatives)

Sometimes doctors treat cirrhosis with a so-called portosystemic shunt, an artificial compound in the vascular system, which ensures that the blood from the intestine, stomach and spleen is no longer collected through the damaged liver. This can be useful, for example, prior to liver transplantation. One possible side effect of this procedure is hepatic encephalopathy, as the blood is no longer filtered.

Hepatic encephalopathy: symptoms and stages

The swollen astrocytes change the concentration of different messenger substances in the brain, and the nerve cells can no longer communicate properly. Therefore, hepatic encephalopathy involves various neurological symptoms that are classified into four stages and a pre-stage depending on severity.

Pre-stage (minimal hepatic encephalopathy)

In many cases, the first stage is preceded by a phase in which hepatic encephalopathy is barely symptomatic. This is also called minimal hepatic encephalopathy. Mostly only close relatives notice that something is wrong with the person concerned. The patients are sleepy and show losses in

• concentration
• Short-term memory
• visual-spatial perception
• information processing
• fine motor skills

Neurologically, nothing can be ascertained here. With various psychometric tests, such as numbers or drawing exercises, one can uncover this stage.

Caution: Already there is an increased risk of accidents in traffic!

Hepatic encephalopathy: stage 1

In the first stage, the symptoms are still relatively easy.

• sleep disorders
• mood swings
• euphoria
• slight confusion
• difficulty concentrating
• eyes flutter

Hepatic encephalopathy: stage 2

By means of electroencephalography (EEG), it is also possible to record, from the second stage, changes in the brain waves that indicate hepatic encephalopathy. Otherwise, increase the symptoms from stage 1 as well

• personality changes
• disorientation
• fatigue
• memory problems
• changed facial expressions (grimacing)
• rough shaking of the hands (“flapping tremor”)

Hepatic encephalopathy: stage 3

The poisoning is well advanced, the symptoms are serious.

• Patient sleeps most of the time
• strong disorientation
• Flapping tremor
• indistinct language

Hepatic encephalopathy: stage 4

The condition of the patient worsens to unconsciousness.

• Liver coma (Hepatic coma)
• Patient can not be woken up, but still responds to stimuli

While in acute liver failure the affected person usually lives through the individual stages very quickly and may fall into a coma within days, hepatic encephalopathy progresses slowly and gradually in people with chronic liver failure. Most of the time there is no pronounced cerebral edema during the course of the disease.

Especially in the elderly you will find chronic courses. In their “ground state”, they usually show only mild neuropsychiatric symptoms. In between, acute phases with more pronounced symptoms occur.

Hepatic encephalopathy: treatment

The treatment of hepatic encephalopathy focuses on two factors: the elimination of triggers and the reduction of ammonia formation.

Elimination of triggering factors

• Breastfeeding of a gastrointestinal hemorrhage
• Discontinuation of dehydrating agents
• Narrowing of a liver shunt

Reduction of ammonia load

• Lactulose and lacitol increase acidity in the gut, which reduces the absorption of ammonia from the gut
• Taking an antibiotic that weakens the ammonia-producing bacteria.
• At least temporarily low-protein diet, especially meat and eggs. because its processing produces ammonia.

Further measures

The administration of the following substances can additionally improve the condition:

• zinc prevents cell damage in the liver and helps to regenerate it.
• Ornithine aspartate accelerates the urea cycle, thereby lowering the ammonia content and thus improving brain function.
• Branched-chain amino acids prevent the body from breaking down its own protein in order to compensate for its deficiency. This produces ammonia.