Insuficiencia hepática

What are the functions of the liver?

A healthy liver does a number of essential functions for the body. These include:

• Removing harmful substances from the body, including alcohol.

• Helping to make sure the blood clots properly.

• Storage of substances - for example, iron and glycogen (which is used to store glucose - for energy).

• Helping your body to fight against infection.

• Releasing bile, which passes into the gut (bowel) to help break down (digest) fats.

Acute liver failure is very uncommon:

• In England , there were 688 liver transplants, 28 in Scotland, 69 in Wales and 24 in Northern Ireland performed in the year April 2021 to April 2022 . The number of transplants increased by 11% from the previous year.

• The number of hospital admissions for alcohol as a contributor to liver disease has almost doubled in the last 10 years and was 75,000 people in 2019-2020.

Liver failure is caused by damage to the cells in the liver. There are many possible causes of acute liver failure. Often no cause is found but the most common causes of this type of liver failure are:

sobredosis de paracetamol

Taking too much paracetamol is a relatively common cause of acute liver failure. A paracetamol sobredosis (can be called acetaminophen overdose in some countries) can occur either by taking one large quantity of paracetamol or by taking higher than recommended doses over a few days or longer.

Medicamentos

Some prescription medicines can cause acute liver failure but this is very rare. Examples of medicines that can rarely cause acute liver failure include some antibiotics, non-steroidal anti-inflammatory drugs (NSAIDS) and some medicines used for epilepsy (anticonvulsants).

Herbal supplements

Some herbal medicines and supplements have been linked to causing liver failure.

Illegal drugs

Drugs such as ecstasy and cocaine may occasionally cause liver failure.

Infecciones

Viral hepatitis infections (for example, hepatitis B o hepatitis C) may cause liver failure. Other viruses that can cause acute liver failure include Epstein-Barr virus (causes fiebre glandular), cytomegalovirus and virus del herpes simple.

Cáncer de hígado

Cancer that either starts in the hígado or has spread to the liver from other parts of the body may cause liver failure.

Poisons (toxins)

Toxins that can cause acute liver failure include some poisonous mushrooms.

Hepatitis autoinmune

Hepatitis autoinmune is a disease in which your body's defence system (immune system) attacks your liver, causing inflammation and damaging the liver cells.

Diseases of the veins in the liver

Some diseases (for example, Budd-Chiari syndrome) can cause blockages in the veins of the liver, which can lead to acute liver failure.

Metabolic diseases

Some rare metabolic diseases may cause acute liver failure. These include hemocromatosis, alpha-1 antitrypsin deficiency, enfermedad de Wilson, fructose intolerance, galactosaemia and tyrosinaemia.

Reye's syndrome

This is a rare condition that mainly affects children and young adults. It can cause brain injury as well as liver failure. The cause is not known.

Acute liver failure can occur in a person who already has chronic liver disease when the liver damage suddenly becomes much worse. This is called acute-on-chronic liver failure.

The three most common causes of chronic liver disease in the UK are obesity, hepatitis infection and alcohol abuse that can cause alcoholic fatty liver disease. A number of chronic liver diseases gradually lead to liver cirrhosis. There is often no identified cause for the liver function suddenly becoming worse. However, known triggers include an infection or drinking alcohol. See the separate leaflet called Cirrhosis for more information about chronic liver disease and cirrhosis.

In the early stages chronic liver disease may not cause any symptoms. There may be vague symptoms such as:

• Sentirse mal (náuseas).

• Pérdida de apetito.

• Sintiéndose cansado.

• Diarrea.

More advanced chronic liver disease or acute liver failure may cause serious symptoms. These may include:

• Your skin and the whites of your eyes may become yellow (jaundice).

• Your tummy (abdomen) may become swollen because of a build-up of fluid (ascites). Your liver and spleen may also be enlarged.

• Bleeding easily and bruising without any injury.

• Your body may become very dry (dehydrated).

• The palms of your hands may become red (called liver palms).

• You may develop a slow abnormal movement of your wrist (called a liver flap).

Liver failure can also cause other symptoms due to the complications of liver failure. These include:

• Bleeding from the bowel, which may cause you to bring up (vomit) blood (haematemesis) or your stools to become very dark or black (this is caused by digested blood passing through your bowel and into your stools - it is called melaena).

• Acute liver failure, which can badly affect how our brain works and may cause you to feel drowsy and confused, and to have problems with memory and concentration, as well as having hallucinations.

• Acute liver failure, which may even cause you to go into a coma. Severe difficulty with brain functions caused by liver failure is called hepatic encephalopathy.

• The first tests are blood tests (including liver function tests such as your prothrombin time) to see how your liver is working. Blood tests will also be used to check for possible underlying causes of liver failure, such as viral hepatitis.

• Scans are arranged to look at the structure of your liver and to check for other possible causes of liver failure. These scans may include an ultrasonido, a tomografía computarizada (TC) o una escaneo de resonancia magnética (IRM).

• Some people with liver failure will need to have a liver biopsy to help find out the cause of the liver failure.

The cause of the liver failure may need specific treatment. It is essential to avoid drinking any alcohol, even if alcohol abuse isn't the cause of the liver failure. Any medicine that has caused liver failure will need to be stopped immediately.

Medicines are used to reduce the effects of liver failure on your body. These include medicines to reduce stomach acid (for example, a proton pump inhibitor). Often help with food intake is needed using a tube passed through the nose into the stomach (nasogastric tube) or a tube placed through the skin directly into the stomach (PEG feeding tube).

Other treatments may be needed to treat any complications of liver failure such as excess fluid in your brain (cerebral oedema), reduced ability of your blood to clot, brain dysfunction (hepatic encephalopathy) or acute kidney injury.

Trasplante de hígado

A liver transplant may be life-saving if a suitable donor liver graft becomes available. Various artificial liver devices have been developed and they may bridge the gap until a liver is available for transplant or until the liver failure recovery.

Liver failure may cause various complications, which are often very serious and need urgent medical attention. The complications of liver failure include:

• Reduced protection against infection.

• Fluid build-up in your brain (cerebral oedema).

• Oesophageal varices. These are dilated veins in the gullet (oesophagus) leading down into the stomach. They may cause massive bleeding and this can be life-threatening.

• Bleeding (haemorrhage) from other parts the gut (bowel).

• Lesión renal aguda.

• Severe breathing problems (respiratory failure).

How long can you live with liver failure?

Acute liver failure needs urgent assessment and treatment in order to recover. Recovery depends on the cause but has generally improved a lot in recent years - see below.

Chronic liver failure is dealt with in the Cirrosis article.

• The outlook (prognosis) depends on the cause of the liver failure, the severity of the symptoms and any complications.

• The outlook for acute liver failure (ALF) has greatly improved. In the past only 2 people in 10 with ALF survived but now more than 6 out of 10 survive as a result of improvements in intensive medical care.