1. A brief summary of the liver’s functions follows, but remember there are more than 500 functions:

    • processing digested food from the intestine
    • controlling levels of fats, amino acids and glucose in the blood
    • combating infections in the body
    • clearing the blood of particles and infections including bacteria
    • neutralising and destroying drugs and toxins
    • manufacturing bile
    • storing iron, vitamins and other essential chemicals
    • breaking down food and turning it into energy
    • manufacturing, breaking down and regulating numerous hormones including sex hormones
    • making enzymes and proteins which are responsible for most chemical reactions in the body, for example those involved in blood clotting and repair of damaged tissues.
    Some of the most important functions include:

    Producing quick energy
    One of your liver’s most important functions is to break down food and convert it into energy when you need it. Carbohydrates such as bread and potatoes from our diet are broken down to glucose and stored mainly in the liver and muscles as glycogen. When energy is required in an emergency the liver rapidly converts its store of glycogen back into glucose ready for the body to use.

    Your liver also helps the body to get rid of waste products. Waste products which are not excreted by your kidneys are removed from the blood by the liver. Some of them pass into the duodenum and then into the bowel via the bile ducts.

    People with liver damage may sometimes lose the ability to control glucose concentration in the blood and need a regular supply of sugar.

    Fighting infections
    Your liver plays a vital role in fighting infections, particularly infections arising in the bowel. It does this by mobilising part of your body’s defence mechanism called the macrophage system. The liver contains over half of the body’s supply of macrophages, known as Kuppfer cells, which literally destroy any bacteria that they come into contact with.

    If the liver is damaged in any way its ability to fight infections is impaired.


The liver
If you place your right hand over the area under the ribs on the right side of your body it will just about cover the area of your liver. The liver is the largest gland, and the largest solid organ in the body, weighing some 1.8 kgs in men and 1.3 kgs in women. It holds approximately 13% (about one pint or 0.57 litres) of your total blood supply at any given moment and is estimated to have over 500 functions.

The liver is dark reddish brown in colour and is divided into two main lobes (the much larger right and the smaller left) which are further subdivided into approximately 100,000 small lobes, or lobules. About 60% of the liver is made up of liver cells called hepatocytes which absorb nutrients and detoxify and remove harmful substances from the blood. A hepatocyte has an average lifespan of 150 days. There are approximately 202,000 in every milligram of your liver tissue. Two-thirds of the body of your liver is the parenchyma, which contains the hepatocytes, and the remainder is the biliary tract. It receives its blood supply via the hepatic artery and portal vein (which transports nutrients from your intestine, or gut).














What is autoimmune hepatitis?
Autoimmune hepatitis, often referred to as AIH, is one cause of chronic hepatitis and can be, if untreated, one of the most severe forms.

For a long time AIH was known as chronic active hepatitis. AIH is just one of the causes of chronic active hepatitis but it is now recognised as a specific disease.

What causes AIH is not well understood.
It is believed the cells that do the damage are circulating blood cells known as lymphocytes. They behave as though the hepatocytes (the liver cells) are foreign and start to destroy them. This leads to chronic hepatitis which, if untreated, will progress to
cirrhosis and eventually to liver failure.


How common is autoimmune hepatitis?Fortunately AIH is relatively uncommon although it occurs in both males and females.

Between the ages of 15 and 25, it is women who are mostly affected. Around the ages of 45 and 55, both men and women are affected.



What is fatty liver disease?

There should be little or no fat in a healthy liver. For most people, carrying a little fat in the liver causes no problems. Fatty liver is the name given to a condition in which you have too much fat in your liver. This is caused by the build-up of fats called triglycerides. These are the most common fats in our bodies. They belong to a group of fatty, waxy substances called lipids that your body needs for energy and cell growth.

We get triglycerides from our diet and they are also made in the liver. The liver processes triglycerides and controls their release. It combines them with special proteins to form tiny spheres called lipoproteins which it sends into the bloodstream to circulate among the cells of your body. When this process is interrupted and the flow of triglycerides to the liver is increased, their release, or ‘secretion’, from the liver is slowed down. This is what leads to the build-up of fat in your liver cells.

Until recently fatty liver was considered rare and relatively harmless. It was not thought to progress to chronic (long-term) or serious liver disease.

Today it is one of the most common forms of liver disease and is known to lead to advanced conditions. In the majority of cases fatty liver does not cause any harm but for an increasing number of people the effects of having fat in their liver over a long period may lead to inflammation causing swelling and tenderness (hepatitis) and then to scarring (fibrosis).

In some people, this can progress to a condition known as cirrhosis, which can be life- threatening.

Clinical knowledge about fatty liver is still coming together but common risk factors are obesity, diabetes and drinking too much alcohol. While the relationship between these factors is not fully known, they can be considered triggers for progression to other types of liver disease.

If alcohol is the cause of fatty liver it is called alcoholic liver disease (ALD). This leaflet is for people worried about fatty liver that is not caused by alcohol. This is known as non alcoholic fatty liver disease (NAFLD).

What is the difference between NAFLD and NASH?
Non alcoholic fatty liver disease (NAFLD)
NAFLD is actually a term for a wide range of conditions characterised by the build-up of fat in the liver cells of people who do not drink alcohol excessively.

At one end of this range is simple fatty liver, or steatosis. This is the stage where fat is first detected in the liver cells and is generally regarded as benign (harmless).

Non alcoholic steatohepatitis (NASH) is a significant development in NAFLD. This is a more aggressive condition that may cause scarring to the liver and can progress to cirrhosis. Cirrhosis causes irreversible damage to the liver and is the most severe stage in NAFLD.

In simple terms it may be easiest to think of NAFLD as having the following stages:

1. fatty liver
2. a form of hepatitis known as non alcoholicsteatohepatitis (NASH)
3. fibrosis
4. cirrhosis

Alcohol
NAFLD is almost the same as alcoholic liver disease (ALD) and shares the same stages, with alcoholic hepatitis occurring in place of steatohepatitis (NASH).

In practical terms the only difference between the two conditions – NAFLD and ALD – is that the latter is caused by drinking too much and the former by all other causes.

NAFLD can affect a wide range of people. In general, the older you are the more chance there is that you may have the condition. NAFLD is typically seen in people aged around 50 and more commonly in men than women.

It is hard to be precise about how many people have some form of NAFLD but it is estimated that one in five people (20%) in the UK have the earliest stages of NALFD, or steatosis.

People most at risk of NAFLD are those who:


  • are obese
  • have insulin resistance, associated with diabetes
  • have hypertension (high blood pressure)
  • have hyperlipidaemia (too much cholesterol and triglyceride in their blood)
  • are taking certain drugs prescribed for other conditions
  • have been malnourished, starved or given food intravenously.
Non alcoholic steatohepatitis (NASH)
Non alcoholic steatohepatitis (NASH) is a more advanced form of NAFLD in which there is inflammation in and around the fatty liver cells. This may cause swelling of your liver and discomfort or pain around it. If you place your right hand over the lower right hand side of your ribs it will cover the area of your liver.

With intense, on-going inflammation a build up of scar tissue may form in your liver. This process is known as fibrosis, and can lead to cirrhosis. NASH is now considered to be one of the main causes of cirrhosis.

Cirrhosis is usually the result of long-term, continuous damage to the liver. This is where irregular bumps, known as nodules, replace the smooth liver tissue and the liver becomes harder. The effect of this, together with continued scarring from fibrosis, means that the liver will run out of healthy cells to support normal functions. This can lead to complete liver failure.

NASH should be distinguished from acute fatty liver disease, which may occur during pregnancy or with certain drugs or toxins (poisons). This condition is very rare and may lead rapidly to liver failure




What is cirrhosis?
Cirrhosis is the result of long-term, continuous damage to the liver and may be due to many different causes. The damage leads to scarring, known as fi brosis. Irregular bumps (nodules) replace the smooth liver tissue and the liver becomes harder. Together, the scarring and the nodules are called cirrhosis.

Cirrhosis can take many years to develop and can do so without any noticeable symptoms until the damage to the liver is very serious. The build-up of scar tissue can interfere with the fl ow of blood to your liver and stop it from functioning properly. Cirrhosis can lead to liver failure.


How common is cirrhosis?
No one knows for sure how many people in the UK have cirrhosis as most people do not know they have it until the condition is serious. However, there is no doubt that the number of people with the condition continues to increase.


Every year over 4,000 people in the UK die from cirrhosis. Around 700 people have to have a liver transplant each year to survive. people have to have a liver transplant to survive.
Who is at risk of cirrhosis?
Cirrhosis can affect anyone – men and women, young and old. People most at risk of cirrhosis:



What is hepatitis A?
Having hepatitis means that your liver has become inflamed. Hepatitis can be caused by a number of things including:


  • drinking too much
  • alcohol (the most common cause of liver damage)
  • a virus infection, such as hepatitis A
  • the body’s own immune system – a liver disease called autoimmune hepatitis
  • the side effects of some drugs and chemicals.

There are a number of viruses that infect the liver. The best known are hepatitis A, B, C, D and E. The ways in which they are spread, how they cause liver damage and the effects they can have on your health, are different. (Only hepatitis B, C and D cause chronic disease.)

Apart from hepatitis A, hepatitis B and C are the biggest problems for people in the UK.

Hepatitis A, sometimes called hep A or HAV, is a virus that is carried in the blood which infects and damages the liver. A virus is a tiny particle that needs to infect and control the cells of your body in order to live and reproduce. You can prevent illness by having a vaccination that will protect you from being infected for up to 10 years.

Where is hepatitis A common?

Hepatitis A is common in places where water supplies and sewage disposal are of a poor standard, and where personal and food hygiene standards are poor.

Southern and Eastern Europe, Africa and parts of the Middle and Far East are high-risk areas.

How is hepatitis A passed on?


Hepatitis A is passed from person to person by eating food or drinking water contaminated (infected) with the virus. The illness can spread easily within families and where people live closely together.

The virus is passed out in the bowel motions of an infected person, which is why it is important to wash your hands after going to the toilet. Drinking water can be contaminated with the virus.

Fruit, vegetables and uncooked food washed in contaminated water can cause infection, especially in hot countries. Shellfish can be infected if it comes from sea contaminated with sewage. Cooked food is safe, but can be contaminated if it has been handled by someone with the virus.

Infection is not very common in the UK. But the true number of people affected is unknown as people who only have mild symptoms may not go to a doctor.







What is hepatitis B?
Having hepatitis means that your liver has become inflamed. Hepatitis can be caused by a number of things including:


  • drinking too much alcohol (the most common cause of liver damage)
  • a virus infection, such as hepatitis B
  • the body’s own immune system – a liver disease called autoimmune hepatitis
  • the side effects of some drugs and chemicals.
There are a number of viruses that infect the liver. The best known are hepatitis A, B, C, D and E. The ways in which they are transmitted (spread or passed on), how they cause liver damage and the effects they can have on your health, are different. Only hepatitis B, C and D cause chronic or long term, disease.

Apart from hepatitis B, hepatitis A and C are the biggest problems for people in the UK.

Hepatitis B, sometimes called hep B or HBV, is a virus that is carried in the blood which infects and damages the liver. A virus is a tiny particle that needs to infect and control the cells of your body in order to live and reproduce ('replicate').

Hepatitis B is very infectious - 100 times more infectious than HIV. However, there is a simple test to find out whether you have the virus and an effective vaccine is available to protect you from it.

Where is hepatitis B common?
Hepatitis B is the most widespread form of hepatitis.
It is common in South-East Asia, the Middle and Far East, Southern Europe and Africa.

The World Health Organisation estimates that one third of the world's population has been infected at some time and that there are approximately 350 million people who are infected long term. In Europe, there are estimated to be one million people infected every year.

In the UK, approximately one in 1,000 people are thought to have the virus. In some inner-city areas with a high percentage of people from parts of the world where the virus is common, as many as one in 50 pregnant women may be infected.

How is hepatitis B passed on?
Blood
Hepatitis B is known as a 'blood-borne virus' (BBV) and is spread by blood to blood contact. Highest amounts of the virus are present in blood. Even a tiny amount of blood from someone who has the virus can pass on the infection if it gets into your bloodstream. This might be through an open wound, a cut or scratch, or from a contaminated needle.

People who use drugs and share injecting equipment have a high risk of infection. Having a tattoo or body-piercing or even acupuncture can pose a small risk if unsterile equipment is used.

The virus can also be passed on from medical and dental treatment in countries where equipment is not sterilised properly.

All blood donations in the UK are now tested for hepatitis B, but before testing was introduced it was possible to become infected by receiving blood or blood products from an infected person. In countries where blood is not tested, blood transfusions may still be a cause of infection.

The virus is able to survive outside the body for at least a week. This means that you should take care not to share iems such as a razor or toothbrush which might be contaminated with dried blood.


Sex
Hepatitis B can be transmitted by having penetrative sex without a condom with an infected person. Even oral sex can pass on the virus. Sexually active young adults who do not use condoms have a high risk of getting hepatitis B.

Other body fluids

Although it is called a blood-borne virus, hepatitis B may be present in other body fluids such as saliva, semen and vaginal fluid, particularly if these have become contaminated with blood.

Small traces have been found in sweat, tears, breast milk and urine but these fluids are not regarded as infectious.

Some people transmit hepatitis B more easily than others because they have more of the virus in their bloodstream.

Mother to baby
Hepatitis B is usually transmitted to the baby during delivery, as the baby is exposed to the mother’s blood in the birth canal. Transmission to the unborn baby does not usually occur in the uterus (before birth). Infection at birth is called ‘perinatal transmission’ and is the most common way the virus is spread globally. Vaccination of the baby at birth prevents the majority of infections.

Although small amounts of the virus have been found in breast milk, the risk from breastfeeding is not fully known and is prevented by vaccination of the new born baby.

Since April 2000, all pregnant women in the UK are tested for hepatitis B. Pregnant women with high levels of the virus in their blood may be offered additional treatment including antiviral therapy.

Work and environment
Certain jobs can put people at risk from hepatitis because they may involve contact with infectious body fluids.


  • Healthcare workers.
  • Other workers who might come into contact with body fluids including morticians, sewage workers, those in emergency services and people in the fi tness industry.
  • People who might have injuries and come into contact with others with injuries, such as people involved in contact sports or in the building industry.
  • Foster carers and people who live or work in accommodation for people with severe learning disabilities.
  • Prison staff and prison inmates are also at risk.
People who may be at increased risk because of their work or environment should be vaccinated against hepatitis B.

Travel
More than 10% of cases in the UK are thought to result from people travelling to and working in countries where there is increased risk of hepatitis B infection.

If you think you might have been exposed to hepatitis B, see your doctor immediately.

People who intend to stay in an area where hepatitis B is common, particularly if they are likely to need medical treatment such as dialysis, should get vaccinated.

It is important to remember that you are not naturally protected from infection with hepatitis B just because you are travelling to a country where you or your parents were born. Vaccination is strongly recommended for all travellers to countries where hepatitis B is common.

Hepatitis D
A few people with hepatitis B also have another virus called the delta virus or hepatitis D. This virus needs the hepatitis B virus to survive, which means that it is only possible to have hepatitis D if you have hepatitis B. Hepatitis D is also passed on in blood and is most common in injecting drug users, though it is not common in the UK overall. Being infected with both viruses can lead to more serious liver disease.

There is a separate publication on Hepatitis D available containing further information





Hepatitis: what does it mean?
Having hepatitis means that your liver has become inflamed. Hepatitis can be caused by a number of things including:

  • drinking too much
  • alcohol (the most common cause of liver damage)
  • a virus infection, such as hepatitis C
  • the body’s own immune system – a liver disease called autoimmune hepatitis
  • the side effects of some drugs and chemicals.
There are a number of viruses that infect the liver. The best known are hepatitis A, B, C, D and E. The ways in which they are spread, how they cause liver damage and the effects they can have on your health, are different. (Only hepatitis B, C and D cause chronic disease).
What is hepatitis C?
Hepatitis C, sometimes called hep C or HCV, is a virus that is carried in the blood which infects and damages the liver.

A virus is a tiny particle that needs to infect and control the cells of your body in order to live and reproduce. The hepatitis C virus infects the cells in your liver, causing inflammation (swelling and tenderness) and fibrosis. In people with chronic (long-term) hepatitis C infection, inflammation and fibrosis continue to spread. Over time, usually many years, this can lead to cirrhosis.
What happens if I'm infected with hepatitis C?
People react differently to the hepatitis C virus. As the hepatitis C virus can take many years to make itself known, you could be living with it for many years without realising it. The hepatitis C virus disappears in one in four people with no lasting damage. However, up to one in three people with the virus are likely to develop cirrhosis – a serious liver disease – within 20 to 30 years. Other people will live with mild liver problems.








What are hepatitis D and E?
Although they sit together in the hepatitis alphabet, hepatitis D and E are in fact quite different.

Hepatitis D
Hepatitis D (HDV), sometimes referred to as the delta virus or delta agent, is an incomplete virus that requires the presence of the hepatitis B virus to survive in your body. This means that it is only possible to have hepatitis D if you have hepatitis B.

You can acquire hepatitis D infection at the same time you are infected with hepatitis B. This is called ‘co-infection’. If you are infected in this way, acute hepatitis will develop following an incubation period of up to three months. This is the time it takes between infection and the appearance of first symptoms.

If you already have chronic hepatitis B and become infected with hepatitis D, this is known as ‘superinfection’. While the combination of hepatitis D and hepatitis B can be more serious than hepatitis B by itself, superinfection is more likely to cause severe chronic hepatitis and cirrhosis.

Around 5% of people with hepatitis B also have hepatitis D.

Hepatitis D is seen mainly in central Africa, the Middle East and central South America. Infection rates in most of Europe and the United States are low.

Three particular forms of the virus, called genotypes, are currently known:


  • type 1, the most common form of disease in most areas of the world
  • type 2, a less severe form found more commonly in Taiwan
  • type 3, a more severe form found in South America.
Hepatitis D affects approximately 15 million people worldwide.

Hepatitis E

Hepatitis E (HEV) is also caused by a virus. Outbreaks have now been recorded from many areas of the world. It is most common in parts of South Asia, Africa and Central America that are associated with poor sanitation. Hepatitis E is very rare in the UK but it is now accepted that the virus is also transmitted here.

Hepatitis E has an average incubation period of four to six weeks. The disease is generally mild in its effect unless you have pre-existing liver disease and lasts only a couple of weeks. There is no chronic infection caused by hepatitis E.

It has now been classified into four genotypes:
  • type 1, most commonly found in Asia and Africa
  • type 2, found in Mexico
  • type 3, found in USA and Europe only
  • type 4, found in China, Taiwan and Japan.
In the UK, hepatitis E diagnosed in people who have travelled abroad is usually genotype 1. Overall, hepatitis E tends to affect people aged between 15 and 40 more than other groups.

Among pregnant women there is a risk of the virus causing a severe and rapidly occurring form of hepatitis that can lead to liver failure. This is called acute fulminant hepatitis and is becoming a major health concern in countries where hepatitis E more commonly occurs.

How are hepatitis D and E spread?
Hepatitis D, like hepatitis B and C, is called a ‘bloodborne virus’ (BBV) indicating that it is spread by blood to blood contact. This means an infected person can pass on or ‘transmit’ the virus to you if their blood is able to enter your bloodstream. This can happen through an open wound, a cut or scratch or from a contaminated needle. Even dried blood can remain infectious for more than a week.

In the UK, people who share drug injecting equipment (intravenous drug users or IDUs) are most likely to be infected by hepatitis D. Having a tattoo or body-piercing or even acupuncture can also pose a small risk if unsterile equipment is used.

The virus can be transmitted from medical and dental treatment in countries where equipment is not sterilised properly. If you have a blood disorder or require blood transfusions, you may be at risk from exposure to unscreened blood products.

There are two other main ways the virus is transmitted:


  • Having penetrative sex with an infected person without wearing a condom.
  • From an infected mother to her baby during birth, when the baby is exposed to the mother’s blood in the birth canal. This is called ‘perinatal transmission’.
The hepatitis E virus is spread in a way similar to hepatitis A, known as ‘faecal-oral’. This means that the virus is passed out in bowel motions (faeces) and finds its way into the mouth (orally). This can occur when you drink from a contaminated water supply or eat food that has been touched by contaminated hands.

Widespread outbreaks of the virus can occur frequently or constantly in overseas countries (referred to as ‘endemic areas’) where water supplies are contaminated with sewage after monsoons and flooding.

Unlike hepatitis B, C or D the hepatitis E virus is not transmitted through blood, needles, or other body fluids or through sexual contact.



What is a liver transplant?

A liver transplant is an operation where your diseased liver is removed and replaced with a healthy donor human liver. Although liver transplants are now quite common, the operation is not undertaken lightly. It is a major operation and the body will always see the 'new' liver as a foreign agent and will try to destroy it. This means that if you have a liver transplant you will have to take medication for the rest of your life in order to stop your body rejecting the donor liver.

Why do I need a liver transplant?

You may need a liver transplant if your liver is damaged to the point where it is unable to repair itself and is likely to fail completely. Your doctor may advise you to have a transplant when it is thought this will either dramatically improve your quality of life or that, without a transplant, you will die.

The main causes of severe liver damage that lead to people needing a transplant are:

  • cirrhosis
  • hepatitis
  • metabolic conditions (problems with the physical and chemical processes that take place inside your liver to keep you alive)
  • paracetamol poisoning.
How will I benefit from a transplant?

By the time you discover you need a transplant your liver might begin to fail and your quality of life may be very poor. You may have experienced the following symptoms:

  • loss of appetite
  • generally feeling unwell and being tired
    all the time
  • feeling sick and being sick
  • very itchy skin
  • loss of weight and muscle wasting
  • enlarged and tender liver (you may feel very
    tender below your right ribs)
  • increased sensitivity to alcohol and drugs
    (medical and recreational)
  • yellowing of the skin and whites of the eyes
    (jaundice)
  • swelling of the lower abdomen, or tummy
    (ascites), or the legs (peripheral oedema)
  • fever with high temperatures and shivers, often caused by an infection
  • vomiting blood
  • dark black tarry stools (faeces) or pale stools, associated with cholestatic disease
  • periods of mental confusion.
If your transplant is successful, not only should
these problems clear up but you will have a longer
life expectancy.