Viral hepatitis - Symptoms, Causes and Treatments
"Hepatitis" simply means that the liver is inflamed.
Hepatitis can be caused by various things. Some substances (like excessive alcohol and certain medications) are toxic to the liver. There are also a number of infectious causes of hepatitis. Here we look at the most important of these, the hepatitis viruses.
When a hepatitis virus reaches the liver, it infects the liver cells and multiplies inside them. The body's immune system attempts to destroy these cells. This attack by white blood cells causes liver-cell damage and inflammation. Chronic (long-standing) viral hepatitis can cause irreversible liver damage.
Types of viral hepatitis
Three viruses are very significant causes of hepatitis. Hepatitis A, B and C viruses are unrelated to one another, but all target the liver.
Hepatitis A is an acute (short-term but quite severe) infection of the liver. The virus is found in the faeces of an infected person, and reaches the liver after infecting the gut. It is usually acquired from hands soiled after using the toilet or changing a nappy, or by swallowing water or food contaminated by human faeces. Uncooked shellfish and raw vegetables contaminated by sewage can also be a route of infection, as can sexual contact with an infected person.
Hepatitis A occurs worldwide, commonly in undeveloped parts where it is mostly acquired by young children due to poor sanitation. In developed countries, with good sanitation and hygiene, exposure is low. In Australia, a few hundred cases of hepatitis A are reported yearly, and infection is most likely in particular situations:
- At child day-care centres and pre-schools
- Among men who have sex with men
- Among intravenous drug users
- At residential facilities for the intellectually disabled
- Among travellers to less developed countries where the infection is common
Hepatitis B is the most common liver infection in the world, with 350 - 400 million people with chronic disease, mostly in the Asia-Pacific region. People are often initially unaware they have been infected, but eventually hepatitis B can lead to cirrhosis (scarring of the liver), liver cancer or liver failure if not diagnosed and managed. In Australia, more than 200,000 people are chronically infected with hepatitis B, and the chronic infection is responsible for several hundred deaths annually.
Most people with chronic hepatitis B in Australia were born elsewhere, largely in the Asia-Pacific region. Immigrants from the Mediterranean, Eastern Europe, Africa and Latin America also have high rates of infection. Other groups at higher risk of hepatitis B include indigenous Australians, people participating in high-risk sexual activity and intravenous drug users.
Hepatitis B is highly infectious, and is mostly spread by close contact with an infected person, via the exchange of minute quantities of blood from tiny grazes or cuts. This might occur through:
- Rough play among children
- Sharing toothbrushes or razors
- Direct contact with blood, e.g. a bleeding wound
- Tattooing or scarification with unsterile implements
- Intravenous drug abusers sharing needles and syringes
- Between patients and staff in hospital settings, e.g. haemodialysis units
- Potentially, by blood transfusion. Since all blood donations are screened for hepatitis B and C, this risk is low.
- Hepatitis B can be passed from an infected mother to her baby.
Hepatitis C is also spread through blood-to-blood contact, but is far less infectious than hepatitis B. Around 150 million people worldwide are chronically infected with hepatitis C. In Australia, it is the primary cause of liver transplants and has exceeded HIV as the number-one cause of death from a blood-borne virus. It affects over 225,000 Australians. However, the number of new cases is declining.
Hepatitis C is strongly linked to high-risk groups for blood-borne diseases. Approximately 83% of Australian infections result from unsafe intravenous drug use. Five percent of infections occurred through contaminated blood transfusions (prior to 1990), and the remaining cases were caused by unsterile tattooing or body piercing; unsterile medical procedures or vaccinations; needle-stick injuries; or some other exposure to infected blood or blood products. Hepatitis C can also be passed from infected mother to baby.
There are at least two more important hepatitis viruses, hepatitis D and E. Neither is common in Australia. Hepatitis D, also called “delta virus”, is only found along with hepatitis B and it cannot survive independently. It can worsen the effects of hepatitis B. Hepatitis E is spread in a similar way to hepatitis A, though generally in waterborne outbreaks. It is found most commonly in developing countries.
Occasionally, viruses that are not true hepatitis viruses can cause liver inflammation. Patients might have a mild hepatitis during glandular fever or the similar illness caused by cytomegalovirus. Extremely rarely, herpes simplex virus can cause an aggressive form of hepatitis that is usually rapidly fatal.
Many people have no symptoms when they get infected with hepatitis. Where symptoms do occur, they are often slow to appear. After infection, hepatitis A takes about four weeks to cause symptoms, hepatitis B about three months, and hepatitis C about two months.
Early symptoms may include:
- Loss of interest in food, especially fatty food
- Distaste for cigarettes (if you are a smoker)
- Loss of ability to drink alcohol
- Feeling unwell
- Muscle aches
- In the case of hepatitis B, joint pains and rash can occur
In established disease, symptoms include:
- Nausea, with or without vomiting
- Discomfort or pain in the right upper abdomen (where the liver is located)
- Urine that is dark reddish-brown
- Faeces unusually pale in colour
- A yellowish tinge to the whites of the eyes and skin
The following are potentially serious symptoms that require medical attention:
- Persistent vomiting for longer than six hours
- Extreme drowsiness, confusion or restlessness
- Unusual bruising or bleeding
- Jaundice continuing for longer than three weeks
Liver inflammation involves swelling. This causes blockage of the bile ducts; the bile that should flow into the gall bladder is trapped in the liver. Since it cannot escape, the yellow-green bile becomes absorbed into the bloodstream and circulates to the skin and eyes, causing the yellow discoloration known as "jaundice". Liver swelling is also what causes pain in the abdomen.
Symptoms can last for a week or two, or months, depending on the virus and response of the person infected. In general, adults have worse symptoms that last longer. Pregnant women are at slightly increased risk of severe hepatitis A.
However, many people, especially children, are not aware that they have ever had hepatitis or even that they have become chronically infected. They may only discover this through a blood test.
The most frequent complication of hepatitis B and C is that the virus is not cleared by the immune system, but persists in the liver long-term. If it persists after six months, this is called “chronic viral hepatitis”. Around 10% of people with hepatitis B, and about 80% with hepatitis C, will develop chronic hepatitis. Hepatitis A does not become chronic.
Most chronically infected people have no or few symptoms; they may be carriers, and can transmit their infection to others. Some, however, will have "chronic active hepatitis", which means the inflammation is marked and will cause ongoing symptoms, and will ultimately result in significant liver damage.
Liver damage will progress quickly or slowly, depending on how active the infection and inflammation is. On average, serious damage from chronic hepatitis takes about 20 years to develop. The end result is cirrhosis. A cirrhotic liver has undergone many cycles of scarring and regrowth, and is lumpy, distorted, poorly functioning and prone to cancer.
About 1% of people who get viral hepatitis suffer severe liver damage at the outset. Much of the liver can be destroyed and the person goes into liver failure. Signs that this is occurring include drowsiness that progresses to coma, and bleeding, usually in the gut. This condition requires urgent hospitalisation.
Hepatitis B and C can be complicated by kidney disease. This is probably due to clumps of virus and anti-virus antibodies deposited in the kidney filtration system. In children, this may cause "puffiness" of the face and limbs. In adults, a common sign is blood in the urine.
Hepatitis B and C can be transmitted from infected mother to baby. This can happen while the baby is in utero, or, more often, during delivery. If no preventative measures are taken, the risk of transfer of hepatitis B to the baby is high (around 90%); it is much lower with hepatitis C (around 5%). Because of the immaturity of the immune system in newborn babies, most of these infections become chronic. Fortunately, with hepatitis B, the chance of transmission is much reduced if immunoglobulin and vaccine are given to the baby at birth.
Anyone experiencing hepatitis symptoms, or concerned they have been exposed to a hepatitis virus, should visit a doctor. A healthcare professional will often be able to detect if the liver is enlarged and tender during examination.
Laboratory diagnosis of hepatitis A and B requires blood tests. These tests look for markers of the virus in the blood, such as antigens (a foreign substance in the body, such as a virus) and antibodies – the proteins that the immune system makes in response to a vaccine or infection. With hepatitis B, additional tests can analyse whether this is a recent or chronic infection, and how active the virus is.
An early or recent hepatitis C infection may not be detected so readily. The usual test only becomes positive when antibodies are produced by the immune system, several weeks or months into the illness. A specialised "PCR" test for hepatitis C virus may be required in some cases to show current infection.
The liver also produces blood proteins such as albumin and clotting factors, and levels of these proteins may be low in severe or long-standing hepatitis. Tests used to check how well the liver is working may include:
- Liver Function Tests (LFTs) that show if the liver has been damaged. Abnormalities may also indicate acute liver infection.
- Liver biopsy involves the removal of a small piece of tissue from the liver. This is examined under a microscope to look for inflammation or damage.
- Alpha-fetoprotein is a blood test that may detect liver cancer.
If the person with hepatitis feels unwell, bed rest is advised. Otherwise, if there is no fever, normal activities can be continued. A temperature higher than 39 degrees Celsius can be treated with paracetamol. This drug should be used with caution because it is usually processed by the liver, and this ability will be impaired in a person with viral hepatitis.
A person with hepatitis will probably be inclined to avoid fatty foods. Otherwise, a regular diet can be followed. If appetite is poor, fruit juice and other liquids should be encouraged. Avoid alcohol.
There is no effective treatment available for acute hepatitis (a new infection). Recovery is dependent on the person's immune response.
Even if a person appears to make a full recovery, in the case of hepatitis B and C, follow-up blood tests should be done to show whether the infection has been cleared or whether it has persisted as a chronic infection.
There are limited possibilities for treating chronic hepatitis. People with no liver damage need no treatment, but should be monitored with regular liver function tests. For those with liver damage, a few drug treatments are available. Drugs that are sometimes successful for managing chronic viral hepatitis include interferon-alpha, anti-viral medications such as lamivudine, adefovir, entecavir and tenofovir (for hepatitis B) and ribavirin (for hepatitis C). Boceprevir and telaprevir are two new medications recently added to the treatment regime for hepatitis C in Australia.
Hepatitis complications might require medical treatment in hospital. A liver transplant may be required to save a person with end-stage liver damage.
Hepatitis A is prevented by good sanitation, clean tap water and basic hygiene, e.g. hand washing after using the toilet or changing a nappy, and before preparing food. (A person with hepatitis A should not prepare food for others.)
The hepatitis A virus is in the faeces of an infected person from two weeks before symptoms begin to about a week afterwards. If your child has hepatitis A, their school should be notified. However, they can return to school, and adults to work, one week after onset of symptoms, as they are no longer significantly infectious.
With hepatitis B or C, which take several months to clear from the blood, a person will probably be well enough to return to normal activities while still infectious. They should avoid any contact with others that creates an infection risk. Normal office or school activities (except for contact sports) do not pose a risk to others. Follow-up blood tests will show when a person is no longer infectious.
Anti-hepatitis immunoglobulins are antibodies harvested from the donated blood of people immune to the hepatitis virus. This can protect people who have been exposed to hepatitis A or B and have not been vaccinated in the past. The immunoglobulin, given by injection, can provide "instant immunity", which lasts approximately six weeks. Immunoglobulin is not effective if given too late after exposure.
A common reason for the use of hepatitis A immunoglobulin is to protect staff, parents and children in a pre-school outbreak. Hepatitis B immunoglobulin can be used following any accidental exposure, and to protect newborn babies when the mother is infected. Immunoglobulin and a first dose of hepatitis A or B vaccine can be given simultaneously.
For hepatitis C, immunoglobulin is not available.
A hepatitis A vaccine is available, and is effective in preventing infection in about 95% of people. The vaccine is given by injection in two doses; duration of immunity appears to be at least 10 years. Pregnant women should delay being immunised against hepatitis A until after pregnancy, unless they are at great risk of infection.
Hepatitis A vaccination is recommended for:
- Travellers to developing countries
- Aboriginal and Torres Strait Islander children between 18 months and six years in north Queensland
- Workers in rural and remote indigenous communities
- Child day-care and pre-school staff and carers
- The intellectually disabled and their carers
- Healthcare workers in rural, remote indigenous communities, and those employed in paediatric, intensive-care and emergency units that provide for Aboriginal and Torres Strait Islander children
- Sewage workers
- Men who have sex with men
- Intravenous drug users
- Patients with chronic liver disease
- Haemophiliacs who may receive blood products
Hepatitis B can be prevented with a safe, effective vaccine. It is recommended that the following groups, in particular, be vaccinated against hepatitis B:
- Babies, young children and adolescents between 10 and 13
- Household and/or sexual contacts of people with hepatitis B
- People on haemodialysis, with HIV or otherwise weakened immune systems
- Intravenous drug users
- Recipients of certain blood products
- Individuals with chronic liver disease and/or hepatitis C
- Residents and staff of institutions for people with intellectual disabilities
- People adopting children from overseas
- Liver transplant recipients
- Inmates and staff at long-term correctional facilities
- Healthcare workers, dentists, embalmers
- Tattooists, body piercers
- Police, soldiers, emergency-services staff
- Travellers to high-risk regions
- Staff of child day-care centres
- People playing contact sport
People at high risk of exposure to both hepatitis A and hepatitis B should consider receiving the combined hepatitis A/hepatitis B vaccine.
No vaccine for hepatitis C has been developed, but people with hepatitis C should be vaccinated against both hepatitis A and hepatitis B.
A post-vaccination blood test, to assess if the vaccine has been effective, is recommended for people at significant occupational risk (e.g. healthcare workers); people at risk of severe or complicated disease (e.g. people with pre-existing liver disease, adults with weakened immune systems); and those in whom a poor response to the vaccination is expected.
References: Hepatitis Australia Media Release, 19 February 2013; The Kirby Institute (2012), HIV, viral hepatitis and sexually transmissible infections in Australia Annual Surveillance Report 2012; National Health & Medical Research Council, The Australian Immunisation Handbook 2008; World Health Organisation (2008), Hepatitis B Factsheet; (2012), Hepatitis C Fact Sheet.
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