Hepatitis C - Diagnosing hepatitis C

If you think you may have been exposed to hepatitis C, taking a test will put your mind at rest or, if the test is positive, allow you to start treatment early.

Your GP, sexual health clinic, GUM (genitourinary medicine) clinic or drug treatment service all offer testing for hepatitis C.

Find your nearest sexual health service.

Testing for hepatitis C

Hepatitis C is diagnosed with two blood tests:

• the antibody test
• the PCR test

The antibody test

This blood test determines whether you have ever been exposed to the hepatitis C virus by testing for the presence of antibodies to the virus.

Antibodies are proteins produced by your immune system to fight invading particles, such as viruses, when they enter your bloodstream.

The test will not show a positive reaction for some months after infection. This is because your body takes time to make these antibodies.

If the antibody test is negative but you have had symptoms, or you have been exposed to hepatitis C, you may be advised to have the test again.

A positive test (showing antibodies) indicates that you have been infected at some stage. It does not necessarily mean you are currently infected, as you may have since cleared the virus from your body.

The only way to tell if you are currently infected is to have a second blood test, called a PCR test.

The PCR test

This blood test checks if the virus is still present by detecting whether it is reproducing inside your body.

A positive test – often reported as "detectable" or "detected" – means that your body has not fought off the virus, and the infection has progressed to a chronic (long-term) stage.

Test results usually come back within two weeks.

It is recommended that the following groups of people should be tested for hepatitis C:

• ex-drug users
• current drug users
• people who received blood transfusions before September 1991
• recipients of organ or tissue transplants before 1992, or in countries where hepatitis C is common
• babies and children whose mothers have hepatitis C
• anyone accidentally exposed to the virus (needlestick or splash injury), such as health workers
• people who have received a tattoo or piercing where equipment may not have been properly sterilised
• sexual partners of people with hepatitis C
• people who have lived or had medical treatment in parts of the world where hepatitis C is more common – high risk areas include North Africa, the Middle East and Central and East Asia

If you continue to engage in high-risk activities, such as injecting drugs frequently, then regular testing may be recommended. Your GP will be able to advise you.

Other tests and referral

If you have the virus, your GP may recommend other tests to check for damage to your liver. These include liver function tests, which measure certain enzymes and proteins in your bloodstream that indicate whether your liver is damaged or severely inflamed.

Your GP will also refer you to a specialist centre for an assessment and to discuss treatment. The specialist will ask for more checks to assess the extent of liver damage, including blood tests and ultrasound scans of the liver and abdomen. Many centres are now using a fibroscan (a type of ultrasound) to check for liver damage and scarring.

The amount of liver damage can also be assessed by taking a sample of your liver tissue for examination. This is called a liver biopsy and involves passing a hollow fine needle through the skin into your liver. The cells are then examined under a microscope to assess the amount of liver damage and cirrhosis (scarring). The specialist will advise you about the need for a liver biopsy. However, a biopsy is not always necessary before treatment.