Diagnosis

If you have engaged in any of the higher risk activities identified earlier in this booklet, you need to be tested. Testing is also advised if you have engaged in any of the lower risk activities, or think you may have been exposed to the blood of an HCV infected person. If you regularly use a factor concentrate (recombinant or plasma-derived), it is standard to be tested once a year.

Suspecting you may be infected with HCV but not knowing for sure leaves you at a disadvantage. If the test detects the presence of HCV in your body, it enables you to do the following:

• Understand the extent of liver damage by discussing your test results with your health care provider (HCP).
• Consider early treatment.
• Take precautions not only to prevent the spread of the virus but also to protect yourself from being re-infected with a different genotype of HCV.
• Obtain vaccination against hepatitis A (HAV) and hepatitis B (HBV). These viruses can worsen liver disease if you already have HCV. Obtaining the flu vaccine and the pneumonia vaccine is also wise. (Your local Public Health Clinic may offer one or more of these vaccines for free).
• Monitor the progress of the infection in order to catch liver problems early.
• Learn more about HCV and make appropriate lifestyle changes, such as: choosing to consume less alcohol, improving eating habits, and exercising regularly.

The only way to know if you have been infected by HCV is to get tested. Different blood tests will test for different aspects of HCV. The most important tests are as follows.


Tests to determine whether you have HCV

1. Anti-HCV (HCV antibody test)
Antibodies are proteins made by a person’s immune cells in response to a viral infection or a vaccination. Antibodies circulate in the blood and are usually present lifelong. The anti-HCV test determines the presence of antibodies to HCV and thus indicates previous exposure to the virus. It does not measure the virus itself.

NOTE: Because it may take up to three months after exposure for the body to develop antibodies to HCV, there may be a false negative test result during this time period. A person with a poor or suppressed immune system may have a false negative test result because the body is unable to make antibodies. A person with a poor immune system should therefore be tested for HCV using the nucleic acid PCR test.

a) Qualitative: This test is the most sensitive and will simply detect the presence or absence of the virus in the blood. The result will be either positive (meaning the virus is present) or negative (meaning the virus cannot be detected).

b) Quantitative: This test measures the amount of virus in the blood (also known as the viral load). The result is a number value usually expressed as “copies.”

NOTE: If the results come back anti-HCV positive but HCVRNA negative, it means that you have been exposed to HCV, but your body eliminated the virus from your body.



Test to determine whether HCV is active

Serum liver enzyme tests
Enzymes supply the energy for cells to perform their normal function. Normally, only small amounts of enzymes leak out of the liver cells and into the blood stream. However, if the liver cells are inflamed, more enzymes will leak out and their levels in the blood will increase. The common enzymes that are measured are aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Having consistently normal returns from liver enzyme tests is an encouraging sign. However, damage to the liver may still be happening, so it is recommended that you also have a liver function test (see below).

NOTE: Raised enzyme levels (including AST and ALT) can be caused by conditions other than HCV, such as metabolic liver disease, fatty liver, or liver disease induced by alcohol, street drugs or certain medications.



Tests to determine whether the liver is being affected by HCV

1. Liver function tests
These tests measure liver function by quantifying some of the proteins manufactured by the liver, such as albumin and blood clotting factors (INR), platelets, or the products excreted by the liver, such as bilirubin (bile).

2. Liver biopsy
A percutaneous biopsy removes a small sample of your liver (via a needle inserted through the skin) for analysis. It is the most accurate way to assess the amount of inflammation and the degree of scarring (fibrosis), including cirrhosis. A biopsy makes it possible to grade the inflammation and stage the fibrosis.

a) Inflammation Graded on a scale from 0-4 (higher number = greater inflammation)

b) Fibrosis Staged on a scale from 1-4 (higher number = greater fibrosis, or stage 4 = cirrhosis).

c) Fat and iron There are many other features seen on a liver biopsy including the amount of fat and iron in the liver.

NOTE: People with hemophilia or a related bleeding disorder do not normally choose to have a biopsy because of the greater possibility of bleeding, but there are situations in which one might have a biopsy despite this increased risk. A person with mild hemophilia may have a standard biopsy and take the precaution of coverage with clotting factor. A person with severe hemophilia would almost certainly have a transfemoral (accessing the liver across or through the main artery of the thigh) or transjugular (accessing the liver across or through the main vein in the neck) biopsy. If bleeding occurs, it backs into the vein. People having an inhibitor to factor concentrate should take the increased risk of bleeding into consideration as it may add an unacceptable level of risk.

NOTE: There are other methods that will indirectly indicate advanced liver disease. Low platelet counts, splenomegaly (enlarged spleen), or signs of portal hypertension (increased pressure inside the veins that bring blood from the intestines to the liver) are examples. Imaging the liver with ultrasonic waves (ultrasound) or by computed tomography (CT scan) may also suggest the presence of cirrhosis.