Diagnosing Hepatitis C
To determine whether you are infected with the hepatitis C virus (HCV), your health care provider will ask questions about your health. He or she may also try to figure out how long you have been infected with HCV. This may involve questions that seem personal. It’s important to answer honestly. You should also mention any symptoms that concern you. To test for HCV, a small sample of your blood is taken. A physical exam and certain tests help check for liver damage.
Blood tests look for substances in your blood that are linked to hepatitis C. These include:
Anti-HCV (an antibody). The body tries to fight HCV by making a substance called anti-HCV. This substance is found in the blood and indicates exposure to hepatitis C.
ALT (a liver enzyme). Blood may contain more ALT if the liver has been damaged.
HCV RNA (a part of the virus). Some tests can show pieces of HCV in infected blood and confirm that you are currently infected.
Genotype (strain of the virus). There are six HCV genotypes. A blood test can reveal which genotype you have. This will affect the type of treatment.
Looking for liver damage
During an exam, your health care provider may feel your abdomen to see if your liver is swollen or painful. Tests may also be done to check your liver for damage. These tests include:
Ultrasound, which uses painless sound waves to create a picture of the liver and can roughly stage your liver disease. Your spleen size and portal vein size should be measured with each exam. The time for the ultrasound exam should be at least 20 minutes to make sure you have the correct number of images of the liver.
CT scan, which is a type of X-ray that shows a detailed picture of the liver.
MR scan is a scan where a large magnet helps image the liver and blood vessels.
Liver biopsy, during which a needle is used to take a small sample of tissue from the liver. The sample is then viewed under a microscope to look for inflammation and the amount of scar tissue.
Checking for other infections
HCV infection can be more dangerous if you are also infected with certain other viruses. Your health care provider may test you for HIV (the virus that causes AIDS) and for other types of hepatitis (hepatitis A and B). If you have not had hepatitis A or B, you may be given vaccines (shots) to protect you from getting them in the future.