Diagnosing HCV

Testing for HCV is not routinely done, so you may have to request a test from your physician. It is recommended that you use the same laboratory for all of your tests, since result ranges and accuracy can vary from lab to lab. Keep copies of your lab and biopsy results for future reference. The tests below can help determine whether you are infected with HCV as well as the state of disease progression.

HCV Antibody Tests

• ELISA II is a simple blood test that can detect HCV antibodies.
• RIBA is a second antibody test that may be performed after an ELISA II test to confirm antibody positivity.

Viral Load Tests

Viral load tests measure the amount of HCV circulating in the blood. The HCV viral load is expressed in either copies per milliliter of blood or in a standard unit of measurement called International Units. There are three different types of viral load tests-HCV RNA PCR assay, RNA branched-chain DNA (bDNA) assay and the transcription mediated amplification or TMA assay. The HCV RNA branched-chain DNA (bDNA) assay is the least expensive but also the least sensitive. Viral load tests are used to confirm active infection, as a predictor of medical treatment response and, during medical treatment, to measure how well your medication is working against the virus. An association between viral load and disease progression has not been established.

Genotype tests

Genotype tests are used to determine which type(s) of HCV you have. This information is useful for making treatment decisions such as which medications to use and how long treatment should last.

Liver Enzyme/ Function Tests

Liver enzyme/function tests measures certain functions of the liver. The most common measurements are alanine aminotransferase (ALT, formerly known as SGPT) and aspartate aminotransferase (AST, formerly known as SGOT). ALT and AST are enzymes that are released into the blood when the liver is damaged. They are often elevated in people with chronic HCV infection. Many people with HCV have mild to moderate elevations of these two enzymes, which are often the first indication that they have HCV. Other measurements include alkaline phosphatase (ALK) and gamma-glutamyl transpeptidase (GGT) levels. Abnormal levels may indicate cirrhosis and/or bile duct blockage, as well as other abnormalities. In addition, your doctor may measure prothrombin time (an indication of blood clotting speed) and bilirubin levels. Bilirubin is a pigment that is often present in the blood of people with liver inflammation; high bilirubin levels result in jaundice. Many factors such as use of medications and alcohol may cause abnormal lab results. Before drawing your own conclusions, check with a healthcare practitioner.

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