Hepatitis C RNA Quantitative Test (Viral Load) with Reflex to Genotype

The test detects and counts hepatitis C virus RNA in your blood using real-time polymerase chain reaction (PCR). It reports the viral load in international units per milliliter (IU/mL) and as a log value, across a reportable range of 15 to 100,000,000 IU/mL (1.18 to 8.00 log IU/mL); below that, the result is reported as Not detected. If the viral load is 2,000 IU/mL or higher, the lab reflexes to Quest's Hepatitis C Virus RNA Genotype test (Quest code 37811), which identifies genotypes 1 to 6 and subtypes 1a and 1b.

People with a reactive hepatitis C antibody result who need to know whether the infection is current; people who have completed hepatitis C treatment and are checking for cure, which is assessed 12 weeks or more after the last dose; people previously cured or who cleared the virus on their own and have ongoing risk, since reinfection must be checked with an RNA test; and people with a possible exposure in the past six months, when antibodies may not have formed yet. If you have never been tested for hepatitis C, the hepatitis C antibody test with reflex to RNA is the usual screening test.

After a reactive antibody result, to find out whether the infection is current. After treatment, 12 weeks or later after completing therapy, to confirm cure. After a possible exposure, HCV RNA can be detected in blood within about 1 to 3 weeks, earlier than antibodies, which take about 8 to 11 weeks. For people with ongoing risk after cure, guidelines suggest an RNA test at least yearly and whenever liver enzymes rise. No fasting is needed.

Not detected means no hepatitis C RNA was found above the test's limit. After a reactive antibody test, this usually means a past infection that has cleared. Twelve weeks or more after finishing treatment, Not detected indicates cure (a sustained virologic response). A number in IU/mL means hepatitis C virus is present now, which is a current infection. If the viral load is 2,000 IU/mL or higher, a genotype result is added. A detected result should be reviewed promptly with a clinician, who will usually check liver health and test for hepatitis B before starting treatment. People cured or cleared remain at risk of reinfection. JustLabs results are informational; review them with a clinician.