From the Guidelines
Hepatitis C virus quantitative study and hepatitis C RNA testing are essentially the same diagnostic test, which measures the amount of hepatitis C viral genetic material in the blood, and should be performed using a sensitive assay with a lower limit of detection of <15 IU/ml, as recommended by 1. This test is essential for diagnosing active HCV infection, determining viral load before starting treatment, and monitoring response to antiviral therapy.
Key Points:
- The test results are typically reported in international units per milliliter (IU/mL) and can range from undetectable to millions of IU/mL.
- For patients with confirmed HCV infection, direct-acting antiviral (DAA) regimens such as Epclusa (sofosbuvir/velpatasvir), Mavyret (glecaprevir/pibrentasvir), or Harvoni (ledipasvir/sofosbuvir) are typically prescribed for 8-12 weeks depending on viral genotype, liver condition, and prior treatment history.
- RNA testing is performed before treatment to establish baseline viral load, at 4 weeks to assess early response, and 12 weeks after completing therapy to confirm sustained virologic response (SVR), which indicates cure.
- The test works by detecting and quantifying HCV RNA through polymerase chain reaction (PCR) or other nucleic acid amplification techniques, providing a direct measurement of viral replication activity in the patient, as described in 1 and 1.
Diagnostic Considerations:
- HCV RNA assays are classified as quantitative and qualitative, with quantitative assays being more sensitive and having a broader measuring range, as noted in 1 and 1.
- The HCV genotype and genotype 1 subtype (1a/1b) must be assessed prior to treatment initiation and will determine the choice of therapy, as recommended by 1.
From the Research
Hepatitis C Virus Quantitative Study vs Hepatitis C RNA
- The hepatitis C virus (HCV) is a major cause of chronic liver disease and cirrhosis, with over 71 million people infected worldwide 2.
- HCV RNA quantification is a key parameter for diagnosis and management of HCV infection, with various assays available for quantification, including real-time PCR and branched DNA-based assays 3.
- A study comparing conventional PCR with real-time PCR and branched DNA-based assays for HCV RNA quantification found significant variability in results across different genotypes, highlighting the importance of standardization 3.
- The goal of HCV therapy is to reduce all-cause mortality and liver-associated complications, with treatment considered based on genotype, extent of fibrosis or cirrhosis, prior treatment, comorbidities, and potential adverse effects 4.
- Direct-acting antiviral agents (DAAs) have revolutionized HCV treatment, with high efficacy and safety profiles, and are now recommended as first-line therapy for chronic HCV infection 5, 6.
- Quantitative HCV RNA testing is recommended for patients with confirmed HCV infection to assess the degree of liver fibrosis and determine the urgency of treatment 4.
- HCV genotype testing is also crucial in guiding treatment decisions, as different genotypes may respond differently to various DAAs 5, 6.