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Hepatitis C is a common cause of viral hepatitis and can progress to chronic hepatitis, which can result in liver failure, cirrhosis, or hepatocellular carcinoma if undiagnosed and untreated. Before initiating treatment with select NS5A inhibitors, hepatitis C virus (HCV) genotype and subtype testing is recommended. This test sequences NS5A codons 20-101 for HCV genotypes 1a and 1b and reports resistance-associated substitutions to ledipasvir, elbasvir, ombitasvir, daclatasvir, velpatasvir, and pibrentasvir.
Test Interpretation
Limitations
- Specimens with viral loads <3.4 log or 2,500 IU/mL may fail to amplify, thus producing an indeterminate result.
- Testing may not be successful if the HCV RNA genotype is not 1a or 1b.
- Variants in viral subpopulations less than 20% of the total may not be detected.
Evaluated Mutations
References
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Order before initiating treatment with NS5A inhibitors. Do not order before molecular confirmation of positive HCV screen and confirmation of genotype 1a or 1b.