Hepatitis C Genotyping can be used to help predict the outcome of therapy and to influence the choice of therapeutic drugs. Clinical outcome depends on the genotype of the infection, pretreatment viral load, and whether or not liver cirrhosis is present. Genotypes 1a and 1b have the poorest clinical outcomes with sustained viral response of only 46% with combination antiviral therapy.
About HCV Genotyping
Hepatitis C virus (HCV) is a member of the Flaviviridae family. It is a single-stranded, positive-sense RNA virus, which is spherical and lipid-enveloped. HCV was discovered in the late 1980s and is considered to be one of the leading causes of liver disease in the United States. Hepatitis C Genotyping can be used to help evaluate the outcome of HCV therapy and to influence the choice of therapeutic drugs. The ability to achieve a sustained virological response is influenced by the genotype of the infection, pretreatment HCV-RNA levels (viral load), early response to therapy and whether or not liver cirrhosis is present.1-3 Six major genotypes (1 through 6) have been identified to date with more than 50 subtypes; however, most patients with HCV typically have only one principal genotype, rather than multiple genotypes.5-7 Approximately 75% of Americans with HCV have genotype 1 of the virus (subtypes 1a or 1b), and 20-25% have genotypes 2 or 3, with small fraction of patients infected with genotypes 4, 5, or 6.8Procedure
Extraction of nucleic acid from plasma or serum followed by amplification. The amplified DNA is converted to single-stranded DNA via exonuclease digestion and is then combined with a signal buffer containing ferrocene-labeled signal probes that are specific to the different types/subtypes. The mixture of amplified sample and signal buffer is loaded onto the eSensor cartridge, which contains single-stranded oligonucleotide capture probes bound to gold-plated electrodes. The cartridge is inserted into the XT-8 instrument where the single-stranded targets first hybridize to the matched signal probes then hybridize to the complementary sequences of the capture probes. The presence of each target is determined by voltammetry, which generates specific electrical signals from the ferrocene-labeled signal probe. This test has not been cleared or approved for diagnostic use by the U.S. Food and Drug Administration.Specificity
Detects all 6 HCV genotypes including types 1-6 and subtypes 1a, 1b, 2a/2c, 2b. This test has a limited ability to detect mixed genotypes.
1-4 business days from receipt of specimen. Testing performed Mondays, Wednesdays and Fridays.
|Specimen Type||Order Code||CPT Code||NY Approved||Volume||Assay Range||Special Instructions|
|plasma||1301||87902||Yes||2 mL (min. 250 IU/mL)||Genotypes: 1a, 1b, 2a/2c, 2b, 3, 4, 5, and 6||
2 mL (min. 250 IU/mL)
Genotypes: 1a, 1b, 2a/2c, 2b, 3, 4, 5, and 6
Genotypes: 1a, 1b, 2a/2c, 2b, 3, 4, 5, and 6.Shipping
Ship Monday through Friday. Friday shipments must be labeled for Saturday delivery. All specimens must be labeled with patient's name and collection date. A Viracor Eurofins test requisition form must accompany each specimen. Multiple tests can be run on one specimen. Ship specimens FedEx Priority Overnight® to: Viracor Eurofins, 18000 W 99th St., Lenexa, KS 66219Causes for Rejection
Specimens beyond their acceptable length of time from collection as listed in the specimen handling, HCV RNA concentrations too low to allow for genotype testing, concentrations too low to allow antiviral resistance testing, or specimen types other than those listed.
Specimens are approved for testing in New York only when indicated in the Specimen Information field above.
The CPT codes provided are based on Viracor Eurofins' interpretation of the American Medical Association's Current Procedural Terminology (CPT) codes and are provided for informational purposes only. CPT coding is the sole responsibility of the billing party. Questions regarding coding should be addressed to your local Medicare carrier. Viracor Eurofins assumes no responsibility for billing errors due to reliance on the CPT codes illustrated in this material.
PCR tests are performed pursuant to a license agreement with Roche Molecular Systems, Inc.References
- Fried MW, Shiffman ML, Reddy KR, Smith C, Marinos G, Goncales FL Jr, et al. Peginterferon alfa-2b plus ribavirin for chronic hepatitis C virus infection. New Eng J Med. 2002 Sep 26;347(13):975-82.
- Ferenci P, Fried MW, Shiffman ML, Smith CI, Marinos G, Goncales FL Jr, et al. Predicting sustained virological responses in chronic hepatitis C patients treated with peginterferon alfa-2a (40KD)/ribavirin. J Heptol. 2005 Sep;43(3):425-33.
- David GL, Wong JB, McHutchison JG, Manns MP, Harvey J, Albrecht J. Early virologic response to treatment with peginterferon alfa-2b plus ribavirin in patients with chronic hepatitis C. Hepatology. 2003 Sep;38(3):645-52.
- Incivek™ package insert. Cambridge, MA: Vertex Pharmaceuticals Incorporated; 2011.
- Manns MP, McHutchison JG, Gordon SC, et al. Peginterferon alfa-2b plus ribavirin compared with interferon alfa-2b plus ribavirin for initial treatment of chronic hepatitis C: a randomized trial. Lancet. 2001; 358:958-65.
- Fried MW, Shiffman ML, Reddy R, Smith C, Marinos G, Goncales FL Jr, et al. Peginterferon alfa-2a plus ribavirin for chronic hepatitis C virus infection. N Engl J Med. 2002 Sep 26;347(13):975-82.
- Hadziyannis SJ, Sette H Jr, Morgan TR, Balan V, Marcellin P, Ramadori G, et al. Peginterferon alpha-2a and ribavirin combination therapy in chronic hepatitis C: a randomized study of treatment duration and ribavirin dose. Ann Intern Med. 2004 Mar 2;140(5):346-55.
- McHutchison JG, Gordon SC, Schiff ER, Shiffman ML, Lee WM, Rustgi VK, et al. Interferon alfa-2b alone or in combination with ribavirin as initial treatment for chronic hepatitis C. N Engl J Med. 1998 Nov 19;339(21):1485-92.