Hepatitis C is a global problem caused by the hepatitis C virus (HCV). HCV is a blood-borne virus that infects approximately 200 million people worldwide. Laboratory testing plays an important role in diagnosing HCV, evaluating patients for treatment, monitoring patients during treatment, and following up after treatment. There are 6 major genotypes of HCV with genotypes 1 and 4 being more difficult to treat and less responsive to interferon-based therapy.

1. Hepatitis C Dr Kamran Afzal Asst Prof Microbiology

5. Hepatitis C Virus Genome hypervariable region capsid envelope protein protease/helicase RNA-dependent RNA polymerase c22 5’ core E1 E2 NS2 NS3 33c NS4 c-100 NS5 3’ Heterogeneity (results in difficulty in diagnosis, treatment and immunization)

6. Terminology Family Genus Species Genotype Subtype Quasispecies Flaviviridae Hepacivirus HCV

8. Distribution of HCV Genotypes

10. Routes of Transmission

15. Clinical Course Of Hepatitis C Acute Hepatitis 70-85% 15-30% Chronic Hepatitis Chronic Hepatitis 50% Recovery 20% Cirrhosis + or – HCC

16. Lab Diagnosis Serology ELISA Anti HCV Ab Core Ag RIBA Pathological Assays Liver biopsy FNAC Molecular Assays PCR RT- PCR b-DNA TMA Genotyping Biochem Raised SGOT Raised SGPT Raised S. Bil Deranged PT Radiological examination : Ultra sonography , CT

17. Serologic Pattern - Acute Symptoms +/- Time after Exposure Titer anti-HCV ALT Normal 0 1 2 3 4 5 6 1 2 3 4 Years Months HCV RNA 200 400 600 800 1000 Monophasic

18. Serologic Pattern - Chronic Symptoms +/- Time after Exposure Titer anti-HCV ALT Normal 0 2 4 6 1 2 3 4 Years Months HCV RNA 200 400 600 800 1000 Polyphasic

28. Interpretation of HCV Assays Anti-HCV HCV RNA Interpretation Positive Positive Acute or chronic hepatitis C depending on the clinical context Positive Negative Resolution of HCV; acute HCV during low-level viremia Negative Positive Early acute HCV; chronic HCV in immunosuppression; false positive Negative Negative No HCV infection

40. Cont.. HCV RNA positive: patient is chronically infected HCV RNA negative: patient is most likely not infected, but low-level or Intermittent viremia possible. Repeat RNA testing recommended in 6-12 m Qualitative PCR or real-time PCR Infant born to HCV positive mother; infant still ab. positive at 18 m >800 000 IU/mL is considered high, more difficult to treat Use same quantitative assay before treatment and measure 4- and 12-wk responses Quantitative tests such as Quantitative qPCR, bDNA, or RT- PCR HCV antibody and RNA positive, eligible for treatment Interpretation and Comments Test to Use Clinical Situation