The Correlation between Hepatitis C Core Antigen and Hepatitis C Virus RNA Levels with Respect to Human Immunodeficiency Virus Status, Hepatitis C Virus Genotype and Interferon-Lambda-4 Polymorphism

Abstract

Objectives: Serum hepatitis C virus (HCV) core antigen (HCVcAg) concentrations correlate with HCV RNA levels in HCV monoinfected patients. Data in HCV/HIV coinfected patients are still limited. We aim to compare the use of HCVcAg measurement with respect to HIV status, HCV genotypes, interferon-lambda-4 (IFNL4) polymorphism and clinical parameters. Methods: We analyzed an untreated cohort of 104 patients with HCV monoinfection and 85 patients with HCV/HIV coinfection. Serum HCVcAg was measured by a commercial chemiluminescent microparticle immunoassay. The presence of IFNL4 polymorphism ss469415590 was identified by real-time PCR. Results: log₁₀ HCVcAg levels were significantly correlated with corresponding log₁₀ HCV RNA levels (r = 0.889, p < 0.001), but not with ALT levels and liver stiffness. The correlation between HCV RNA and HCVcAg was particularly high in coinfected patients and those with high viremia. Mean log₁₀ HCVcAg concentration was significantly higher in coinfected patients than in monoinfected patients. Patients harboring the TT/TT genotype of ss469415590 had significantly higher levels of log₁₀ HCVcAg than those with the non-TT/TT genotype. HCVcAg levels were similar across HCV genotypes. Conclusions: HCVcAg concentrations had an excellent correlation with HCV RNA levels, particularly in HCV/HIV-coinfected individuals and might be associated with IFNL4 polymorphism. HCVcAg testing could be used as an alternative to HCV RNA assays in resource-limited settings.