Comparison of three methods for extraction of HCV RNA in sera collected from individuals with hyperlipidemia, hyperbilirubinemia and hyperglobulinemia.

Efficient detection of HCV RNA in serum is critical for the diagnosis of hepatitis C virus (HCV) infection. Various nucleic acid extraction methods have been used to extract viral RNA for real-time reverse transcription PCR (RT-PCR). However, the efficiencies of extraction methods for HCV RNA in sera collected from individuals with hyperlipidemia, hyperbilirubinemia and hyperglobulinemia have not been investigated. In the present study, the efficiencies of three extraction methods, i.e., Trizol, guanidine isothiocyanate and silica nanoparticles, were evaluated and compared. All serum samples were collected from HCV-infected patients. For serum samples in which bilirubin, lipids and globulins were all within the normal range, the medians of HCV RNA concentration with Trizol, guanidine isothiocyanate and silica method were 2.25×10(4), 2.80×10(4) and 3.26×10(5)IU/ml HCV RNA respectively (n=180). For hyperlipidemia serum samples, the medians were 6.70×10(3), 8.79×10(3) and 1.10×10(6) respectively (n=158). For hyperbilirubinemia serum samples, the medians were 5.71×10(4), 1.59×10(5) and 1.09×10(6) respectively (n=107). For hyperglobulinemia serum samples, the medians were 3.44×10(4), 3.10×10(4) and 3.06×10(5) respectively (n=71). The medians were highest with silica method from all these types of serum samples. The silica method is, therefore, efficient for HCV RNA extraction even for sera from hyperlipidemia, hyperbilirubinemia and hyperglobulinemia patients.