What strategy should be used for diagnosis of hepatitis C virus infection in clinical laboratories?

Abstract

The aim of this study was to determine a cost-effective strategy for the diagnosis of hepatitis C virus ( The diagnosis of hepatitis C virus (HCV) infection is based on the detection of anti-HCV antibodies in serum, generally by means of enzyme-linked immunosorbent assays (ELISA). Two different settings must be considered: 1) Blood banks routinely perform anti-HCV testing in blood donors to identify potentially infectious donations and to avoid posttransfusion HCV infection; 2) clinical laboratories routinely search for anti-HCV antibodies in patients with risk factors for parenterally acquired viral infections or clinical symptoms compatible with HCV infection to make appropriate clinical decisions, including therapeutic ones. By analogy with human immunodeficiency virus diagnosis, the French laws have been obliging to perform two different ELISA tests in the routine diagnosis of HCV infection in clinical laboratories for several years, while only one test was needed for blood screening.First-generation anti-HCV ELISAs were lacking sensitivity as well as specificity. This is why first-generation confirmatory assays based on immunoblot testing were developed and systematically used in samples positive in ELISA. 1,2 Since then, ELISA assays have considerably improved, and the second-or third-generation tests available today are both highly sensitive and specific. 3-6 Nevertheless, second-or third-generation immunoblot tests are still used for confirmation in most laboratories. 7,8 The detection of HCV antibodies in serum does not provide information on the replicative status of HCV, a parameter that can be useful in the management of infected patients. Polymerase chain reaction (PCR)-based assays have been developed and are capable of detecting minute amounts of HCV RNA in serum or plasma.The aim of this work was to determine whether a double ELISA determination and confirmation of positive ELISA results with immunoblot assays are still useful in clinical laboratories performing routine diagnosis of HCV infection. MATERIALS AND METHODSFrom January 1 to May 22, 1996, 3,014 consecutive requests for the detection of anti-HCV antibodies were sent to the virology laboratory by the various medical departments of our institution.The serum samples were routinely tested for the presence of anti-HCV antibodies with two different ELISAs: ORTHO HCV 3.0 ELISA Test System (ELISA3.0 HCV; Ortho Clinical Systems, Raritan, NJ), and MONOLISA anti-HCV New Ag (MONOLISA HCV; Sanofi Diagnostics Pasteur, Marnes-la-Coquette, France). ELISA 3.0 detects antibodies directed to core, nonstructural (NS) 3, NS4, and NS5 HCV antigens, while MONOLISA HCV detects antibodies directed to core, NS3, and NS4 antigens. 9 Different peptides are used in the two assays. 9 The assays were perfomed according to the manufacturers' instructions, and, in each sample, the optical density (OD) ratio was calculated by dividing the sample OD by the assay control OD. Samples with an OD ratio Ն2 were considered positive, samples with an OD ratio between 1 and 2 we...

Use and interpretation of virological tests for hepatitis C

“…Given the good performance of current anti-HCV EIAs, however, immunoblot tests are clinically obsolete. 22 These tests are still used in blood banks, where low-risk populations are tested and the positive predictive value of EIA is significantly lower than in diagnostic use. Even their utility in blood donor screening may decrease in the future with the advent of systematic molecular testing for HCV RNA in the United States and the European Serologic Determination of the HCV Genotype.…”

Use and interpretation of virological tests for hepatitis C

“…Given the good performance of current anti-HCV EIAs, however, immunoblot tests are clinically obsolete. 22 These tests are still used in blood banks, where low-risk populations are tested and the positive predictive value of EIA is significantly lower than in diagnostic use. Even their utility in blood donor screening may decrease in the future with the advent of systematic molecular testing for HCV RNA in the United States and the European Union.…”

“…22 Anti-HCV negativity with HCV RNA positivity is exceptional, occurring rarely in immunocompetent patients with chronic hepatitis C; this situation can arise (albeit rarely with current EIAs) 21 when the patient is on hemodialysis or is profoundly immunodepressed.…”

Hepatitis C Virus; Sensitivity of Anti Hepatitis C Virus Antibodies Thru Elisa Method in Comparison to Hepatitis C Virus Ribonucleic Acid by PCR Method

“…In patient's potentially immunocompromised undergoing dialysis, for detecting viremia PCR is the reliable test only. 26 The most common method of assessing HCV infection is the serological diagnosis of anti HCV antibody at present. Although a positive result by ELISA and RIBA HCV indicates active HCV infection it does not distinguish between current infection and previous exposure.…”

“…A study by Pawlotsky and associates 26 determined that a single test by ELISA 3 determination in favor of analysis of viral Hepatitis C disease is sufficient in investigation settings and that for follow-up a repeated ELISA with RIBA was no longer recommended.…”