Introduction: Hepatitis C, caused by hepatitis C virus (HCV) can be a mild illness lasting a few weeks or can cause lifelong liver cirrhosis and cancer. Today although the sensitivity of diagnostic tests is increasing; it has often been associated with decreased specificity so the rate of false-positive test results is increasing. The aim of this study was to compare the false-positive rates of anti-HCV results.
Methods: During the period of 18.07.2011 to 18.12.2013; blood samples of patients admitted to Konya Numune Hospital were screened for anti-HCV using chemiluminescence immunoassay (CIA). After 2012; the new version of same anti-HCV test was used. Borderline and reactive results were retested and tests which were reactive in repeated CIA were confirmed by a recombinant immunoblot-assay (RIBA). Subjects with a positive RIBA test were considered to have been as true positive anti-HCV.
Results: A total of 54178 sera were tested for anti-HCV during the period of 18.07.2011 to 18.12.2013 and 649 sera were positive with chemiluminescence method. 374 of reactive cases were confirmed by RIBA. The RIBA results showed 171 (45.7 %) negative, 163 (43.5 %) positive, and 40 (10.7 %) indeterminate results. By using the new version of the test; the rate of false positive and indeterminate anti-HCV test results decreased from 75.1% to 35.5 %.
Conclusions: In this study it was observed that lower false positive rates of newly developed test. Lowering the false positive rate of ELISA tests will provide more confidence to use these tests in the diagnosis of HCV. There is a need for further studies on this issue.