EVALUATION OF THE NEW AUTOMATED ENZYMUN-TEST(R) ANTI-HBC PLUS FOR THEDETECTION OF HEPATITIS-B VIRUS CORE ANTIBODY

The new automated Enzymun-Test(R) Anti-HBc Plus for the detection of a ntibodies to hepatitis B virus (HBV) core antigen (anti-HBc) after pre treatment with reducing agents dithiothreitol (25 degrees C; + DTT) or potassium bisulfite (37 degrees C; + MBS) was evaluated by testing 57 1 serum and plasma samples. The panel included dilution series of refe rence standards and samples from chronic carriers, one seroconversion panel, samples from patients in acute or chronic stage of the disease or resolved hepatitis B, preselected sera from blood donors that were initially reactive in an anti-HBc assay without pretreatment, potentia lly cross-reactive serum samples obtained from patients suffering from other diseases or with passed infections other than HBV, pregnant wom en and individuals with HBV vaccination. The IMx CORE(TM) (Abbott Diag nostics) served as reference assay. Discrepant samples were further in vestigated with two different commercial anti-HBc enzyme immunoassays, other HBV-specific serological markers and HBV DNA hybridization. The sensitivity of the Enzymun-Test Anti-HBc Plus (25 degrees C; + DTT, a nd 37 degrees C; + MBS) in comparison to the reference assay was 100%. The IMx CORE showed a twofold higher sensitivity than Enzymun-Test An ti-HBc Plus for anti-HBc detection in dilution series of serum samples from HBV carriers. The agreement in terms of specificity of the Enzym un-Test Anti-HBc Plus (25 degrees C; + DTT, and 37 degrees C; + MBS) a nd in comparison to IMx CORE was 97.4 and 96.4%, respectively. After r esolution of discrepant results (3 samples were tested false negative with IMx CORE), the agreement in terms of specificity of the Enzymun-T est Anti-HBc Plus (25 degrees C; + DTT, and 37 degrees C; + MBS) in co mparison to the combination of the comparative assays was 98.3 and 97. 4%, respectively. In conclusion, the new automated Enzymun-Test Anti-H Bc Plus with sample pretreatment with DTT (25 degrees C; + DTT) or MBS (37 degrees C; + MBS) permits a highly sensitive and specific detecti on of anti-HBc in diagnostic virology and blood donation testing.