ABSTRACT

In sero-diagnosis of parasitic infection, it is essential to inspect cross-reactivity between the target parasite and other parasites in order to assess diagnostic performance. The aim of this study was to determine the cut-off value of antibody titer for diagnosis of F. hepatica (FH) infection by using the micro-ELISA and diagnostic performance of this test.

The study population consisted of the following groups: FH group (n=42), Echinococcus granulosus (EG) group (n=27) and control group (n=33). The micro-ELISA test for detection of anti-F. hepatica antibody was performed in all groups.

The test was positive in all patients with FH, in 3 out of 27 (11%) patients with EG and in none of the control group. Mean antibody titer was significantly higher in the FH group compared to the EG group (23.8±0.9 DU vs. 5.7±1.2 DU; p<0.001) and compared to the control group (23.8±0.9 DU vs. 2.4±0.2 DU; p<0.001). When we used 11,5 DU as a cut-off value for sero-diagnosis of FH, the positive predictive value was 93.3%, negative predictive value was 100%, sensitivity was 100%, and specificity was 95%.

Cross-reactions are an important issue in serological diagnosis of parasitic infections. The micro-ELISA test for FH antibody can not definitely discriminate fascioliasis from hydatid disease. (Turkiye Parazitol Derg 2013; 37: 23-7)

Keywords: Fasciola hepatica, Echinococcus granulosus, micro-ELISA test