Characterization and optimization of sheep hydatid fluid antigen and its application in the latex test

Abstract

It was characterized and optimized sheep hydatid fluid antigen and applied in latex fixation tests as screening test for serological diagnosis of patients with Echinococcus granulosus cysts. We evaluated 40 sera, 15 sera positive by immunoblot from patients with E. granulosus infection, 10 sera from patients with other parasitic diseases and 15 sera from healthy subject. Three of the 15 hydatidosis sera were negative and 0 / 25 sera with hydatidosis were reactive. The sensitivity was 80% (95%CI: 56.4 to 100%), specificity was 100% (96.7 to 100%), positive predictive value of 100% (95.8 to 100%), negative predictive value of 83.3 (30.4 to 69.6%), and repeatability and reproducibility of 100%. We recommended the use of this test for the diagnosis of hydatid disease, because it is simple, fast and reproducible, as a kit in the laboratory or in epidemiological field studies.