Comparison of Native Hydatid Cyst Fluid (HCF), Lyophilized HCF, Antigen B (AgB) and Lyophilized AgB (LAgB) Originated from Echinococcus granulosus Sensu Stricto for Sero-Diagnosis of Active, Transitional and Inactive Human Liver Cystic Echinococcosis

Background: Cystic echinococcosis (CE) is an important zoonotic parasitic disease caused by the larval stage or metacestode of the tapeworm Echinococcus granulosus sensu lato. Due to treatment protocols for different liver cysts, diagnosis of cyst stages is very important. Different antigens have been used for CE diagnosis. However, each one is more sensitive and effective for the diagnosis of specific CE stages is not known well. We aimed to compare Native Hydatid Cyst Fluid (HCF), Lyophilized Hydatid Cyst Fluid (LHCF), antigen B (AgB) and Lyophilized antigen B (LAgB) originated from E. granulosus sensu stricto (G1-G3) genotype, for sero- diagnosis of active, transitional and inactive human liver CE using ELISA technique. Methods: The HCF was collected aseptically from liver CE cysts of sheep slaughtered from 2018 to 2019 in Shiraz slaughterhouse, Southern, Iran. The cysts were characterized by PCR and sequencing for genotype specification. Four types of antigens were used: HCF, LHCF, AgB and LAgB originated from E. granulosus sensu stricto (G1-G3) genotype. Thirty-three serum samples from active, transitional, and inactive human cysts were collected. Overall, 48 samples from other parasitic diseases and 60 samples from healthy subjects as negative controls were checked using four antigens by ELISA method. Results: The best diagnostic sensitivity with 96.97% was observed by anti-LHCF IgG ELISA test. The best specificity with 95.37% was observed in ELISA test using LAgB. Conclusion: Simultaneous test of sera with anti-LHCF IgG ELISA and anti-LAgB IgG ELISA would be the best in the diagnosis of human liver cystic echinococcosis.