Serological Diagnosis of Lung Cystic Hydatid Disease Using the Synthetic p176 Peptide

Cystic hydatid disease (CHD) is a worldwide zoonosis caused by the larval stage of the dog tapeworm Echinococcus granulosus. Diagnosis is based on imagenological tools (abdominal ultrasound, chest X-rays, or computed tomography [CT] scan). Serologi-cal antibody-detecting assays, using diverse native antigens, have been used as a supportive diagnostic tool, but their sensitivities and specificities differ greatly. The use of synthetic peptides as antigens should provide more reliability and allow better assess-ment and comparison of test formats and case series. The synthetic peptide p176, corresponding to the N-terminal extreme of the subunit of antigen B (AgB8/1), has shown promising performances for diagnosis of CHD.We evaluated the performance of the synthetic peptide p176 for the diagnosis of pulmonary hydatid disease in an enzyme-linked immunosorbent assay (ELISA) format. Sixty-one serum samples from patients with a diagnosis of pulmonary hydatidosis confirmed by surgery and 128 from healthy volunteers were tested. The overall sensitivity and specificity of the p176 ELISA for lung CHDwere 78.69 % and 96.88%, respectively. On bivariate analysis, positive serum antibody reactions were associated with the presence of complications and with the number of cysts (single/multiple). Only the presence of persistent complications significantly associated with seroposi-tivity onmultivariate logistic regression analysis (odds ratio [OR], 9.58; 95 % confidence interval [CI], 2.15 to 42.6; P 0.003). The p176 ELISA performs well for the diagnosis of lung CHD and adds an easily reproducible diagnostic assay to the existing diagnostic tools. Cystic hydatid disease (CHD), still a neglected disease despitebeing highly endemic in many livestock-raising region