Comparison of Dot-ELISA and Sandwich ELISA Diagnostic Tests in Detection of Human Hydatidosis

Hydatidosis, caused by the larval stage of Echinococcus granulosus, is one of the most important zoonosis with worldwide distribution. As its diagnosis by clinical symptoms and scanning alone is difficult and confusing, we designed the present study to achieve a sensitive and simple diagnostic method for epidemiological studies. Sera (250 samples) were collected from 90 cases of hydatidosis proven by surgical operation, 80 patients with diseases other than hydatidosis and 80 healthy cases. The antigen (Ag) used was a crude hydatid fluid Ag obtained from lung and liver cycts of sheep slaughtered in Tehran abattoir (Iran). The result of dot-ELISA showed 100% sensitivity and 98.75% specificity . Positive and negative predictive values were 97.82% and 100% respectively. In the case of sandwich ELISA, the results were as follows: 92.22% sensitivity, 98.75% specificity, positive and negative predictive values: 97.64% and 95.75 %, respectively. In both techniques, cross reaction with fasciolosis was observed for two cases. In conclusion, although these two tests had very similar results, dot-ELISA was more acceptable with respect to its higher sensitivity and simplicity in practice. Iran. Biomed. J. 9 (2): 91-94, 2005