Evaluation of enzyme-linked immunosorbent assay for the serodiagnosis of amebiasis

This report describes the development and evaluation of an enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to Entamoeba histolytica. Highly sensitive and reproducible results were obtained in antigen-coated plates prepared by air-drying at 37 degrees C. Comparison of the ELISA with indirect fluorescent antibody and indirect hemagglutination techniques showed that the former was slightly more sensitive than the two latter methods. The specificity was evaluated by testing specially chosen population groups. ELISA was negative in 96.4% of 693 normal adults and children and in 96.6% of 377 patients with various parasitic, bacterial, mycotic, and other clinical diseases. The assay was positive in 26% of 461 patients with suspected amebiasis and in all of 53 patients with amoebic liver abscess. The ELISA was found to be a specific, highly sensitive, and reliable procedure for detecting anti-E. histolytica antibodies in humans.