DIAGNOSIS OF INTESTINAL AMEBIASIS USING SALIVARY IGA ANTIBODY DETECTION

This investigation sought to determine whether detection of salivary 19A antibodies to Entamoeba histolyticacould identify intestinal amebic infections among 223 school children. Four groups of children were identified through coproparasitoscopic examination: E. histolytica as the only parasite (33%); E. histolyticaand other parasites (22%); other parasites only (20%); and parasite-free (25%). The diagnostic accuracy of salivary 19A antibodies to an E. histolytica membrane extract was 91.5% (sensitivity, 85%; specificity, 98%), maintaining high predictive value at different prevalences. Also, a positive correlation (r =.753, P <.001)was observed between fecal E. histolyticamembrane antigen levels and salivary 19A antibody activity. Measurement of 19A antibodies in saliva may beuseful in diagnosing intestinal infections with E. histolytica within a wide range of prevalences. Moreover, sampling of saliva may be a useful non invasive test for immunoepidemiologic surveys. © 1990, by The University of Chicago.