Dot enzyme-linked immunosorbent assay (Dot-ELISA): comparison with standard ELISA and complement fixation assays for the diagnosis of human visceral leishmaniasis.
The dot enzyme-linked immunosorbent assay (Dot-ELISA), standard ELISA and the complement fixation (CF) tests were compared in the serodiagnosis of African visceral leishmaniasis (kala-azar). Assay sensitivity was determined using sera from 44 patients with parasitologically confirmed kala-azar. Using the Dot-ELISA, 42 of 44 patients (95%) were positive at a reciprocal titer of greater than or equal to 32 (titer range 512-524 288). In the standard ELISA technique, 43 of 44 patients (98%) were positive (titer range 32-32 768). At a reciprocal titer of greater than or equal to 8 in the CF test, 35 patients (80%) were positive, 1 (2%) was negative and 8 patients (18%) showed anticomplementary (AC) activity (titer range 8-2048). Specificity, determined using 33 sera from healthy individuals not living in endemic areas, was 97% in both the Dot-ELISA and the standard ELISA (32 of 33 sera); in he CF test, all sera were negative except 1 (3%) which showed AC activity. Sera from patients with Chagas' disease cross-reacted in the dot-ELISA up to a titer of 512. In the standard ELISA, cross-reactions occurred mainly using sera from patients with Chagas' disease, malaria and syphilis, and to a lesser extent with sera from amebiasis, schistosomiasis and trichinosis patients. Overall titer agreement in replicate experiments was highest in the Dot-ELISA (89%), followed by the standard ELISA (80%) and the CF test (72%).
D000906:Antibodies / Q000032:analysis; D000941:Antigens / Q000276:immunology; D014355:Chagas Disease / Q000276:immunology; D003168:Complement Fixation Tests; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007124:Immunoenzyme Techniques; D007891:Leishmania / Q000276:immunology; D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000276:immunology; D008288:Malaria / Q000276:immunology; D010272:Parasitic Diseases / Q000276:immunology
D000906:Antibodies; D000941:Antigens