Evaluation of three serological tests for the detection of antiamebic antibodies applied to sera of patients from an area endemic for amebiasis.
Two enzyme immuno assays based on a single recombinant Entamoeba histolytica antigen (P1-EIA) or soluble E. histolytica extract (SA-EIA) as well as a latex agglutination test using an E. histolytica membrane fraction (M-LA) were evaluated for its use to detect anti-amebic serum antibodies in patients from Durban, South Africa, an area endemic for amebiasis. In a previous study, all three test systems were found to be reliable in terms of sensitivity and specificity when applied to sera of European individuals. By analysing a total of 167 serum samples of patients from the Durban area, suffering from invasive amebiasis (n = 76) or miscellaneous diseases unrelated to E. histolytica infection (n = 91), the present study revealed sensitivity for the detection of anti-amebic antibodies of 97.4% for SA-EIA, 86.8% for P1-EIA and 96.1% for M-LA, respectively. Specificity was high for P1-EIA (96.7%) and M-LA (92.3%) but substantially lower for SA-EIA (62.6%). In addition, antibody responses to the recombinant P1 antigen were analysed in 16 patients with amebic liver abscess before and after anti-amebic treatment. The results indicated that most of the patients lost their specific antibody response within 7 month of follow up. Therefore, P1-EIA seems to be a valuable test for distinguishing between present and past E. histolytica infections.
Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
H
H
Lotter
T F
TF
Jackson
E
E
Tannich
D000562:Amebiasis / Q000175:diagnosis* / Q000453:epidemiology; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan; D003106:Colon / Q000469:parasitology; D005060:Europe / Q000208:ethnology; D005069:Evaluation Studies as Topic; D005243:Feces / Q000469:parasitology; D006801:Humans; D007124:Immunoenzyme Techniques; D007841:Latex Fixation Tests; D008099:Liver / Q000469:parasitology; D008100:Liver Abscess; D011994:Recombinant Proteins; D013019:South Africa / Q000453:epidemiology
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D011994:Recombinant Proteins