Serological confirmatory testing of alveolar and cystic echinococcosis in clinical practice: results of a comparative study with commercialized and in-house assays.
Sera of 50 patients with either cystic (CE) or alveolar echinococcosis (AE) in different clinical stages were examined for the presence of anti-Echinococcus-antibodies. Antibody-screening was performed with ELISA, IHA and IFAT, and confirmatory testing was done by the commercialized E. multilocularis-specific Em2plus-ELISA versus an in-house E. multilocularis-specific Em10-ELISA. Sera with discrepant confirmatory results were subjected to a commercial Echinococcus IgG Western blot (WB). In sera from patients with CE, the Em2plus-ELISA showed cross-reactions in 23.5%, whereas the Em10-ELISA did not exhibit any cross-reactivity. Cross-reactivity paralleled active infection with high antibody titers in the screening assays. In sera from patients with AE, confirmation by both ELISAs was achieved in 57.6%, mostly in patients with an advanced stage of the disease and high antibody titers in the screening assays. False-negative reactions of both ELISAs occurred in 30.3%, mostly in patients who had low antibody levels in the screening tests. The Em2plus-ELISA exhibited fewer false-negative reactions than the Em10-ELISA. The WB confirmed the positive results of either assay and was the assay with the highest reliability at different stages of CE and AE, followed by the Em2plus-ELISA for AE. High antibody titers in the screening assays will favour the detection of species-specific antibodies in either form.
Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Clinic Bonn, Sigmund Freud Str. 25, 53105 Bonn, Germany.
Ingrid
I
Reiter-Owona
Beate
B
Grüner
Matthias
M
Frosch
Achim
A
Hoerauf
Peter
P
Kern
Dennis
D
Tappe
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D015153:Blotting, Western; D003429:Cross Reactions; D004443:Echinococcosis / Q000175:diagnosis* / Q000276:immunology; D004445:Echinococcosis, Pulmonary / Q000175:diagnosis* / Q000276:immunology; D004446:Echinococcus / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005188:False Negative Reactions; D005260:Female; D005455:Fluorescent Antibody Technique; D006386:Hemagglutination Tests; D006801:Humans; D008297:Male; D008875:Middle Aged; D011933:Reagent Kits, Diagnostic; D012698:Serologic Tests / Q000379:methods*; D013045:Species Specificity
D000909:Antibodies, Helminth; D011933:Reagent Kits, Diagnostic