Korean J Parasitol.  2014 Oct;52(5):493-499. 10.3347/kjp.2014.52.5.493.

A New IgG Immunoblot Kit for Diagnosis of Toxoplasmosis in Pregnant Women

• Khammari I
• Saghrouni
• Lakhal S
• Bouratbine A
• Ben Said M
• Boukadida

• KMID: 1792214
• DOI: http://doi.org/10.3347/kjp.2014.52.5.493

Abstract

The determination of the accurate immune status of pregnant women is crucial in order to prevent congenital toxoplasmosis. Equivocal results with conventional serological techniques are not uncommon when IgG titers are close to the cut-off value of the test, so that a confirmatory technique is needed. For this purpose, we developed a homemade immunoblot (IB) using soluble extract of Toxoplasma gondii tachyzoites and assessed it by testing 154 positive, 100 negative, and 123 equivocal sera obtained from pregnant women. In order to select the more valuable bands in terms of sensitivity and specificity, we used the Youden Index (YI). The highest YIs were those given by the 32, 36, 98, 21, and 33 bands. The simultaneous presence on the same blot of at least 3 bands showed a much higher YI (0.964) and was adapted as the positivity criterion. The analysis of results showed that our homemade IB correlated well with the commercial LDBIO Toxo II IgG(R) kit recently recommended as a confirmatory test (96.7% of concordance).

Keyword

Toxoplasma gondii; toxoplasmosis; serodiagnosis; immunoblot; soluble tachyzoite antigen

MeSH Terms

Female
Humans
Immunoenzyme Techniques/*methods
Immunoglobulin G/*blood/immunology
Pregnancy
Reagent Kits, Diagnostic
Toxoplasmosis/*diagnosis
Immunoglobulin G
Reagent Kits, Diagnostic