The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosis
Determining specific immune status against Toxoplasma gondii is essential for assessing the risk of reactivation in immunocompromised patients or defining serological monitoring and appropriate prophylactic measures during pregnancy. In France, toxoplasmosis serological screening requires systematic...
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| Format: | Article |
| Language: | English |
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EDP Sciences
2015-01-01
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| Series: | Parasite |
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| Online Access: | http://dx.doi.org/10.1051/parasite/2015022 |
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| author | Mouri Oussama Kendjo Eric Touafek Feriel Fekkar Arnaud Konte Ousmane Imbert Sebastien Courtin Régis Mazier Dominique Paris Luc |
| author_facet | Mouri Oussama Kendjo Eric Touafek Feriel Fekkar Arnaud Konte Ousmane Imbert Sebastien Courtin Régis Mazier Dominique Paris Luc |
| author_sort | Mouri Oussama |
| collection | DOAJ |
| description | Determining specific immune status against Toxoplasma gondii is essential for assessing the risk of reactivation in immunocompromised patients or defining serological monitoring and appropriate prophylactic measures during pregnancy. In France, toxoplasmosis serological screening requires systematic testing for IgM and IgG antibodies. The Platelia Toxo IgG and IgM test (Bio-Rad) is one of the most widely used tests for anti-toxoplasmic antibody detection. We performed a study on 384 sera, including 123 IgG negative (<6 IU/mL) and 261 IgG equivocal (6–9 IU/mL) sera tested with Platelia Toxo IgG and collected during routine screening at Pitié-Salpêtrière Hospital, Paris, France to determine the best-performing IgG titer cut-off value. Out of these 383 sera, 298 were IgM negative by Platelia Toxo IgM and 86 were IgM positive. All sera were also tested against Toxo IgG II LD BIO western blot test as confirmation. Our results indicated that an IgG titer cut-off value of ≥4.4 IU/mL for the Platelia Toxo IgG met the definition of positivity, a value significantly lower than that indicated by the manufacturers. In the presence of IgM antibodies, the IgG titer cut-off decreased significantly to a value ≥0.2 IU/mL. This latter cut-off also allowed adequate diagnosis of proven toxoplasmosis seroconversion in 76.7% of cases (33/43). Our findings may improve toxoplasmosis care by reducing therapeutic intervention time and eliminating the need for further serological monitoring. |
| first_indexed | 2024-03-09T08:56:37Z |
| format | Article |
| id | doaj.art-d8ad8e7ea2134e22baa4e152e932b6f2 |
| institution | Directory Open Access Journal |
| issn | 1776-1042 |
| language | English |
| last_indexed | 2024-03-09T08:56:37Z |
| publishDate | 2015-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | Parasite |
| spelling | doaj.art-d8ad8e7ea2134e22baa4e152e932b6f22023-12-02T13:02:48ZengEDP SciencesParasite1776-10422015-01-01222210.1051/parasite/2015022parasite150005The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosisMouri OussamaKendjo EricTouafek FerielFekkar ArnaudKonte OusmaneImbert SebastienCourtin RégisMazier DominiqueParis LucDetermining specific immune status against Toxoplasma gondii is essential for assessing the risk of reactivation in immunocompromised patients or defining serological monitoring and appropriate prophylactic measures during pregnancy. In France, toxoplasmosis serological screening requires systematic testing for IgM and IgG antibodies. The Platelia Toxo IgG and IgM test (Bio-Rad) is one of the most widely used tests for anti-toxoplasmic antibody detection. We performed a study on 384 sera, including 123 IgG negative (<6 IU/mL) and 261 IgG equivocal (6–9 IU/mL) sera tested with Platelia Toxo IgG and collected during routine screening at Pitié-Salpêtrière Hospital, Paris, France to determine the best-performing IgG titer cut-off value. Out of these 383 sera, 298 were IgM negative by Platelia Toxo IgM and 86 were IgM positive. All sera were also tested against Toxo IgG II LD BIO western blot test as confirmation. Our results indicated that an IgG titer cut-off value of ≥4.4 IU/mL for the Platelia Toxo IgG met the definition of positivity, a value significantly lower than that indicated by the manufacturers. In the presence of IgM antibodies, the IgG titer cut-off decreased significantly to a value ≥0.2 IU/mL. This latter cut-off also allowed adequate diagnosis of proven toxoplasmosis seroconversion in 76.7% of cases (33/43). Our findings may improve toxoplasmosis care by reducing therapeutic intervention time and eliminating the need for further serological monitoring.http://dx.doi.org/10.1051/parasite/2015022ToxoplasmosisToxoplasma gondiiCongenital toxoplasmosisPregnant womenWestern blot |
| spellingShingle | Mouri Oussama Kendjo Eric Touafek Feriel Fekkar Arnaud Konte Ousmane Imbert Sebastien Courtin Régis Mazier Dominique Paris Luc The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosis Parasite Toxoplasmosis Toxoplasma gondii Congenital toxoplasmosis Pregnant women Western blot |
| title | The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosis |
| title_full | The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosis |
| title_fullStr | The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosis |
| title_full_unstemmed | The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosis |
| title_short | The impact of lowering the cut-off value on the sensitivity of the Platelia Elisa IgG (Bio-Rad) test for toxoplasmosis diagnosis |
| title_sort | impact of lowering the cut off value on the sensitivity of the platelia elisa igg bio rad test for toxoplasmosis diagnosis |
| topic | Toxoplasmosis Toxoplasma gondii Congenital toxoplasmosis Pregnant women Western blot |
| url | http://dx.doi.org/10.1051/parasite/2015022 |
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