PCR detection of Toxoplasma gondii DNA versus serological diagnosis in women suffering from repeated abortion

Abstract

Background: This study was conducted to test the utility of polymerase chain reaction (PCR) assay to detect recent infections with Toxoplasma in pregnant women. T.gondii DNA was detected by using B1 gene as a target for amplification which is highly specific for T.gondii and is well conserved among all of the tested strains. Results: This study revealed the following findings:(1) PCR was positive in 63 subjects, including 58 high risk cases (77.3%) and 5 of controls (12.5%). (2) 17 high risk cases (24.6%) had false positive IgM and 5 of controls (12.5%) had false negative result for IgM. (3) 17 high risk cases (32.7%) had false positive IgG and 5 of controls (12.5%) had false negative IgG. (4) No significant association between eating raw meat or contact with cats and positive ELISA for PCR but there is highly significant association between women with contact with soil and positive PCR. (5) No significant relation between residency and either ELISA or PCR. (6) Significant negative correlation between the age of the studied women and positivity of PCR. Conclusion: this study highlights the need for a confirmatory test to detect primary acute toxoplasmosis in pregnant women. It demonstrates the possibility of defining and selecting the high-risk cases for mother-to-child transmission of infection by combining specific serology and PCR tests to formulate a specific approach