Molecular Diagnosis of Toxoplasmosis in Non Immune Pregnant Females

Amany A. Abdel Aal, Samar S. Attia, Nihal A. Hanafy, Abeer S. Al-Antably, Marwa A. Hassan, Walid El-Sherbiny, Aml S. Nasr


BACKGROUND AND AIM: Infection with the protozoan parasite Toxoplasma gondii has a worldwide distribution. Congenital infection is the most important part of the disease burden due to Toxoplasma infection in humans. Early diagnosis of maternal infection helps to prevent severe complications of toxoplasmosis. In the present study, three PCR assays (conventional, nested & quantitative) were evaluated for diagnosis of recent toxoplasmosis based on detection of Toxoplasma B1 gene.

MATERIAL AND METHODS: The present study was carried out on 150 pregnant females who were serologically negative for anti-Toxoplasma IgG and IgM antibodies.

RESULTS: The results revealed that out of 12 true positive cases (by 2 out of the 3 PCR protocols), 8 cases were positive by cPCR, 11 cases were positive by nPCR and 12 cases were positive by qPCR. Accurate estimation of genomic Toxoplasma DNA in positive samples was achieved by qPCR. In general, PCR assays offer a sensitive alternative of serological methods for diagnosis of recent maternal toxoplasmosis. In addition, qPCR decreases the risk of contamination of PCR products being a closed tube method and helps in estimation of infection load.

CONCLUSIONS: We recommend screening of high-risk pregnant women by qPCR for early diagnosis of toxoplasmosis and proper management.


Toxoplasma gondii; PCR; Molecular diagnosis; non-immune; pregnancy

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