Screening for the Detection of Toxoplasma gondii IgG, IgM and IgA in Females of Reproductive Age from Western Romania

Abstract

Toxoplasma gondii, a zoonotic protozoan parasite, has the capacity to infect the fetus if the pregnant woman primarily acquires the infection during pregnancy. We evaluated the prevalence of T. gondii IgG, IgM and IgA antibodies in women of reproductive age residing in Western Romania. We also assessed the value of adding a T. gondii IgA test to the serologic panel for the diagnosis of toxoplasmosis, including the detection of a recently acquired infection. Serologic testing to demonstrate the presence of T. gondii IgG antibodies was conducted in 1317 females aged 15–45 years. T. gondii IgM and IgA antibody tests were performed in those with detectable IgG antibodies and IgG avidity test was performed if IgM and/or IgA screening test results were positive. T. gondii IgG were detected in 607 (46.09%; 95%CI: 43.41–48.79) of 1317 study participants and IgG seroprevalence tended to increase with age from 35.44% (95%CI: 29.89–41.30) in age group 15–24 years to 62.85% (95%CI: 56.57–68.82) in age group 35–45 years, showing a significant age-associated increase (p < 0.001). Of the 607 persons with detectable T. gondii IgG antibodies, T. gondii IgM antibodies were demonstrated in 8.90% (95%CI: 6.88–11.43), T. gondii IgA in 1.65% (95%CI: 0.90–3.01) and both T. gondii IgM and IgA in 0.99% (95%CI: 0.45–2.14). The prevalence of IgA antibodies tended to decrease with increasing avidity, from 75% (95%CI: 19.41–99.37) in samples with low avidity to 11.76% (95%CI: 4.44–23.87) in those with high avidity (p = 0.01). Of the study participants who were positive for both T. gondii IgM and IgA antibodies, 66.67% had low or equivocal IgG avidity test results compared to 6.25% who tested positive for IgM, were negative for IgA and in whom low or equivocal IgG avidity test results were noted (p = 0.001). This study indicates that in Western Romania, T. gondii IgG seroprevalence is high in females of reproductive age and T. gondii IgA antibodies may be rarely detected during a serologic screening. However, in individuals with demonstrable T. gondii IgG and IgM antibodies, testing for T. gondii IgA may improve the rate for the detection of a recently acquired toxoplasmosis.