Treatment outcomes for gestational toxoplasmosis in India with an emphasis on periconceptional infection in a prospective study

Congenital toxoplasmosis (CT) may lead to severe foetal complications when Toxoplasma gondii infection is acquired during pregnancy. This prospective study-the first of its kind from India-investigated serological responses in 340 antenatal women, focusing on infection timing, particularly the periconceptional period, and assessed treatment outcomes in acute gestational toxoplasmosis. Diagnosis of gestational toxoplasmosis was based on combined IgM and IgG ELISA with IgG avidity testing to confirm acute infection; treatment of presumptive positive cases was initiated on spiramycin. Amniocentesis, being an invasive and risky technique, was done only in patients with abnormal ultrasound findings and positive serology. Confirmation of CT was done by positive quantitative PCR (qPCR) on amniotic fluid, and patients were switched to pyrimethamine and sulfadiazine. PCR was also used to test placental tissue from these patients at the time of delivery. All mothers and neonates were followed up for one year postpartum. Serological screening identified gestational toxoplasmosis in (35/340), 10.29% of participants, who were started on spiramycin. Of the 16 patients who underwent amniotic fluid PCR, 6 tested positive; therefore, 6/340(1.7%) had confirmed congenital toxoplasmosis. Out of these 4 (66.6%) pregnancies resulted in liveborn infants who remained asymptomatic with no clinical, serologic evidence of congenital toxoplasmosis during 12-month follow-up, while 2 (33.3%) pregnancies with PCR-confirmed CT ended in mid-trimester loss. Additionally, 2.05% acquired acute toxoplasmosis during the periconceptional period, identified through serology. These findings underscore the importance of early diagnosis and timely therapeutic intervention in gestational toxoplasmosis to reduce the risk of congenital transmission and improve foetal outcomes.