Date Published: October 12, 2010
Publisher: Public Library of Science
Author(s): Mario Cortina-Borja, Hooi Kuan Tan, Martine Wallon, Malgorzata Paul, Andrea Prusa, Wilma Buffolano, Gunilla Malm, Alison Salt, Katherine Freeman, Eskild Petersen, Ruth E. Gilbert, Nicholas M. Fisk
Abstract: An observational study by Ruth Gilbert and colleagues finds that prenatal treatment of congenital toxoplasmosis could substantially reduce the proportion of infected fetuses that develop serious neurological sequelae.
Partial Text: Congenital toxoplasmosis occurs when a woman first acquires Toxoplasma gondii infection during pregnancy. Infection can be acquired from oocysts ingested from contaminated soil or water, or tissue cysts from infected meat, but can only reliably be detected by seroconversion (change from negative to positive toxoplasma-specific antibodies) ,. Overall, the proportion of mothers who transmit infection to their fetus averages 25% but increases steeply with the gestational age at maternal seroconversion ,. Congenital toxoplasmosis leads to postnatal clinical manifestations of retinochoroiditis and/or intracranial lesions in one in six (17%) infected infants , and further eye lesions can appear at any age . Less is known about the risk of neurological impairment, even though the main purpose of prenatal screening is to prevent serious neurological sequelae or death (SNSD) . No prospective, comparative studies have evaluated the effectiveness of prenatal treatment for reducing SNSD.
Prenatal treatment substantially reduced the proportion of infected fetuses who developed SNSD. We found no evidence that a pyrimethamine-sulphonamide combination was more effective than spiramycin, which is less toxic . Among infected fetuses, the difference in the proportion of treated and untreated fetuses with SNSD was highest when maternal infection was acquired during the first trimester. These findings should be interpreted with caution because of the low number of the SNSD cases and the uncertainty about the timing of maternal seroconversion. Abnormalities on fetal ultrasound, and intracranial abnormalities detected by cranial ultrasound after birth, were important prognostic markers for SNSD.