Introduction
Infection with Toxoplasma gondii is asymptomatic or mild in immunocompetent people and leads to lifelong immunity, but it can have serious consequences in pregnancy. About five per thousand non-immune pregnant women may acquire toxoplasma infection, with a 10-100% risk of transmission to the baby. Risks of transmission to the baby are higher later in pregnancy, but risks of infection causing harm to the baby are greater earlier in pregnancy.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects on mother and baby of treating toxoplasmosis during pregnancy? What are the effects of treating toxoplasmosis in neonates exposed to toxoplasmosis prenatally? We searched: Medline, Embase, The Cochrane Library and other important databases up to July 2007 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
Results
We found four systematic reviews, RCTs or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
Conclusions
In this systematic review we present information relating to the effectiveness and safety of the following interventions: antiparasitic drugs in pregnancy, antiparasitic drugs in neonates.
Key Points
Infection with Toxoplasma gondii is asymptomatic or mild in immunocompetent people, and leads to lifelong immunity, but it can have serious consequences in pregnancy.
About five per thousand non-immune pregnant women may acquire toxoplasma infection, with a 10-100% risk of transmission to the baby.Infection is usually acquired from undercooked meat, or from fruit and vegetables contaminated with cat faeces.Fetal infection can cause eye and brain damage, growth retardation, and intrauterine death.Risks of transmission to the baby are higher later in pregnancy, but risks of infection causing harm to the baby are greater earlier in pregnancy.Children with subclinical infection at birth may have cognitive, motor, or visual defects that may be difficult to diagnose in early childhood.
We don't know whether treating infected pregnant women with spiramycin, pyrimethamine-sulphonamides, or both reduces the risk of fetal infection, as the few studies that have been done have produced conflicting results.
It is possible that treatment of infection in pregnancy may save the pregnancy without preventing infection, which could increase the prevalence of congenital disease.
We don't know whether antiparasitic drugs, given to neonates who have been infected prenatally, are effective, although there is consensus that infected infants should be treated with pyrimethamine and sulfadiazine for 6 to 12 months.