TABLE 3

Treatment of acute toxoplasmosis in pregnant women and newborns

Infection stageRegimenComments
Maternal infection at <14 weeks of gestation, no fetal infectionSpiramycin (1 g [3 million units] every 8 h until delivery)Spiramycin is not effective for treating established fetal infection and hence should be used only for prevention of vertical transmission
Amniocentesis and fetal ultrasound should be performed when feasible to rule out fetal infection
Maternal infection at >14 weeks of gestationaPyrimethamine (100 mg daily for 2 days and then 50 mg daily) plus sulfadiazine (1 g q8h [body wt of <80 kg] or 1 g q6h [body wt of ≥80 kg]) plus folinic acid (10–20 mg daily pending fetal USG and amniocentesis)Pyrimethamine is teratogenic and should not be used in early pregnancy
If fetus is confirmed to be infected (abnormal USG and/or positive amniotic fluid PCR), continue pyrimethamine plus sulfadiazine plus folinic acid until deliverySerial fetal USG and amniotic fluid PCR should be performed at 18 weeks of gestation
If fetus is not infected (e.g., negative USG and amniotic fluid PCR), pyrimethamine plus sulfadiazine plus folinic acid may be switched to spiramycin
Alternatively, pyrimethamine plus sulfadiazine plus folinic acid can be continued until delivery or alternated with spiramycin on a monthly basis
Congenital infection in newbornsPyrimethamine (1 mg/kg q12h for 2 days and then 1 mg/kg/day for 2–6 mo and then 1 mg/kg/day 3 times a week) plus sulfadiazine (50 mg/kg q12h) plus folinic acid (10 mg 3 times a week)Treatment should be started as soon as feasible after birth and continued for at least 1 year
  • a The 14-week cutoff period for starting pyrimethamine and sulfadiazine in pregnant women may vary in different countries.