Early prenatal diagnosis of congenital toxoplasmosis using amniotic fluid samples and tissue culture.

The presence of Toxoplasma gondii in amniotic fluid was demonstrated using tissue culture in four of nine cases of congenital toxoplasmosis, whereas Toxoplasma gondii antigen was undetectable using a sensitive enzyme immunoassay technique. Parasites were identified in monolayers four days after inoculation using an indirect immunofluorescence assay. Since tissue culture may provide evidence of infection within a few days, this method is proposed for early prenatal diagnosis of congenital toxoplasmosis.