Medical Diagnosis Exams

Toxoplasmosis is a common infection caused by the protozoan parasite Toxoplasma gondii. The infection is mainly acquired by ingestion of food or water that is contaminated by mature oocysts shed by cats or by undercooked meat containing tissue cysts. Primary, acute infection which is mostly mild or even asymptomatic in healthy individuals, is followed by a latent infection which usually persists for life. Primary maternal Toxoplasma infection occurring during pregnancy may lead to severe damage of the fetus as the parasite can be transmitted across the placenta. The fetal infection rate increases with gestational age. However, the risk of severe clinical manifestations is higher in case of early maternal infection. Early drug therapy in acute infection during pregnancy can prevent congenital damage or ameliorate the severity of clinical manifestations. The diagnosis of Toxoplasma infection is most commonly made by the detection of anti‑Toxoplasma‑specific IgG and IgM antibodies. The IgG avidity test was developed to help discriminate between past and recently acquired infection.