Toxoplasma gondii, PCR

The Toxoplasma gondii, PCR test (Toxoplasma gondii PCR) provides molecular detection of T. gondii and is interpreted alongside standard serologic assays to aid diagnosis of toxoplasmosis. It is used when clinical findings suggest infection and laboratory confirmation is needed. Applications include assessment of suspected infection during pregnancy and detection of disease in immunocompromised patients with compatible manifestations.

Toxoplasma gondii is an obligate intracellular protozoan, with felids as the definitive hosts. Oocysts shed in cat feces require environmental maturation before becoming infectious and can remain viable for months. Humans most often acquire infection by ingesting oocysts from contaminated soil, food, or water, or by consuming tissue cysts in undercooked meat. Less frequent routes include transplacental transmission, organ transplantation, and blood transfusion. Most immunocompetent persons are asymptomatic or develop a mild, self-limited illness. In contrast, immunocompromised hosts may experience severe disease, commonly affecting the central nervous system and the eyes. Maternal infection during pregnancy carries a 30%–40% risk of vertical transmission; earlier gestational infection is associated with miscarriage, stillbirth, or severe neonatal sequelae. Some congenitally infected infants appear asymptomatic at birth but later develop chorioretinitis, hearing loss, or neurodevelopmental delay.