Diagnosis -- Disseminated Toxoplasmosis

Abstract

Infections due to the protozoan parasite Toxoplasma gondii are highly prevalent among humans and animals throughout the world. Acquired infections in immunocompetent individuals are generally asymptomatic or associated with lymphadenopathy and a flu-like illness. Congenital toxoplasmosis in infants results from an acute primary infection acquired by the mother during pregnancy. The incidence and severity of congenital toxoplasmosis vary with the trimester during which the infection was acquired. Ocular toxoplasmosis, an important cause of chorioretinitis and blindness, is frequently a result of congenital infection. Prompt recognition and treatment of toxoplasmosis during pregnancy can reduce the sequelae of central nervous system (CNS) and ocular involvement in infants. Figure 1 Patients receiving steroids or other immunosuppressive drugs are especially prone to develop disseminated toxoplasmosis, either from acute exposure to the organisms or from reactivation of latent infection. Multiple organ systems are often involved, including the CNS, heart, lungs and skeletal muscle. The diagnosis of toxoplasmosis is readily made from histologic analysis of tissue specimens by observing any of the three infectious stages of T. gondii: tachyzoites in groups, bradyzoites (tissue cysts) or sporozoites within oocysts. Figure 2