Toxoplasma gondii.

Toxoplasmosis encompasses a variety of clinical conditions. Serious sequelae are seen in congenital toxoplasmosis and in infections of the immunocompromised host. In the former, prevention of maternal acquisition of toxoplasmosis during pregnancy is paramount. Infection in the compromised host often presents with neurologic abnormalities. Unfortunately, the HIV syndrome itself or other opportunistic infections can present in a similar manner. Often, empiric treatment for toxoplasmosis is begun based on clinical findings and an enhancing lesion noted on the head CT. Pyrimethamine and sulfadiazine remain the drugs of choice for toxoplasmosis and are able to penetrate blood-brain barriers. Currently, trials using other agents are in progress.