Clinical manifestations may mimic those of other opportunistic infections. Necrotizing encephalitis, pneumonitis, and myocarditis are the most common autopsy findings. The most frequent clinical findings reflect involvement of these 3 organ systems, although disseminated toxoplasmosis is being described with increasing frequency. Incidence of toxoplasmic encephalitis in patients with AIDS is correlated directly with the presence of antitoxoplasmal antibodies. In patients with AIDS, CNS involvement is the mostcommon manifestation, ranging from nonspecific, generalized symptoms to focal findings such as headache, altered levels of consciousness, motor impairment, and seizures.
Pulmonary involvement is the second most common manifestation.
Clinically, patients may appear to have tuberculosis or infection with Pneumocystis carinii. Although the rate of seropositivity for T gondii is high, clinical manifestation of the disease is relatively rare. In adults, multiple organ involvement is extremely serious, but no data are available on mortality rates. In patients with AIDS, untreated toxoplasmic encephalitis is uniformly fatal. Prevalence of seropositivity for T gondii increases with age.