Toxoplasmic encephalitis (TE) is among the most common neurologic affections and it is the most prevalent cause of intracerebral mass lesions in AIDS patients. All patients with AIDS hospitalized at the Hospital de Clinicas de Porto Alegre between May/85 and December/91 (516 cases) had their files revised to determinate TE prevalence, serology, sensivity and specificity of the computed tomography (CT) brain scan, clinical findings and serology to make its diagnosis. The prevalence on CT was 13% (presumptive diagnosis). Blood serology and cerebrospinal (CSF) serology to toxoplasma werepositive respectiveiy in 65% and 49%. Autopsies of 125 patients were also revised with a prevalence of 22% (definite diagnosis). CT scan had 65% of sensivity and 82% of specificity. Sensivity and specificity of serology on blood was respectively 95% and 30%, while the cerebrospinal fluid (CSF) serology had 77% of sensivity and 56% of specificity. The following clinical findings were considered: fever (sensivity = 92%; specificity = 56%), neurological focal signs (sensivity = 59% ; specificity = 82%) and headache (sensivity =41 %; specificity = 69%). We conclude that, based on the high serology sensivity and high CT scan specificity, they constitute an useful approach to make TE diagnosis.
Toxoplasmic encephalitis; AIDS; Prevalence