[Cerebral toxoplasmosis in patients with human immunodeficiency virus (HIV) infection. Clinico-radiological and therapeutic aspects in 63 patients]

Abstract

We have retrospectively reviewed 63 cases of encephalic toxoplasmosis (ET) in HIV-infected patients in order to determine clinical and radiological characteristics, the diagnostic value of serologic determinations, and the response to antioxoplasmic therapy. ET was the AIDS-defining condition in 44% of the patients. Eighty of the patients had a CD4 cell count < 100/microliters when ET was diagnosed. Only 4.8% of the patients had been taking anti-Pneumocytis carinii prophylaxis with cotrimoxazol. The most frequent clinical presentation was focal neurologic signs in 80.9% of the patients, with headache and fever in 53.3% and 42.4%, respectively. The most frequent cerebral CT finding was hipodense lesions (92%) with ring enhancement (68.9%). They were most frequently had a hemisferic location. Seroconversion was detected in two patients (6%), whereas 55 patients had serologic evidence of latent infection by Toxoplasma gondii (87.3%). Ninety eight percent of the patients were treated with sulphadiazine plus pyrimethamine. However, such therapy should be discontinued in 22% of them and switched to clindamycin plus pyrimethamine. The overall mortality rate during the acute phase of the disease was 7.9%, but 41.4% of the survivors exhibited neurologic sequelae. Relapsing ET was detected in 33.3% of the patients, and it was usually due to discontinuation of treatment. The mean survival time after the diagnosis of ET was 11.5 months. ET is the most common opportunistic infection of the central nervous system among our AIDS patients. Primary prophylaxis for toxoplasmic infection seems advisable in our epidemiologic environment, when CD4 cell count is less than 200/microliters and there is serologic evidence of latent infection. Acute ET usually has a good response to therapy, and the acute mortality rate is low. However, most of the survivors will remain with neurologic sequelae. The high frequency of adverse effects to sulphamide therapy with clindamycin make the need of alternative treatment strategies urgent.