ABSTRACT
BACKGROUND: Characteristics, associated factors, and survival probability of toxoplasmic encephalitis (TE) in the era of advanced highly active antiretroviral therapy (HAART) have not been fully clarified. METHODS: Data for 205 individuals with acquired immunodeficiency syndrome (AIDS)-related TE were derived from the Italian Registry Investigative NeuroAIDS database, and the cases were studied longitudinally to evaluate prevalence, clinical characteristics, and survival. Moreover, the relationship between the occurrence of TE and exposure to antiretroviral therapy and to TE prophylaxis was evaluated. RESULTS: With an overall prevalence of 26%, TE represented the most frequent neurological disorder in the cohort. Female sex, severe immunodeficiency, and absence of primary TE prophylaxis significantly increased the risk of TE, and previous exposure to antiretroviral therapy reduced the probability of disease occurrence. Thirty-six percent of patients who had received antiretroviral therapy developed TE, although in most of these cases, the patient experienced failure of antiretroviral therapy. Of note, 66% of patients who had experienced antiretroviral therapy did not receive prophylaxis for TE at TE diagnosis. The 1-year probability of that infection with human immunodeficiency virus (HIV) would progress or that death would occur after TE was 40% and 23%, respectively. Cognitive symptoms, low CD4(+) cell count, not receiving HAART after TE, and initiating HAART >2 months after TE diagnosis were all significantly associated with an increased probability of progression of HIV infection. Not receiving HAART after diagnosis negatively affected survival. CONCLUSIONS: TE remains a highly prevalent disorder of the central nervous system, even in the late HAART era, particularly among severely immunosuppressed patients and in absence of prophylaxis. Considering that persons with TE have a high probability of early death, prophylaxis should be maintained in immunosuppressed patients who experience failure of antiretroviral therapy, and HAART should be initiated as soon as possible after TE diagnosis.
Subject(s)
Acquired Immunodeficiency Syndrome/complications , Acquired Immunodeficiency Syndrome/drug therapy , Antiretroviral Therapy, Highly Active , Encephalitis/epidemiology , Encephalitis/parasitology , Toxoplasmosis, Cerebral/epidemiology , Acquired Immunodeficiency Syndrome/mortality , Adult , Encephalitis/etiology , Female , Humans , Male , Prevalence , Prognosis , Survival Rate , Toxoplasmosis, Cerebral/etiologyABSTRACT
To evaluate the diagnostic value of thallium-201 single-photon emission computed tomography (201Tl SPECT) in the management of focal brain disorders in the era of highly active antiretroviral therapy (HAART), a validation study of diagnostic procedure was performed in a tertiary clinical care center in Italy. Thirty-eight consecutive HIV-infected patients with neurological impairment and focal brain lesions (FBL) were enrolled in a prospective evaluation and underwent diagnostic procedures according to a standardized protocol based on modified previously released guidelines. Six out of seven PCNSL presented high uptake at 201Tl SPECT [sensitivity 86% (95% CI 42-99); specificity 77% (95% CI 58-90); positive predictive value (PPV) 46% (95% CI 20-74); negative predictive value (NPV) 96% (95% CI 78-100)]. Among toxoplasmic encephalitis (TE) cases 14 showed no uptake and 5 showed an increased uptake [sensitivity 74% (95% CI 49-90); specificity 42% (95% CI 21-66); PPV 56% (95% CI 35-75); NPV 61% (95% CI 32-85)]. Patients taking HAART were more likely to display an increased uptake of 201Tl in the cerebral lesions than patients without HAART (OR 5.07; 95% CI 1.19-21.5). Considering only the patients with diagnosis of TE, 60% of patients who showed high radionuclide uptake were taking HAART, while 79% of patients without relevant uptake were not taking HAART. As a result of the impact of HAART, the diagnostic value of 201Tl SPECT in the management of HIV-associated FBL could be substantially reduced. This observation suggests that in HAART-treated patients, this diagnostic tool be used only when combined with other more specific diagnostic markers.
