Simona Bossolasco

Clinical epidemiology and survival of progressive multifocal leukoencephalopathy in the era of highly active antiretroviral therapy: Data from the Italian Registry Investigative Neuro AIDS (IRINA)

Human immunodeficiency virus (HIV)-associated progressive multifocal leukoencephalopathy (PML) remains a relevant clinical problem even in the era of highly active antiretroviral therapy (HAART). Aims of the study were to analyze clinical and treatment-related features and the survival probability of PML patients observed within the Italian Registry Investigative Neuro AIDS (IRINA) during a 29-month period of HAART. Intravenous drug use, the presence of focal signs, and the involvement of white matter at neuroradiology increased the risk of having PML. A reduced probability of PML was observed when meningeal signs were reported. Patients starting HAART at PML diagnosis and previously naïve for antiretrovirals showed significantly higher 1-year probability of survival (.58), compared to those continuing HAART (.24), or never receiving HAART (.00). Higher CD4 cell count were associated with a higher survival probability (.45). At multivariate analysis, a younger age, higher CD4, starting HAART at PML diagnosis, the absence of previous acquired immunodeficiency syndrome (AIDS)-defining events, and the absence of a severe neurologic impairment were all associated with a reduced hazard of death. The use of cidofovir showed a trend towards a reduced risk of death.

Cerebrospinal fluid HIV-1 RNA levels: Correlation with HIV encephalitis

Objective:Neuropathological abnormalities induced by HIV-1 are not always predictable on the basis of the presence of HIV-related neurological symptoms. HIV-1 RNA load was measured in the cerebrospinal fluid (CSF) of HIV-infected patients to verify whether it could be a marker of HIV-induced neuropathology. Design and methods:Histopathological and immunohistochemical examination of the brain for HIV-1 p24 antigen was performed in 50 HIV-infected patients with neurological symptoms; patients were defined as having HIV encephalitis in the presence of HIV-related lesions or HIV-1 p24 antigen-positive cells. Quantitative polymerase chain reaction for HIV-1 RNA was retrospectively applied to CSF samples that had been drawn 1–60 days prior to death from these 50 patients; paired plasma samples of 28 patients were also analysed. Results:The CSF HIV-1 RNA copy numbers were significantly higher in 22 patients with HIV encephalitis than in 28 patients without (median, 4.77 log10 versus 3.45 log10 copies/ml; P = 0.0003). No correlation was found between CSF HIV-1 RNA load and the presence of opportunistic brain pathologies at post-mortem examination or between HIV-1 RNA loads in paired CSF and plasma samples. Conclusions:High CSF HIV-1 RNA levels are associated with HIV encephalitis, regardless of the presence of opportunistic brain diseases or HIV-1 RNA levels in plasma. Quantitative CSF HIV-1 RNA may therefore be used as a specific marker of HIV-induced neuropathology.

The effect of highly active antiretroviral therapy-induced immune reconstitution on development and outcome of progressive multifocal leukoencephalopathy: Study of 43 cases with review of the literature

The authors investigated the effect of highly active antiretroviral therapy (HAART) on the onset and outcome of progressive multifocal leukoencephalopathy (PML) in a group of 43 patients with histological or clinicovirological diagnosis of PML. In eight of these cases (19%), PML symptoms presented 21 to 55 days after the start of HAART, concomitantly with a CD4 cell-count increase and plasma human immunodeficiency virus type 1 (HIV-1) RNA load (VL) decrease. Four of these patients died of PML. Apart from baseline VL, we did not identify any other variable that could distinguish these forms of immune reconstitution PML from those occurring in patients either untreated or failing to respond to therapy. To compare the viroimmunological response to HAART with PML outcome, we evaluated a subgroup of 23 patients untreated at the time of PML onset. No different pattern of response to HAART was observed between patients who died or survived to PML. However, start of HAART was delayed of ≥3 months after onset of PML in half of the latter patients. In conclusion, HAART-associated immune reconstitution seems to play a role on development of a substantial number of PML cases. Although the authors could not demonstrate a directly deleterious effect of HAART on PML progression, prompt initiation of HAART after diagnosis of PML and subsequent successful response were often associated with bad PML outcome.

Real-Time PCR Assay for Clinical Management of Human Immunodeficiency Virus-Infected Patients with Visceral Leishmaniasis

ABSTRACT To evaluate the usefulness of a real-time PCR for Leishmania DNA in the diagnosis and follow-up of patients with human immunodeficiency virus type 1 (HIV-1) and Leishmania coinfection, Leishmania DNA levels were measured in whole peripheral blood from 25 HIV-infected patients with clinical features suggestive of visceral leishmaniasis. Leishmania DNA was detected in 10 of 25 patients with microscopically confirmed visceral leishmaniasis and in none of those without this disease. Following treatment with liposomal amphotericin B, a clinical response was observed in 9 of 10 patients, in association with significantly decreased parasite loads. Seven patients relapsed clinically a median of 110 days after the end of treatment, in association with substantial increases in Leishmania DNA levels. Leishmania DNA levels correlated with the clinical course of visceral leishmaniasis, and their measurement at diagnosis and during and after treatment seems to be useful in the clinical management of HIV-infected patients with this disease.

Prevalence, associated factors, and prognostic determinants of AIDS-related toxoplasmic encephalitis in the era of advanced highly active antiretroviral therapy

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.

Highly Active Antiretroviral Therapy and Progressive Multifocal Leukoencephalopathy: Effects on Cerebrospinal Fluid Markers of JC Virus Replication and Immune Response

Cerebrospinal fluid (CSF) samples were examined from 7 patients infected with human immunodeficiency virus type 1 (HIV-1) who had progressive multifocal leukoencephalopathy (PML). Samples were obtained both before and after 35-365 days of highly active antiretroviral therapy (HAART). By polymerase chain reaction, JC virus (JCV) DNA was found in 6 of 7 patients at baseline but in only 1 patient after HAART. In contrast, in 25 historical control patients from whom sequential CSF specimens were obtained, no reversion from detectable to undetectable JCV DNA was observed. By use of enzyme-linked immunosorbent assay, intrathecal production of antibody to JCV-VP1 was shown in only 1 of 4 HAART recipients at baseline but in 5 of 5 patients after treatment. The neuroradiological picture improved or had stabilized in all patients after 12 months of HAART, and all were alive after a median of 646 days (range, 505-775 days). Prolonged survival after HAART for PML is associated with JCV clearance from CSF. JCV-specific humoral intrathecal immunity may play a role in this response.

Progressive Multifocal Leukoencephalopathy (PML) Development Is Associated With Mutations in JC Virus Capsid Protein VP1 That Change Its Receptor Specificity

Progressive multifocal leukoencephalopathy (PML), a fatal demyelinating disease caused by JC virus (JCV) infection of oligodendrocytes, may develop in patients with immune disorders following reactivation of chronic benign infection. Mutations of JCV capsid viral protein 1 (VP1), the capsid protein involved in binding to sialic acid cell receptors, might favor PML onset. Cerebrospinal fluid sequences from 37/40 PML patients contained one of several JCV VP1 amino acid mutations, which were also present in paired plasma but not urine sequences despite the same viral genetic background. VP1-derived virus-like particles (VLPs) carrying these mutations lost hemagglutination ability, showed different ganglioside specificity, and abolished binding to different peripheral cell types compared with wild-type VLPs. However, mutants still bound brain-derived cells, and binding was not affected by sialic acid removal by neuraminidase. JCV VP1 substitutions are acquired intrapatient and might favor JCV brain invasion through abrogation of sialic acid binding with peripheral cells, while maintaining sialic acid-independent binding with brain cells.

Varicella-Zoster Virus (VZV) DNA in Cerebrospinal Fluid of Patients Infected with Human Immunodeficiency Virus: VZV Disease of the Central Nervous System or Subclinical Reactivation of VZV Infection?

To identify varicella-zoster virus (VZV) infections of the nervous system in patients infected with human immunodeficiency virus (HIV), polymerase chain reaction (PCR) analysis of cerebrospinal fluid (CSF) samples from 514 consecutive HIV-infected patients with neurological disease was performed to detect VZV DNA. VZV DNA was detected in CSF of 13 (2.5%) of 514 patients. Four of 13 patients had VZV encephalitis or meningoencephalomyelitis. These four patients received intravenous acyclovir therapy; CSF became negative for VZV DNA and clinical conditions improved for two, whereas CSF remained positive for VZV DNA and clinical conditions worsened until death for two. In nine of 13 patients, the neurological symptoms were likely caused by other simultaneous HIV-related complications in the central nervous system. After intravenous therapy with high doses of acyclovir or foscarnet, VZV was cleared from CSF in eight of nine patients. VZV DNA can be detected in CSF of HIV-infected patients in association with either manifestations of neurological VZV disease or subclinical reactivation of VZV infection. Antiviral treatment may be effective in suppressing VZV replication in the nervous system.

Epstein-Barr virus DNA load in cerebrospinal fluid and plasma of patients with AIDS-related lymphoma

Detection of Epstein-Barr virus (EBV) DNA in the cerebrospinal fluid (CSF) is associated with acquired immunodeficiency syndrome (AIDS)-related brain lymphoma. Real-time polymerase chain reaction (PCR) was performed to quantify EBV DNA in CSF and plasma from 42 patients with AIDS-related non-Hodgkin’s lymphoma (NHL). Twenty patients had primary central nervous system lymphoma (PCNSL) and 22 systemic NHL, including 12 with central nervous system involvement (CNS-NHL). As controls, 16 HIV-infected patients with other CNS disorders were examined. EBV DNA was detected in the CSF from 16/20 (80%) patients with PCNSL, 7/22 (32%) with systemic NHL, 8/12 (67%) with CNS-NHL, and 2/16 (13%) of the controls. The viral EBV DNA levels were significantly higher in the CSF from patients with PCNSL or CNS-NHL compared to patients with systemic NHL or controls. EBV DNA was detected in plasma from 5/16 (31%) patients with PCNSL, 9/16 (56%) with systemic NHL, 4/9 (44%) with CNS-NHL, and 4/15 (27%) controls. No difference in plasma viral load was found between patient groups. From the patients with CNS-NHL, plasma samples drawn prior to CNS involvement contained significantly higher EBV DNA levels than those from systemic NHL patients without subsequent CNS involvement. EBV DNA levels in the CSF, but not in plasma, from patients treated with antiherpes drugs were significantly lower than in untreated patients. High CSF EBV DNA levels were found in HIV-associated brain lymphomas and the viral load can be clinically useful. High plasma EBV DNA levels might predict CNS involvement in systemic NHL.

Molecular analysis of cerebrospinal fluid in viral diseases of the central nervous system

Abstract The use of nucleic acid (NA) amplification techniques has transformed the diagnosis of viral infections of the central nervous system (CNS). Because of their enhanced sensitivity, these methods enable detection of even low amounts of viral genomes in cerebrospinal fluid. Following more than 10 years of experience, the polymerase chain reaction or other NA-based amplification techniques are nowadays performed in most diagnostic laboratories and have become the test of choice for the diagnosis of several viral CNS infections, such as herpes encephalitis, enterovirus meningitis and other viral infections occurring in human immunodeficiency virus-infected persons. Furthermore, they have been useful to establish a viral etiology in neurological syndromes of dubious origin and to recognise unusual or poorly characterised CNS diseases. Quantitative methods have provided a valuable additional tool for clinical management of these diseases, whereas post-amplification techniques have enabled precise genome characterisation. Current efforts are aiming at further improvement of the diagnostic efficiency of molecular techniques, their speed and standardisation, and to reduce the costs. The most relevant NA amplification strategies and clinical applications of to date will be the object of this review.