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 na?ve 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.     

Macrophage chemoattractant protein-1 levels in cerebrospinal fluid correlate with containment of JC virus and prognosis of acquired immunodeficiency syndrome-associated progressive multifocal leukoencephalopathy

In the highly active antiretroviral therapy (HAART) era, the role of the inflammatory response in acquired immunodeficiency syndrome (AIDS)-related progressive multifocal leukoencephalopathy (PML) remains controversial. In this study, JC virus DNA load and levels of cytokines were determined in cerebrospinal fluid (CSF) from 32 human immunodeficiency virus (HIV)-1-infected patients with confirmed PML who underwent HAART; cytokines were also measured in 12 HIV-positive controls. Predictors of survival were analyzed by Cox's models. Macrophage chemoattractant protein (MCP)-1 levels were significantly higher in PML patients than in controls (mean +/- SD, 2.45 +/- 0.64 versus 1.32 +/- 0.64 log(10) pg/ml, P<.0001). In PML patients, the higher concentration of MCP-1 correlated with lower JC viral load (r=-.405, P=.036). Higher concentrations of MCP-1 in CSF were associated with longer survival on HAART after adjusting for CD4 counts (for each log(10) pg/ml higher, hazard ratio for death 0.28, 95% confidence interval 0.08--1.00). Predictors of shorter survival were lower baseline CD4 counts, higher JCV DNA concentrations, lower Karnofsky, and no prior HAART exposure. These results showed that higher CSF levels of MCP-1, an inflammatory cytokine, were correlated with better prognosis in HAART-treated patients with PML.     

Potent anti-retroviral therapy with or without cidofovir for AIDS-associated progressive multifocal leukoencephalopathy: extended follow-up of an observational study

To analyze the clinical efficacy of cidofovir combined with highly active anti-retroviral therapy (HAART) in AIDS-related progressive multifocal leukoencepalopathy (PML), a multicenter observational study was performed. Consecutive HIV-positive patients with histologically or virologically proven PML and at least 4 weeks of treatment after diagnosis were examined: 27 patients were treated with HAART, whereas 16 patients were treated with HAART plus cidofovir 5 mg/kg intravenously per week for the first 2 weeks and every other week thereafter. JC virus DNA was quantified in cerebrospinal fluid (CSF) by PCR. Baseline virologic, immunologic, and clinical characteristics as well as HIV RNA and CD4 responses to HAART were homogeneous between the groups. The median follow-up was 132 weeks. In one case (6%), cidofovir was permanently discontinued because of severe proteinuria. One-year cumulative probability of survival was 0.61 with cidofovir and 0.29 without (log rank test P = 0.02). After adjusting for baseline CD4 counts, JC viral load in CSF, Karnofsky, and use of HAART prior to the onset of PML, the use of cidofovir was independently associated with a reduced risk of death (hazard ratio, 0.21, 95% confidence interval, 0.07-0.65; P = 0.005). A randomized study will definitively establish whether cidofovir confers significant advantage over HAART alone in AIDS-related PML.     

Prevalence of neurological complications in Japanese patients with AIDS after the introduction of HAART.

We investigated trends in neurological complications of infection with human immunodeficiency virus (HIV) in Japan after the introduction of highly active antiretroviral therapy (HAART). Two questionnaire surveys were performed in hospitals treating acquired immunodeficiency syndrome (AIDS) to compare two periods: immediately after the introduction of HAART (1999-2001); and a few years later (2002-3). Neurological complications accompanied 15.9% in 1999-2001 and 9.8% in 2002-3. Neurological complications developed without HAART in about 80% of cases. Neurological complications developed as the first AIDS-defining disease for 8.3% of AIDS patients in 1999-2001 and for 5.4% in 2002-3. Prevalences of HIV encephalopathy and myelopathy decreased markedly over the study period, as reported in other developed nations. However, prevalences of cytomegalovirus encephalitis, PML and primary brain lymphoma did not decrease. PML and primary brain lymphoma occurred in patients who received HAART and whose CD4 counts were relatively high during the study period. This is probably related to the extended survival of HIV-infected individuals after the introduction of HAART as a worldwide therapy, and the reactivation of viremia or latent infection persisting within the central nervous system.     

Cytarabine and highly active antiretroviral therapy in HIV-related progressive multifocal leukoencephalopathy

We assessed survival in AIDS-related progressive multifocal leukoencephalopathy (PML) and the effect of cytarabine and antiretroviral therapy in a retrospective analysis of a series of consecutive 35 patients with AIDS-related PML in an academic AIDS referral center over 15 years. Treatment regimens consisted of highly active antiretroviral treatment (HAART), intravenous cytarabine, or both. Median survival after diagnosis in the overall series was 88 days. Patients with low CD4 cell count tended to have shorter survival. Seven patients (20%) had prolonged survival (> 1 year). Cytarabine did not affect survival. Seven patients were treated with HAART, which did not significantly improve survival. We conclude that the prognosis of AIDS-related PML is still poor, with a median survival of 3 months.     

Epidemiology and prognosis of AIDS-associated progressive multifocal leukoencephalopathy in the HAART era

Whereas most AIDS-related neurologic disorders have reduced incidence since HAART therapy was introduced, we find that the incidence of progressive multifocal leukoencephalopathy (PML) did not significantly differ between the pre-HAART and the HAART period (OR 0.78; 95% CI 0.41–1.50). These findings were confirmed by the preliminary results of the Italian Register Investigative Neuro AIDS (IRINA) Study, a prospective multicenter study started in January 2000, which showed that PML was the second most frequently diagnosed neurologic disorder after TE. A similar proportion of cases were found in HAART-naöve and HAART-experienced patients in our experience. PML was more common in the presence of HIV RNA > 500 copies/ml. Most of the cases occurring in HAART-exposed patients developed within the first 6 months of therapy. As others have reported, we find a prolonged survival in PML subjects prescribed HAART (245 days in the group treated with HAART versus 66 days in the group not treated with HAART; P at log rank = 0.001). However despite the survival benefit, AIDS-associated PML still has a serious prognosis. In fact, PML had the lowest 1-year survival probability of any cerebral disorder in our study (P = 0.0005). Our findings also confirm that CSF JCV DNA burden at baseline is a useful prognostic indicator with a threshold of 4.7 log₁₀ JCV copies/ml (P at log rank = 0.01) in our experience. CSF JCV DNA load at 4 weeks of follow-up and clearance of JCV-DNA from CSF are associated with a better neurologic outcome and a longer survival.     

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 > or =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.     

Predictive factors for prolonged survival in acquired immunodeficiency syndrome—associated progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) complicating the acquired immunodeficiency syndrome (AIDS) is typically inexorably progressive with death usually occurring within 6 months of symptom onset. Occasional patients have been observed to survive longer than 1 year, often with remission of clinical features. In this study, we identify predictive factors for prolonged survival in patients with biopsy proven, AIDS-associated PML, by comparing 7 patients with survival exceeding 12 months from symptom onset with 45 patients with shorter survivals. PML was the presenting manifestation of AIDS in 5 (71.4%) of 7 long-term survivors compared with 8 (17.8%) of 45 short-term survivors. CD4 T-lymphocyte counts were substantially higher in the long-term survivors, with 3 (42.9%) of 7 having counts exceeding 300 cells/mm³ in comparison with only 1 (4.3%) of 23 short-term survivors. Contrast enhancement on radiographic imaging was observed in 3 (50%) of 6 long-term survivors in comparison with 4 (8.9%) of 45 short-term survivors. Neurological recovery and radiographic improvement were not observed in any short-term survivors but were seen in 5 (71.4%) long-term survivors. There was no association between treatment modalities and survival. Predictors of long-term survival in AIDS patients with PML include PML as the heralding manifestation of AIDS, high CD4 T-lymphocyte count at disease onset, lesion enhacement on computed tomographic scan or magnetic resonance imaging, and evidence of recovery of neurological function.     

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.     

The evolving face of human immunodeficiency virus-related progressive multifocal leukoencephalopathy: defining a consensus terminology

There is a need for consistent definition of human immunodeficiency virus (HIV)-associated cases of progressive multifocal leukoencephalopathy (PML), especially following the profound disease changes that have resulted from the use of highly active antiretroviral therapy (HAART). According to the criteria used for diagnosis, PML cases should be either referred to as "histology-confirmed," with evidence of JC virus (JCV) infection in brain, "laboratory-confirmed," with detection of JCV DNA in cerebrospinal fluid (CSF), or "possible," in the presence of typical clinical and radiological picture, but no demonstration of JCV infection. Disease outcome should be defined by the evidence or lack of evidence of disease activity, rather than using survival or other variables. Disease activity should be based on clinical (scored neurological examination), radiological (magnetic resonance imaging), and virological (JCV DNA levels in CSF) indicators, to be assessed regularly, e.g., every 3 months until evidence of disease arrest or death. Furthermore, parallel assessments of other HIV-associated manifestations, including CD4+ cell counts and viral load, are required. A standard patient classification would be helpful for clinical management of PML patients, for their inclusion in clinical studies, and also will increase our current knowledge of PML and its evolution in relation with HAART.     

Progressive multifocal leukoencephalopathy--epidemiology, clinical pictures, diagnosis and therapy]

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by the reactivation of a ubiquitous polyomavirus JC (JCV). PML was for many years a rare disease occurring only in patients with underlying severe impaired immunity. Over the past three decades, the incidence of PML has significantly increased related to the AIDS (acquired immunodeficiency syndrome) pandemic and, more recently, to the growing use of immunosuppressive drugs. The clinical presentation of PML is variable with neurological symptoms corresponding to affected cerebral areas. Usually, the clinical outcome of patients with PML is poor with an inexorable progression to death within 6 months of symptom onset. Although PML usually requires a brain biopsy or autopsy for confirmation, radiological imaging and a demonstration of JCV-DNA in the CSF (cerebrospinal fluid) provide supportive evidence for the diagnosis. Although there is no proven effective therapy for PML, patients with HIV (human immunodeficeincy virus)-related PML may benefit significantly from HAART (highly active antiretroviral therapy). In this article the author reviews the epidemiology, especially in Japan, current challenges in the diagnosis and the treatment guidelines of patients with PML based on recent advances in the understanding of the JC virus biology.     

The relative contributions of HAART and alpha-interferon for therapy of progressive multifocal leukoencephalopathy in AIDS

To explore the respective roles of highly active antiretroviral therapy (HAART) and alpha-interferon in improving survival of patients with AIDS-related PML, we retrospectively analyzed all patients with AIDS and PML who were referred to Johns Hopkins University HIV Neurology Program from 1985 to 2000. For 97 evaluable patients, we compared survival of those who were on HAART (three or more antiretroviral drugs) to those who were not on HAART. The effect of alpha-interferon was also studied. Multivariate analysis showed no difference in survival among patients on none, one, or two forms of antiretrovirals; however, survival was significantly greater for those on HAART. Whereas alpha-interferon use was shown to be associated with longer survival (P < 0.057), this effect was not independent of the effects of HAART. HAART significantly increases survival for patients with PML and AIDS; however, alpha-interferon does not appear to provide additional benefit.     

Remission of progressive multifocal leukoencephalopathy following highly active antiretroviral therapy in a patient with HIV infection.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease resulting from lytic infection of oligodendrocytes by the papovavirus JC (JCV). PML has also been recognized as an AIDS-defining illness. The incidence of PML has increased since 1987 and it occurs in up to 4% of patients with AIDS. To date, there is no treatment available for PML and it usually results in death within 3-6 months of diagnosis. However, there are some reports of remission of PML after antiretroviral therapy. We report a 12-year-old child with hemophilia B and developing AIDS with the onset of PML. With highly active antiretroviral therapy, PML subsided with an increase of CD4 count from 10 to 300/microl in spite of about 1.0 X 10(4) human immunodeficiency virus (HIV)-1-RNA copies. He has survived more than 1 year without specific therapy against JCV. Highly active antiretroviral therapy appears to have improved his prognosis in HIV-associated PML.     

The evolving face of human immunodeficiency virus-related progressive multifocal leukoencephalopathy: Defining a consensus terminology

There is a need for consistent definition of human immunodeficiency virus (HIV)-associated cases of progressive multifocal leukoencephalopathy (PML), especially following the profound disease changes that have resulted from the use of highly active antiretroviral therapy (HAART). According to the criteria used for diagnosis, PML cases should be either referred to as “histology-confirmed,” with evidence of JC virus (JCV) infection in brain, “laboratory-confirmed,” with detection of JCV DNA in cerebrospinal fluid (CSF), or “possible,” in the presence of typical clinical and radiological picture, but no demonstration of JCV infection. Disease outcome should be defined by the evidence or lack of evidence of disease activity, rather than using survival or other variables. Disease activity should be based on clinical (scored neurological examination), radiological (magnetic resonance imaging), and virological (JCV DNA levels in CSF) indicators, to be assessed regularly, e.g., every 3 months until evidence of disease arrest or death. Furthermore, parallel assessments of other HIV-associated manifestations, including CD4+ cell counts and viral load, are required. A standard patient classification would be helpful for clinical management of PML patients, for their inclusion in clinical studies, and also will increase our current knowledge of PML and its evolution in relation with HAART.     

Progressive multifocal leukoencephalopathy

Before the AIDS epidemic, progressive multifocal leukoencephalopathy (PML) was a rare disorder occurring most often in association with leukemia and lymphoma. Current estimates indicate that PML ultimately develops in up to 5% of all patients with AIDS. This demyelinating disease results from infection with JC virus, a papova virus, that most of the world's population is exposed to prior to adulthood. Although PML commonly occurs in the setting of advanced immunosuppression, it may be observed in patients with CD4 lymphocyte counts in excess of 200 cells/mm3. Focal neurological symptoms and signs coupled with hyperintense signals abnormalities of the white matter on T2-weighted cranial magnetic resonance imaging are highly suggestive of the disease. In this setting, a positive CSF polymerase chain reaction for JCV DNA has been felt to be sufficiently diagnostic to eliminate the need for brain biopsy. Survival of AIDS-associated PML is poor with median survivals averaging just 6 months. However, as many as 10% of AIDS patients with PML will have prolonged (>12 months) survival and partial recovery. Highly active antiretroviral therapy (HAART) has been demonstrated to have a salutary effect on survival.     

The changing pattern of HIV neuropathology in the HAART era

Highly active antiretroviral treatment (HAART), which has been available for most AIDS patients in France since 1996, has resulted in a dramatic improvement of the progression of the disease. From the survey of our series of 343 brains with acquired immunodeficiency syndrome (AIDS) from patients who died between 1985 and 2002, we found both quantitative and qualitative changes in the pattern of human immunodeficiency virus (HIV) neuropathology. Quantitatively, despite a dramatic decrease in the number of autopsies, brain involvement remained a major cause of death. There was an overall decrease in incidence of cerebral toxoplasmosis, cytomegalovirus encephalitis (CMVE), and HIV encephalitis (HIVE), for which successful treatment is available. This contrasted with the unchanged incidence of progressive multifocal leukoencephalopathy (PML) and malignant non-Hodgkin lymphomas (MNHL). However, when looking closer at the 3 last years, the incidence of diseases affecting patients with severe immunodepression (CMVE, PML, and MNHL) decreased between 2000 and 2002, whereas infections occurring in patients with milder immunodeficiency, toxoplasmosis, varicella-zoster encephalitis (VZVE), or herpes simplex virus encephalitis (HSVE) became more frequent. In addition, we found uncommon types of brain infection such as BK virus encephalitis or general paresis. Finally, we described new variants of HIVE: severe leukoencephalopathy with intense perivascular macrophage and lymphocyte infiltration, possibly due to an exaggerated response from a newly reconstituted immune system, and chronic "burnt out" forms of HIVE as VZVE, toxoplasmosis, or PML, possibly associated with prolonged survival, in which neither inflammation nor organisms could be detected. These findings are compared with those reported in other neuropathological studies from different developed countries.     

Epidemiology of progressive multifocal leukoencephalopathy in the United States: analysis of national mortality and AIDS surveillance data

We analyzed progressive multifocal leukoencephalopathy (PML) mortality data from 1979 to 1987 and data on persons with acquired immunodeficiency syndrome (AIDS) reported to the Centers for Disease Control (CDC). Based on analyses of multiple-cause-of-death vital statistics, deaths related to PML have increased fourfold from 1.5/10,000,000 persons in 1979 to 6.1/10,000,000 persons in 1987. The increase in the PML annual death rate began in 1984, occurred primarily in men 20 to 49 years of age, and was greatest in states known to have a high incidence of AIDS. In 1987, 56% of death certificates that listed PML as a cause of death also listed human immunodeficiency virus (HIV) infection. Analysis of AIDS case reports to the CDC from 1981 through June 1990 demonstrated that 0.72% of persons with AIDS were reported as having PML. Although most persons with AIDS who had PML were 20 to 49 years of age (84.6%), PML was reported more frequently among persons with AIDS greater than or equal to 50 years old than less than 50 years old. In addition, PML was reported more frequently among persons with AIDS who were exposed to HIV by blood transfusion than those in all other exposure categories. These data demonstrate that the increase in PML mortality from 1979 to 1987 was associated with the large increase in immunosuppressed persons with AIDS.     

Progressive multifocal leukoencephalopathy in an HIV patient receiving successful long-term HAART

Progressive multifocal leukoencephalopathy (PML) has been traditionally associated to severe immunosuppression and described mainly in highly active antiretroviral therapy (HAART)-naïve patients with a low lymphocyte CD4+ count. In the last years, some cases of PML have been described in HIV patients with a higher CD4+ count shortly after initiation of HAART and in association with the immune reconstitution inflammatory syndrome (IRIS). We report on a rare case of PML, not IRIS associated, that occurred in a HIV-positive patient with a lymphocyte CD4+ count greater than 700/µl and with an undetectable HIV viral load resulting from a long-term HAART. We describe the pathological and the ultrastructural features of the brain lesion. This case confirms that a severe immunosuppression or an IRIS is not required for the development of PML in HIV positives. The diagnosis of PML should always be considered in patients with consistent neurological symptoms, even with a high lymphocyte CD4+ level and a full viral suppression resulting from a long-term HAART.