Clinical course and prognostic factors of progressive multifocal leukoencephalopathy in patients treated with highly active antiretroviral therapy

Long-term outcome of natalizumab-associated progressive multifocal leukoencephalopathy in Austria: a nationwide retrospective study

BACKGROUND/OBJECTIVE

The use of natalizumab (NAT) in multiple sclerosis (MS) may be complicated by progressive multifocal leukoencephalopathy (PML), a rare and life-threatening opportunistic brain infection. We aimed to analyze the course of MS after PML recovery together with the long-term outcome of NAT-associated PML (NAT-PML) in Austria.

METHODS

Retrospective study based on identification of cases in the nationwide Austrian MS treatment registry (AMSTR) and MS centers with review of patient records. The expanded disability status scale (EDSS) was used to measure neurological disability and outcome.

RESULTS

As of December 2022, we identified 15 NAT-PML cases in Austria; only 20% occurred after 2016, when increased vigilance commenced. Two patients did not survive acute PML, and an additional patient died five years later, yielding a mortality rate of 20%. Seizures occurred exclusively in patients with pronounced EDSS increase. Gadolinium (Gd)-enhancement on brain magnetic resonance imaging (MRI) on PML suspicion was associated with minor changes of post-PML neurological disability. Long-term follow-up of up to 132 months (median 76 months) was available in 11/15. The overall median EDSS increased from 3.5 at pre-PML to 6.5 at the last assessment. Regarding inflammatory MS-related disease activity during the observation period, one single individual experienced an MS relapse and another patient had two Gd-enhancing brain lesions. Three patients converted to progressive MS within three years from PML and the EDSS further increased in 6/11.

CONCLUSIONS

The number of NAT-PML cases is decreasing over time. While many patients accumulated severe persistent neurological deficits compared to pre-PML, inflammatory MS-related disease activity after PML recovery was rare.

Survival and prognostic factors of progressive multifocal leukoencephalopathy in people living with HIV in modern ART era

Background

The incidence of progressive multifocal leukoencephalopathy (PML) in people living with HIV (PLWH) is 2%-4%. Currently, there is no effective therapeutic strategy for the treatment of PML in PLWH, resulting in a mortality of up to 50%. This study aimed to identify risk factors of death and prognostic markers in people living with HIV with PML.

Methods

A retrospective cohort study of AIDS-related PML individuals was conducted from January 1, 2015, to October 1, 2022, in Shanghai, China. PLWH who were diagnosed with PML for the first time were included. Kaplan-Meier curve and Cox regression were used to analyze the survival and its predictors. Levels of inflammatory markers and immune checkpoint inhibitors in blood and cerebrospinal fluid (CSF) were measured in the prestored samples using bead-based multiplex assay Indolamine 2,3-dioxygenase was determined using ELISA.

Results

Twenty of 71 subjects had initiated antiretroviral therapy (ART) before PML onset and no patients discontinued ART during this period. In total, 34 patients (47.9%) had opportunistic infections (OIs), the median CD4+ T cell count was 73.0 (33.0-149.0) cells/μL. The estimated probability of survival at six months was 78% (95% confidential intervals [CIs]:0.63-0.85). OIs, low CD4+ T cell count were associated with lower estimated six-month survival (hazard ratio 8.01, 95% CIs: 1.80-35.00, P=0.006 and 5.01, 95% CIs:1.57-16.03, p=0.007). Indolamine 2,3-dioxygenase activity in CSF of non-survivors group were higher than survivors group (p<0.05).

Conclusions

The survival rate of AIDS-related PML in the modern ART era was higher than the survival rate a decade ago. Low CD4+T cell count, OIs, were all associated with death of individuals with AIDS-related PML. The role of IDO in AIDS-related PML warrant further investigation.

Sequelae and mortality in patients with HIV/AIDS and Progressive Multifocal Leukoencephalopathy: Systematic review and case series in the Brazilian Amazon

Background

Progressive Multifocal Leukoencephalopathy (PML) is an opportunistic neurological disease that mainly affects individuals with HIV/AIDS and has high morbidity and mortality, due to its demyelinating characteristic. This co-infection has been reported since the begging of HIV/Aids epidemic with increasing unfavorable outcomes, however, factors associated to sequelae and death are greatly unknown. In this study we aimed to understand factors associated with the main outcomes of individuals diagnosed with PML and HIV/AIDS, in addition to reporting the characteristics of patients presenting to a referral center in infectious diseases in the Brazilian Amazon.

Methods

A systematic review was performed until July 2022, following the PRISMA guidelines, at Medline/Pubmed, Web of Science, Lilacs and Scielo databases using combinations of HIV, Aids, JC Virus and Progressive Multifocal Leukoencephalopathy, with no restriction to publication date. Additional cases, meeting the eligibility criteria, were added from our hospital database, which consisted of patients presenting PML/HIV between 2010 and 2022. A meta-analysis aiming to explore factors associated to sequelae and death was performed. Baseline characteristics were described using mean and standard deviation, or median and interquartile range when appropriate; multivariate analysis was performed to study factors associated to death and sequelae outcomes.

Results

Eighteen patients were diagnosed between 2010 and 2022, of these, 10 had positive PCR for JC virus. In the Systematic Review, 216 studies yielded 235 confirmed cases of co-infection. A total of 245 were included for analysis. The rates of death and sequelae were, respectively, 47.1% (114/242) and 41.2% (54/131). The use of antiretroviral therapy was more associated with a lower chance of death (OR 0.30, 95% CI: 0.11-0.83), while muscle weakness (OR 4.82, 95% CI: 2.07-11.21) and muscle spasms (OR 6.12, 95% CI: 1.05-35.76) were associated with greater chances of sequelae.

Conclusion

Those on antiretroviral therapy appear to be less likely to die, and among those who survive, those who have muscle weakness as a symptom on admission are more likely to develop sequelae. Adherence to ART, as well as a comprehensive clinical evaluation and follow-up may help to improve clinical outcomes and awareness of morbidities.

Study of clinical profile and outcomes in progressive multifocal leukoencephalopathy in acquired immunodeficiency syndrome patients in the highly active antiretroviral therapy era - An observational study

Background and Objectives

Progressive multifocal leukoencephalopathy (PML) is a viral infection affecting the central nervous system (CNS) seen mostly in advanced human immunodeficiency virus (HIV) infection. There is limited data on the epidemiology and disease course of these patients from India. This study was aimed to determine the frequency of PML in patients with HIV/acquired immunodeficiency syndrome (AIDS) and the clinical presentation and prognosis of these patients.

Materials and Methods

The study was conducted at a tertiary care HIV center in New Delhi. Data of 765 patients from our anti-retroviral therapy (ART) clinic during a span of 4 years were retrospectively analyzed and reviewed. The diagnosis was based on the clinical and radiological picture and exclusion of other differential diagnosis by cerebrospinal fluid and serological studies.

Results

Of 765 patients with HIV/AIDS, 12 (1.56%) were diagnosed with PML on the basis of consistent clinical and radiological features after ruling out other differential diagnosis. PML was the initial presentation of HIV infection in 8 (55.5%) patients. 11 (89%) patients had CD4 count <200/μl. Insidious onset focal limb weakness (50%) and dysarthria (50%) were common symptoms. Magnetic resonance imaging of the brain revealed characteristic white matter lesions in all the patients. The estimated median survival was 40 months (95% confidence interval, 23.88-53.19 months).

Interpretation and Conclusions

Our results show that PML is associated with high morbidity despite the institution of highly active ART (HAART), but mortality has significantly declined if ART is started early. Key to good response is early diagnosis and HAART.

Off the Shelf Third Party Virus Specific T-Cell Therapy to Treat JC Polyomavirus Infection in Hematopoietic Stem Cell Transplant Recipients

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) is a progressive and generally fatal demyelinating neurological disease that occurs in profoundly immunocompromised patients due to infection with the human polyomavirus JC virus (JCPyV). Treatment options are limited and are largely focused on restoring T-cell immunity and outcomes are historically poor. Control of JCPyV in the setting of an immunocompromised patient by adoptive transfer of third-party virus specific T-cells (VSTs) has been described in a small number of cases.

OBJECTIVE

To investigate treatment response and outcomes in recipients of hematopoietic stem cell transplant (HSCT) with PML treated with third-party VSTs directed against BK virus, a highly homologous polyoma virus that shares immunogenic epitopes with JCPyV.

STUDY DESIGN

Retrospective chart review was performed on four patients who received VSTs for the treatment of PML at Cincinnati Children's Hospital Medical Center since 2019 RESULTS: VSTs were safely administered with no cases of graft-vs-host disease and no infusion reactions. One patient, who was treated almost immediately after diagnosis, was able to clear JCPyV from blood and CSF with resultant stabilization of neurologic decline. Interferon-gamma ELISpot demonstrated virus specific T-cells in the peripheral blood following infusion. Response was maintained through repeat infusions. Three other patients, all of whom had a longer delay between diagnosis and infusion, had progressive neurologic decline despite varying degree of improvement in viral load.

CONCLUSION

PML is a rare but often fatal complication following HSCT for which few treatment options are available. BK directed, JCPyV cross-reactive VSTs are a safe and viable therapeutic option and prompt administration should be considered after a diagnosis of PML is made. Key points • Virus specific T cells targeting JCPyV virus are safe with no infusional toxicity or de-novo graft versus host disease. • Virus specific T-cells have evidence of efficacy in some cases of PML, but further studies are needed to determine factors that will optimize response.

Grey matter abnormality in progressive multifocal leucoencephalopathy

Progressive multifocal leucoencephalopathy (PML) is a demyelinating white matter disease that most often affects immunocompromised people infected by JC virus. The diagnostic gold standard is demonstrable viral DNA or protein from histopathological tissue. However, there are few detailed descriptions of cortical grey matter involvement on neuroimaging. Here we describe the histopathological correlate of cerebral grey matter involvement and radiological accompaniment in a patient with biopsy proven PML.

Targeted metabolomic profiling of cerebrospinal fluid from patients with progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML), caused by JC polyomavirus, is a demyelinating disease of the central nervous system that primarily affects oligodendrocytes. It can cause significant morbidity and mortality. An early diagnosis is of high relevance as timely immune reconstitution is essential. However, diagnosis can be challenging if virus detection via cerebrospinal fluid (CSF) PCR remains negative. Hence, identifying CSF biomarkers for this disease is of crucial importance. We applied a targeted metabolomic screen to CSF from 23 PML patients and eight normal pressure hydrocephalus (NPH) patients as controls. Out of 188 potentially detectable metabolites, 48 (13 amino acids, 4 biogenic amines, 1 acylcarnitine, 21 phosphatidylcholines, 8 sphingolipids, and the sum of hexoses) passed the quality screen and were included in the analyses. Even though there was a tendency towards lower concentrations in PML (mostly of phosphatidylcholines and sphingomyelins), none of the differences between PML and controls in individual metabolite concentrations reached statistical significance (lowest p = 0.104) and there were no potential diagnostic biomarkers (highest area under the ROC curve 0.68). Thus, CSF metabolite changes in PML are likely subtle and possibly larger group sizes and broader metabolite screens are needed to identify potential CSF metabolite biomarkers for PML.

Fifty Years of JC Polyomavirus: A Brief Overview and Remaining Questions

In the fifty years since the discovery of JC polyomavirus (JCPyV), the body of research representing our collective knowledge on this virus has grown substantially. As the causative agent of progressive multifocal leukoencephalopathy (PML), an often fatal central nervous system disease, JCPyV remains enigmatic in its ability to live a dual lifestyle. In most individuals, JCPyV reproduces benignly in renal tissues, but in a subset of immunocompromised individuals, JCPyV undergoes rearrangement and begins lytic infection of the central nervous system, subsequently becoming highly debilitating-and in many cases, deadly. Understanding the mechanisms allowing this process to occur is vital to the development of new and more effective diagnosis and treatment options for those at risk of developing PML. Here, we discuss the current state of affairs with regards to JCPyV and PML; first summarizing the history of PML as a disease and then discussing current treatment options and the viral biology of JCPyV as we understand it. We highlight the foundational research published in recent years on PML and JCPyV and attempt to outline which next steps are most necessary to reduce the disease burden of PML in populations at risk.

Neuroimaging Insights Into Early Stages of HIV-Progressive Multifocal Leukoencephalopathy: A Case Report

This report aims to enhance the understanding of early longitudinal neuroimaging features of progressive multifocal leukoencephalopathy (PML) in human immunodeficiency virus (HIV). Neuroimaging has become crucial in the diagnosis and early recognition of PML. Recognition of magnetic resonance imaging (MRI) features in the early stages of PML is paramount to avoid misdiagnosis and facilitate the delivery of treatments aimed at reducing disease progression. A 49-year-old white man with HIV presented with 4-month progressive left-sided weakness. Neurological examination revealed mild cognitive impairment, left-sided hemiparesis, and somatosense impairment to all modalities. Brain MRI revealed a punctate pattern with innumerable T2-FLAIR (fluid attenuated inversion recovery) hyperintensities in the cortex, brainstem, cerebellum, subcortical, and periventricular areas. Susceptibility-weighted imaging (SWI) revealed hypointensities involving subcortical U-fibers and cortical architecture. A comprehensive diagnostic evaluation was inconclusive. John Cunningham virus (JCV) PCR in cerebrospinal fluid (CSF) was indeterminate. He was started on antiretroviral therapy. Repeat brain MRI performed 1.5 months later, in the setting of further neurological decline, demonstrated progression of the T2-hyperintensities into a large confluent white matter lesion in the right frontoparietal lobe. Despite an indeterminate JCV PCR, the appearance and characteristic progression of the lesions in successive imaging in the setting of severe immunosuppression, with extensive negative infectious workup, was indicative of PML. This clinical experience illustrates unique neuroimaging features of HIV-PML in early stages and its progression over time. It especially highlights the relevance of the SWI sequence in the diagnosis and features observed with disease evolution. Short-term imaging follow-up may assist with the recognition of MRI features consistent with the biology of the infection.

A controlled inflammation and a regulatory immune system are associated with more favorable prognosis of progressive multifocal leukoencephalopathy

OBJECTIVE

In the present study, we analyzed the inflammatory profiles of brain tissues obtained from patients with progressive multifocal leukoencephalopathy (PML) due to John Cunningham (JC) virus infection to identify potential prognostic factors.

METHODS

The study included seven patients (two men, five women) who had been pathologically diagnosed with PML, and all of whom were HIV negative. Fixed brain samples were analyzed via hematoxylin and eosin (HE) staining and Klüver-Barrera (KB) staining. We then performed immunohistochemistry (IHC) specific to JC virus capsid proteins (VP1 and VP2/3) and lymphocyte surface markers (CD4, CD8, CD138, and PD-1).

RESULTS

The mean age at onset was 53.4, while the mean duration until biopsy/autopsy was 4.7 months. Four patients were included in the good prognosis (GP) group, while three were included in the poor prognosis (PP) group. Pathological analysis revealed a significantly larger number of CD4-positive T-cell infiltrations (P = .029) in the GP group, along with a preserved CD4:CD8 ratio. Larger numbers of CD138-positive plasma cells were also observed in the GP group (P = .029) than in the PP group. Linear regression analyses revealed a significant association between the numbers of CD138-positive plasma cells and PD-1-positive cells (R² = 0.80).

CONCLUSIONS

Viral loads in the cerebrospinal fluid, a controlled inflammatory response mediated by CD4- and CD8-positive T cells, and plasma cells are associated with PML prognosis. Our findings further indicate that regulatory plasma cells may regulate inflammatory T-cell activity via a PD-1/PD-L1 immuno-checkpoint pathway, thereby protecting the uninfected brain from excessive immune-mediated damage during an active JC virus infection.

Treatment of Progressive Multifocal Leukoencephalopathy With Mirtazapine

BACKGROUND AND OBJECTIVES

Progressive multifocal leukoencephalopathy (PML) is a rare, JC-virus-mediated, demyelinating disease with a high mortality rate. As no recommended treatment exists, mirtazapine, a potential blocker of virus entry into cells, has been empirically used.

METHODS

We analysed existing data on mirtazapine's efficacy to treat PML by systematically reviewing the literature since 2005, when it was first used.

RESULTS

Searches in PubMed, EBSCO, SCOPUS and Google Scholar between January 2005 and December 2015, identified five cohort studies and 74 case reports. No statistically significant effect of mirtazapine on PML outcome was observed in the cohort studies. From studying the case reports, mortality rate for PML was associated with the underlying circumstances, such as an older age, the use of an immunosuppressant, or PML occurring in patients with a haematological malignancy or a transplant.

CONCLUSIONS

Except for natalizumab-associated PML, we did not highlight any potential benefit of mirtazapine on disease outcomes. Further interventional studies are needed to confirm that 5-HT2AR inhibition is relevant to treat PML.

Neurosurgery and human immunodeficiency virus in the era of combination antiretroviral therapy: a review

Human immunodeficiency virus (HIV) is a global health problem. It renders the central nervous system susceptible to infectious and noninfectious diseases. HIV-positive individuals may present to neurosurgical services with brain lesions of unknown etiology. The differential diagnosis in these cases is broad, including opportunistic infections and malignancies, and investigation should be tailored accordingly. Opportunistic infections of the central nervous system can be complicated by hydrocephalus, and the management is pathogen dependent. Patients may also present to a neurosurgical service with conditions unrelated to their HIV status. This review outlines important conditions that cause brain lesions and hydrocephalus. It addresses the issues of diagnosis and intervention in HIV-positive patients in the era of combination antiretroviral therapy, while not ignoring the potential for opportunistic central nervous system infection in undiagnosed patients. The care of HIV-positive patients presenting to neurosurgical services requires a multidisciplinary approach, which is reflected in the authorship of this review, as well as in the guidance given.

Prevention and treatment of opportunistic infections and other coinfections in HIV-infected patients: May 2015

Despite the huge advance that antiretroviral therapy represents for the prognosis of infection by the human immunodeficiency virus (HIV), opportunistic infections (OIs) continue to be a cause of morbidity and mortality in HIV-infected patients. OIs often arise because of severe immunosuppression resulting from poor adherence to antiretroviral therapy, failure of antiretroviral therapy, or unawareness of HIV infection by patients whose first clinical manifestation of AIDS is an OI. The present article updates our previous guidelines on the prevention and treatment of various OIs in HIV-infected patients, namely, infections by parasites, fungi, viruses, mycobacteria, and bacteria, as well as imported infections. The article also addresses immune reconstitution inflammatory syndrome.

Cellular immunotherapy for patients with reactivation of JC and BK polyomaviruses after transplantation

Immunosuppression of patients after hematopoietic stem cell or kidney transplantation potentially leads to reactivation of JC and BK polyomaviruses. In hematopoietic stem cell transplantation, the reactivation rate of BKV can be up to 60%, resulting in severe complications of the urogenital tract, particularly hemorrhagic cystitis and renal dysfunction. After kidney transplantation, BKV reactivation can cause a loss of the graft. JCV can cause progressive multifocal leukoencephalopathy, a lethal disease. Adoptive transfer of donor-derived polyomavirus-specific T cells is an attractive and promising treatment that restores virus-specific cellular immunity. Pioneering work in the early 1990s on the reconstitution of cellular immunity against cytomegalovirus and recent development in the field of monitoring and isolation of antigen-specific T cells paved the way toward a personalized T-cell therapy. Multimer technology and magnetic beads are available to produce untouched T cells in a single-step, good manufacturing practice-compliant procedure. Another exciting aspect of T-cell therapy against polyomaviruses is the fact that both JCV and BKV can be targeted simultaneously because of their high sequence homology. Finally, "designer T cells" can be redirected to recognize polyomavirus antigens with high-affinity T-cell receptors. This review summarizes the state-of-the art technologies and gives an outlook of future developments in the field.

Progressive multifocal leukoencephalopathy in pediatric patients: case report and literature review

Progressive multifocal leukoencephalopathy is a rare, demyelinating disease of the central nervous system caused by JC virus. Fewer than 30 cases have been reported in HIV- and non-infected children. We report the case of a 15-year-old girl with progressive multifocal leukoencephalopathy and AIDS who presented with nystagmus, dysarthria and ataxia. Following combined antiretroviral therapy, she developed immune reconstitution inflammatory syndrome, which proved fatal.

Therapy and prophylaxis of opportunistic infections in HIV-infected patients: a guideline by the German and Austrian AIDS societies (DAIG/ÖAG) (AWMF 055/066)

INTRODUCTION

There was a growing need for practical guidelines for the most common OIs in Germany and Austria under consideration of the local epidemiological conditions.

MATERIALS AND METHODS

The German and Austrian AIDS societies developed these guidelines between March 2010 and November 2011. A structured Medline research was performed for 12 diseases, namely Immune reconstitution inflammatory syndrome, Pneumocystis jiroveci pneumonia, cerebral toxoplasmosis, cytomegalovirus manifestations, candidiasis, herpes simplex virus infections, varizella zoster virus infections, progressive multifocal leucencephalopathy, cryptosporidiosis, cryptococcosis, nontuberculosis mycobacteria infections and tuberculosis. Due to the lack of evidence by randomized controlled trials, part of the guidelines reflects expert opinions. The German version was accepted by the German and Austrian AIDS Societies and was previously published by the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF; German Association of the Scientific Medical Societies).

CONCLUSION

The review presented here is a translation of a short version of the German-Austrian Guidelines of opportunistic infections in HIV patients. These guidelines are well-accepted in a clinical setting in both Germany and Austria. They lead to a similar treatment of a heterogeneous group of patients in these countries.

A Rare Case of Immune Reconstitution Inflammatory Syndrome Development in an Immunocompromised Patient with Progressive Multifocal Leukoencephalopathy and Multicentric Castleman's Disease

Immune reconstitution inflammatory syndrome (IRIS) development in HIV with preexistent progressive multifocal leukoencephalopathy (PML) has been extensively studied. PML-IRIS typically manifests clinically as new or worsening neurologic symptoms in conjunction with enlarging CNS lesions and occurs in approximately 10–20 percent of HIV-infected patients with PML who begin HAART. Likewise, Multicentric Castleman's Disease (MCD), a rare malignant lymphoproliferative disorder, has a strong and well-known association with HIV. Our case provides a rare instance of PML-IRIS in combination with MCD in an HIV-positive individual. The combination of all three diseases has never been reported in the literature. Both MCD and PML were present during initial determination of HIV infection in our patient and their disease courses were altered during the subsequent development of IRIS.

Continued declining incidence and improved survival of progressive multifocal leukoencephalopathy in HIV/AIDS patients in the current era

To evaluate the situation and perspectives of progressive multifocal leukoencephalopathy (PML) in human immunodeficiency virus (HIV)-infected patients, we investigated changes in the incidence, causes, and long-term outcome of this disease in 72 acquired immunodeficiency syndrome (AIDS) patients who were diagnosed with PML from 1996 to 2011. Patients were classified according to the date of diagnosis in the first (1996-2000, n = 35), second (2001-2006, n = 26), and recent or third highly active antiretroviral therapy (HAART) period (2007-2011, n = 11). Overall, the incidence of PML decreased from 14.8 cases/1,000 patients/year in 1996 to 2.6 in 2005 and 0.8 in 2011, and nearly two-thirds of recent cases (64 %) were observed in HIV patients not attending clinical visits. The baseline median CD4+ count was higher in recently PML-diagnosed patients (77 vs. 86 vs. 101 cells/mm(3); p < 0.01), and this fact was associated with a cerebrospinal fluid (CSF) inflammatory profile (from 11 to 31 to 55 %, p = 0.007) and with a significantly longer survival (attributable death, 54 vs. 35 vs. 36 %, respectively, p < 0.01). Thus, the overall 1-year and 3-year survival rates were 55 and 50 %, respectively, increasing to 79 % at 1 year for patients with CD4+ count above 100 cells/mm(3) at diagnosis. In a Cox regression analysis, an older age (hazard ratio, HR 0.76), a baseline CD4+ count above 100 cells/mm(3) (HR 0.33), and a CSF inflammatory profile (HR 0.12) were significantly associated with a longer survival. The clinical presentation and outcome of PML in AIDS patients continue to change dramatically. Now, a declining incidence and long-term survival is observed.

Progressive multifocal leukoencephalopathy (PML) associated with HIV Clade C--is not uncommon

Progressive multifocal leukoencephalopathy (PML) is a rare, subacute, demyelinating disease of the central nervous system caused by JC virus. Studies of PML from HIV Clade C prevalent countries are scarce. We sought to study the clinical, neuroimaging, and pathological features of PML in HIV Clade C patients from India. This is a prospective cum retrospective study, conducted in a tertiary care Neurological referral center in India from Jan 2001 to May 2012. Diagnosis was considered "definite" (confirmed by histopathology or JCV PCR in CSF) or "probable" (confirmed by MRI brain). Fifty-five patients of PML were diagnosed between January 2001 and May 2012. Complete data was available in 38 patients [mean age 39 ± 8.9 years; duration of illness-82.1 ± 74.7 days). PML was prevalent in 2.8 % of the HIV cohort seen in our Institute. Hemiparesis was the commonest symptom (44.7 %), followed by ataxia (36.8 %). Definitive diagnosis was possible in 20 cases. Eighteen remained "probable" wherein MRI revealed multifocal, symmetric lesions, hypointense on T1, and hyperintense on T2/FLAIR. Stereotactic biopsy (n = 11) revealed demyelination, enlarged oligodendrocytes with intranuclear inclusions and astrocytosis. Immunohistochemistry revelaed the presence of JC viral antigen within oligodendroglial nuclei and astrocytic cytoplasm. No differences in clinical, radiological, or pathological features were evident from PML associated with HIV Clade B. Clinical suspicion of PML was entertained in only half of the patients. Hence, a high index of suspicion is essential for diagnosis. There are no significant differences between clinical, radiological, and pathological picture of PML between Indian and Western countries.

Human polyomavirus reactivation: disease pathogenesis and treatment approaches

JC and BK polyomaviruses were discovered over 40 years ago and have become increasingly prevalent causes of morbidity and mortality in a variety of distinct, immunocompromised patient cohorts. The recent discoveries of eight new members of the Polyomaviridae family that are capable of infecting humans suggest that there are more to be discovered and raise the possibility that they may play a more significant role in human disease than previously understood. In spite of this, there remains a dearth of specific therapeutic options for human polyomavirus infections and an incomplete understanding of the relationship between the virus and the host immune system. This review summarises the human polyomaviruses with particular emphasis on pathogenesis in those directly implicated in disease aetiology and the therapeutic options available for treatment in the immunocompromised host.

Update on progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a severe, often fatal, opportunistic viral infection of the central nervous system that is mainly seen in the context of AIDS and certain monoclonal immune-suppressive therapies. The causative agent, a polyoma virus, named JC virus infects only humans and there is no animal model for PML. This update focuses on information gathered in recent years on the pathogenesis of the disorder, on several clinical aspects associated with diagnosis and therapy, and on the immune reconstitution inflammatory syndrome (IRIS), a complication associated with removal of immunosuppressive therapy in PML.

Favourable outcome of progressive multifocal leukoencephalopathy with mefloquine treatment in combination with antiretroviral therapy in an HIV-infected patient

A 33-year-old man who developed progressive multifocal leukoencephalopathy (PML) with HIV infection is reported. The patient exhibited rapid decline in neurological status after initiation of antiretroviral therapy (ART), which was attributed to the PML-immune re-constitution inflammatory syndrome. Following the administration of mefloquine in combination with ART, the patient's neurological status improved substantially. This case suggests that further investigation of the use of mefloquine might be warranted for treatment of PML in HIV-infected patients.

JC virus load in cerebrospinal fluid and transcriptional control region rearrangements may predict the clinical course of progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a severe disease of the central nervous system (CNS), caused by infection with the Polyomavirus JC virus (JCV). Because there are no known treatments or prognostic factors, we performed a long-term study focusing mainly on cerebrospinal fluid (CSF) samples from PML patients to describe the virological features akin to the different forms of the disease. Twenty-eight PML patients were enrolled: 10 HIV-1+ patients with classical PML (CPML), 9 HIV-1+ patients with slowly progressing or stable neurological symptoms (benign PML), 3 HIV-1+ asymptomatic patients, and 6 HIV-1-negative patients. CSF, urine, and blood samples were collected at the enrollment (baseline) and every 6 months afterwards when possible. The JCV DNA and HIV-1 RNA loads were determined, and the JCV strains were characterized. At baseline, the mean CSF JCV load was log 6.0 ± 1.2 copies/ml for CPML patients, log 4.0 ± 1.0 copies/ml for benign PML patients, log 4.2 ± 0.5 copies/ml for asymptomatic PML patients, and log 5.8 ± 1.3 copies/ml for HIV-1-negative PML patients (CPML vs. benign: P < 0.01; CPML vs. asymptomatic: P < 0.05; HIV-1 negative vs. benign: P < 0.01). Organization of the JCV transcriptional control region (TCR) showed unusual archetype structures in two long-term survival patients; the NF1 sequence was found most commonly, whereas the Sp1 binding site was the most common for both CPML patients and HIV-1 negative patients. Our results suggest that the JCV load in the CSF and the organization of the TCR should be considered as indicators of PML clinical outcome.

CNS-immune reconstitution inflammatory syndrome in the setting of HIV infection, part 1: overview and discussion of progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome and cryptococcal-immune reconstitution inflammatory syndrome

SUMMARY

While uncommon, CNS-IRIS developing after the initiation of HAART in the setting of HIV-related severe immunosuppression is characterized by an intense inflammatory reaction to dead or latent organisms or to self-antigens due to a heightened but dysregulated immune response. While this reaction can range from mild to fulminating, encompassing a very wide clinical spectrum, it is important to recognize because changes in medical management may be necessary to prevent neurologic decline and even death. Once contained, however, this inflammatory response can be associated with improved patient outcome as immune function is restored. Among the infectious organisms that are most commonly associated with CNS-IRIS are the JC virus and Cryptococcus organisms, which will be the subject of this review. CD8 cell infiltration in the leptomeninges, perivascular spaces, blood vessels, and even parenchyma seems to be the pathologic hallmark of CNS-IRIS. While recognition of CNS-IRIS may be difficult, the onset of new or progressive clinical symptoms, despite medical therapy and despite improved laboratory data, and the appearance on neuroimaging studies of contrast enhancement, interstitial edema, mass effect, and restricted diffusion in infections not typically characterized by these findings in the untreated HIV-infected patient should raise the strong suspicion for CNS-IRIS. While CNS-IRIS is a diagnosis of exclusion, the neuroradiologist can play a critical role in alerting the clinician to the possibility of this syndrome.

[Immune reconstitution syndrome]

The immune reconstitution inflammatory syndrome (IRIS) represents a heterogeneous group of conditions. Whilst they typically present in HIV-infected patients with advanced immunodeficiency, IRIS have also been described in HIV-negative patients with immune reconstitution due to other causes of immunosuppression. Frequently IRIS results from an immune response against underlying infection (pathogen-associated IRIS). However, IRIS might become evident during immune reconstitution without an underlying pathogen such as a sarcoid-like illness or an autoimmune thyropathy. Here we report on the epidemiology and risk factors of IRIS along with diagnosis and management of this clinically important inflammatory syndrome.

Progressive multifocal leukoencephalopathy: clinical and molecular aspects

The fatal CNS demyelinating disease, progressive multifocal leukoencephalopathy (PML), is rare and appears to occur almost always as a consequence of immune dysfunction. Thus, it is associated with HIV/AIDS and also as a side effect of certain immunomodulatory monoclonal antibody therapies. In contrast to the rarity of PML, the etiological agent of the disease, the polyomavirus JC (JCV), is widespread in populations worldwide. In the 40 years since JCV was first isolated, much has been learned about the virus and the disease from laboratory and clinical observations. However, there are many aspects of the viral life cycle and of the pathogenesis of the disease that remain unclear, and our understanding is constantly evolving. In this review, we will discuss our current understanding of the clinical features of PML and molecular characteristics of JCV and of how they relate to each other. Clinical observations can inform molecular studies of the virus, and likewise, molecular findings concerning the life cycle of the virus can guide the development of novel therapeutic strategies.

Clinical outcome of long-term survivors of progressive multifocal leukoencephalopathy

Progressive Multifocal Leukoencephalopathy (PML) is a demyelinating disease of the brain caused by the polyomavirus JC (JCV) in immunosuppressed people. There is no cure for PML but 1-year survival has increased from 10% to 50% in HIV-infected individuals treated with highly active antiretroviral therapy. We describe herein the clinical outcome of 24 PML patients whose survival exceeded 5 years, with a mean follow-up of 94.2 months (range, 60-188 months). Of all patients, only two were females including one who had non-Hodgkin's lymphoma and was HIV negative. All 23 HIV-positive patients received highly active antiretroviral therapy, and additional experimental therapies were not associated with a better clinical outcome. Marked neurological improvement occurred in 4/24 (17%) of patients, while 11/24 (46%) had partial improvement and 9/24 (37%) remained stable. By the end of the period of observation, 8/24 (33%) of patients had no significant disability despite persistent symptoms (modified Rankin disability scale (MRDS) =1), 6/24 (25%) had slight disability and were living independently (MRDS=2), 5/24 (21%) were moderately disabled, requiring some help during activities of daily living (MRDS=3) and 5/24 (21%) had moderately severe disability, requiring constant help or institutionalisation (MRDS=4). Patients with cerebellar lesions tended to have a worse clinical outcome. MRI showed leukomalacia with ventricular enlargement secondary to destruction of the white matter at the site of previous PML lesions, and focal areas of subcortical atrophy with preservation of the cortical ribbon. Of 20 patients tested, 19(95%) had detectable CD8+ cytotoxic T-lymphocytes against JCV in their blood. In absence of a specific treatment, immunotherapies aiming at boosting the cellular immune response against JCV may improve the prognosis of PML.

Monoclonal antibodies and progressive multifocal leukoencephalopathy

Since their introduction, monoclonal antibodies have found an ever expanding role in the treatment of a wide number of disorders. However, the perturbation of the immune system that attends their use may also increase the risk for the development of disorders that arise in the setting of immunosuppressive conditions, such as, opportunistic infection and malignancy. In this paper, we address the association between some monoclonal antibodies and the development of a rare demyelinating disease of the brain, progressive multifocal leukoencephalopathy (PML). PML results from infection with a ubiquitous polyoma virus, JC virus, and typically occurs in the setting of impaired immunity, most commonly, AIDS. It was first recognized as a potential complication of monoclonal antibody therapy in patients with multiple sclerosis and Crohn disease being treated with natalizumab, an alpha 4 beta1 and alpha 4 beta 7 integrin inhibitor. Subsequently, efalizumab, a monoclonal antibody used in the treatment of psoriasis, was also demonstrated to be associated with PML. An increased risk has been suggested for rituximab, although most of the patients developing PML with that monoclonal antibody have been treated for B-cell disorders that predispose to the development of PML. Based on our current understanding of the biology of JC virus and the pathogenesis of PML, we propose an explanation for the increased risk for PML that is observed with natalizumab and certain other monoclonal antibodies.

Progressive multifocal leucoencephalopathy in an immunocompetent patient with favourable outcome. A case report

BACKGROUND

To report the clinical course of PML in an apparently immunocompetent patient treated with cidofovir.

CASE PRESENTATION

A 35-year-old immunocompetent man who developed progressive hemianopsia, aphasia, and limb weakness underwent repeated MRI scans of the brain, spinal fluid analyses, and brain biopsy. Before diagnosis was established based on brain biopsy, he was consecutively treated with methylprednisolone, acyclovir, ceftriaxone and plasmapheresis, but he deteriorated rapidly suggestive of the immune reconstitution inflammatory syndrome (IRIS). He started to recover two weeks after the initiation of treatment with cidofovir and has had no relapse at 3 1/2 years of follow-up. MRI has shown marked improvement.

CONCLUSIONS

PML should be considered in immunocompetent patients with a typical clinical course and MRI findings compatible with PML. Treatment with cidofovir should be considered as early as possible in the disease course.

Immune reconstitution inflammatory syndrome in patients starting antiretroviral therapy for HIV infection: a systematic review and meta-analysis

In patients with HIV-1 infection who are starting combination antiretroviral therapy (ART), the incidence of immune reconstitution inflammatory syndrome (IRIS) is not well defined. We did a meta-analysis to establish the incidence and lethality of the syndrome in patients with a range of previously diagnosed opportunistic infections, and examined the relation between occurrence and the degree of immunodeficiency. Systematic review identified 54 cohort studies of 13 103 patients starting ART, of whom 1699 developed IRIS. We calculated pooled cumulative incidences with 95% credibility intervals (CrI) by Bayesian methods and did a random-effects metaregression to analyse the relation between CD4 cell count and incidence of IRIS. In patients with previously diagnosed AIDS-defining illnesses, IRIS developed in 37.7% (95% CrI 26.6-49.4) of those with cytomegalovirus retinitis, 19.5% (6.7-44.8) of those with cryptococcal meningitis, 15.7% (9.7-24.5) of those with tuberculosis, 16.7% (2.3-50.7) of those with progressive multifocal leukoencephalopathy, and 6.4% (1.2-24.7) of those with Kaposi's sarcoma, and 12.2% (6.8-19.6) of those with herpes zoster. 16.1% (11.1-22.9) of unselected patients starting ART developed any type of IRIS. 4.5% (2.1-8.6) of patients with any type of IRIS died, 3.2% (0.7-9.2) of those with tuberculosis-associated IRIS died, and 20.8% (5.0-52.7) of those with cryptococcal meningitis died. Metaregression analyses showed that the risk of IRIS is associated with CD4 cell count at the start of ART, with a high risk in patients with fewer than 50 cells per microL. Occurrence of IRIS might therefore be reduced by initiation of ART before immunodeficiency becomes advanced.

Unmasking of PML by HAART: unusual clinical features and the role of IRIS

For patients with HIV/AIDS, highly active antiretroviral therapy (HAART) is currently the only effective therapy for progressive multifocal leukoencephalopathy (PML), a viral-induced demyelinating disease caused by polyomavirus JC. Immune reconstitution inflammatory syndrome (IRIS) following initiation of HAART can cause paradoxical clinical deterioration in patients with established PML. Because the onset of PML follows soon after initiation of HAART in some cases (unmasking), we investigated the role IRIS plays in unmasked PML. We reviewed records of 20 PML cases seen from 1997-2006 at the UCSD HIV primary care clinic. Eight cases presented with PML symptoms within 6months of initiating HAART (referred to hereafter as unmasked PML), six patients were diagnosed with PML before initiating HAART, and six were diagnosed more than 6months after starting HAART. Patients with unmasked PML constituted 40% of our series, had relatively long survival, and commonly (50%) had lesions exclusively in the posterior fossa, a localization not previously reported with such a high prevalence. Only 3 of the 8 patients with unmasked PML had IRIS reactions as evidenced by contrast enhancement around lesions on MRI, suggesting that IRIS is not necessary for the pathogenesis of this syndrome.

Determinants of survival in progressive multifocal leukoencephalopathy

BACKGROUND

We sought to characterize the role of immunologic, virologic, and radiologic determinants of survival in patients with progressive multifocal leukoencephalopathy (PML).

METHODS

We recorded the clinical outcome of 60 patients with PML (73% HIV+) who were prospectively evaluated between 2000 and 2007 for the presence of JC virus (JCV)-specific CD8+ cytotoxic T-lymphocytes (CTL) in blood.

RESULTS

Estimated probability of survival at 1 year was 52% for HIV+/PML and 58% for HIV- patients with PML. Patients with PML with detectable CTL within 3 months of diagnosis had a 1-year estimated survival of 73% compared to 46% for those without CTL (hazard ratio [HR] for death = 0.47, 95% confidence interval [CI] 0.13-1.75, p = 0.26). Patients with CTL response had an increased likelihood of having contrast enhancement of PML lesions and immune reconstitution inflammatory syndrome (odds ratio 3.7 and 7.8). Estimated 1-year survival was 48% in HIV+ patients with PML with CD4 count <200/microL at PML diagnosis compared to 67% in those with CD4 >200/microL (HR for death 1.41, 95% CI 0.27-7.38, p = 0.68). JCV DNA was detected in the urine of 48% and in the blood of 56% of patients with PML, but viruria and viremia were not associated with survival.

CONCLUSIONS

The presence of JC virus (JCV)-specific cytotoxic T-lymphocytes (CTL) was associated with a trend toward longer survival in patients with progressive multifocal leukoencephalopathy (PML), which was more pronounced than the impact of CD4 count in HIV+ patients with PML early after diagnosis. Despite the association of contrast enhancement and immune reconstitution inflammatory syndrome with JCV-specific CTL, these cannot be considered as surrogate markers for the prognostic value of the CTL. Strategies aiming at improving the cellular immune response may improve the course of PML.

Clinical vigilance for progressive multifocal leukoencephalopathy in the context of natalizumab use

Natalizumab therapy for patients with multiple sclerosis (MS) has been associated with both improved clinical outcomes and an increased incidence of progressive multifocal leukoencephalopathy (PML). We provide details of the etiology and recent history of PML as associated with immunosuppressive disease states, including MS. Furthermore, it offers clinical guidance on differentiating PML from a MS relapse and a review of the current treatment options for patients suspected of having developed the complication.

Progressive multifocal leukoencephalopathy in HIV-1 infection

Progressive multifocal leukoencephalopathy is caused by the JC polyomavirus (JCV) and is one of the most feared complications of HIV-1 infection. Unlike other opportunistic infections, this disease can present when CD4 counts are higher than those associated with AIDS and when patients are receiving combined antiretroviral therapy, either shortly after starting or, more rarely, during long term successful treatment. Clinical suspicion of the disease is typically when MRI shows focal neurological deficits and associated demyelinating lesions; however, the identification of JCV in cerebrospinal fluid or brain tissue is needed for a definitive diagnosis. Although no specific treatment exists, the reversal of immunosuppression by combined antiretroviral therapy leads to clinical and MRI stabilisation in 50-60% of patients with the disease, and JCV clearance from cerebrospinal fluid. A substantial proportion of patients treated with combined antiretroviral therapy develop inflammatory lesions, which can be associated with either a favourable outcome or clinical worsening. The reasons for variability in the natural history of progressive multifocal leukoencephalopathy and treatment responses are largely undefined, and more specific and rational approaches to management are needed.

Progressive Multifocal Leukoencephalopathy in HIV-Infected Children: A Case Report and Literature Review

We report a case of a perinatally HIV-infected patient aged 9 years, who presented with right-sided hemiplegia. His initial CD4 T-cell was of 0.21% (4 cells/μL) and plasma HIV RNA virus of 185 976 copies/mL (log 5.27). Plasma and CSF samples were subsequently positive for JCV. Twelve days after the initiation of highly active antiretroviral therapy (HAART), the MRI showed progressive white matter lesions with asymmetrical deep and subcortical white matter lesions over the left frontotemporoparietal region and the right frontal lobe. Immune Reconstitution Inflammatory Syndrome (IRIS) was suspected, and the patient was treated with methylprednisolone. His clinical symptoms worsened and despite therapy the patient deteriorated.

Progressive multifocal leukoencephalopathy, a review and an extended report of five patients with different immune compromised states

Progressive multifocal leukoencephalopathy (PML) is an opportunistic infection of the brain caused by the JC-virus. Both a decreased cellular or humoral immune response can increase the susceptibility for JC-virus induced PML. Not only HIV infected people are at risk, a wide range of otherwise immune compromised patients are a potential target for this virus. This report of five PML patients shows the importance of a clinician's familiarity with this disease and it's presenting symptoms. The presenting symptoms of PML can sometimes mimic worsening of the underlying disease. Although different therapeutic strategies have been tried, the outcomes remain very poor. In this series, treatment with cidofovir appears not to be effective in treating PML, neither in HIV positive nor HIV negative patients. Experimental therapy with leflunomide, after tapering of the immunosuppressive medication, did change the natural course of PML in one patient.

Incidence, clinical presentation, and outcome of progressive multifocal leukoencephalopathy in HIV-infected patients during the highly active antiretroviral therapy era: a nationwide cohort study

BACKGROUND

Human immunodeficiency virus (HIV) infection predisposes to progressive multifocal leukoencephalopathy (PML). Here, we describe the incidence, presentation, and prognosis of PML in HIV-1-infected patients during the period before highly active antiretroviral therapy (HAART) (1995-1996) and during the early HAART (1997-1999) and late HAART (2000-2006) periods.

METHODS

Patients from a nationwide population-based cohort of adult HIV-1-infected individuals were included. We calculated incidence rates of PML and median survival times after diagnosis. We also described neurological symptoms at presentation and follow-up.

RESULTS

Among 4,649 patients, we identified 47 patients with PML. The incidence rates were 3.3, 1.8, and 1.3 cases per 1000 person-years at risk in 1995-1996, 1997-1999, and 2000-2006, respectively. The risk of PML was significantly associated with low CD4(+) cell count, and 47% of cases were diagnosed by means of brain biopsy or polymerase chain reaction analysis for JC virus. The predominant neurological symptoms at presentation were coordination disturbance, cognitive defects, and limb paresis. Thirty-five patients died; the median survival time was 0.4 years (95% confidence interval [CI], 0.0-0.7) in 1995-1996 and 1.8 years (95% CI, 0.6-3.0) in both 1997-1999 and 2000-2006. CD4(+) cell count >50 cells/microL at diagnosis of PML was significantly associated with reduced mortality.

CONCLUSIONS

The incidence of PML in HIV-infected patients decreased after the introduction of HAART. Survival after PML remains poor. In the management of PML, the main focus should be on prophylactic measures to avoid immunodeficiency.

JC virus-specific immune responses in human immunodeficiency virus type 1 patients with progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a frequently fatal disease caused by uncontrolled polyomavirus JC (JCV) in severely immunodeficient patients. We investigated the JCV-specific cellular and humoral immunity in the Swiss HIV Cohort Study. We identified PML cases (n = 29), as well as three matched controls per case (n = 87), with prospectively cryopreserved peripheral blood mononuclear cells and plasma at diagnosis. Nested controls were matched according to age, gender, CD4(+) T-cell count, and decline. Survivors (n = 18) were defined as being alive for >1 year after diagnosis. Using gamma interferon enzyme-linked immunospot assays, we found that JCV-specific T-cell responses were lower in nonsurvivors than in their matched controls (P = 0.08), which was highly significant for laboratory- and histologically confirmed PML cases (P = 0.004). No difference was found between PML survivors and controls or for cytomegalovirus-specific T-cell responses. PML survivors showed significant increases in JCV-specific T cells (P = 0.04) and immunoglobulin G (IgG) responses (P = 0.005). IgG responses in survivors were positively correlated with CD4(+) T-cell counts (P = 0.049) and negatively with human immunodeficiency virus RNA loads (P = 0.03). We conclude that PML nonsurvivors had selectively impaired JCV-specific T-cell responses compared to CD4(+) T-cell-matched controls and failed to mount JCV-specific antibody responses. JCV-specific T-cell and IgG responses may serve as prognostic markers for patients at risk.