PML diagnostic criteria: consensus statement from the AAN Neuroinfectious Disease Section

Presentation and Outcome in S1P-RM and Natalizumab-Associated Progressive Multifocal Leukoencephalopathy: A Multicenter Cohort Study

BACKGROUND AND OBJECTIVES

Progressive multifocal leukoencephalopathy (PML) is a severe neurologic disease resulting from JC virus reactivation in immunocompromised patients. Certain multiple sclerosis (MS) disease-modifying therapies (DMTs) are associated with PML risk, such as natalizumab and, more rarely, sphingosine-1-phosphate receptor modulators (S1P-RMs). Although natalizumab-associated PML is well documented, information on S1P-RM-associated PML is limited. The aim of this study is to compare clinical presentations and outcomes between the 2 groups.

METHODS

A retrospective multicenter cohort study included patients with PML from 2009 to 2022 treated with S1P-RMs or natalizumab. Data on clinical and radiologic presentation, outcomes, immune reconstitution inflammatory syndrome (IRIS), survival, disability (using the modified Ranking scale-mRS), and MS relapses post-PML were analyzed.

RESULTS

Of 88 patients, 84 were analyzed (20 S1P-RM, 64 natalizumab). S1P-RM-associated PML was diagnosed in older patients (median age 52 vs 44 years, p < 0.001) and after longer treatment duration (median 63.9 vs 40 months, p < 0.001). Similarly, S1P-RM patients were more prone to show symptoms at diagnosis (100 vs 80.6%, p = 0.035), had more disseminated lesions (80% vs 34.9%, p = 0.002), and had higher gadolinium enhancement (65% vs 39.1%, p = 0.042). Natalizumab patients had a higher IRIS development rate (OR: 8.3 [1.92-33.3]). Overall, the outcome (mRS) at 12 months was similar in the 2 groups (OR: 0.81 [0.32-2.0]). Yet, post-treatment MS activity was higher in S1P-RM cases (OR: 5.7 [1.4-22.2]).

DISCUSSION

S1P-RM-associated PML shows reduced IRIS risk but higher post-treatment MS activity. Clinicians should tailor post-PML treatment based on pre-PML medication.

Progressive multifocal leukoencephalopathy in sarcoidosis successfully treated with pembrolizumab

Progressive multifocal leukoencephalopathy (PML) is a severe, demyelinating disease of the central nervous system caused by JC virus infection. The disease can be seen in sarcoidosis patients without additional risk factors. Here, we present an individual with PML secondary to sarcoidosis treated with 8 doses of pembrolizumab, a Programmed Cell-Death-1 (PD-1) Immune Checkpoint Inhibitor who showed significant improvement. This report illustrates the objective clinical and radiological improvement in a patient with PML due to sarcoidosis, and suggests further study of immune checkpoint inhibitors as a potential treatment for sarcoidosis patients with PML.

Treatment Monitoring in Multiple Sclerosis - Efficacy and Safety

Magnetic resonance imaging is the most sensitive method for detecting inflammatory activity in multiple sclerosis, particularly in the brain where it reveals subclinical inflammation. Established MRI markers include contrast-enhancing lesions and active T2 lesions. Recent promising markers like slowly expanding lesions and phase rim lesions are being explored for monitoring chronic inflammation, but require further validation for clinical use. Volumetric and quantitative MRI techniques are currently limited to clinical trials and are not yet recommended for routine clinical use. Additionally, MRI is crucial for detecting complications from disease-modifying treatments and for implementing MRI-based pharmacovigilance strategies, such as in patients treated with natalizumab.

Progressive multifocal leukoencephalopathy and spectrum of predisposing conditions: a 20-year retrospective cohort study in a tertiary center in São Paulo, Brazil

BACKGROUND

Epidemiological studies on predisposing conditions and outcomes of progressive multifocal leukoencephalopathy (PML) cases have been carried out exclusively in high-income countries. We aim to report and compare the main characteristics and outcomes of patients with PML and several underlying diseases in a referral center in a middle-income country.

METHODS

We performed a retrospective cohort study of PML cases admitted to a tertiary care hospital in São Paulo, Brazil during 2000-2022. Demographic and PML-specific variables were recorded. One-year case-fatality rate and factors associated with death were identified using a multivariate Cox proportional hazards regression model.

RESULTS

Ninety-nine patients with PML were included. HIV infection (84.8%) and malignancy (14.1%) were the most prevalent underlying conditions. Other predisposing diseases were autoimmune/inflammatory diseases (5.1%) and solid organ transplantation (1.0%). One (1.0%) patient had liver cirrhosis and another (1.0%) patient was previously healthy. Focal motor deficits (64.2%) and gait instability (55.1%) were the most common signs. The one-year case-fatality rate was 52.5% (95% CI 42.2-62.7). The one-year case-fatality rate (95% CI) in patients with or without malignancy (85.7%, 95% CI 57.2-98.2% and 47.1%, 95% CI 36.1-58.2%, respectively) were statistically different (P = 0.009). Crude and adjusted Cox regression models identified malignancy as independently associated with death (adjusted HR = 3.92, 95% CI 1.76-8.73, P = 0.001).

CONCLUSIONS

HIV/AIDS was the predisposing condition in 84.8% of PML cases. The one-year case-fatality rate was 52.5% and having a malignancy was independently associated with death. This study reports emerging data on the epidemiology and outcome of PML in a middle-income country.

Highly restrictive and directional penetration of the blood cerebral spinal fluid barrier by JCPyV

The human polyomavirus JCPyV is an opportunistic pathogen that infects greater than 60% of the world's population. The virus establishes a persistent and asymptomatic infection in the urogenital system but can cause a fatal demyelinating disease in immunosuppressed or immunomodulated patients following invasion of the CNS. The mechanisms responsible for JCPyV invasion into CNS tissues are not known but direct invasion from the blood to the cerebral spinal fluid via the choroid plexus has been hypothesized. To study the potential of the choroid plexus as a site of neuroinvasion, we used an adult human choroid plexus epithelial cell line to model the blood-cerebrospinal fluid (B-CSF) barrier in a transwell system. We found that these cells formed a highly restrictive barrier to virus penetration either as free virus or as virus associated with extracellular vesicles (EVJC+). The restriction was not absolute and small amounts of virus or EVJC+ penetrated and were able to establish foci of infection in primary astrocytes. Disruption of the barrier with capsaicin did not increase virus or EVJC+ penetration leading us to hypothesize that virus and EVJC+ were highly cell-associated and crossed the barrier by an active process. An inhibitor of macropinocytosis increased virus penetration from the basolateral (blood side) to the apical side (CSF side). In contrast, inhibitors of clathrin and raft dependent transcytosis reduced virus transport from the basolateral to the apical side of the barrier. None of the drugs inhibited apical to basolateral transport suggesting directionality. Pretreatment with cyclosporin A, an inhibitor of P-gp, MRP2 and BCRP multidrug resistance transporters, restored viral penetration in cells treated with raft and clathrin dependent transcytosis inhibitors. Because choroid plexus epithelial cells are known to be susceptible to JCPyV infection both in vitro and in vivo we also examined the release of infectious virus from the barrier. We found that virus was preferentially released from the cells into the apical (CSF) chamber. These data show clearly that there are two mechanisms of penetration, direct transcytosis which is capable of seeding the CSF with small amounts of virus, and infection followed by directional release of infectious virions into the CSF compartment.

A case of a cerebellar form of progressive multifocal leukoencephalopathy in a patient undergoing peritoneal dialysis

Progressive multifocal leukoencephalopathy (PML), a severe demyelinating disease of the central nervous system, is caused by the reactivation of the polyomavirus JC virus (JCV). It favors the cerebrum and typically occurs in patients with immunodeficiencies, with a progressive course and fatal outcome in the majority of cases. However, the cerebellar form of PML, characterized by isolated posterior fossa lesions, such as those in the cerebellum or brainstem at disease onset, is rare, and reports of its occurrence in peritoneal dialysis (PD) patients are lacking. In this paper, we describe a rare case of a cerebellar form of PML in a PD patient. A 64-year-old man undergoing PD was referred to our hospital for anorexia, nausea, and vomiting in the past month. He had finger-to-nose test abnormalities, gaze-directed nystagmus, and scanning speech. He was diagnosed with the cerebellar form of PML based on his progressive cerebellar symptoms, the typical magnetic resonance imaging findings, and the presence of JCV-DNA in the cerebrospinal fluid polymerase chain reaction test. He developed nocturnal delirium, aggravated disquiet, and died of pneumonia on the 69th day. Clinicians should consider the cerebellar form of PML as a differential diagnosis if PD patients develop progressive cerebellar symptoms.

Atypical Presentation of a Patient With Progressive Multifocal Leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a rare, demyelinating infectious disease of the central nervous system, primarily affecting immunosuppressed individuals, such as those with acquired immunodeficiency syndrome (AIDS) or undergoing immunosuppressive therapy. The causative agent is the dormant John Cunningham (JC) polyomavirus, which reactivates in immunocompromised patients. PML is diagnosed through clinical observations, imaging, and polymerase chain reaction (PCR) analysis, detecting JC virus deoxyribonucleic acid (DNA) in the cerebrospinal fluid (CSF). Here, we report a case of a 42-year-old male, recently diagnosed with human immunodeficiency virus (HIV), who presented with slurred speech, difficulty articulating, tingling in both feet, difficulty walking, and significant weight loss. Examination revealed absent reflexes, coordination impairment, and diminished vibration sense. Blood tests showed anemia, elevated D-dimer, and HIV-1 positivity with a low CD4 count. CSF analysis indicated a lymphocytic profile with elevated protein and marginally increased adenosine deaminase (ADA). Autoantibody testing was positive for antinuclear antibodies (ANA), but CSF culture and India ink staining were negative. Magnetic resonance imaging (MRI) of the brain revealed hyperintense lesions on T2-weighted and fluid-attenuated inversion recovery (FLAIR) images in the left peritrigonal and parietal white matter, suggesting demyelination. The diagnosis of PML was confirmed by a positive JC virus PCR result from the CSF. The patient was started on combination antiretroviral therapy (cART) and supportive measures to improve immune status. This case underscores the importance of considering PML in patients with new-onset neurological symptoms and immunosuppression.

Spinal cord involvement in progressive multifocal leukoencephalopathy and immune reconstitution inflammatory syndrome

Progressive multifocal leukoencephalopathy (PML) is an opportunistic infectious demyelinating disease of the central nervous system caused by JC polyomavirus predominantly affecting immunocompromised individuals. Nowadays, HIV, hematological malignancies and iatrogenic immune suppression account for most PML cases. For unknown reasons, spinal cord is classically protected from PML lesions. Here, we report the course of a patient harboring spinal cord lesions in the context of PML with immune reconstitution inflammatory syndrome and review the eight other cases reported in the literature so far. Then, we discuss the evolving spectrum of PML over recent years, potentially making its diagnosis more challenging.

John Cunningham Virus and Progressive Multifocal Leukoencephalopathy: A Falsely Played Diagnosis

Progressive Multifocal Leukoencephalopathy (PML) is a possibly fatal demyelinating disease and John Cunningham Polyomavirus (JCPyV) is believed to cause this condition. The so-called JCPyV was initially reported in lymphoma and Human Immunodeficiency Virus (HIV) cases, whereas nowadays, its incidence is increasing in Multiple Sclerosis (MS) cases treated with natalizumab (Tysabri). However, there are conflicting literature data on its pathology and diagnosis, whereas some misdiagnosed reports exist, giving rise to further questions towards the topic. In reality, the so-called PML and the supposed JCPyV are not what they seem to be. In addition, novel and more frequent PML-like conditions may be reported, especially after the Coronavirus Disease 2019 (COVID-19) pandemic.

Progressive Multifocal Leukoencephalopathy Unmasked by Teclistamab in a Refractory Multiple Myeloma Patient

This case report describes the development of Progressive Multifocal Leukoencephalopathy (PML) in a 72-year-old male with relapsed/refractory multiple myeloma (RRMM), following a single dose of teclistamab amidst a COVID-19 infection. Shortly after starting teclistamab treatment, the patient developed symptoms, including fever, altered mental status, and right-sided paresis. A diagnosis of PML was confirmed through the detection of JC virus PCR in the cerebrospinal fluid. Our report emphasizes the occurrence of PML after only one dose of teclistamab and highlights teclistamab's potential for severe infectious complications, despite its promise in treating RRMM.

Biomarkers for progressive multifocal leukoencephalopathy: emerging data for use of JC virus DNA copy number in clinical trials

Progressive multifocal leukoencephalopathy is a rare but devastating demyelinating disease caused by the JC virus (JCV), for which no therapeutics are approved. To make progress towards addressing this unmet medical need, innovations in clinical trial design are needed. Quantitative JCV DNA in CSF has the potential to serve as a valuable biomarker of progressive multifocal leukoencephalopathy disease and treatment response in clinical trials to expedite therapeutic development, as do neuroimaging and other fluid biomarkers such as neurofilament light chain. Specifically, JCV DNA in CSF could be used in clinical trials as an entry criterion, stratification factor, or predictor of clinical outcomes. Insights from the investigation of candidate biomarkers for progressive multifocal leukoencephalopathy might inform approaches to biomarker development for other rare diseases.

Progressive multifocal leukoencephalopathy in patients with chronic kidney disease

Progressive multifocal leukoencephalopathy (PML) is an opportunistic central nervous system infection caused by the human polyomavirus 2, leading to demyelination from oligodendrocyte death and rapid neurologic decline. Most commonly, PML affects patients in immunocompromised states. However, rare reports of PML in an immunocompetent host exist. Here, we report two cases of PML in older individuals with chronic kidney disease (CKD). CKD can ultimately lead to immune system dysfunction and place patients in a relatively immunosuppressed state. Testing for JC virus should remain a consideration for rapid, unexplained neurologic decline even without known immunocompromised status in the appropriate clinical setting.

Progressive multifocal leukoencephalopathy in a lung transplant recipient

Progressive multifocal leukoencephalopathy (PML) is a rare and fatal demyelinating disease of the central nervous system (CNS). The case we describe highlights the importance of considering a diagnosis of PML early (<1 year) after lung transplant.

The diagnosis of central nervous system infections in resource-limited settings and the use of novel and molecular diagnostic platforms to improve diagnosis

INTRODUCTION

Central nervous system infections (CNSI) disproportionately affect individuals in low-resource settings where diagnosis is challenging; large proportions of patients never receive a confirmed microbiological diagnosis resulting in inadequate management and high mortality. The epidemiology of CNSI varies globally and conventional diagnostics deployed in resource-limited settings have significant limitations, with an urgent need for improved diagnostic strategies.

AREAS COVERED

This review describes molecular platforms and other novel diagnostics used in the diagnosis of CNSI that are applicable to resource-limited settings. An extensive literature search of Medline and PubMed was performed. The emphasis is on investigations targeting infections of relevance to resource-limited settings either due to variation in regional CNSI epidemiology or due to increased prevalence in patients with immunosuppression. This includes commercially available multiplex PCR platforms, mycobacterial PCR platforms, and rapid diagnostics tests. To offer a framework for the optimal implementation in clinical settings, existing evidence highlighting the advantages and limitations of available platforms is reviewed.

EXPERT OPINION

The implementation of molecular platforms and other novel diagnostics has the potential to transform CNSI diagnosis in resource-limited settings, with several examples of successful rollout of novel diagnostics such as Xpert MTB/RIF Ultra and cryptococcal antigen testing.

Progressive multifocal leukoencephalopathy as the presenting feature in a patient with occult low-count monoclonal B-cell lymphocytosis

Introduction

Low Count Monoclonal B-Cell Lymphocytosis (LC-MBL) is a relatively poorly understood entity which has been suggested to be very common in asymptomatic adults and possibly related to infectious complications despite not progressing to CLL.

Methods

We describe the first case of Progressive Multifocal Leukoencephalopathy (PML) presenting in a 72-year-old man with LC-MBL but no other immunocompromising conditions.

Results

A diagnosis of PML was confirmed with classic MRI findings in association with a high CSF John Cunningham polyomavirus (JCV) viral load (4.09' 105 copies/mL). An extensive search for underlying immunocompromising conditions only demonstrated LC-MBL representing approximately 4% of total leukocytes (0.2' 109/L).

Discussion

This is the first report of PML in association with LC-MBL. Careful review of peripheral blood flow cytometry results is necessary to identify this disorder. Further study of the epidemiology and infectious complications of LC-MBL are warranted.

Viral meningoencephalitis in pediatric solid organ or hematopoietic cell transplant recipients: a diagnostic and therapeutic approach

Neurologic complications, both infectious and non-infectious, are frequent among hematopoietic cell transplant (HCT) and solid organ transplant (SOT) recipients. Up to 46% of HCT and 50% of SOT recipients experience a neurological complication, including cerebrovascular accidents, drug toxicities, as well as infections. Defects in innate, adaptive, and humoral immune function among transplant recipients predispose to opportunistic infections, including central nervous system (CNS) disease. CNS infections remain uncommon overall amongst HCT and SOT recipients, compromising approximately 1% of total cases among adult patients. Given the relatively lower number of pediatric transplant recipients, the incidence of CNS disease amongst in this population remains unknown. Although infections comprise a small percentage of the neurological complications that occur post-transplant, the associated morbidity and mortality in an immunosuppressed state makes it imperative to promptly evaluate and aggressively treat a pediatric transplant patient with suspicion for viral meningoencephalitis. This manuscript guides the reader through a broad infectious and non-infectious diagnostic differential in a transplant recipient presenting with altered mentation and fever and thereafter, elaborates on diagnostics and management of viral meningoencephalitis. Hypothetical SOT and HCT patient cases have also been constructed to illustrate the diagnostic and management process in select viral etiologies. Given the unique risk for various opportunistic viral infections resulting in CNS disease among transplant recipients, the manuscript will provide a contemporary review of the epidemiology, risk factors, diagnosis, and management of viral meningoencephalitis in these patients.

Eyelid Molluscum Contagiosum: A Sign of Advanced HIV Infection

HIV infection can present with dermatologic pathologies, and molluscum contagiosum in the eyelid is a specific sign often related to advanced HIV. Herein, we present the case of an adult patient with eyelid molluscum contagiosum that had been present for the last five years. Despite previous healthcare evaluation, the patient was not tested for HIV infection until presenting to our healthcare facility. The patient was diagnosed with AIDS. Our case highlights the importance of recognizing indirect signs of immunosuppression and the need to promptly order an HIV test. Additionally, we want to emphasize the importance of raising awareness about routine HIV testing, aiming to reduce the social stigma surrounding this test.

Cerebellar progressive multifocal leucoencephalopathy identified by the shrimp sign

Progressive multifocal leucoencephalopathy (PML) is a demyelinating disease caused by the John Cunningham (JC) virus, which may get reactivated under certain immunosuppressive states such as AIDS, immunomodulatory therapy and haematological malignancies. PML has been reported rarely even in immunocompetent individuals where no immunodeficiency was present. PML characteristically involves periventricular and juxtacortical white matter. Isolated cerebellar or brainstem PML may be seen rarely. We present a case of a man in his 70s who presented with rapidly progressive cerebellar ataxia, ptosis and bipyramidal signs. Investigations excluded a direct viral cerebellar infection, acute disseminated encephalomyelitis, paraneoplastic cerebellar degeneration or any structural cerebellar lesion. MRI PET study revealed the classical shrimp sign which raised the possibility of cerebellar PML, and the same was confirmed by a positive JC virus PCR in the cerebrospinal fluid. Our patient had no known immune-compromising state, but further workup revealed a low CD4 count suggestive of idiopathic CD4 lymphopenia. The case illustrates the importance of the shrimp sign on MRI, the possibility of cerebellar involvement of PML as well as the need to consider a differential diagnosis of PML even in individuals with no obvious immunocompromised state.

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.

Progressive multifocal leukoencephalopathy analyzed using the Japanese Adverse Drug Event Report database

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) has been reported as the development of drugs with immunomodulatory properties, such as anticancer, immunosuppressive, and biological agents, has accelerated. To clarify an incidence profile of drug-associated PML in real-world clinical practice, we analyzed reported patients with PML using the Japanese Adverse Drug Event Report (JADER) database.

METHODS

We analyzed PML reports extracted from the JADER database based on the preferred term of "progressive multifocal leukoencephalopathy" from between 2004 and 2021. This was a retrospective, observational study. We evaluated the effects of causative drugs, underlying diseases, and the age of the patients on the annual number of PML reports.

RESULTS

The JADER database contained 773,966 reports published between April 2004 and March 2022, from which we identified 361 PML events. These PML events may include multiple counts of the same case reported by different pathways and patients diagnosed with probable or possible PML. The number of PML reports and reporting ratios have gradually increased over the past decade. The annual number of PML reports associated with biologics, immunosuppressants, and antineoplastic drugs showed an increasing trend. Females aged ≥30 years showed an increase in PML reports; in contrast, there the number of reports for males aged ≥50 years increased.

CONCLUSIONS

The number of PML reports and reporting ratios have gradually increased in the past decade in Japan, and it considered that it was related to change in the treatment of malignancies and autoimmune diseases, and the increasing use of biologics, immunosuppressive agents, and antineoplastic agents.

Comprehensive proteomic analysis of JC polyomavirus-infected human astrocytes and their extracellular vesicles

IMPORTANCE

Progressive multifocal leukoencephalopathy is a crimpling demyelinating disease of the central nervous system caused by JC polyomavirus (JCPyV). Much about JCPyV propagation in the brain remains obscure because of a lack of proper animal models to study the virus in the context of the disease, thus hampering efforts toward the development of new antiviral strategies. Here, having established a robust and representative model of JCPyV infection in human-induced pluripotent stem cell-derived astrocytes, we are able to fully characterize the effect of JCPyV on the biology of the cells and show that the proteomic signature observed for JCPyV-infected astrocytes is extended to extracellular vesicles (EVs). These data suggest that astrocyte-derived EVs found in body fluids might serve as a rich source of information relevant to JCPyV infection in the brain, opening avenues toward better understanding the pathogenesis of the virus and, ultimately, the identification of new antiviral targets.

Progressive multifocal leukoencephalopathy triggered by COVID-19 in a previously asymptomatic person living with undiagnosed HIV infection

This report presents the case of a 47-year-old male patient who worked as a mathematics teacher and experienced the sudden onset of disorientation, aphasia, and acalculia during an online class. The current study reveals the first documented case of HIV and progressive multifocal leukoencephalopathy with the detection of SARS-CoV-2 and human polyomavirus 2 (previously known as John Cunningham virus) in the cerebrospinal fluid. Furthermore, serum analysis revealed elevated concentrations of interleukin (IL)-6, IL-17, and IL-8, which are potential factors known to reduce the expression of tight junctions and adhesion molecules in the extracellular matrix, thereby affecting the permeability of the blood-brain barrier. Finally, the study discusses whether SARS-CoV-2 triggers or exacerbates progressive multifocal leukoencephalopathy.

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.

Progressive Multifocal Leukoencephalopathy in Systemic Lupus Erythematosus: A Consequence of Patient-Intrinsic or -Extrinsic Factors?

Progressive multifocal leukoencephalopathy (PML) is a severe demyelinating disease of the central nervous system (CNS) caused by reactivation of the polyomavirus JC (JCV) typically in immunocompromised individuals. The risk of PML among rheumatic diseases may be higher for systemic lupus erythematosus (SLE), without, however, a clear association with the type and intensity of background therapy. We present the development and outcome of PML in a 32-year-old female lupus patient under mild immunosuppressive treatment, yet with marked B-cell lymphopenia in the peripheral blood and bone marrow (<1% of total lymphocytes). Despite treatment with the immune checkpoint inhibitor pembrolizumab, the patient showed progressive neurological and brain imaging deterioration and eventually died 15 months after PML diagnosis. To unveil possible underlying genetic liabilities, whole exome sequencing was performed which identified deleterious variants in GATA2 and CDH7 genes, which both have been linked to defective T- and/or B-lymphocyte production. These findings reiterate the possible role of disease-/patient-intrinsic factors, rather than that of drug-induced immunosuppression, in driving immune dysregulation and susceptibility to PML in certain patients with SLE.

Practical Clinical Guidelines for Natalizumab Treatment in Patients With Relapsing Multiple Sclerosis

Natalizumab (TYSABRI®) was the first high-efficacy monoclonal antibody disease-modifying therapy (DMT) approved as a monotherapy for the treatment of adults with relapsing forms of multiple sclerosis (MS), including clinically isolated syndrome, relapsing-remitting MS, and active secondary progressive MS. Because natalizumab is administered by intravenous infusion, infusion nurses play a key role in the care of natalizumab-treated patients. In the 16 years since approval, substantial data have been gathered on the long-term, real-world effectiveness and safety of natalizumab. This article provides a synopsis of this data, as well as practical information for optimizing patient care. This includes information on strategies to mitigate the risk of progressive multifocal leukoencephalopathy in natalizumab-treated patients, natalizumab use during pregnancy, and use with vaccines. It also includes guidance on the preparation and administration of natalizumab and monitoring of natalizumab-treated patients.

Polyomavirus Wakes Up and Chooses Neurovirulence

JC polyomavirus (JCPyV) is a human-specific polyomavirus that establishes a silent lifelong infection in multiple peripheral organs, predominantly those of the urinary tract, of immunocompetent individuals. In immunocompromised settings, however, JCPyV can infiltrate the central nervous system (CNS), where it causes several encephalopathies of high morbidity and mortality. JCPyV-induced progressive multifocal leukoencephalopathy (PML), a devastating demyelinating brain disease, was an AIDS-defining illness before antiretroviral therapy that has "reemerged" as a complication of immunomodulating and chemotherapeutic agents. No effective anti-polyomavirus therapeutics are currently available. How depressed immune status sets the stage for JCPyV resurgence in the urinary tract, how the virus evades pre-existing antiviral antibodies to become viremic, and where/how it enters the CNS are incompletely understood. Addressing these questions requires a tractable animal model of JCPyV CNS infection. Although no animal model can replicate all aspects of any human disease, mouse polyomavirus (MuPyV) in mice and JCPyV in humans share key features of peripheral and CNS infection and antiviral immunity. In this review, we discuss the evidence suggesting how JCPyV migrates from the periphery to the CNS, innate and adaptive immune responses to polyomavirus infection, and how the MuPyV-mouse model provides insights into the pathogenesis of JCPyV CNS disease.

Progressive Multifocal Leukoencephalopathy: Pathogenesis, Diagnostic Tools, and Potential Biomarkers of Response to Therapy

JC polyomavirus (JCV) establishes an asymptomatic latent and/or persistent infection in most of the adult population. However, in immunocompromised individuals, JCV can cause a symptomatic infection of the brain, foremost progressive multifocal leukoencephalopathy (PML). In the past 2 decades, there has been increasing concern among patients and the medical community because PML was observed as an adverse event in individuals treated with modern (selective) immune suppressive treatments for various immune-mediated diseases, especially multiple sclerosis. It became evident that this devastating complication also needs to be considered beyond the patient populations historically at risk, including those with hematologic malignancies or HIV-infected individuals. We review the clinical presentation of PML, its variants, pathogenesis, and current diagnostic approaches. We further discuss the need to validate JCV-directed interventions and highlight current management strategies based on early diagnosis and restoring JCV-specific cellular immunity, which is crucial for viral clearance and survival. Finally, we discuss the importance of biomarkers for diagnosis and response to therapy, instrumental in defining sensitive study end points for successful clinical trials of curative or preventive therapeutics. Advances in understanding PML pathophysiology, host and viral genetics, and diagnostics in conjunction with novel immunotherapeutic approaches indicate that the time is right to design and perform definitive trials to develop preventive options and curative therapy for JCV-associated diseases.

Epidemiology of progressive multifocal leukoencephalopathy in Japan and effectiveness of mefloquine: A retrospective analysis of a nationwide inpatient database

INTRODUCTION

Progressive multifocal leukoencephalopathy (PML) is an infrequent yet devastating neurological infection that arises in immunocompromised patients. The epidemiological features of PML in Japan and its evolution in recent years remain unclear. There are no established treatments that directly target PML. Although mefloquine has shown in vitro activity against JC virus, its clinical effectiveness has not been confirmed in population-level studies.

METHODS

We retrospectively analyzed the admission data of patients with PML recorded in the Diagnosis Procedure Combination (DPC) database from fiscal year 2010 to 2020 (11 years). Descriptive statistics were used to illustrate the epidemiological features. Changes in the frequency of PML admission, underlying diseases, and in-hospital mortality over time were also examined. Furthermore, we evaluated the effectiveness of mefloquine in improving activities of daily living at discharge using propensity score matching.

RESULTS

We identified 610 PML cases diagnosed by the treating physicians, which may include possible PML. Among them, 419 were first-time admissions. The median age at admission was 62.0 years, and 62.8% were men. HIV was the most common underlying condition, accounting for 22.9% of cases, followed by hematologic malignancies (18.4%), and autoimmune diseases (17.9%). Over the study period, the frequency of PML admissions showed an increasing trend, whereas the in-hospital mortality rate showed a decreasing trend. The effectiveness of mefloquine was not confirmed.

CONCLUSIONS

The results of this study will help clarify and update the clinical picture of PML in Japan. The DPC database was shown to be useful tool for epidemiological research on rare infectious disease such as PML.

Progressive multifocal leukoencephalopathy in a patient with relapsing multiple sclerosis treated with ocrelizumab: A case report

INTRODUCTION

Progressive multifocal leukoencephalopathy is a rare but often fatal complication of some multiple sclerosis treatments. Although it has mainly been associated with natalizumab treatment, its appearance with other immunosuppressive therapies has also been reported.

AIMS

The aim of this case report is to describe the development of progressive multifocal encephalopathy in a patient with relapsing-remitting multiple sclerosis treated with ocrelizumab without previous use of natalizumab.

CONCLUSIONS

A summary of the presentation and disease course is provided, presented in the context of the current literature and likely pathophysiology.

Revisiting JC virus and progressive multifocal leukoencephalopathy

Since its definition 65 years ago, progressive multifocal leukoencephalopathy (PML) has continued to devastate a growing population of immunosuppressed patients despite major advances in our understanding of the causative JC virus (JCV). Unless contained by the immune system, JCV lyses host oligodendrocytes collateral to its life cycle, leading to demyelination, neurodegeneration, and death. Novel treatments have stagnated in the absence of an animal model while current antiviral agents fail to address the now ubiquitous polyomavirus. In this review, we highlight the established pathogenesis by which JCV infection progresses to PML, highlighting major challenges that must be overcome to eliminate the underlying virus and, therefore, the debilitating disease.

Progressive multifocal leukoencephalopathy: a retrospective study of the last 12 years in a tertiary-care hospital

Our study aims to report on the demographic, incidence rate (IR), clinical, and microbiological characteristics of PML patients diagnosed in our tertiary-care hospital over the past 12 years. In this retrospective observational study, we reviewed all requests for JCPyV PCR in CSF from patients with suspected PML. We collected demographic, clinical, and microbiological data of patients diagnosed with PML. Since 2018, real-time quantitative PCR has been used, whereas prior to 2018, samples were sent to our National Reference Center for qualitative diagnosis. Thirteen patients were diagnosed with PML, with 10 of them having a definitive diagnosis and 3 classified as a possible diagnosis with negative PCR results. Eleven patients had advanced HIV, one had non-Hodgkin's lymphoma, and one had systemic lupus erythematosus. Most of the white matter lesions were located at the cerebral level, although the parenchyma and cerebellum were also affected. The most frequent symptoms were behavioral disorders and hemiparesis. The viral load of JCPyV in cerebrospinal fluid was < 1000 copies/mL in three patients. Six patients received compassionate treatment, and all six patients with definitive PML diagnosis died. Although advanced HIV patients were the most affected by PML in our study, it should also be considered in patients with other underlying diseases. While current PCR tests offer high sensitivity and specificity, false negatives can occur. The prognosis of the disease remains poor, and early multidisciplinary diagnosis-including clinical, microbiological, and neuroimaging assessments-remains crucial for improving neurological damage and prognosis.

Long-term survival from progressive multifocal leukoencephalopathy in living-donor liver transplant recipient with preformed donor-specific antibody

Intensive immunosuppression has enabled liver transplantation even in recipients with preformed donor-specific antibodies (DSA), an independent risk factor for graft rejection. However, these recipients may also be at high risk of progressive multifocal encephalopathy (PML) due to the comorbid immunosuppressed status. A 58-year-old woman presented with self-limited focal-to-bilateral tonic-clonic seizures 9 months after liver transplantation. She was desensitized using rituximab and plasma exchange before transplantation and was subsequently treated with steroids, tacrolimus, and everolimus after transplantation for her preformed DSA. Neurological examination revealed mild acalculia and agraphia. Cranial MRI showed asymmetric, cortex-sparing white matter lesions that increased over a week in the left frontal, left parietal, and right parieto-occipital lobes. Polymerase chain reaction (PCR) of the cerebrospinal fluid for the JC supported the diagnosis of PML. Immune reconstitution by reducing the immunosuppressant dose stopped lesion expansion, and PCR of the cerebrospinal fluid for the JC virus became negative. Graft rejection occurred 2 months after immune reconstitution, requiring readjustment of immunosuppressants. Forty-eight months after PML onset, the patient lived at home without disabling deficits. Intensive immunosuppression may predispose recipients to PML after liver transplantation with preformed DSA. Early immune reconstitution and careful monitoring of graft rejection may help improve outcomes.

Acquired immunodeficiency syndrome-related progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome: prevalence, main characteristics, and outcomes in a Brazilian center

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) - immune reconstitution inflammatory syndrome (IRIS) in people living with HIV/AIDS (PLWHA) has been rarely described in low- and middle-income countries.

OBJECTIVE

To describe the prevalence of PML-IRIS among PLWHA with PML and its main features in a tertiary hospital in Brazil.

METHODS

We performed a retrospective cohort study. We included PLWHA with PML-IRIS patients admitted at Instituto de Infectologia Emílio Ribas, São Paulo, Brazil, between 2011 and 2021. We retrieved information on neurological manifestations, neuroimaging findings, treatments, and outcomes.

RESULTS

We identified 11 (11.8%) PML-IRIS cases among 93 patients with definite PML. Eight (73%) cases were men and had a median (IQR) age of 41 (27-50) years. Seven (63.6%) patients developed unmasking PML-IRIS and 4 (36.4%) had paradoxical PML-IRIS. The median (IQR) time from initiation of combined antiretroviral therapy (cART) to IRIS diagnosis was 49 (30-70) days. Ten (90.9%) patients received corticosteroids. There were 4 (36%) in-hospital deaths and 3 were associated with hospital-acquired pneumonia. Among the 7 (64%) patients who survived, 5 (71.5%) had sequelae at discharge. One year after the PML-IRIS diagnosis, 6 (54.5%) patients were alive.

CONCLUSION

The prevalence of PML-IRIS was 11.8%. Most patients had unmasking PML-IRIS. In-hospital mortality and morbidity were high. One-year survival was similar to that described in some high-income countries.

Progressive multifocal leukoencephalopathy in the background of chlorambucil treated chronic lymphocytic leukemia: a case report from Nepal

Introduction

Progressive multifocal leukoencephalopathy is a rare manifestation in itself. Although many immunosuppressive states are associated with the disease, its occurrence in the setting of chronic lymphocytic leukaemia treated with chemotherapy is seldom reported to date.

Case presentation

A 67-year-old woman with known chronic lymphocytic leukaemia who was previously receiving chlorambucil treatment was identified as having progressive multifocal leukoencephalopathy; her prognosis is currently good.

Clinical discussion

Although a rare disease in an immunocompromised setting, progressive multifocal leukoencephalopathy often leads to a grave outcome. However, the authors describe a case with a good prognosis to date.

Conclusion

Progressive multifocal leukoencephalopathy should be in differentials in immunocompromised patients with dementia. Given that the later prognosis of the disease is unpredictable, an earlier diagnosis would be better for immunological reconstitution.

Serum Neurofilaments are a reliable biomarker to early detect PML in Multiple Sclerosis patients

BACKGROUND

The earliest detection of progressive multifocal leukoencephalopathy (PML) is crucial in Natalizumab (NTZ)-treated Multiple Sclerosis (MS) patients. This study aims to assess serum Neurofilaments (sNFL) ability to early detect PML in longitudinal patients' follow-up.

METHODS

NFL were retrospectively measured in four PML cases occurred at the Regional Referring Center for MS (CRESM, Italy), in samples collected since one year before PML diagnosis, at PML diagnosis, during PML and in post-PML follow-up. sNFL levels were interpreted according to previously defined reference values. Clinical examination and EDSS were performed at each NTZ infusion. Routinary MRI was undertaken every six months; after PML diagnosis, MRI was performed according to clinical evaluation. sNFL were also measured in 45 NTZ-treated patients experiencing NEDA-3 status for at least 12 months.

RESULTS

Patients showed different PML onsets and manifestations: in 3 patients routinary brain MRI revealed radiological signs of PML preceding different clinical manifestations, while in one patient brain MRI was performed after the clinical onset. PML diagnosis was defined at the time of the first detection of JCV DNA in cerebrospinal fluid. The following different PML phases were considered: 1. Basal (up to 4 months before PML diagnosis): sNFL values were in the normal range in all patients' samples, except for one (median 9.1 pg/ml, range 6.2-15.1 pg/ml) 2. Pre-PML (within 3 months before PML diagnosis): sNFL were elevated in all available samples (median 19.50 pg/ml, range 15.50-33.80 pg/ml). 3. PML diagnosis: sNFL were elevated in all patients (median 59.20 pg/ml, range 11.1-101.50 pg/ml). 4. PML/IRIS: during this phase, sNFL levels reached their peak (median 96.35 pg/ml, range 20.5-272.9) in all patients. 5. Post-PML (recovery phase, starting from the first MRI without enhancement, up to the end of follow-up): sNFL levels showed a decrease (median 12.80 pg/ml, range 9.30-30.60); however, based on reference values, sNFL were still elevated in 2 out of 4 patients at the end of their follow-up (622 and 887 days after PML diagnosis). sNFL were always elevated when MRI scan suggested a suspicious of PML. In NEDA-3 patients, sNFL levels were in the normal range in all patients' samples (median 4.7 pg/ml, range 1.4-8.6 pg/ml).

CONCLUSION

Elevated sNFL were observed not only at PML diagnosis, but also in pre-PML phase. At PML recovery, sNFL weren't normalized in all patients' samples, suggesting ongoing neuronal degeneration. sNFL represent a reliable biomarker and should be introduced in clinical practice as an additional/alternative parameter to MRI to early detect and monitor PML.

Progressive multifocal leukoencephalopathy in multiple myeloma: a case report of a patient with SARS-CoV-2 infection and an updated systematic literature review

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by a reactivation of the human polyomavirus 2 (HPyV-2, previously known as JCV) in immunosuppressed individuals. Few cases of PML have been described in multiple myeloma (MM) patients.

METHODS

We described a case of PML in a patient with MM with fatal worsening that occurred during SARS-CoV-2 infection. We also performed a literature review to update the 16 cases series of MM patients with PML already collected until April 2020.

RESULTS

A 79-year-old female patient with refractory IgA lambda MM in Pomalidomide- Cyclophosphamide-Dexamethasone regimen developed gradual lower limbs and left arm paresis along with a decreased consciousness 3.5 years after the MM diagnosis. Symptoms developed shortly after the recognition of hypogammaglobulinemia. After SARS-CoV-2 infection, her neurological status quickly worsened until she deceased. MRI features and JCV-positive PCR on CSF confirmed the PML diagnosis. Our literature review adds sixteen clinical cases of PML in MM published between May 2020 and March 2023 to the 16 cases already collected in the previously published review by Koutsavlis.

DISCUSSION

PML has been increasingly described in MM patients. It remains questionable if the HPyV-2 reactivation is determined by the severity of MM itself, by the effect of drugs or by a combination of both. SARS-CoV-2 infection may have a role in worsening PML in affected patients.

Radiological abnormalities in progressive multifocal leukoencephalopathy: Identifying typical and atypical imaging patterns for early diagnosis and differential considerations

Progressive multifocal leukoencephalopathy (PML) is a rare viral central nervous system (CNS) demyelinating disease primarily associated with a compromised immune system. PML is seen mainly in individuals with human immunodeficiency virus, lymphoproliferative disease, and multiple sclerosis. Patients on immunomodulators, chemotherapy, and solid organ or bone marrow transplants are predisposed to PML. Recognition of various PML-associated typical and atypical imaging abnormalities is critical for early diagnosis and differentiating it from other conditions, especially in high-risk populations. Early PML recognition should expedite efforts at immune-system restoration, allowing for a favorable outcome. This review aims to provide a practical overview of radiological abnormalities in PML patients and address differential considerations.

Adoptive Allogeneic T-Cell Therapy Improves the Clinical Outcome of JC Virus Granule Cell Neuronopathy: A Case Report

OBJECTIVES

JC virus granule cell neuronopathy is a potentially fatal otherwise highly disabling disease without an approved therapeutic option. This case report presents the positive record to T-cell therapy in JC virus granule cell neuronopathy.

METHODS

The patient represented with subacute cerebellar symptoms. Diagnosis of JC virus granule cell neuronopathy was made because of infratentorially accentuated brain volume atrophy shown by brain MRI and the detection of JC virus DNA in the CSF.

RESULTS

Six doses of virus-specific T cells were administered. Within 12 months after therapy initiation, the patient showed clear clinical benefit with improvement of symptoms, and JC viral DNA load significantly declined.

DISCUSSION

We present the case report of a positive response to T-cell therapy in JC virus granule cell neuronopathy, leading to an improvement of symptoms.

Latin American consensus recommendations on the risk of infections in people with multiple sclerosis treated with disease modifying drugs

INTRODUCTION

The emergence of several therapeutic options in multiple sclerosis (MS), which significantly modify the immune system functioning, has led to the need for the consideration of additional factors, such as risk of infections, in the decision-making process. The aim of these consensus recommendations was to discuss and perform a practical guide to Latin American neurologists on the risk of infections at diagnosis, follow-up and prior to initiation of DMDs.

METHODS

A panel of Latin American neurologists, experts in demyelinating diseases and dedicated to management and care of MS patients, gathered during 2021 and 2022 to make consensus recommendations on the risk of infections in PwMS treated with DMDs in Latin America. The RAND/UCLA methodology was developed to synthesize the scientific evidence and expert opinions on health care topics and was used for reaching a formal agreement.

RESULTS

Recommendations were established based on relevant published evidence and expert opinion, focusing on: 1- baseline infection disease and vaccination status; 2- opportunistic infections; 3- progressive multifocal leukoencephalopathy; 4- genitourinary system infections; 5- respiratory tract infections; 6- digestive system infections, 7-others local infections and 8- COVID-19.

CONCLUSION

The recommendations of this consensus seek to optimize the care, management and treatment of PwMS in Latin America. The standardized evidence-based care of pwMS infections will allow better outcomes.

Long-term prognosis and overall mortality in patients with progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a rare but fatal opportunistic infection and mainly occurs in patients with immunosuppressive conditions. Despite the increasing number of patients receiving immunosuppressive treatments, studies on PML are still lacking due to its low prevalence and incidence. We retrospectively reviewed patients diagnosed with PML in two tertiary hospitals in South Korea from 1999 to 2021. Total of 47 PML patients were included. Of 27 patients (57.4%) were diagnosed with human immunodeficiency virus (HIV). Median last follow-up modified Rankin Scale (mRS) score was higher in the non-HIV PML group than that in the HIV group (5 vs. 4, p = 0.020). Median survival duration was lower in the non-HIV group (184 vs. 1,564 days). The 1-year and overall mortality rates of PML patients were significantly higher in the non-HIV group than that in HIV group (60.0% vs. 25.9%, p = 0.019; 80.0% vs. 40.7%, p = 0.007). Initial mRS score (HR 1.685, p = 0.038) and highly active antiretroviral therapy (HAART) in HIV patients (HR 0.374, p = 0.013) had a significant effect on overall mortality. Our findings suggest that early detection of PML with low mRS score and early initiation of HAART in patients with HIV may improve prognosis.

Clinical predictors of encephalitis in UK adults-A multi-centre prospective observational cohort study

OBJECTIVES

Encephalitis, brain inflammation and swelling, most often caused by an infection or the body's immune defences, can have devastating consequences, especially if diagnosed late. We looked for clinical predictors of different types of encephalitis to help clinicians consider earlier treatment.

METHODS

We conducted a multicentre prospective observational cohort study (ENCEPH-UK) of adults (> 16 years) with suspected encephalitis at 31 UK hospitals. We evaluated clinical features and investigated for infectious and autoimmune causes.

RESULTS

341 patients were enrolled between December 2012 and December 2015 and followed up for 12 months. 233 had encephalitis, of whom 65 (28%) had HSV, 38 (16%) had confirmed or probable autoimmune encephalitis, and 87 (37%) had no cause found. The median time from admission to 1st dose of aciclovir for those with HSV was 14 hours (IQR 5-50); time to 1st dose of immunosuppressant for the autoimmune group was 125 hours (IQR 45-250). Compared to non-HSV encephalitis, patients with HSV more often had fever, lower serum sodium and lacked a rash. Those with probable or confirmed autoimmune encephalitis were more likely to be female, have abnormal movements, normal serum sodium levels and a cerebrospinal fluid white cell count < 20 cells x106/L, but they were less likely to have a febrile illness.

CONCLUSIONS

Initiation of treatment for autoimmune encephalitis is delayed considerably compared with HSV encephalitis. Clinical features can help identify patients with autoimmune disease and could be used to initiate earlier presumptive therapy.

Progressive multifocal leukoencephalopathy in an HIV patient: A case report and literature review

Key Clinical Message

Progressive multifocal leukoencephalopathy (PML) is a rare opportunistic infection of the brain caused by reactivation of the JC virus, which can lead to a lytic infection of oligodendrocytes. We report a patient with HIV who developed PML.

Abstract

Progressive multifocal leukoencephalopathy (PML) is a rare opportunistic infection of the brain caused by reactivation of the John Cunningham virus (JCV), which can lead to a lytic infection of oligodendrocytes. Herein, we report the case of a patient with HIV who developed PML that presented as a progressive disturbance of consciousness and movement. The patient's clinical symptoms progressively deteriorated, and positive JC viral DNA in his cerebrospinal fluid (CSF) helped us diagnose him with PML. Magnetic resonance imaging (MRI) showed multiple asymmetric subcortical and deep white-matter lesions. Although we administered immunoreconstructive therapy, the patient's condition gradually worsened. Therefore, we suggest that PML should be considered if such lesions are found in MRIs of HIV patients.

Cerebellar Progressive Multifocal Leukoencephalopathy Mimicking Anti-Yo-Antibody-Associated Rapidly Progressive Cerebellar Syndrome

A 58-year-old woman with a history of systemic lupus erythematosus (SLE) who was taking prednisolone and mycophenolate mofetil presented with gait disturbances that progressively worsened over a period of 3 months. Her blood test and cerebrospinal fluid (CSF) examination results did not indicate active SLE. Initial brain magnetic resonance imaging (MRI) revealed a small spotty lesion in the left cerebellar peduncle. The clinical course was consistent with rapidly progressive cerebellar syndrome (RPCS), which sometimes involves neuronal antibodies. The line blot assay detected anti-Yo antibodies, but no malignancy was found. Immunohistological techniques using rat brain sections yielded a negative result for anti-Yo antibodies. The second MRI revealed a focal lesion and surrounding spotty lesion in the left cerebellar peduncle, which was consistent with the punctate pattern observed in progressive multifocal leukoencephalopathy (PML). The CSF JCV-DNA test indicated the presence of cerebellar PML. Immunosuppressants were reduced, and mefloquine and mirtazapine were initiated. After approximately 2 years and 1 month, the CSF JCV-DNA results became negative. Cerebellar PML may exhibit a clinical course that is consistent with RPCS. The punctate pattern should be recognized as an early manifestation of PML. The CSF JCV-DNA copy number may serve as a useful indicator of PML stabilization.

Secondary Central Nervous System Demyelinating Disorders in the Elderly: A Narrative Review

Secondary demyelinating diseases comprise a wide spectrum group of pathological conditions and may either be attributed to a disorder primarily affecting the neurons or axons, followed by demyelination, or to an underlying condition leading to secondary damage of the myelin sheath. In the elderly, primary demyelinating diseases of the central nervous system (CNS), such as multiple sclerosis, are relatively uncommon. However, secondary causes of CNS demyelination may often occur and in this case, extensive diagnostic workup is usually needed. Infectious, postinfectious, or postvaccinal demyelination may be observed, attributed to age-related alterations of the immune system in this population. Osmotic disturbances and nutritional deficiencies, more commonly observed in the elderly, may lead to conditions such as pontine/extrapontine myelinolysis, Wernicke encephalopathy, and demyelination of the posterior columns of the spinal cord. The prevalence of malignancies is higher in the elderly, sometimes leading to radiation-induced, immunotherapy-related, or paraneoplastic CNS demyelination. This review intends to aid clinical neurologists in broadening their diagnostic approach to secondary CNS demyelinating diseases in the elderly. Common clinical conditions leading to secondary demyelination and their clinical manifestations are summarized here, while the current knowledge of the underlying pathophysiological mechanisms is additionally presented.

Progressive multifocal leukoencephalopathy associated with carbamazepine-induced immune dysfunction and recovery after carbamazepine cessation

A patient with epilepsy on carbamazepine developed a rapidly progressive cerebellar syndrome. Serial MRI showed progressive posterior fossa T2/fluid attenuated inversion recovery hyperintensity with gadolinium enhancement. Standard cerebrospinal fluid (CSF) analysis was normal. Detection of John Cunningham virus DNA in the CSF confirmed progressive multifocal leukoencephalopathy (PML). The only evidence of immune disfunction was hypogammaglobulinaemia and longstanding lymphopenia. After cessation of carbamazepine, the lymphocyte count and immunoglobulin levels returned to normal and the PML resolved, with good clinical recovery. No specific treatments for PML were given. We hypothesise that PML in this case was due to carbamazepine-induced prolonged mild immunosuppression with reconstitution of the immune system after carbamazepine cessation, resulting in recovery from PML. Effects of anticonvulsants on immune function and infection risk may contribute to epilepsy-related morbidity and mortality. Further investigation is needed to determine the frequency of immune dysfunction and infections in patients treated with anticonvulsants such as carbamazepine and whether interventions could reduce infection risk.

Misdiagnosed Progressive Multifocal Leukoencephalopathy (PML) in an HIV-Negative Patient With Discoid Lupus: A Case Report

Progressive multifocal leukoencephalopathy (PML) is a rare fetal disease that has been uprising since the 1980s. Accurate diagnosis can be challenging and requires a thorough clinical suspicion, particularly among individuals who do not have HIV infection. Further diagnostics studies including cerebrospinal fluid analysis are required for DNA polymerase chain reaction (PCR) and if negative, more invasive tests like Brain biopsy are required. Herein, we describe a rare case of a 64-year-old female with a history of discoid lupus for 30 years who was not on any medications and presented to the hospital multiple times with different neurological deficits. The initial diagnosis consistently pointed toward a stroke until a critical turning point when a cerebrospinal fluid sample tested positive for John Cunningham (JC) virus DNA. Unfortunately, by the time the disease was identified, it had already progressed significantly, resulting in the unfortunate demise of the patient. To our knowledge, this represents the second reported case of PML in a patient with discoid lupus who lacks other commonly observed risk factors for the disease. This finding underscores the significance of maintaining clinical attentiveness within this specific patient population.

A safety review of current monoclonal antibodies used to treat multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system. Monoclonal antibodies (mAbs) have shown efficacy in reducing MS relapse rates, disease progression, and brain lesion activity.

AREAS COVERED

This article reviews the literature on the use of mAbs for the treatment of MS, including their mechanisms of action, clinical trial data, safety profiles, and long-term outcomes. The review focuses on the three main categories of mAbs used in MS: alemtuzumab, natalizumab, and anti-CD20 drugs. A literature search was conducted using relevant keywords and guidelines and reports from regulatory agencies were reviewed. The search covered studies published from inception to 31 December 202231 December 2022. The article also discusses the potential risks and benefits of these therapies, including their effects on infection rates, malignancies, and vaccination efficacy.

EXPERT OPINION

Monoclonal antibodies have revolutionized the treatment of MS, but safety concerns must be considered, particularly with regards to infection rates, malignancy risk, and vaccination efficacy. Clinicians must weigh the potential benefits and risks of mAbs on an individual patient basis, taking into account factors such as age, disease severity, and comorbidities. Ongoing monitoring and surveillance are essential to ensure the long-term safety and effectiveness of monoclonal antibody therapies in MS.

Epileptic seizures associated with progressive multifocal leukoencephalopathy in HIV-infected patients in Korea

We investigated the incidence and risk factors of seizures related to progressive multifocal leukoencephalopathy (PML) in Korean patients infected with HIV. Of the 34 patients, 14 (41.2%) developed epileptic seizures during a median follow-up of 82 months. The median time from PML diagnosis to seizure onset was 44 months, ranging from 0 to 133 months. Patients with PML who developed seizures more commonly had cognitive impairment and multiple or diffuse lesions on brain MRI. These findings highlight the increased seizure risk among HIV-infected patients with PML at any stage of the disease, particularly in cases with extensive involvement.

Characteristics of Progressive Multifocal Leukoencephalopathy Associated With Sarcoidosis Without Therapeutic Immune Suppression

Importance

Progressive multifocal leukoencephalopathy can occur in the context of systemic sarcoidosis (S-PML) in the absence of therapeutic immune suppression and can initially be mistaken for neurosarcoidosis or other complications of sarcoidosis. Earlier recognition of S-PML could lead to more effective treatment of the disease.

Objective

To describe characteristics of patients with S-PML.

Design, Setting, and Participants

For this case series, records from 8 academic medical centers in the United States were reviewed from 2004 to 2022. A systematic review of literature from 1955 to 2022 yielded data for additional patients. Included were patients with S-PML who were not receiving therapeutic immune suppression. The median follow-up time for patients who survived the acute range of illness was 19 months (range, 2-99). Data were analyzed in February 2023.

Exposures

Sarcoidosis without active therapeutic immune suppression.

Main Outcomes and Measures

Clinical, laboratory, and radiographic features of patients with S-PML.

Results

Twenty-one patients with S-PML not receiving therapeutic immune suppression were included in this study, and data for 37 patients were collected from literature review. The median age of the 21 study patients was 56 years (range, 33-72), 4 patients (19%) were female, and 17 (81%) were male. The median age of the literature review patients was 49 years (range, 21-74); 12 of 34 patients (33%) with reported sex were female, and 22 (67%) were male. Nine of 21 study patients (43%) and 18 of 31 literature review patients (58%) had simultaneous presentation of systemic sarcoidosis and PML. Six of 14 study patients (43%) and 11 of 19 literature review patients (58%) had a CD4+ T-cell count greater than 200/μL. In 2 study patients, a systemic flare of sarcoidosis closely preceded S-PML development. Ten of 17 study patients (59%) and 21 of 35 literature review patients (60%) died during the acute phase of illness. No meaningful predictive differences were found between patients who survived S-PML and those who did not.

Conclusions and Relevance

In this case series, patients with sarcoidosis developed PML in the absence of therapeutic immune suppression, and peripheral blood proxies of immune function were often only mildly abnormal. Systemic sarcoidosis flares may rarely herald the onset of S-PML. Clinicians should consider PML in any patient with sarcoidosis and new white matter lesions on brain magnetic resonance imaging.