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

Sintilimab for treating progressive multifocal leukoencephalopathy caused by human polyomavirus 2 virus infection following allogeneic hematopoietic cell transplantation: a case report

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) is characterized by demyelination in the central nervous system. It is caused by infection with human polyomavirus 2 and has a poor prognosis. Therapeutic strategies involve restoring immune function and/or discontinuing immunosuppressive treatment. Immune checkpoint inhibitors such as those targeting programmed death receptor-1 (PD-1) can alleviate PML by restoring T cell function. There are no case reports on the use of the PD-1 inhibitor, Sintilimab, for treating PML. Here, we report a case of successful treatment of PML with sintilimab following allogeneic hematopoietic stem cell transplantation.

CASE PRESENTATION

A 35-year-old woman with high-risk acute myeloid leukemia underwent allogeneic hematopoietic stem cell transplantation after induced remission and developed PML 12 months after transplantation. She received five courses of 100 mg every 4 weeks with monitoring by magnetic resonance imaging (MRI) and viral load in the cerebrospinal fluid, showing clinical improvement, resolution of neurological symptoms, and reduced viral load. MRI showed initial exacerbation of lesions but significant improvement after five courses of treatment. No graft-versus-host disease occurred, but manageable immune reconstitution inflammatory syndrome was observed.

CONCLUSION

Sintilimab, a PD-1 inhibitor, might be used to treat PML in patients with hematologic malignancies undergoing allo-HSCT, which needs further investigation.

The microvascular endothelium of the blood-brain barrier is highly restrictive to JC Polyomavirus neuroinvasion

JC Polyomavirus is the causative agent of progressive multifocal leukoencephalopathy (PML), an often-fatal demyelinating disease. Unfortunately, a diagnosis of PML occurs only after patients have suffered irreversible neuropathologies. The first step in the initiation of PML is viral entry to the brain, but the route and mechanisms responsible for neuroinvasion have not been well established. To gain a better understanding of this, we asked whether purified virus or virus associated with extracellular vesicles (EVs) could penetrate two different cell culture models of the blood-brain barrier. In one model, we used the hCMEC/D3 brain endothelial cell line, and in the other, we used pluripotent stem cells induced to a brain endothelial cell phenotype (iPSC-EC). We found that neither cell type was permissive to viral infection, but the virus bound and was internalized by both in a sialic acid-dependent manner. Despite virus internalization into these cells, very few virions or virus-associated extracellular vesicles (virus-EVs) penetrated the barriers. The small amount of virus or virus-EVs that did pass through either barrier was sufficient to establish infection in human glial cells. Our findings demonstrate that limited amounts of infectious virions and virus-associated EVs can traverse the brain microvascular endothelium and establish infection.IMPORTANCEThe human polyomavirus, JC Polyomavirus (JCPyV), causes a rapidly progressing demyelinating disease in immunocompromised or immunomodulated patients. Demyelinating lesions are often seen surrounding blood vessels in the brain. In this paper, we used two models to recapitulate a minimal blood-brain barrier and found that both were highly restrictive of virus penetration. A small amount of virus succeeded in crossing both barriers and was sufficient to establish infection of human glia. These data have direct implications for mechanisms used by JCPyV to invade the CNS and cause neurological disease.

Polyomaviruses After Allogeneic Hematopoietic Stem Cell Transplantation

Polyomaviruses (PyVs) are non-enveloped double-stranded DNA viruses that can cause significant morbidity in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients, particularly BK polyomavirus (BKPyV) and JC polyomavirus (JCPyV). BKPyV is primarily associated with hemorrhagic cystitis (HC), while JCPyV causes progressive multifocal leukoencephalopathy (PML). The pathogenesis of these diseases involves viral reactivation under immunosuppressive conditions, leading to replication in tissues such as the kidney, bladder, and central nervous system. BKPyV-HC presents as hematuria and urinary symptoms, graded by severity. PML, though rare after allo-HSCT, manifests as neurological deficits due to JCPyV replication in glial cells. Diagnosis relies on nucleic acid amplification testing for DNAuria or DNAemia as well as clinical criteria. Management primarily involves supportive care, as no antiviral treatments have proven consistently effective for either virus and need further research. This review highlights the virology, clinical presentations, and management challenges of PyV-associated diseases post-allo-HSCT, emphasizing the need for improved diagnostic tools and therapeutic approaches to mitigate morbidity and mortality in this vulnerable population.

Diagnosing progressive multifocal leukoencephalopathy: Positive predictive value of CSF JC virus quantitative PCR and importance of recognizing suggestive neuroimaging findings

OBJECTIVE

To determine the positive predictive value (PPV) of CSF John Cunningham virus (JCV) quantitative PCR (qPCR) for progressive multifocal leukoencephalopathy (PML), and highlight neuroimaging findings reported to be suggestive of this disease.

METHODS

We reviewed patients at London Health Sciences Centre with a positive CSF JCV qPCR result. Patients were classified as true-positive if they had a clinico-radiographic presentation compatible with PML and no more likely alternative diagnosis. The presence of suggestive neuroimaging findings was documented as supportive evidence of PML. The PPV of CSF JCV qPCR was calculated as the proportion of positive results that were classified as true-positives.

RESULTS

Eleven of 154 patients who underwent CSF JCV qPCR testing had a positive result (7 %). Median age was 60 years (range: 33-79 years) and 7/11 (64 %) were male. Nine of 11 (82 %) were overtly immunocompromised. Five of 11 (45 %) had a viral load below the lowest quantifiable standard (<4290 copies/ml). All had a clinico-radiographic presentation compatible with PML and no more likely alternative diagnosis, resulting in a PPV of 100 %. All had one or more suggestive neuroimaging findings that supported PML diagnosis (Milky Way sign/punctate pattern, 9; rim-and-core pattern, 7; T2/FLAIR mismatch, 6; shrimp sign, 4; SWI-hypointense rim, 2; across-the-pons sign, 1; barbell sign, 1).

CONCLUSIONS

We found that CSF JCV qPCR had high PPV for PML. All positives below the lowest quantifiable standard were true-positives. Our study affirms the diagnostic utility of this testing in clinical practice. Recognition of suggestive neuroimaging findings helps facilitate PML diagnosis.

A spectrum of neurological diseases with elevated cerebrospinal fluid adenosine deaminase levels

OBJECTIVES

This study aimed to investigate cerebrospinal fluid (CSF) adenosine deaminase (ADA) levels in various neurological disorders and examine the relationships between CSF ADA levels and immunological parameters.

METHODS

Overall, 276 patients whose CSF ADA levels were measured for suspected tuberculous meningitis (TBM) were evaluated. Data on baseline characteristics, final diagnoses, CSF ADA levels, and other laboratory parameters were collected. Thereafter, CSF ADA levels were compared based on final diagnoses, and correlations between CSF ADA levels and other CSF and blood laboratory parameters were evaluated.

RESULTS

Five diseases exhibited a significant increase in CSF ADA levels relative to the noninflammatory disease control group (n = 40): (1) TBM (n = 15, p < 0.0001), (2) fungal meningitis (n = 7, p = 0.0400), (3) autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A, n = 7, p < 0.0001), (4) neurosarcoidosis (n = 7, p = 0.0028), and (5) lymphoproliferative disorders (n = 18, p = 0.0001). Strong positive correlations were observed between CSF ADA and CSF parameters, including soluble IL2 receptor (rs = 0.7566, p < 0.0001), albumin (rs = 0.6693, p < 0.0001), lactate dehydrogenase (rs = 0.6452, p < 0.0001), white blood cell count (rs = 0.6035, p < 0.0001), protein (rs = 0.6334, p < 0.0001), and lymphocytes (rs = 0.5954, p < 0.0001).

DISCUSSION

CSF ADA levels were elevated in various inflammatory neurological diseases, especially in TBM, fungal meningitis, GFAP-A, neurosarcoidosis, and lymphoproliferative disorders. CSF ADA levels may reflect T-cell hyperactivation in the central nervous system.

Portable ultra-low-field MRI for progressive multifocal leukoencephalopathy: Case studies, sensitivity, and potential applications

BACKGROUND AND OBJECTIVE

Progressive multifocal leukoencephalopathy (PML) is a severe, disabling infection caused by JC virus reactivation. PML-related disability complicates the MRI monitoring needed to assess treatment interventions in clinical trial or compassionate use settings. Portable ultra-low-field MRI (pULF-MRI) offers a convenient approach when such frequent imaging is needed. We evaluated the potential utility of pULF-MRI as an adjunctive tool for decreasing the burden of clinical study participation and clinical management in PML.

METHODS

We examined paired high-field (HF) and pULF-MRI scans from 11 patients, aged 49 ± 15 years. pULF-MRI images with corresponding HF-MRI were coupled to depict key imaging findings of PML, including three patients with longitudinal evaluations, one with bedside pULF-MRI. The images were then independently assessed by two blinded raters, not involved in image acquisition or initial evaluations, who sequentially rated diagnostic accuracy of pULF-MRI scans compared to the HF-MRI. Longitudinal evaluations were performed for three patients, one with bedside pULF-MRI.

RESULTS

T2-FLAIR lesions were detected with pULF-ULF in all cases when present on HF-MRI. Median sensitivity and specificity were 62% and 100%, respectively. T1WI hypointense areas showed similar performance. Focal volume loss was present in 8/11 HF-MRI scans, with sensitivity and specificity of detection by pULF-MRI of 100% and 94%, respectively. Contrast enhancement was seen in a single case on both pULF- and HF-MRI. Follow-up pULF-MRI showed lesion changes in two cases, and stable findings in one case, consistent with HF-MRI.

DISCUSSION

pULF-MRI shows promise in evaluation and monitoring of PML, showing moderate-to-high accuracy even when evaluations were unaided by HF-MRI. Our results highlight a potential application of pULF-MRI for facilitating participation in PML clinical research and more generally as a way to reduce burden of clinical management for this disabled patient population.

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.

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.

Consensus Statements on Assessments and Vaccinations Prior to Commencement of Advanced Therapies for the Treatment of Inflammatory Bowel Diseases

BACKGROUND

Given the introduction of new advanced therapies for inflammatory bowel diseases (IBDs), expanded risk mitigation strategies are essential.

AIMS

To create a comprehensive set of statements on assessment procedures and vaccinations before starting monoclonal antibodies, Janus kinase (JAK) inhibitors or sphingosine-1-phosphate (S1P) modulators for IBD.

METHODS

We examined literature, guidelines and drug product information regarding vaccination and assessment recommendations for initiating advanced IBD therapies. Using a modified Delphi approach, delegates voted anonymously on the acceptability of these statements prior to and following consensus discussion.

RESULTS

We developed eight statements on the domains of infectious diseases screening, vaccinations and assessments prior to commencing JAK inhibitors and S1P modulators. Six statements received agreement. Pre-advanced therapy screening for infectious diseases was established, and the vaccination protocol was revised. Malignancy, cardiovascular and thromboembolic risk assessments are necessary before initiating JAK inhibitors. Those starting S1P modulators need cardiac and ophthalmic assessments.

CONCLUSIONS

These consensus statements combine vaccination and assessments on the currently available advanced therapies for IBD as a single comprehensive document that may reduce IBD complications associated with use of advanced therapies. Knowledge gaps identified during the consensus process will provide further research opportunities.

Performance of Ultrasensitive Polymerase Chain Reaction Testing for JC Polyomavirus in Cerebrospinal Fluid Compared with Pathological Diagnosis of Progressive Multifocal Leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease caused by the JC polyomavirus (JCPyV). Based on the clinical criteria, PML is diagnosed via polymerase chain reaction (PCR) detection of JCPyV DNA in cerebrospinal fluid (CSF) in combination with neurological and imaging findings. Although the utility of CSF JCPyV testing using ultrasensitive PCR assays has been suggested, its potential requires further evaluation. This study retrospectively analyzed the detection performance of ultrasensitive PCR for CSF JCPyV in patients who underwent brain tissue examination based on the pathological diagnostic criteria for PML. Of the 110 patients with pathologically confirmed definite PML or not PML, standard and ultrasensitive CSF testing was performed for 36 and 74 patients, respectively. The sensitivity of ultrasensitive CSF JCPyV testing of the initial specimens was 85%. With the addition of the follow-up testing, this figure increased to 95%. The specificity and false-positive rate of ultrasensitive CSF JCPyV testing, including follow-up, were 100% and 0%, respectively. No statistically significant correlation was observed between CSF and brain JCPyV levels. The results of this study demonstrate the high sensitivity and accuracy of ultrasensitive CSF JCPyV testing and provide essential information for the clinical diagnosis of PML.

Progressive multifocal leukoencephalopathy associated with sphingosine-1-phosphate receptor modulators: A large case series

BACKGROUND

Risk factors for progressive multifocal leukoencephalopathy (PML) associated with sphingosine-1-phosphate receptor (S1PR) modulators are not as well-characterized as for natalizumab. We characterized S1PR modulator-associated PML cases and risk factors for PML using spontaneous adverse event reports.

METHODS

We reviewed case reports from the FDA Adverse Event Reporting System database and the medical literature.

RESULTS

We identified 57 PML cases encompassing all marketed S1PR modulators approved for multiple sclerosis, the majority (n = 53) associated with fingolimod. Ten cases reported a fatal outcome. Length of S1PR modulator exposure (≥18 months) appears to be a robust risk factor for PML. Patient age ≥50 years was identified as a potential risk factor, although this may be the result of several biases. We propose that prior immunosuppressant exposure should be considered as a potential risk factor for further validation. No conclusions could be drawn regarding JC virus serology and lymphopenia severity.

CONCLUSIONS

Spontaneous adverse event reports support the observation that extended S1PR modulator exposure appears to be a robust PML risk factor. As a result, the U.S. Prescribing Information for each product in the S1PR modulator class was updated. Validation of other potential risk factors would support efforts to stratify and mitigate the risk of S1PR modulator-associated PML.

Brain biopsy and pathological diagnosis for drug-associated progressive multifocal leukoencephalopathy (PML) with inflammatory reactions

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by JC virus (JCV) infection. Although recognized as an AIDS complication in the 1980s, PML has emerged as a serious adverse event of immunosuppressive therapies since 2005, particularly disease-modifying drugs (DMDs) for multiple sclerosis (MS). PML can also occur in patients with collagenous diseases receiving steroid therapy or with age-related immunosuppression. In some cases, the etiology of immunosuppression remains unclear. These cases often present with early manifestations of PML, which, while common, are less well recognized, as PML was identified at more advanced stages in AIDS-related cases. Early diagnosis poses difficulty due to unfamiliar magnetic resonance (MR) images and low viral loads in cerebrospinal fluid (CSF), and brain biopsy may be conducted. This review summarizes the PML pathology identified through biopsy. Early cytopathological changes of JCV-infected cells, with the importance of dot-shaped inclusions associated with promyelocytic leukemia nuclear bodies (PML-NBs), are described. The variability of host immune responses, including PML immune reconstitution inflammatory syndrome (PML-IRIS), is addressed. The potential role of immune checkpoint inhibitors (ICIs), such as pembrolizumab, is also explored. Understanding the pathology of early PML helps to optimize diagnostic strategies and therapeutic interventions, ultimately improving prognosis.

Advances in virus-specific T-cell therapy for polyomavirus infections: A comprehensive review

Polyomaviruses are a group of small, non-enveloped, double-stranded DNA viruses that can infect various hosts, including humans. BKPyV causes conditions such as human polyomavirus-associated nephropathy (HPyVAN), human polyomavirus-associated haemorrhagic cystitis (HPyVHC), and human polyomavirus-associated urothelial cancer (HPyVUC). JC polyomavirus (JCPyV), on the other hand, is the causative agent of progressive multifocal leukoencephalopathy (PML), a severe demyelinating disease of the central nervous system. PML primarily affects immunocompromised individuals, including those with HIV, recipients of certain immunosuppressive therapies, and transplant patients. The treatment options for HPyV infections have been limited, but recent developments in virus-specific T cell (VST) therapy have shown promise. Although VST therapy has shown potential in treating both BKPyV and JCPyV infections, several challenges remain. These include the time-consuming and costly preparation of VSTs, the need for sophisticated production facilities, and uncertainties regarding the optimal cell type and infusion frequency. To the best of our knowledge, 85 patients with haemorrhagic cystitis, 27 patients with BKPyV viremia, 2 patients with BKPyV nephritis, 14 patients with haemorrhagic cystitis and BKPyV viremia, and 32 patients with PML have been treated with VST in the literature. The overall response results were 82 complete response, 33 partial response, 35 no response, and 10 no-outcome-reported. This review underscores the importance of VST therapy as a promising treatment approach for polyomavirus infections, emphasising the need for continued research and clinical trials to refine and expand this innovative immunotherapeutic strategy.

Elevation of serum neurofilament light-chain levels disclose possible occult progressive multifocal leukoencephalopathy and immune reconstitution syndrome in a patient receiving ozanimod: a case report

Background

We report the first case of findings suggestive of progressive multifocal leukoencephalopathy and immune restitution syndrome (PML-IRIS) in a patient with multiple sclerosis receiving ozanimod preceded by an unexpected increase in the serum neurofilament light-chain (sNfL) levels.

Case report

A 57-year-old-woman treated with ozanimod for the last 8 years presented, during surveillance MRI, with findings compatible with PML-IRIS. Overt clinical symptoms were absent. sNfL levels increased 4 months earlier and peaked at presentation. Lymphocyte count reached nadir of 330/mL at 8 months earlier.

Conclusion

The case illustrates the utility of sNfL levels for PML surveillance in patients receiving immunosuppressors.

Directly Isolated Allogeneic Virus-Specific T Cells in Progressive Multifocal Leukoencephalopathy

Importance

Progressive multifocal leukoencephalopathy (PML) is a life-threatening viral infection with no approved antiviral treatment.

Objective

To determine whether restoring the compromised immune system of patients with PML with directly isolated allogeneic virus-specific (DIAVIS) T cells is a promising therapeutic strategy, especially if other curative options are absent.

Design, Setting, and Participants

A retrospective case series of patients with PML who were treated with DIAVIS T cells was conducted between March 2020 and February 2022. T cells were isolated from healthy donors within 24 hours and targeted against the BK polyomavirus. Patients with PML were treated monocentrically. Eligibility for treatment with DIAVIS T cells was assessed for patients with confirmed PML, and exclusion criteria included stable PML disease and previous treatment with natalizumab.

Exposure

Fresh DIAVIS T cells were administered with a maximum dose of 2 × 104 CD3+ cells/kg body weight. Remaining T cells were cryopreserved in divided doses and administered in additional treatments approximately 2 and 6 weeks later.

Main Outcomes and Measures

Primary outcome measures were clinical response and survival of patients, compared with the outcomes of a historical reference group of PML cases receiving best supportive treatment (BST) and with recently published real-world data of patients with PML who were treated with immune checkpoint inhibition.

Results

The study cohort consisted of 28 patients (median [IQR] age, 60 [51-72] years; 20 male [71.4%]). Twenty-two patients (79%) treated with DIAVIS T cells showed response, resulting in significant clinical stabilization or improvement and a reduction in viral load. Six individuals (21%) were classified as nonresponders, deteriorated rapidly, and died, as did 2 other patients during a 12-month follow-up. Older age was the only predictor of a poor treatment response. Survival analysis revealed better 12-month survival rates (hazard ratio, 0.42; 95% CI, 0.24-0.73; P =.02) from diagnosis for patients treated with DIAVIS T cells (18 of 26 [69%]; 12-mo survival rate, 69%) compared with historical controls with BST (57 of 113 [50%]; 12-mo survival rate, including censored data, 45%).

Conclusion and Relevance

This case series of DIAVIS T-cell therapy in PML provides first class IV evidence suggesting efficacy to reduce mortality and improve functional outcome. Further prospective studies are required to confirm these results.

Progressive Multifocal Leukoencephalopathy in a Patient With Cirrhosis and Hepatocellular Carcinoma

The following case describes a constellation of progressive cognitive and motor deficits in a 73-year-old man with cirrhosis and history of early-stage hepatocellular carcinoma confined to his liver. He had deficits in calculation, language, and writing, as well as subtle right-sided weakness. Magnetic resonance imaging (MRI) of the brain demonstrated non-enhancing white matter lesions without mass effect in the bilateral parietal and left occipitotemporal regions, correlating with neurologic exam findings. The patient's basic blood and cerebrospinal fluid (CSF) studies were within normal limits. Our differential included inflammatory and demyelinating conditions, hepatic encephalopathy, posterior reversible encephalopathy syndrome, progressive multifocal leukoencephalopathy (PML), and central nervous system (CNS) tumors. He did not improve with an empiric course of high-dose steroids or adequate hepatic encephalopathy treatment. A repeat lumbar puncture sent for additional CSF studies revealed a positive John Cunningham (JC) virus PCR test, confirming diagnosis of PML. Although the patient did not have any known overt immunosuppressive condition or treatment, the patient's cirrhosis and age placed him at higher risk for developing JC virus CNS reactivation. In a published case series of patients with PML and no classic immunosuppressive condition that includes several patients with concomitant cirrhosis, prognosis is much worse compared to those with known, reversible causes of immunosuppression.

A Case of Progressive Multifocal Leukoencephalopathy Caused by Epcoritamab

A female patient aged in her 50s had presented with the onset of follicular lymphoma (FL) with left mandibular swelling, with a pathological grade of 1 and clinical stage of Ⅳ (Ann Arbor staging). Cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab (R-CHOP) resulted in complete molecular remission (CMR). The patient experienced two recurrences, and treatments were successful; however, the side effect of continuous lymphocytopenia existed eight years after the onset. For the third recurrence of FL, weekly epcoritamab therapy was administered with a white blood cell count of 2,010 /μL with neutrophils of 1,240/μL, lymphocytes of 430/μL, red blood cells of 390 × 104/μL, and platelets of 17.8 × 104/μL. 18Fludeoxyglucose positron emission tomography (FDG-PET) confirmed CMR after six cycles of epcoritamab. After the 11th epcoritamab, the patient was diagnosed with progressive multifocal leukoencephalopathy (PML), presenting significant left hemispatial neglect and visuospatial problems. Brain magnetic resonance imaging of fluid-attenuated inversion recovery and diffusion-weighted imaging showed high intensity in the right parietotemporal subcortex and frontal subcortical lesion with high or iso intensity on the apparent diffusion coefficient. FDG-PET did not show lymphoma recurrence. The patient had white blood cells of 2,310 /μL with lymphocytes of 480/μL, CD4-positive lymphocytes of 124/μL, and CD8-positive lymphocytes of 153/μL. The JC virus (JCV) deoxyribonucleic acid (DNA) level in cerebrospinal fluid (CSF) as examined by polymerase chain reaction (PCR) increased to 1.466 × 108 copies/mL. The patient became unconscious and died three months after diagnosis of PML. We report the first case of PML as a complication of epcoritamab, a bispecific antibody targeting CD3 and CD20 that redirects and activates T cells, which is expected to be used for treating FL. PML is a fatal infection of the central nervous system without effective treatment caused by the reactivation of the JCV in immunodeficient hosts. The antibody test for JCV is recommended for patients with multiple sclerosis for an earlier diagnosis, which is not common in other diseases. We should be aware of PML through innovative therapy.

Posterior Reversible Encephalopathy Syndrome: A Clinico-Radiological Approach

Introduction Posterior reversible encephalopathy syndrome (PRES) is a self-limiting neurological condition usually seen in young to middle-aged adults. Although most cases occur in the context of hypertension, PRES is not uncommon in normotensives. PRES is a clinico-radiological diagnosis that embodies specific clinical features, risk factors, and imaging findings. This study analyzes the clinico-radiological profile, typical and atypical features, and outcomes of patients presenting with PRES. Methodology This prospective observational study spanned 18 months and included 38 patients with suspected PRES who were referred from the neurology department. The patients' brain MRIs were evaluated, and the affected regions and their signal intensity depicted in the T1-weighted, T2-weighted, fluid attenuation inversion recovery (FLAIR), and diffusion-weighted images were recorded. The pattern of involvement, atypical findings, and predisposing factors were examined. Results The subcortical white matter of the parieto-occipital lobes was the most typical area affected. The atypical regions affected were the cerebellum, thalamus, brainstem, and basal ganglia. Three cases exhibited isolated involvement of infratentorial structures. Spinal cord involvement was observed in two cases, of which one demonstrated dorsal cord involvement. Conclusion Most lesions are reversible. Long-term follow-up is recommended in hemorrhagic PRES and PRES with spinal cord involvement. Radiologists should be aware of the risk factors, and atypical clinical and imaging features to enable an early diagnosis and prevent further complications.

"Pardon My Language": The Curious Case of a Bloody Sandwich and the John Cunningham Virus Reactivation in the Era of Immunomodulatory Drugs

Progressive multifocal leukoencephalopathy (PML) is a rare diagnosis associated with high mortality in different clinical settings. PML has been attributed to the reactivation of the John Cunningham (JC) virus (JCV). JCV typically affects patients with HIV/AIDS, solid organ and hematological malignancies, and those under treatment with immunomodulatory drugs (IMiDs) like pomalidomide. Currently, there are a limited number of reported cases of patients with multiple myeloma (MM) who developed PML reported in the literature, and one case report of a patient with MM diagnosed with PML in association with pomalidomide and daratumumab. Here, we describe a case of PML in a patient with MM status post autologous stem cell transplant (ASCT) on maintenance treatment with pomalidomide who presented with cognitive decline and aphasia. In an era of increased access to immunomodulatory therapies, physicians should be able to recognize this potential complication as discontinuation of the medication could be lifesaving.

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.

[Case report and literature review of AIDS-related progressive multifocal leukoencephalopathy diagnosed in a psychiatric department]

A progresszív multifokális leukoencephalopathiát a John Cunningham-vírus reaktiválódása okozza, amely szinte kizárólag immunhiányos betegeknél fordul elő. A betegség tüneteit elsősorban a demyelinisatiós gócok lokalizációja határozza meg; a betegség a kezdeti szakaszban tünetszegény lehet, és a neurológiai tünetek csak később jelennek meg. Diagnosztikájában elsősorban a képalkotó vizsgálatok és a vírus-DNS liquorból történő kimutatása játszik fontos szerepet. Specifikus terápiája nem ismert, a cél az immunrendszer működésének helyreállítása. Kazuisztikánkban egy pszichiátriai osztályon észlelt páciens kórtörténetét ismertetjük, akinek esetében AIDS-hez köthető jobb féltekei progresszív multifokális leukoencephalopathia képe igazolódott. Korai differenciáldiagnosztikai nehézséget jelentettek a páciensnél észlelhető patológiás személyiségjegyek, illetve az élethelyzeti nehézségek és a párkapcsolati veszteség talaján kialakult krízisállapot. Esetünkkel szeretnénk felhívni a figyelmet az immunhiányos betegeknél jelentkező pszichiátriai tünetek fontosságára. Orv Hetil. 2024; 165(33): 1295–1302.

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 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.

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.

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.

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.

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.

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.

Infectious leukoencephalopathies

Leukoencephalopathy from infectious agents may have a rapid course, such as human simplex virus encephalitis; however, in many diseases, it may take months or years before diagnosis, such as in subacute sclerosing panencephalitis or Whipple disease. There are wide geographic distributions and susceptible populations, including both immunocompetent and immunodeficient patients. Many infections have high mortality rates, such as John Cunningham virus and subacute sclerosing panencephalitis, although others have effective treatments if suspected and treated early, such as herpes simplex encephalitis. This chapter will describe viral, bacterial, and protozoal infections, which predominantly cause leukoencephalopathy. We focus on the clinical presentation of these infectious agents briefly covering epidemiology and subtypes of infections. Next, we detail current pathophysiologic mechanisms causing white matter injury. Diagnostic and confirmatory tests are discussed. We cover predominantly MRI imaging features of leukoencephalopathies, and in addition, summarize the common imaging features. Additionally, we detail how imaging features may be used to narrow the differential of a leukoencephalopathy clinical presentation. Lastly, we present an outline of common treatment approaches where available.

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.