Update on PML and PML-IRIS Occurring in Multiple Sclerosis Patients Treated With Natalizumab:

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.

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.

Pathology for severe inflammatory PML with PD1/PD-L1 expression of favorable prognosis: What's a prognostic factor for PML-IRIS?

A 72-year-old woman with dermatomyositis (DM) developed neurological manifestation, and magnetic resonance imaging (MRI) revealed multiple T2/fluid-attenuated inversion recovery (FLAIR)-hyperintense lesions predominantly in the deep white matter of the cerebral hemisphere. Punctate or linear contrast enhancement was observed surrounding the T1-hypointense area. Multiple T2/FLAIR-hyperintense lesions were aligned along with the corona radiata. Malignant lymphoma was first suspected, and a brain biopsy was performed. Pathological investigation suggested the provisional diagnosis of "suspicious of malignant lymphoma." Owing to emergent clinical conditions, high-dose methotrexate (MTX) therapy was conducted, and then T2/FLAIR-hyperintense lesions were dramatically reduced. However, the diagnosis of malignant lymphoma was concerning since multiplex PCR demonstrated clonal restriction of the Ig H gene for B cells and TCR beta genes for T cells. Histopathology revealed the infiltration of both CD4+ and CD8+ T cells, and the CD4+ /CD8+ ratio was 4.0. Moreover, prominent plasma cells were observed, in addition to CD20+ B cells. Atypical cells with enlarged nuclei were present, and they were not hematopoietic but found as glial cells. JC virus (JCV) infection was verified with both immunohistochemistry and in situ hybridization; the final diagnosis was progressive multifocal leukoencephalopathy (PML). The patient was treated with mefloquine and discharged. This case is informative in understanding the host anti-viral response. Variable inflammatory cells were observed, including CD4+ and CD8+ T cells, plasma cells, and a small amount of perivascular CD20+ B cells. PD-1 and PD-L1 expression was observed in lymphoid cells and macrophages, respectively. PML with inflammatory reactions was thought fatal, and autopsy cases of PML with immune reconstitution inflammatory syndrome (IRIS) demonstrated excessive infiltration of only CD8+ T cells. However, this case revealed infiltration of variable inflammatory cells, and a favorable prognosis would be expected under PD-1/PD-L1 immune-checkpoint regulation.

Monoclonal Antibodies: What the Diagnostic Neuroradiologist Needs to Know

Monoclonal antibodies have become increasingly popular as novel therapeutics against a variety of diseases due to their specificity, affinity, and serum stability. Due to the nearly infinite repertoire of monoclonal antibodies, their therapeutic use is rapidly expanding, revolutionizing disease course and management, and what is now considered experimental therapy may soon become approved practice. Therefore, it is important for radiologists, neuroradiologists, and neurologists to be aware of these drugs and their possible different imaging-related manifestations, including expected and adverse effects of these novel drugs. Herein, we review the most commonly used monoclonal antibody-targeted therapeutic agents, their mechanism of action, clinical applications, and major adverse events with a focus on neurologic and neurographic effects and discuss differential considerations, to assist in the diagnosis of these conditions.

The neuroradiology of progressive multifocal leukoencephalopathy: a clinical trial perspective

Progressive multifocal leukoencephalopathy (PML) is an opportunistic infection of the central nervous system caused by the JC virus, which infects white and grey matter cells and leads to irreversible demyelination and neuroaxonal damage. Brain magnetic resonance imaging (MRI), in addition to the clinical presentation and demonstration of JC virus DNA either in the CSF or by histopathology, is an important tool in the detection of PML. In clinical practice, standard MRI pulse sequences are utilized for screening, diagnosis, and monitoring of PML, but validated imaging-based outcome measures for use in prospective, interventional clinical trials for PML have yet to be established. We review the existing literature regarding the use of MRI and positron emission tomography imaging in PML and discuss the implications of PML histopathology for neuroradiology. MRI not only demonstrates the localization and extent of PML lesions, but also mirrors the tissue destruction, ongoing viral spread, and resulting inflammation. Finally, we explore the potential for imaging measures to serve as an outcome in PML clinical trials and provide recommendations for current and future imaging outcome measure development in this area.

Risk of Progressive Multifocal Leukoencephalopathy in Multiple Sclerosis Patient Treated With Natalizumab: A Systematic Review

Natalizumab, a monoclonal antibody acting on alpha4 integrin receptors, is frequently used to treat multiple sclerosis patients. The biggest downside is the risk of development of progressive multifocal leukoencephalopathy, an immune-related condition affecting mainly the central nervous system. The presence of the John Cunningham virus (JCV) and its reactivation is an important factor in the development of progressive multifocal leukoencephalopathy (PML). This study highlights its different proposed mechanism and risk factors strongly related to natalizumab-induced progressive multifocal leukoencephalopathy. The pieces of literature will also be reviewed to look for a relation between the JCV and natalizumab-induced progressive multifocal leukoencephalopathy in multiple sclerosis treated patients.

The articles were searched from three databases and reviewed systematically. The inclusion criteria for this study were patients aged 20-50 years, English language paper, full-text availability, and human studies, whereas articles on patients with AIDS and cancer-related disease prior to natalizumab treatment were excluded.

Out of 6531 articles identified after applying the search strategy on three main databases PubMed, Google Scholar, and ResearchGate, a total of 32 articles were finalized for the review. This study follows the guidelines listed in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist 2009. The data collected from these finalized articles were pertaining to the risk factor related to natalizumab induced progressive multifocal leukoencephalopathy and the mechanism related to its pathogenesis. 

Natalizumab is known to have the potential to cause progressive multifocal leukoencephalopathy in treated patients; here, we evaluate a close relationship of its related risk factors. The articles studied exhibit a close relationship between the length of natalizumab treatment and the presence of the JCV before infusion of natalizumab. From our analysis, it seems that the mechanism related to natalizumab-induced PML is strongly related to antigen-specific T cells and its effects. The frequency of monitoring and vigilance on the management of patients treated with natalizumab will help detect progressive multifocal leukoencephalopathy.

Mild progressive multifocal leukoencephalopathy after switching from natalizumab to ocrelizumab

Objective

To describe the disease course of carryover progressive multifocal leukoencephalopathy (PML) after switching from natalizumab to ocrelizumab in 2 patients with relapsing-remitting MS.

Methods

Two case reports with 1 year of follow-up and retrospective longitudinal measurements of serum neurofilament light (NfL) levels and B-cells.

Results

PML was diagnosed 78 days (case 1) and 97 days (case 2) after discontinuation of natalizumab. Both patients developed mild immune reconstitution inflammatory syndrome (IRIS) despite B-cell depletion caused by ocrelizumab. NfL levels increased in both patients during PML-IRIS. PML-IRIS lesions stabilized after treatment with mefloquine and mirtazapine, followed by methylprednisolone, and both patients continued therapy with ocrelizumab when B-cells started to repopulate.

Conclusions

The clinical course of carryover PML was mild in both patients, suggesting that B-cell depletion possibly did not aggravate PML-IRIS in these 2 patients.

Inflammatory Cerebellar PML with a CD4/CD8 Ratio of 2.9 Showed a Favorable Prognosis in a Patient with Rheumatoid Arthritis

The patient was a 74-year-old woman with rheumatoid arthritis who developed ataxia. MRI revealed T2-hyperintense lesions predominantly in the left middle cerebellar peduncle. Punctate or linear Gd enhancement was also observed on T1-weighted images. A brain biopsy was conducted and the pathology revealed a mild demyelinated lesion. Polymerase chain reaction (PCR) of biopsied brain tissues revealed the presence of JC virus (JCV) DNA, but JCV-infected oligodendroglia-like cells were not apparent on immunohistochemistry. Sensitive in-situ hybridization, however, detected three JCV-positive cells and the infiltration of CD4⁺ and CD8⁺ T cells and plasma cells was also observed. Immunosuppressants were tapered off and mirtazapine and mefloquine administered, resulting in a favorable outcome.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

Association of Progressive Multifocal Leukoencephalopathy Lesion Volume With JC Virus Polymerase Chain Reaction Results in Cerebrospinal Fluid of Natalizumab-Treated Patients With Multiple Sclerosis

Importance

The JC virus (JCV) was named after the first patient to be described with progressive multifocal leukoencephalopathy (PML), John Cunningham. Detection of JC virus DNA in cerebrospinal fluid (CSF) by polymerase chain reaction (PCR), and of specific lesions by brain magnetic resonance imaging (MRI), are both considered essential for the diagnosis of natalizumab-associated PML (NTZ-PML) in patients with multiple sclerosis. However, strict pharmacovigilance by MRI can result in detection of patients with small lesions and undetectable JCV DNA in CSF.

Objective

To investigate the association of PML lesion characteristics on MRI with both qualitative and quantitative JCV PCR results in CSF of patients with NTZ-PML.

Design, Setting and Participants

This was a retrospective, cross-sectional study conducted from January 2007 to December 2014 in patients considered to have NTZ-PML based on a set of predefined criteria. Follow-up was at least 6 months. Data of patients from the Dutch-Belgian NTZ-PML cohort and patients treated at multiple medical centers in Belgium and the Netherlands and selected for research purposes were included as a convenience sample.

Main Outcomes and Measures

Brain MRI scans were analyzed for PML lesion volume, location, dissemination, and signs of inflammation. Associations of the qualitative and quantitative CSF JCV PCR results with PML MRI characteristics were calculated.

Results

Of the 73 patients screened, 56 were included (37 were women). At inclusion, 9 patients (16.1%) had undetectable JCV DNA in CSF. Patients with a positive PCR had larger total PML lesion volumes than those with undetectable JCV DNA (median volume, 22.9 mL; interquartile range, 9.2-60.4 mL vs median volume, 6.7 mL; interquartile range, 4.9-14.7 mL; P = .008), and logistic regression showed that a lower PML lesion volume significantly increased the probability for undetectable JCV DNA. There was a positive correlation between PML lesion volume and JCV copy numbers (Spearman ρ, 0.32; P = .03). Progressive multifocal leukoencephalopathy lesion volume was higher in patients with PML symptoms and in patients with more widespread lesion dissemination. No association was found between PCR results and PML lesion dissemination, signs of inflammation, or PML symptoms.

Conclusions and Relevance

Smaller NTZ-PML lesions are associated with a higher likelihood of undetectable JCV DNA in CSF. This may preclude a formal diagnosis of PML and can complicate patient treatment in patients with small MRI lesions highly suggestive of PML detected early through pharmacovigilance.

Development of demyelinating lesions in progressive multifocal leukoencephalopathy (PML): Comparison of magnetic resonance images and neuropathology of post-mortem brain

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disorder caused by opportunistic infection of JC polyomavirus (JCV). Today, increased attention has been focused on PML development in multiple sclerosis (MS) patients under disease-modifying therapies (DMT). Although in the acquired immunodeficiency syndrome (AIDS) era, PML was thought to be a rapidly progressive disease with poor prognosis, drug-associated PML is relatively slow in progress, and a favorable outcome may be expected with early diagnosis. However, early PML diagnosis on magnetic resonance imaging (MRI) is frequently difficult, and JCV DNA copy number in cerebrospinal fluid (CSF) is usually low. To facilitate early PML diagnosis on MRI, the pre-mortem images were compared with neuropathology of the post-mortem brain, and underlying pathology corresponding to the MRI findings was evaluated. As a result, PML lesions of the autopsied brain were divided into three parts, based on the disease extension patterns: (A) Progressive white matter lesion in the right frontoparietal lobe including the precentral gyrus. Huge demyelinated lesions were formed with fusions of numerous small lesions. (B) Central lesion including deep gray matters, such as the putamen and thalamus. The left thalamic lesion was contiguous with the pontine tegmentum. (C) Infratentorial lesion of brainstem and cerebellum. Demyelination in the pontine basilar region and in cerebellar white matter was contiguous via middle cerebellar peduncles (MCPs). In addition, (D) satellite lesions were scattered all over the brain. These observations indicate that PML lesions likely evolve with three steps in a tract-dependent manner: (1) initiation; (2) extension/expansion of demyelinating lesions; and (3) fusion. Understanding of the PML disease evolution patterns would enable confident early diagnosis on MRI, which is essential for favorable prognosis with good functional outcome.

Practical Evidence-Based Recommendations for Patients with Multiple Sclerosis Who Want to Have Children

Multiple sclerosis (MS) management presently aims to reach a state of no (or minimal) evidence of disease activity. The development and commercialization of new drugs has led to a renewed interest in family planning, since patients with MS may face a future with reduced (or no) disease-related neurological disability. The advice of neurologists is often sought by patients who want to have children and need to know more about disease control at conception and during pregnancy and the puerperium. When MS is well controlled, the simple withdrawal of drugs for patients who intend to conceive is not an option. On the other hand, not all treatments presently recommended for MS are considered safe during conception, pregnancy and/or breastfeeding. The objective of the present study was to summarize the practical and evidence-based recommendations for family planning when our patients (women and men) have MS.Funding TEVA Pharmaceutical Brazil.

Inflammatory natalizumab-associated PML: baseline characteristics, lesion evolution and relation with PML-IRIS

BACKGROUND AND OBJECTIVE

Natalizumab-associated progressive multifocal leukoencephalopathy (NTZ-PML) patients may show imaging signs suggestive of inflammation at diagnosis ('inflammatory PML'), reminiscent of PML-immune reconstitution inflammatory syndrome (PML-IRIS). We investigated the imaging characteristics of inflammatory NTZ-PML lesions and PML-IRIS to determine differentiating and overlapping features.

METHODS

We scored the presence, localisation and pattern of imaging characteristics of inflammation on brain MRI scans of inflammatory NTZ-PML patients. The imaging characteristics were followed up until the occurrence of PML-IRIS.

RESULTS

Ten out of the 44 NTZ-PML patients included showed signs suggestive of inflammation at the time of diagnosis. The inflammation pattern at diagnosis was similar to the pattern seen at PML-IRIS, with contrast enhancement representing the most frequent sign of inflammation (90% at diagnosis, 100% at PML-IRIS). However, the severity of inflammation differed, with absence of swelling and low frequency of perilesional oedema (10%) at diagnosis, as compared with the PML-IRIS stage (40%).

CONCLUSION

Patterns of inflammation at the time of PML diagnosis and at the PML-IRIS stage overlap but differ in their severity of inflammation. This supports histopathological evidence that the inflammation seen at both stages of the same disease shares a similar underlying pathophysiology, representing the immune response to the JC virus to a variable extend.

Multiple sclerosis and HIV: a case of multiple sclerosis-immune reconstitution inflammatory syndrome associated with antiretroviral therapy initiation

Studies have suggested that the incidence of multiple sclerosis (MS) in HIV-infected (HIV+) patients is lower than that of the general population. Here, we present a case of MS in an HIV+ patient with a relatively suppressed CD4 cell count who developed clinical and radiographic disease worsening in the setting of antiretroviral therapy (ART) initiation. A 47-year-old HIV+ woman (CD4 cell count 216 cells/µl) presented with decreased vision in her right eye. Magnetic resonance imaging (MRI) revealed optic nerve enhancement and open ring-enhancing lesions in the brain concerning for demyelinating disease. Cerebrospinal fluid was tested extensively for infection and malignancy with no abnormal findings. She received five days of intravenous methylprednisolone. Nine days later, she was restarted on ART. Three weeks later, she was readmitted with left eye vision loss and left hemiplegia (CD4 cell count 342 cells/µl). Repeat imaging showed multiple new enhancing lesions. Several cases have described severe MS relapses and unusually widespread demyelinating lesions on MRI after withdrawal of immunosuppressive drugs. We posit that the clinical and radiographic progression that occurred in our patient after initiation of ART represented an immune reconstitution response to ART. Caution may be warranted when initiating ART in HIV+ patients with suppressed CD4 cell count and active MS.

Magnetic resonance imaging changes following natalizumab discontinuation in multiple sclerosis patients with progressive multifocal leukoencephalopathy

BACKGROUND

Detecting early progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome (PML-IRIS) is clinically relevant.

OBJECTIVE

Evaluating magnetic resonance imaging (MRI) changes following natalizumab (NTZ) discontinuation and preceding PML-IRIS.

METHODS

MRIs (including diffusion-weighted imaging (DWI), T2-weighted fluid-attenuated inversion recovery (T2-FLAIR), post-contrast T1-weighted sequences) were performed every week following PML diagnosis in 11 consecutive NTZ-PML patients. PML expansion, punctate lesions, contrast-enhancement, and mass-effect/edema were evaluated on each MRI sequence, following NTZ discontinuation.

RESULTS

PML-IRIS occurred from 26 to 89 days after NTZ discontinuation. MRI changes prior to early PML-IRIS appeared significantly more pronounced using DWI compared to T2-FLAIR imaging (p < 0.003). Two DWI features (marked PML expansion, punctate lesions) systematically preceded contrast-enhancement.

CONCLUSION

Subtle changes may occur on DWI preceding contrast-enhancement.

Update on monitoring and adverse effects of approved second-generation disease-modifying therapies in relapsing forms of multiple sclerosis

PURPOSE OF REVIEW

There has been a considerable increase in the number of disease-modifying therapies (DMTs) in recent years. It appears that the number of approved DMTs is going to continue to increase in the coming years. The growing number of DMTs has provided a challenge to the clinician to tailor their therapeutic recommendations based on patients' needs and preferences. To choose between these DMTs, knowledge of side-effect profiles is imperative.

RECENT FINDINGS

Alemtuzumab, a humanized recombinant monoclonal antibody, was recently approved for the management of relapsing forms of multiple sclerosis. Its use seems to be limited by significant adverse effects and regular monitoring requirement. In 2014, the first case of progressive multifocal leukoencephalopathy (PML) was diagnosed in a patient with relapsing remitting multiple sclerosis who received extended dimethyl fumarate without any significant confounding factors. Among patients receiving fingolimod after previous natalizumab treatment, there have been 17 suspected cases of PML. There have also been three confirmed cases of PML in individuals who received fingolimod without previous natalizumab treatment.

SUMMARY

In this review, we outline the potential adverse effects and recommended laboratory studies as part of the monitoring strategy following initiation of various DMTs.

Pathologic Findings of Chronic PML-IRIS in a Patient with Prolonged PML Survival Following Natalizumab Treatment

Immune reconstitution inflammatory syndrome (IRIS) is a common complication during treatment for natalizumab-associated progressive multifocal leukoencephalopathy (PML). Although severe IRIS can result in acute worsening of disability and is associated with poor prognosis, effective immune reconstitution may account for the high survival rate of this cohort of PML patients. We present pathological evidence of chronic IRIS 3.5 years after diagnosis with natalizumab-associated PML. Our case showed that the IRIS initially developed after plasma exchange therapy and resolved clinically and radiologically following a combination treatment with corticosteroids, maraviroc, and cidofovir. Autopsy 3.5 years later revealed evidence of grey-white matter junction demyelinating lesions characteristic of PML and perivascular leukocyte infiltrates predominated by CD8⁺ T-lymphocytes, and polymerase chain reaction analysis demonstrated the presence of JC viral DNA in this tissue, indicative of persistent PML-IRIS. While clinical symptoms of PML-IRIS typically stabilize within 6 months, our case report suggests that prolonged low-grade inflammation may persist in some patients. Better assays are needed to determine the prevalence of prolonged low-grade IRIS among PML survivors.

Insight into Metabolic 1H-MRS Changes in Natalizumab Induced Progressive Multifocal Leukoencephalopathy Brain Lesions

Background

Progressive multifocal leukoencephalopathy (PML) is a severe complication of immunosuppressive therapies, especially of natalizumab in relapsing–remitting multiple sclerosis (MS). Metabolic changes within PML lesions have not yet been described in natalizumab-associated PML in MS patients.

Objective

To study metabolic profiles in natalizumab-associated PML lesions of MS patients by ¹H magnetic resonance spectroscopy (¹H-MRS) at different stages during the PML course. To assess changes associated with the occurrence of the immune reconstitution inflammatory syndrome (IRIS).

Methods

20 patients received ¹H-MRS and imaging at 3 T either in the pre-IRIS, IRIS, early-post-PML, or late post-PML setting. Five of these patients received individual follow-up examinations, including the pre-IRIS or IRIS phase. Clinical worsening was described by changes in the Karnofsky Performance Scale (KPS) and the expanded disability status scale (EDSS) 1 year before PML and scoring at the time of ¹H-MRS.

Results

In PML lesions, increased levels of the Lip/Cr ratio, driven by rising of lipid and reduction of Creatine, were found before the occurrence of IRIS (p = 0.014) with a maximum in the PML–IRIS group (p = 0.004). By contrast, marked rises of Cho/Cr in PML lesions were detected exclusively during the IRIS phase (p = 0.003). The Lip/Cr ratio decreased to above-normal levels in early-post-PML (p = 0.007, compared to normal appearing white matter (NAWM)) and to normal levels in the late-post-PML group. NAA/Cho was reduced compared to NAWM in the pre-IRIS, IRIS, and early-post-PML group. In NAA/Cr, the same effect was seen in the pre-IRIS and early-post-PML group. These cross-sectional results were confirmed by the individual follow-up examinations of four patients. NAA/Cho, Cho/Cr, and the lipid rise relative to NAWM in PML lesions were significantly correlated with the residual clinical worsening (KPS change) in post-PML patients (Spearman correlations ρ = 0.481, p = 0.018; ρ = −0.505, p = 0.014; and ρ = −0.488, p = 0.020).

Conclusion

¹H-MRS detected clinically significant dynamic changes of metabolic patterns in PML lesions during the course of natalizumab-associated PML in MS patients. Lip/Cr and Cho/Cr may provide additional information for detecting the onset of the IRIS phase in the course of the PML disease.

Safety concerns and risk management of multiple sclerosis therapies

Currently, more than ten drugs have been approved for treatment of relapsing-remitting multiple sclerosis (MS). Newer treatments may be more effective, but have less favorable safety record. Interferon-β preparations and glatiramer acetate treatment require frequent subcutaneous or intramuscular injections and are only moderately effective, but have very rarely life-threatening adverse effects, whereas teriflunomide and dimethyl fumarate are administered orally and have equal or better efficacy, but have more potentially severe adverse effects. The highly effective therapies fingolimod, natalizumab, daclizumab, and alemtuzumab have more serious adverse effects, some of which may be life-threatening. The choice between drugs should be based on a benefit-risk evaluation and tailored to the individual patient's requirements in a dialogue between the patient and treating neurologist. Patients with average disease activity can choose between dimethyl fumarate and teriflunomide or the "old injectable." Patients with very active MS may choose a more effective drug as the initial treatment. In case of side effects on one drug, switch to another drug can be tried. Suboptimal effect of the first drug indicates escalation to a highly efficacious drug. A favorable benefit-risk balance can be maintained by appropriate patient selection and appropriate risk management on therapy. New treatments will within the coming 1-2 years change our current treatment algorithm for relapsing-remitting MS.

Neurological safety of fingolimod: An updated review

Fingolimod (FTY) is the first oral medication approved for treatment of relapsing–remitting multiple sclerosis (RRMS). Its effectiveness and safety were confirmed in several phase III clinical trials, but proper evaluation of safety in the real patient population requires long‐term post‐marketing monitoring. Since the approval of FTY for RRMS in Japan in 2011, it has been administered to approximately 5000 MS patients, and there have been side‐effect reports from 1750 patients. Major events included infectious diseases, hepatobiliary disorders, nervous system disorders and cardiac disorders. In the present review, we focus especially on central nervous system adverse events. The topics covered are: (i) clinical utility of FTY; (ii) safety profile; (iii) post‐marketing adverse events in Japan; (iv) white matter (tumefactive) lesions; (v) rebound after FTY withdrawal; (vi) relationship between FTY and progressive multifocal leukoencephalopathy; (vii) FTY and progressive multifocal leukoencephalopathy‐related immune reconstitution inflammatory syndrome; and (viii) neuromyelitis optica and leukoencephalopathy.

[Immune reconstitution inflammatory syndrome and rebound syndrome in multiple sclerosis patients who stopped disease modification therapy: current understanding and a case report]

More and more multiple sclerosis patients have been receiving treatment with new immunomodulatory drugs. Its discontinuation because of side-effects, lack of efficacy or pregnancy has been increasing as well. This paper reviews such severe complications of natalizumab and fingolimod cessation as immune reconstitution inflammatory syndrome (IRIS) and rebound. The short history, immunopathogenesis and diagnostic criteria of IRIS in individuals with human immunodeficiency virus infection are covered. Clinical and radiological presentations as well as possible pathogenic mechanisms of IRIS in patients treated with natalizumab and fingolimod are discussed. The authors also report the case of a woman with multiple sclerosis treated with fingolimod, who experienced a severe relapse when she stopped treatment. Diagnostic criteria and prognostic factors for IRIS and rebound are needed in patients with multiple sclerosis who discontinue the new disease modification therapy.

Neurotherapeutic Strategies for Multiple Sclerosis

Multiple sclerosis (MS) is the most common disabling neurologic disease of young adults. There are now 16 US Food and Drug Administration (FDA)-approved disease-modifying therapies for MS as well as a cohort of other agents commonly used in practice when conventional therapies prove inadequate. This article discusses approved FDA therapies as well as commonly used practice-based therapies for MS, as well as those therapies that can be used in patients attempting to become pregnant, or in patients with an established pregnancy, who require concomitant treatment secondary to recalcitrant disease activity.

Current and Emerging Therapies in Multiple Sclerosis: Implications for the Radiologist, Part 2-Surveillance for Treatment Complications and Disease Progression

An understanding of the new generation of MS drugs in conjunction with the key role MR imaging plays in the detection of disease progression, opportunistic infections, and drug-related adverse effects is of vital importance to the neuroradiologist. Part 1 of this review outlined the current treatment options available for MS and examined the mechanisms of action of the various medications. It also covered specific complications associated with each form of therapy. Part 2, in turn deals with the subject of pharmacovigilance and the optimal frequency of MRI monitoring for each individual patient, depending on his or her unique risk profile. Special attention is given to the diagnosing of progressive multifocal leukoencephalopathy in patients treated with natalizumab as this is a key area in which neuroradiologists can contribute to improved patient outcomes. This article also outlines the aims of treatment and reviews the possibility of "no evidence of disease activity" becoming a treatment goal with the availability of more effective therapies. Potential future areas and technologies including image subtraction, brain volume measurement and advanced imaging techniques such as double inversion recovery are also reviewed. It is anticipated that such advancements in this rapidly developing field will improve the accuracy of monitoring an individual patient's response to treatment.

Differences in T cell cytotoxicity and cell death mechanisms between progressive multifocal leukoencephalopathy, herpes simplex virus encephalitis and cytomegalovirus encephalitis

During the appearance of human immunodeficiency virus infection in the 1980 and the 1990s, progressive multifocal leukoencephalopathy (PML), a viral encephalitis induced by the JC virus, was the leading opportunistic brain infection. As a result of the use of modern immunomodulatory compounds such as Natalizumab and Rituximab, the number of patients with PML is once again increasing. Despite the presence of PML over decades, little is known regarding the mechanisms leading to death of infected cells and the role the immune system plays in this process. Here we compared the presence of inflammatory T cells and the targeting of infected cells by cytotoxic T cells in PML, herpes simplex virus encephalitis (HSVE) and cytomegalovirus encephalitis (CMVE). In addition, we analyzed cell death mechanisms in infected cells in these encephalitides. Our results show that large numbers of inflammatory cytotoxic T cells are present in PML lesions. Whereas in HSVE and CMVE, single or multiple appositions of CD8⁺ or granzyme-B⁺ T cells to infected cells are found, in PML such appositions are significantly less apparent. Analysis of apoptotic pathways by markers such as activated caspase-3, caspase-6, poly(ADP-ribose) polymerase-1 (PARP-1) and apoptosis-inducing factor (AIF) showed upregulation of caspase-3 and loss of caspase-6 from mitochondria in CMVE and HSVE infected cells. Infected oligodendrocytes in PML did not upregulate activated caspase-3 but instead showed translocation of PARP-1 from nucleus to cytoplasm and AIF from mitochondria to nucleus. These findings suggest that in HSVE and CMVE, cells die by caspase-mediated apoptosis induced by cytotoxic T cells. In PML, on the other hand, infected cells are not eliminated by the immune system but seem to die by virus-induced PARP and AIF translocation in a type of cell death defined as parthanatos.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice-Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Seventh Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.

Natalizumab-Related Progressive Multifocal Leukoencephalopathy-Immune Reconstitution Inflammatory Syndrome: A Case Report Highlighting Clinical and MRI Features

Multiple sclerosis (MS) patients treated with natalizumab often face the uncommon but severe complication of developing progressive multifocal leukoencephalopathy (PML). PML may be further complicated by immune reconstitution inflammatory syndrome (IRIS) after the removal of the drug. Since both PML and IRIS are associated with high morbidity and mortality rates, early clinical and radiological diagnosis of these complications is of paramount importance. Here, we report a case of an adult male patient who was diagnosed with PML after receiving natalizumab therapy for 6 years for the treatment of MS. Upon cessation of natalizumab, he presented with a paradoxical worsening of clinical and radiological findings consistent with an inflammatory brain injury due to IRIS. He was treated with high dose corticosteroid therapy followed by a gradual improvement in clinical and imaging findings. This article illustrates the magnetic resonance imaging (MRI) features of natalizumab-associated PML-IRIS, along with a brief overview of its clinical features, complications and management strategies.

MRI criteria differentiating asymptomatic PML from new MS lesions during natalizumab pharmacovigilance

OBJECTIVE

Differentiation between progressive multifocal leukoencephalopathy (PML) and new multiple sclerosis (MS) lesions on brain MRI during natalizumab pharmacovigilance in the absence of clinical signs and symptoms is challenging but is of substantial clinical relevance. We aim to define MRI characteristics that can aid in this differentiation.

METHODS

Reference and follow-up brain MRIs of natalizumab-treated patients with MS with asymptomatic PML (n=21), or asymptomatic new MS lesions (n=20) were evaluated with respect to characteristics of newly detected lesions by four blinded raters. We tested the association with PML for each characteristic and constructed a multivariable prediction model which we analysed using a receiver operating characteristic (ROC) curve.

RESULTS

Presence of punctate T2 lesions, cortical grey matter involvement, juxtacortical white matter involvement, ill-defined and mixed lesion borders towards both grey and white matter, lesion size of >3 cm, and contrast enhancement were all associated with PML. Focal lesion appearance and periventricular localisation were associated with new MS lesions. In the multivariable model, punctate T2 lesions and cortical grey matter involvement predict for PML, while focal lesion appearance and periventricular localisation predict for new MS lesions (area under the curve: 0.988, 95% CI 0.977 to 1.0, sensitivity: 100%, specificity: 80.6%).

INTERPRETATION

The MRI characteristics of asymptomatic natalizumab-associated PML lesions proved to differ from new MS lesions. This led to a prediction model with a high discriminating power. Careful assessment of the presence of punctate T2 lesions, cortical grey matter involvement, focal lesion appearance and periventricular localisation allows for an early diagnosis of PML.

Drug-Induced Progressive Multifocal Leukoencephalopathy: A Comprehensive Analysis of the WHO Adverse Drug Reaction Database

OBJECTIVE

To identify safety signals concerning the association between the use of various drug classes and the onset of progressive multifocal leukoencephalopathy (PML).

METHODS

All reports containing suspected or interacting PML-related or leukoencephalopathy-related drugs, held in the World Health Organization spontaneous individual case safety reports database as at 1 September 2014, were retrieved. We identified safety signals by analysing the drug-reaction pairs, using the reporting odds ratio as a measure of disproportionality. A safety signal was defined if a drug was reported more than twice in PML cases with a reporting odds ratio >2 and a lower 95 % confidence limit >1.

RESULTS

We retrieved 2452 reports associated with PML (N = 1612), leukoencephalopathy (N = 835) or both (N = 5), corresponding to 343 different drugs. PML was reported similarly in male and female adults (18-64 years), and almost 30 % of the cases had a fatal outcome. The most frequent Anatomical Therapeutic Chemical (ATC) classification groups concerned antineoplastic agents (23.5 %), antivirals for systemic use (10.1 %) or immunostimulants (4.6 %). Significant disproportionality was found for 88 drugs in the overall analysis (of cases with 'progressive multifocal leukoencephalopathy' or 'leukoencephalopathy' as the Preferred Term), and a new safety signal was identified for 59 active substances (e.g. muromonab-CD3, basiliximab and antithymocyte Ig), as no information on a possible risk of PML was acknowledged in their Summary of Product Characteristics documents. Some safety signals were confirmed also after sensitivity analysis adjustment for several confounding factors (underlying diseases and considering only 'progressive multifocal leukoencephalopathy' as the Preferred Term).

CONCLUSION

We report a possible association between several drugs and PML that has not been previously described. In addition, we have confirmed previously reported signals in a number of drugs. We highlight the need for follow-up by regulatory agencies.

MRI characteristics of early PML-IRIS after natalizumab treatment in patients with MS

OBJECTIVE

The early detection of MRI findings suggestive of immune reconstitution inflammatory syndrome (IRIS) in natalizumab-associated progressive multifocal leukoencephalopathy (PML) is of crucial clinical relevance in terms of treatment decision-making and clinical outcome. The aim of this study was to investigate the earliest imaging characteristics of PML-IRIS manifestation in natalizumab-treated patients with multiple sclerosis and describe an imaging pattern that might aid in the early and specific diagnosis.

METHODS

This was a retrospective study assessing brain MRI of 26 patients with natalizumab-associated PML presenting with lesions suggestive of PML-IRIS during follow-up. MRI findings were evaluated considering the imaging findings such as mass effect, swelling, contrast enhancement, new perivascular T2 lesions and signs suggestive of meningeal inflammation.

RESULTS

Contrast enhancement was the most common imaging sign suggestive of PML-IRIS, seen in 92.3% of the patients (with patchy and/or punctuate pattern in 70.8% and 45.8% respectively), followed by new T2 lesions with a perivascular distribution pattern (34.6%). In those patients with contrast enhancement, the enhancement was present in the lesion periphery in 95.8% of the patients. Contrast-enhancing lesions with a perivascular distribution pattern outside of the PML lesion were observed in 33.3% of the patients. The most common overall pattern was contrast enhancement in the border of the PML lesion with either a patchy or punctuate appearance in 88.5% of all patients.

CONCLUSIONS

Contrast enhancement is the most common earliest sign of natalizumab-associated PML-IRIS with a frequent imaging pattern of contrast-enhancing lesions with either a patchy or punctuate appearance in the border of the PML lesion.

Drug-associated progressive multifocal leukoencephalopathy: a clinical, radiological, and cerebrospinal fluid analysis of 326 cases

The implementation of a variety of immunosuppressive therapies has made drug-associated progressive multifocal leukoencephalopathy (PML) an increasingly prevalent clinical entity. The purpose of this study was to investigate its diagnostic characteristics and to determine whether differences herein exist between the multiple sclerosis (MS), neoplasm, post-transplantation, and autoimmune disease subgroups. Reports of possible, probable, and definite PML according to the current diagnostic criteria were obtained by a systematic search of PubMed and the Dutch pharmacovigilance database. Demographic, epidemiologic, clinical, radiological, cerebrospinal fluid (CSF), and histopathological features were extracted from each report and differences were compared between the disease categories. In the 326 identified reports, PML onset occurred on average 29.5 months after drug introduction, varying from 14.2 to 37.8 months in the neoplasm and MS subgroups, respectively. The most common overall symptoms were motor weakness (48.6 %), cognitive deficits (43.2 %), dysarthria (26.3 %), and ataxia (24.1 %). The former two also constituted the most prevalent manifestations in each subgroup. Lesions were more often localized supratentorially (87.7 %) than infratentorially (27.4 %), especially in the frontal (64.1 %) and parietal lobes (46.6 %), and revealed enhancement in 27.6 % of cases, particularly in the MS (42.9 %) subgroup. Positive JC virus results in the first CSF sample were obtained in 63.5 %, while conversion after one or more negative outcomes occurred in 13.7 % of cases. 52.2 % of patients died, ranging from 12.0 to 83.3 % in the MS and neoplasm subgroups, respectively. In conclusion, despite the heterogeneous nature of the underlying diseases, motor weakness and cognitive changes were the two most common manifestations of drug-associated PML in all subgroups. The frontal and parietal lobes invariably constituted the predilection sites of drug-related PML lesions.

CNS infections in patients with hematological disorders (including allogeneic stem-cell transplantation)-Guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

Diagnosis of CNS infections remains a great challenge in patients with hematological disorders since symptoms might both be masked and be mimicked by other conditions such as metabolic disturbances or consequences from antineoplastic treatment. Thus, awareness of this complication is crucial and any suspicion of a CNS infection should lead to timely and adequate diagnostics and treatment to improve the outcome in this population.

Infections of the central nervous system (CNS) are infrequently diagnosed in immunocompetent patients, but they do occur in a significant proportion of patients with hematological disorders. In particular, patients undergoing allogeneic hematopoietic stem-cell transplantation carry a high risk for CNS infections of up to 15%. Fungi and Toxoplasma gondii are the predominant causative agents. The diagnosis of CNS infections is based on neuroimaging, cerebrospinal fluid examination and biopsy of suspicious lesions in selected patients. However, identification of CNS infections in immunocompromised patients could represent a major challenge since metabolic disturbances, side-effects of antineoplastic or immunosuppressive drugs and CNS involvement of the underlying hematological disorder may mimic symptoms of a CNS infection. The prognosis of CNS infections is generally poor in these patients, albeit the introduction of novel substances (e.g. voriconazole) has improved the outcome in distinct patient subgroups. This guideline has been developed by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) with the contribution of a panel of 14 experts certified in internal medicine, hematology/oncology, infectious diseases, intensive care, neurology and neuroradiology. Grades of recommendation and levels of evidence were categorized by using novel criteria, as recently published by the European Society of Clinical Microbiology and Infectious Diseases.

Progressive multifocal leukoencephalopathy and immune reconstitution inflammatory syndrome (IRIS)

Progressive multifocal leukoencephalopathy is a viral encephalitis induced by the John Cunningham (JC) virus, an ubiquitous neurotropic papovavirus of the genus polyomavirus that in healthy people in latency resides in kidney and bone marrow cells. Activation and entry into the CNS were first seen in patients with malignancies of the hematopoietic system and an impaired immune system. During the 1980 and the 1990s with the appearance of human immunodeficiency virus infection in humans, PML was found to be the most important opportunistic infection of the central nervous system. As a result of highly efficient immunosuppressive and immunomodulatory treatments, in recent years, the number of PML cases again increased. PML is prevented by an intact cellular immune response and accordingly immune reconstitution can terminate established disease in the CNS. However, forced immune reconstitution can lead to massive destruction of virus-infected cells. This may result in clinical exacerbation associated with high morbidity and mortality and referred to as PML with immune reconstitution inflammatory syndrome (PML-IRIS). In the present review, we discuss virological properties and routes of infection in the CNS, but mostly focus on the pathology of PML and PML-IRIS and on the role of the immune system in these disorders. We show that PML and PML-IRIS result from predominant JC virus infection of oligodendrocytes and, to a lesser extent, of infected neurons. Inflammation in these encephalitides seems to be driven by a dominant cytotoxic T cell response which is massively exaggerated during IRIS.

Balancing Early Aggression Against Risk of Progression in Multiple Sclerosis

Multiple sclerosis is a chronic demyelinating disease characterized by focal and diffuse inflammation of the central nervous system resulting in significant physical and cognitive disabilities. Disease-modifying therapies targeting the dysfunctional immune response are most effective in the first few years after disease onset, indicating that there is a limited time window for therapy to influence the disease course. No evidence of disease activity is emerging as a new standard for treatment response and may be associated with improved long-term disability outcomes. An aggressive management strategy, including earlier use of more potent immunomodulatory agents and close monitoring of the clinical and radiologic response to treatment, is recommended to minimize early brain volume loss and slow the progression of physical and cognitive impairments in patients with relapsing-remitting multiple sclerosis.

Balancing the risks and benefits of biologic therapy in inflammatory bowel diseases

INTRODUCTION

The incidence of Inflammatory Bowel Diseases (IBD) is rising and overall epidemiology is changing. Goals of IBD therapy are also fast changing to reflect the concept of mucosal healing. IBD management is increasingly revolving around questions of ideal positioning of biologic therapies.

AREAS COVERED

This paper covers important concepts regarding two classes of biologic medications approved for treatment of IBD in the United States - anti-TNF-α agents and lymphocyte-homing antagonists. Topics covered include drug mechanism of action, pharmacokinetic considerations for the clinician including therapeutic drug monitoring, summary of current evidence of drug efficacy in IBD focusing on randomized, controlled trial data. Additionally, nuanced discussion of medication side-effects and adverse reactions is presented.

EXPERT OPINION

Paradigms of treatment goals in IBD are changing with increasing focus on mucosal healing. Concomitantly, our understanding of important factors that impact drug pharmacokinetic/pharmacodynamics relationships with biologic agents has increased which will help eventually develop personalized algorithms to optimize the efficacy of these agents. Though direct head-to-head comparisons between these agents are lacking, biologic agents can be considered the safest and most effective therapies introduced for IBD.

Anti-JC virus antibody titres increase over time with natalizumab treatment

Background:

Anti-JC virus antibody status is a risk factor for progressive multifocal leukoencephalopathy after natalizumab treatment in multiple sclerosis. Previous studies have used a cross-sectional approach to conclude that the presence and duration of natalizumab treatment does not influence anti-JCV Ab seropositivity.

Objectives:

Using a longitudinal approach, we measured change in anti-JCV Ab results after natalizumab treatment.

Methods:

Anti-JCV Ab results ( n = 1154) from the second-generation STRATIFY JCV™ DxSelect™ test were analysed from an observational cohort of MS patients on natalizumab ( n = 485; n = 340 with repeat testing; n = 657 repeat tests on natalizumab).

Results:

Across sequential paired tests, seroconversion rate was greater than seroreversion rate (40/364 (11.0%) versus 18/293 (6.1%); p < 0.05). Moreover, anti-JCV Ab index increased across longitudinal paired tests ( mA–B 0.102; paired t(656) = 5.0; p < 0.0001). This magnitude of Ab level increase far exceeds that expected due to increasing age alone.

Conclusion:

Our data suggest that natalizumab therapy is associated with a significant and substantial increase in anti-JCV Ab index over time. Further work should focus on the underlying mechanisms of this phenomenon, and the clinical relevance to risk stratification.

Neuroimaging of Natalizumab Complications in Multiple Sclerosis: PML and Other Associated Entities

Natalizumab (Tysabri) is a monoclonal antibody (α4 integrin antagonist) approved for treatment of multiple sclerosis, both for patients who fail therapy with other disease modifying agents and for patients with aggressive disease. Natalizumab is highly effective, resulting in significant decreases in rates of both relapse and disability accumulation, as well as marked decrease in MRI evidence of disease activity. As such, utilization of natalizumab is increasing, and the presentation of its associated complications is increasing accordingly. This review focuses on the clinical and neuroimaging features of the major complications associated with natalizumab therapy, focusing on the rare but devastating progressive multifocal leukoencephalopathy (PML). Associated entities including PML associated immune reconstitution inflammatory syndrome (PML-IRIS) and the emerging phenomenon of rebound of MS disease activity after natalizumab discontinuation are also discussed. Early recognition of neuroimaging features associated with these processes is critical in order to facilitate prompt diagnosis, treatment, and/or modification of therapies to improve patient outcomes.

Immune reconstitution inflammatory syndrome and natalizumab-Is it possible before removing the drug?

Multiple sclerosis (MS) patients treated with natalizumab have a significant reduction in annualized relapse rate; in these patients, a relapse is uncommon but not unexpected. In contrast, the appearance of a severe exacerbation is striking and requires the differential diagnosis with progressive multifocal leukoencephalopathy. Here, we describe a case of a 22-year-old woman with relapsing-remitting MS who developed an unexpected response after the patient׳s fifth natalizumab infusion with an aggressive radiological and clinical evolution. Changing the patient׳s treatment to fingolimod resulted in the absence of new clinical relapses and the absence of active lesions on brain magnetic resonance images (MRI) during the first 12 months of follow-up. We hypothesize that the appearance of natalizumab antibodies in this patient triggered lymphocyte migration to the central nervous system in a rebound phenomenon; this is similar to what occurs during immune reconstitution inflammatory syndrome (IRIS) after removal of natalizumab.

Combination therapy for the treatment of Crohn's disease

INTRODUCTION

Crohn's disease (CD) is an idiopathic inflammatory disorder of the gastrointestinal tract traditionally treated by the step-wise use of corticosteroids, antimetabolites and TNF-α antagonists. However, recent evidence indicates that the early introduction of drug combinations might be a superior strategy to step-care.

AREAS COVERED

In this article, we review existing literature regarding the efficacy and safety of combination drug therapy for the management of CD. Five major databases: MEDLINE, EMBASE, PubMed, the Cochrane Library (CENTRAL) and DDW abstracts were electronically searched from inception to February 2015 for any relevant studies.

EXPERT OPINION

Existing data strongly support the use of combination therapy for CD. The benefit of this approach appears to outweigh any associated risks. Until the role of gut selective therapies are better established, combination therapy should be considered the standard treatment approach for CD.

Immune reconstitution inflammatory syndrome associated with biologic therapy

The use of biologics in the treatment of autoimmune disease, cancer, and other immune conditions has revolutionized medical care in these areas. However, there are drawbacks to the use of these medications including increased susceptibility to opportunistic infections. One unforeseen risk once opportunistic infection has occurred with biologic use is the onset of immune reconstitution inflammatory syndrome (IRIS) upon drug withdrawal. Although originally described in human immunodeficiency virus (HIV) patients receiving highly active antiretroviral therapy, it has become clear that IRIS may occur when recovery of immune function follows opportunistic infection in the setting of previous immune compromise/suppression. In this review, we draw attention to this potential pitfall on the use of biologic drugs.

Emerging tumefactive multiple sclerosis after switching therapy from natalizumab to fingolimod

In this report we describe a multiple sclerosis patient who developed a relapse with magnetic resonance imaging (MRI) features of tumefactive demyelination after switching therapy from natalizumab to fingolimod. Tumefactive lesions emerged 16 weeks after stopping natalizumab and eight weeks after commencing fingolimod therapy but had been absent at the time of diagnosis and throughout the preceding course of the disease. Thus, the first-time occurrence of atypical lesion features may have been caused by the change in immunotherapy. The possible relevance of natalizumab withdrawal vs fingolimod introduction is discussed against the background of recently published case studies.

Progressive multifocal leukoencephalopathy: Dot-shaped inclusions and virus-host interactions

Progressive multifocal leukoencephalopathy (PML) is a fatal demyelinating disease caused by reactivation of the asymptomatic persistent pathogen human polyomavirus JC (JC virus). The pathology of affected brain tissues demonstrates oligodendroglia-like cells with viral inclusions in their enlarged nuclei, a diagnostic hallmark of this disease. Today, the pathological features of this disease are expanding, partly due to an unsteady balance between viral virulence and host immunity. Intranuclear viral inclusions were initially thought to be amphophilic materials comprising the entire enlarged nucleus, based on HE staining (full inclusions). Howevewr, recent immunohistochemical analyses detected the presence of intranuclear viral inclusions in dots (dot-shaped inclusions). The dot-shaped inclusions reflect clustered progeny virions at punctuated subnuclear domains called promyelocytic leukemia nuclear bodies, and are indicative of early-stage viral infection or suppressed viral proliferation. Second, the JC virus is usually reactivated in patients with impaired immunity, and therefore the inflammatory reactions are poor. However, the causes of immunosuppression are divergent, as seen with the frequent use of immunosuppressive drugs, including natalizumab. Therefore, the degree of host immunity is variable; some patients show marked anti-viral inflammatory reactions and a good prognosis, indicating that a strong resistance against viral infection remains. Recovery of the immune system may also induce paradoxical clinical worsening, known as immune reconstitution inflammatory syndrome, the mechanism of which has not been clarified. The virus-host interactions have increased in complexity, and the pathology of PML is diverging. In this review, the pathology of PML will be described, with a focus on the intranuclear target of JC virus infection and host inflammatory reactions.

VBP15, a novel anti-inflammatory, is effective at reducing the severity of murine experimental autoimmune encephalomyelitis

Multiple sclerosis is a chronic disease of the central nervous system characterized by an autoimmune inflammatory reaction that leads to axonal demyelination and tissue damage. Glucocorticoids, such as prednisolone, are effective in the treatment of multiple sclerosis in large part due to their ability to inhibit pro-inflammatory pathways (e.g., NFκB). However, despite their effectiveness, long-term treatment is limited by adverse side effects. VBP15 is a recently described compound synthesized based on the lazeroid steroidal backbone that shows activity in acute and chronic inflammatory conditions, yet displays a much-reduced side effect profile compared to traditional glucocorticoids. The purpose of this study was to determine the effectiveness of VBP15 in inhibiting inflammation and disease progression in experimental autoimmune encephalomyelitis (EAE), a widely used mouse model of multiple sclerosis. Our data show that VBP15 is effective at reducing both disease onset and severity. In parallel studies, we observed that VBP15 was able to inhibit the production of NFκB-regulated pro-inflammatory transcripts in human macrophages. Furthermore, treatment with prednisolone-but not VBP15-increased expression of genes associated with bone loss and muscle atrophy, suggesting lack of side effects of VBP15. These findings suggest that VBP15 may represent a potentially safer alternative to traditional glucocorticoids in the treatment of multiple sclerosis and other inflammatory diseases.