Progressive neurologic dysfunction in a psoriasis patient treated with dimethyl fumarate

High CD4+:CD8+ ratios with herpes zoster infections in patients with multiple sclerosis on dimethyl fumarate

BACKGROUND

Dimethyl fumarate (DMF) depletes CD8+ and CD4+ T cells, and cases of herpes zoster (HZ) in patients with multiple sclerosis (MS) on DMF have been documented.

OBJECTIVES

To evaluate lymphocyte subsets in patients with MS who developed HZ on DMF (Tecfidera) compared to matched controls who did not develop HZ.

METHODS

We used linear mixed-effects models to test for differences in white blood cell count, lymphocyte percentage, absolute lymphocyte count, CD3+ percentage, absolute CD3+ count, CD4+ percentage, absolute CD4+ count, CD8+ percentage, absolute CD8+ count, and CD4+:CD8+ ratio over time in HZ and non-HZ groups.

RESULTS

Eighteen patients developed HZ while on DMF. The linear mixed-effects model for CD4+:CD8+ ratio showed a significant difference between the HZ and non-HZ groups (p = 0.033). CD4+:CD8+ ratio decreased over time in the HZ group and increased over time in the non-HZ group.

CONCLUSION

Patients with MS who develop HZ while on DMF have high CD4+:CD8+ ratios, suggesting an imbalance of CD4+ and CD8+ cells that may put a patient at risk for developing HZ while on DMF. This result emphasizes the need for lymphocyte subset monitoring (including CD4+:CD8+ ratios) on DMF, as well as vaccination prior to DMF initiation.

Progressive multifocal leukoencephalopathy without overt immunosuppression

Progressive multifocal leukoencephalopathy (PML) is a central nervous system disease caused by the human polyomavirus 2 that usually occurs in a setting of immunodeficiency. PML without overt immunosuppression is considered a rare occurrence but has been described in multiple previous case reports and series. Its prevalence, overall frequency, and prognosis are largely unknown. This is a single-center retrospective review of all University of Florida cases with the ICD10 PML diagnosis code (A81.2). PML without overt immunosuppression was defined as absence of human immunodeficiency virus (HIV) infection, hematological malignancy, immunomodulatory/-suppressive medications, autoimmune conditions with a propensity for PML (sarcoidosis, systemic lupus erythematosus). Cases that did not fulfill criteria for clinically or histologically definite PML were excluded. Of 52 patients with the ICD10 code A 81.2, 17 fulfilled definite diagnostic criteria for PML. Overt immunosuppression was identified in 15/17 (88.2%) cases (10/17 (58.8%): human immunodeficiency virus; 5/17 (29.4%): immunomodulatory/-suppressive medication). Two/seventeen (11.8%) cases were consistent with PML without overt immunosuppression. Possible contributing factors were a preceding dog bite and mild hypogammaglobulinemia M (39 mg/dL) in case 1 and significant alcohol use without evidence for liver disease in case 2. Both cases were fatal within 6 (case 1) and 2 (case 2) months. The results suggest that PML without overt immunosuppression may be more common than previously described. Therefore, PML should be considered even in the absence of overt immunosuppression if clinical and radiographic findings are suggestive of the diagnosis.

A Case of Progressive Multifocal Leukoencephalopathy in a Fumaric Acid-Treated Psoriasis Patient With Severe Lymphopenia Among Other Risk Factors

Progressive multifocal leukoencephalopathy (PML) is a potentially fatal condition caused by a brain infection with JC polyomavirus (JCV), which occurs almost exclusively in immunocompromised patients. Modern immunosuppressive and immunomodulatory treatments for cancers and autoimmune diseases have been accompanied by increasing numbers of PML cases. We report a psoriasis patient treated with fumaric acid esters (FAEs) with concomitant hypopharyngeal carcinoma and chronic alcohol abuse who developed PML. Grade 4 lymphopenia at the time point of PML diagnosis suggested an immunocompromised state. This case underscores the importance of immune cell monitoring in patients treated with FAEs, even more so in the presence of additional risk factors for an immune dysfunction.

Clinical Significance of Helicobacter pylori Infection on Psoriasis Severity

The aim of the study was to appraise the link between psoriasis and Helicobacter pylori, investigate the influence of H. pylori treatment on psoriasis severity, determine the cutoff value of haptoglobin as a psoriatic biomarker, and determine the most reliable predictor for psoriasis in patients with H. pylori. This study was carried out on 100 adult Saudi participants from the Security Forces Hospital (Riyadh, Kingdom of Saudi Arabia). All participants were allocated into 5 groups (20/group): controls (G1), psoriatic patients (G2), patients with H. pylori (G3), psoriatic patients with untreated H. pylori (G4), and psoriatic patients with treated H. pylori (G5). The study was approved by the ethics committee of Security Forces Hospital, Riyadh, Saudi Arabia. The psoriasis area and severity index (PASI) score, ¹³C-urea breath test (¹³C-UBT), C-reactive protein (CRP), haptoglobin, platelet P-selectin, cluster of differentiation 4/cluster of differentiation 8 (CD4/CD8) ratio, and lymphocyte percentages were recorded. The haptoglobin level was significantly elevated in psoriatic patients compared with G1. In G5, there was significant attenuation in the PASI score, P-selectin, CRP, CD4/CD8 ratio, and lymphocyte percentage compared with G4. There was a significant positive correlation between psoriasis severity and ¹³C-UBT. In addition, ¹³C-UBT and PASI scores were significantly positively correlated with CRP, platelet P-selectin, and percentage of lymphocytes. H. pylori plays a potential role in psoriasis pathogenesis. H. pylori treatment attenuates psoriasis severity. Haptoglobin could be utilized as a psoriatic biomarker with 1.95 g/L as the cutoff value. The most reliable predictor for psoriasis in infected patients with H. pylori is ¹³C-UBT.

Risk factors for lymphopenia in patients with relapsing-remitting multiple sclerosis treated with dimethyl fumarate

OBJECTIVES

To identify risk factors for DMF-induced lymphopenia and characterize its impact on T lymphocyte subsets in MS patients.

METHODS

We performed a retrospective analysis of 194 RRMS patients treated with DMF at the Beth Israel Deaconess Medical Center (BIDMC) over a median of 17 months. We reviewed demographics, ethnic background, prior medication history, complete blood counts and T lymphocyte subsets. Possible lymphopenia risk factors examined included age, prior natalizumab exposure, vitamin D levels, and concomitant exposure to carbamazepine, opiates, tobacco, or steroids. Lymphopenia was defined as grade 1: absolute lymphocytes count (ALC) 800-999/μl; grade 2: ALC 500-799/μl; grade 3: ALC 200-499/μl; and grade 4: ALC < 200/μl.

RESULTS

Of 194 DMF-treated patients, 73 (38%) developed lymphopenia and reached an ALC nadir after a median of 504 days (range 82-932). Risk of developing DMF-induced lymphopenia increased with BMI 25-30, older age, white ethnicity, non-smoking status, and lowest quartile baseline ALC. Prior exposure to natalizumab or concomitant steroid, opiates or carbamazepine/oxcarbamazepine use was not associated with lymphopenia. Compared to baseline levels, CD8 T cells were significantly more reduced than CD4 cells. CD8 counts were more commonly reduced with age or white ethnicity. Subjects with BMI 25-30 was associated with a higher risk of abnormal CD4 cell count reductions. In contrast, non-smokers were more likely to experience reductions in both CD4 and CD8 counts while on DMF.

CONCLUSIONS

Patients with low baseline lymphocyte counts, with intermediate BMI, with white ethnicity, with advanced age, or with no tobacco use, had a significantly higher incidence of lymphopenia on DMF. Intermediate BMI or lowest quartile baseline ALC predicted low CD4 levels, while advanced age or white ethnicity predicted low CD8 levels from DMF exposure.

Risk factors for lymphopenia in patients with relapsing-remitting multiple sclerosis treated with dimethyl fumarate

OBJECTIVES

To identify risk factors for DMF-induced lymphopenia and characterize its impact on T lymphocyte subsets in MS patients.

METHODS

We performed a retrospective analysis of 194 RRMS patients treated with DMF at the Beth Israel Deaconess Medical Center (BIDMC) over a median of 17 months. We reviewed demographics, ethnic background, prior medication history, complete blood counts and T lymphocyte subsets. Possible lymphopenia risk factors examined included age, prior natalizumab exposure, vitamin D levels, and concomitant exposure to carbamazepine, opiates, tobacco, or steroids. Lymphopenia was defined as grade 1: absolute lymphocytes count (ALC) 800-999/μl; grade 2: ALC 500-799/μl; grade 3: ALC 200-499/μl; and grade 4: ALC < 200/μl.

RESULTS

Of 194 DMF-treated patients, 73 (38%) developed lymphopenia and reached an ALC nadir after a median of 504 days (range 82-932). Risk of developing DMF-induced lymphopenia increased with BMI 25-30, older age, white ethnicity, non-smoking status, and lowest quartile baseline ALC. Prior exposure to natalizumab or concomitant steroid, opiates or carbamazepine/oxcarbamazepine use was not associated with lymphopenia. Compared to baseline levels, CD8 T cells were significantly more reduced than CD4 cells. CD8 counts were more commonly reduced with age or white ethnicity. Subjects with BMI 25-30 was associated with a higher risk of abnormal CD4 cell count reductions. In contrast, non-smokers were more likely to experience reductions in both CD4 and CD8 counts while on DMF.

CONCLUSIONS

Patients with low baseline lymphocyte counts, with intermediate BMI, with white ethnicity, with advanced age, or with no tobacco use, had a significantly higher incidence of lymphopenia on DMF. Intermediate BMI or lowest quartile baseline ALC predicted low CD4 levels, while advanced age or white ethnicity predicted low CD8 levels from DMF exposure.

Central Nervous System Infections Complicating Immunosuppression and Transplantation

PURPOSE OF REVIEW

This article reviews infections associated with cancer treatments and immunosuppressive/immunomodulatory therapies used in both neoplastic and non-neoplastic conditions, including hematopoietic cell transplantation and solid organ transplantation. It provides a clinical approach to the most commonly affected patient groups based on clinicoanatomic presentation and disease-specific risks resulting from immune deficits and drugs received.

RECENT FINDINGS

The clinical presentations, associated neuroimaging findings, and CSF abnormalities of patients with central nervous system infections who are immunocompromised may differ from those of patients with central nervous system infections who are immunocompetent and may be confused with noninfectious processes. Triggering of brain autoimmunity with emergence of neurotropic antibodies has emerged as a recognized parainfectious complication. New unbiased metagenomic assays to identify obscure pathogens help clinicians navigate the increasing range of conditions affecting the growing population of patients with altered immunity.

SUMMARY

Despite evidence-based prophylactic regimens and organism-specific antimicrobials, central nervous system infections continue to cause significant morbidity and mortality in an increasing range of patients who are immunocompromised by their conditions and therapies. Multiple new drugs put patients at risk for progressive multifocal leukoencephalopathy, which has numerous imaging and clinical manifestations; patients at risk include those with multiple sclerosis, for whom infection risk is becoming one of the most important factors in therapeutic decision making. Efficient, early diagnosis is essential to improve outcomes in these often-devastating diseases.

Fumaric acid ester-induced T-cell lymphopenia in the real-life treatment of psoriasis

BACKGROUND

Fumaric acid esters (FAEs) are used to treat psoriasis and are known to cause lymphopenia in roughly 60% of the patients. Much remains to be elucidated about the biological effects of FAEs on lymphocytes.

OBJECTIVE

To evaluate the influence of long-term FAE (Fumaderm® ) treatment on peripheral blood CD4+ and CD8+ T cells, CD19+ B cells and CD56+ natural killer (NK) cells in psoriasis.

METHODS

In this single-centre retrospective observational subcohort study, we obtained leucocyte and lymphocyte subset counts before initiating FAE therapy in 371 psoriasis patients (mean age, 47.8 years; 63.3% males) and monitored them during treatment (mean treatment duration, 2.9 years). Multiparametric flow cytometry was used for immunophenotyping.

RESULTS

FAEs significantly reduced the numbers of CD4+ T, CD8+ T, CD19+ B and CD56+ NK cells. Among lymphocyte subsets, the mean percentage reduction from baseline was always highest for CD8+ T cells, with a peak of 55.7% after 2 years of therapy. The risk of T-cell lymphopenia increased significantly with the age of the psoriasis patients at the time that FAE therapy was initiated. It was significantly decreased for the combination therapy with methotrexate and folic acid (vitamin B9) supplementation. Supporting evidence was found suggesting that T-cell lymphopenia enhances the effectiveness of FAE therapy.

CONCLUSIONS

Monitoring distinct T-cell subsets rather than just absolute lymphocyte counts may provide more meaningful insights into both the FAE treatment safety and efficacy. We therefore suggest optimizing pharmacovigilance by additionally monitoring CD4+ and CD8+ T-cell counts at regular intervals, especially in patients of middle to older age. Thus, further prospective studies are needed to establish evidence-based recommendations to guide dermatologists in the management of psoriasis patients who are taking FAEs and who develop low absolute T-cell counts.

The spectrum of progressive multifocal leukoencephalopathy: a practical approach

John Cunningham virus (JCV) infection of the central nervous system causes progressive multifocal leukoencephalopathy (PML) in patients with systemic immunosuppression. With the increased application of modern immunotherapy and biologics in various immune-mediated disorders, the PML risk spectrum has changed. Thus, new tools and strategies for risk assessment and stratification in drug-associated PML such as the JCV antibody indices have been introduced. Imaging studies have highlighted atypical presentations of cerebral JCV disease such as granule cell neuronopathy. Imaging markers have been developed to differentiate PML from new multiple sclerosis lesions and to facilitate the early identification of pre-clinical manifestations of PML and its immune reconstitution inflammatory syndrome. PML can be diagnosed either by brain biopsy or by clinical, radiographic and virological criteria. Experimental treatment options including immunization and modulation of interleukin-mediated immune response are emerging. PML should be considered in any patient with compromised systemic or central nervous system immune surveillance presenting with progressive neurological symptoms.

Oral Therapies for Multiple Sclerosis

Multiple sclerosis treatment faces tremendous changes owing to the approval of new medications, some of which are available as oral formulations. Until now, the four orally available medications, fingolimod, dimethylfumarate (BG-12), teriflunomide, and cladribine have received market authorization, whereas laquinimod is still under development. Fingolimod is a sphingosine-1-phosphate inhibitor, which is typically used as escalation therapy and leads to up to 60% reduction of the annualized relapse rate, but might also have neuroprotective properties. In addition, there are three more specific S1P agonists in late stages of development: siponimod, ponesimod, and ozanimod. Dimethylfumarate has immunomodulatory and cytoprotective functions and is used as baseline therapy. Teriflunomide, the active metabolite of the rheumatoid arthritis medication leflunomide, targets the dihydroorotate dehydrogenase, thus inhibiting the proliferation of lymphocytes by depletion of pyrimidines. Here we will review the mechanisms of action, clinical trial data, as well as data about safety and tolerability of the compounds.

A Punctate Magnetic Resonance Imaging Pattern in a Patient with Systemic Lupus Erythematosus Is an Early Sign of Progressive Multifocal Leukoencephalopathy: A Clinicopathological Study

A 37-year-old woman with systemic lupus erythematosus presented with gait disturbance and cognitive dysfunction. Brain magnetic resonance imaging (MRI) revealed small, punctate, T2-/fluid-attenuated inversion recovery-hyperintense and T1-hypointense lesions without gadolinium enhancement, which is atypical for progressive multifocal leukoencephalopathy (PML). On a pathological examination of biopsied brain tissues, JC virus-infected cells were hardly detected via immunohistochemistry but were certainly detected via in situ hybridization, conclusively verifying the PML diagnosis. After tapering off the immunosuppressant and mefloquine administration, the MRI findings revealed gradual improvement, and she has been stable for over 18 months. A punctate MRI pattern is not specific to natalizumab-associated PML but may be a ubiquitous early sign useful for the early diagnosis of PML.

Demyelination during anti-tumour necrosis factor therapy for psoriasis

Anti-tumour necrosis factor (anti-TNF) therapies have been associated with neurological complications, including in rare cases demyelinating disease. It is currently unknown whether patients who have received more than one immunosuppressive agent or anti-TNF have a greater risk of demyelination. We report the case of a 37-year-old woman with psoriasis who presented with an acute episode of demyelination while on anti-TNF therapy. This case was complicated by the fact that progressive multifocal leukoencephalopathy was considered the likely diagnosis initially and was only definitively excluded by brain biopsy. This case demonstrates the difficulty establishing the correct diagnosis in patients with atypical presentations on immunomodulating therapies. We present this rare case of demyelination in a patient who received multiple immunosuppressive therapies to highlight this challenging clinical situation and discuss management with a literature review.

T cell deficiencies as a common risk factor for drug associated progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a disease of the central nervous system caused by neuropathogenic prototypes of ubiquitous community-acquired JC virus (JCV). The disease became of particular concern following its association with certain therapies that modulate immune system function without heavy immunosuppression. Due to lack of prophylactic/treatment options and poor outcomes, which often include severe disability or death, PML is a considerable concern for development of new drugs that interfere with immune system functions. In this review of clinical and research findings, we discuss the evidence that deficiencies in CD4⁺ T helper cells, cytotoxic CD8⁺ T cells, and interferon gamma are of crucial importance for development of PML under a variety of circumstances, including those associated with use of various drugs, regardless of differences in their mechanisms of action. These deficiencies apparently enable transformation of the harmless JCV archetype into neuropathogenic prototypes, but the site(s), and the mechanisms, of this transformation are yet to be elucidated. Here we discuss the evidence for brain as one of the sites of this transformation, and propose a model of PML pathogenesis that emphasizes the central role of T cell deficiencies in the two life cycles of the JCV, one non-pathogenic and one neuropathogenic. Finally, we conclude that the development of clinical grade T cell functional tests and more consistent use of already available laboratory tests for T cell subset analysis would greatly aid the effort to more accurately predict and assess the magnitude of PML risk for concerned therapeutic interventions.

Steering through complexity: management approaches in multiple sclerosis

PURPOSE OF REVIEW

This review evaluates current and late-phase developing therapies for multiple sclerosis in regard to therapeutic efficacy and patient safety in light of recent published and presented observations from 2015.

RECENT FINDINGS

We describe data that provide supportive evidence for comparisons of therapeutic efficacy of multiple sclerosis therapies and review available data on rare but serious adverse events associated with these therapies.

SUMMARY

Serious adverse events that are sometimes rare and unpredictable may substantially alter current approaches to multiple sclerosis treatments. New therapies that have proved superior effects compared with older therapies will also impact multiple sclerosis treatment practice in the near future.

Remitting long-standing major depression in a multiple sclerosis patient with several concurrent conditions

In this report, we discuss the case of an multiple sclerosis (MS) patient, age 62, who learned to attain and sustain euthymia despite his ailments. He has Ehlers Danlos Syndrome (EDS), asthma, MS, urticaria, and major depression (MD). Despite thriving limitations, the patient is an accomplished scientist, who struggled for > twelve years to emerge from being confined to bed and wheel chair with MS, to walking with crutches, scuba diving, writing manuscripts, and living a positive life. Through former educators, he reacquired problem-solving habits to study the literature on his illnesses; keep records; try new therapies; and use pharmaceutical, nutritional, physical, and psychological methods to attain euthymia. With this inculcation, years later, he discovered that dimethyl fumarate (DMF) suppressed inflammation, cramping, urticaria, and asthma; and the combination of bupropion, S-adenosylmethionine (SAMe), vitamin-D3 (vit-D3), yoga, and self-hypnosis relieved MD. Then, after a 14-month respite, the patient, discovered that he had adult onset craniopharyngioma: a benign, recurring, epithelial tumor that grows from vestigial embryonic tissue (Rathke's pouch) which formed the anterior pituitary. The tumor grows aggressively and causes surrounding tissue and function losses. It caused headaches, disorientation, bitemporal vision loss, among other problems. To emerge from this conundrum, the patient employed his relearned habits; the above antidepressant cocktail (bupropion, SAMe, and vit-D3); and with 30 fractionated stereotactic radiation treatments shrank his tumor and gained relief. This is a single case, and methods we discovered serendipitously may not work for other chronically ill patients. Consequently, we want to encourage such patients and their physicians to discuss their experiences in peer-reviewed domains so readers may acquire new perspectives that help individualize their care, and have productive contented lives.

Predictors of hematological abnormalities in multiple sclerosis patients treated with fingolimod and dimethyl fumarate and impact of treatment switch on lymphocyte and leukocyte count

BACKGROUND

There is limited data regarding the predictors of hematological abnormalities in multiple sclerosis (MS) patients treated with dimethyl fumarate (DMF) or fingolimod (FNG), and the impact of treatment switch on lymphocyte and leukocyte count METHODS: We identified 405 patients on DMF and 300 patients on FNG (treatment duration: at least 12 month) within a large prospective study of MS patients conducted at the Partners MS Center, Brigham and Women's Hospital (CLIMB study) between Jan 2011 to Feb 2016. Patients had complete blood counts with differentials at baseline and every 6 months while on treatment. Most participants had a clinical visit with complete neurologic examinations every 6 months and brain MRI scan every 12 months. T cell subset profile was available for subgroup of patients (n = 116).

RESULTS

In the FNG group, the risk of developing lymphopenia grade 4 (< 200) was higher in female patients (p = 0.0117) and those who were previously treated with natalizumab (p = 0.0116), while the risk of lymphopenia grade 3b+4 (< 350) was higher in female patients (p = 0.0009). DMF treated patients with lower baseline lymphocyte count had a higher chance of developing lymphopenia grade 2 (< 800) (p < 0.0001) or 2+3 (< 500) (p < 0.0001). We examined the effect of treatment switch between DMF and FNG. No significant recovery in lymphocyte and leukocyte count was observed after treatment switches. Reduced dosing of FNG in patients with lymphopenia led to increase in lymphocyte count but also increased disease activity in 25% of patients.

CONCLUSION

Female sex and prior exposure to natalizumab increased the probability of lymphopenia on FNG, while low absolute lymphocyte count was associated with increased risk of lymphopenia on DMF. Parallel switch did not lead to recovery from hematological abnormalities. Long-term studies with larger number of patients are required to confirm our findings and to establish guidelines for prediction and management of hematological abnormalities.

Progressive multi-focal leucoencephalopathy - driven from rarity to clinical mainstream by iatrogenic immunodeficiency

Advances in immune-mediated targeted therapies have proved to be a double-edged sword for patients by highlighting the risk of iatrogenic infective complications. This has been exemplified by progressive multi-focal leucoencephalopathy (PML), a hitherto rare devastating viral infection of the brain caused by the neurotrophic JC polyoma virus. While PML achieved prominence during the first two decades of the HIV epidemic, effective anti-retroviral treatment and restitution of T cell function has led to PML being less prominent in this population. HIV infection as a predisposing factor has now been supplanted by T cell immunodeficiency induced by a range of immune-mediated therapies as a major cause of PML. This review focuses on PML in the context of therapeutic immunosuppression and encompasses therapeutic monoclonal antibodies, novel immunomodulatory agents such as Fingolimod and dimethyl fumarate, as well as emerging data on PML in primary immune deficiency.

Progressive multifocal leukoencephalopathy in patients treated with fumaric acid esters: a review of 19 cases

Progressive multifocal leukoencephalopathy (PML) is a rare and potentially fatal condition caused by a brain infection with JC polyomavirus (JCV). PML develops almost exclusively in immunocompromised patients and has recently been associated with use of fumaric acid esters (FAEs), or fumarates. We reviewed the literature and the Dutch and European pharmacovigilance databases in order to identify all available FAE-associated PML cases and distinguish possible common features among these patients. A total of 19 PML cases associated with FAE use were identified. Five cases were associated with FAE use for multiple sclerosis and 14 for psoriasis. Ten patients were male and nine were female. The median age at PML diagnosis was 59 years. The median duration of FAE therapy to PML symptom onset or appearance of first PML lesion on brain imaging was 31 months (range 6-110). In all cases a certain degree of lymphocytopenia was reported. The median duration of lymphocytopenia to PML symptom onset was 23 months (range 6-72). The median lymphocyte count at PML diagnosis was 414 cells/µL. CD4 and CD8 counts were reported in ten cases, with median cell count of 137 and 39 cells/µL, respectively. Three patients died (16% mortality). The association between occurrence of PML in patients with low CD4 and CD8 counts is reminiscent of PML cases in the HIV population and suggests that loss of T cells is the most important risk factor.

Multiple sclerosis update: use of MRI for early diagnosis, disease monitoring and assessment of treatment related complications

MRI has long been established as the most sensitive in vivo technique for detecting multiple sclerosis (MS) lesions. The 2010 revisions of the McDonald Criteria have simplified imaging criteria, such that a diagnosis of MS can be made on a single contrast-enhanced MRI scan in the appropriate clinical context. New disease-modifying therapies have proven effective in reducing relapse rate and severity. Several of these therapies, most particularly natalizumab, but also dimethyl fumarate and fingolimod, have been associated with progressive multifocal leukoencephalopathy (PML). PML-immune reconstitution inflammatory syndrome (IRIS) has been recognized in patients following cessation of natalizumab owing to PML, and discontinuation for other reasons can lead to the phenomenon of rebound MS. These complications often provide a diagnostic dilemma and have implications for imaging surveillance of patients. We demonstrate how the updated McDonald Criteria aid the diagnosis of MS and describe the imaging characteristics of conditions such as PML and PML-IRIS in the context of MS. Potential imaging surveillance protocols are considered for the diagnosis and assessment of complications. We will explain how changes in MS treatment are leading to new imaging demands in order to monitor patients for disease progression and treatment-related complications.

Dimethyl Fumarate Selectively Reduces Memory T Cells and Shifts the Balance between Th1/Th17 and Th2 in Multiple Sclerosis Patients

Dimethyl fumarate (DMF; trade name Tecfidera) is an oral formulation of the fumaric acid ester that is Food and Drug Administration approved for treatment of relapsing-remitting multiple sclerosis. To better understand the therapeutic effects of Tecfidera and its rare side effect of progressive multifocal leukoencephalopathy, we conducted cross-sectional and longitudinal studies by immunophenotyping cells from peripheral blood (particularly T lymphocytes) derived from untreated and 4-6 and 18-26 mo Tecfidera-treated stable relapsing-remitting multiple sclerosis patients using multiparametric flow cytometry. The absolute numbers of CD4 and CD8 T cells were significantly decreased and the CD4/CD8 ratio was increased with DMF treatment. The proportions of both effector memory T cells and central memory T cells were reduced, whereas naive T cells increased in treated patients. T cell activation was reduced with DMF treatment, especially among effector memory T cells and effector memory RA T cells. Th subsets Th1 (CXCR3⁺), Th17 (CCR6⁺), and particularly those expressing both CXCR3 and CD161 were reduced most significantly, whereas the anti-inflammatory Th2 subset (CCR3⁺) was increased after DMF treatment. A corresponding increase in IL-4 and decrease in IFN-γ and IL-17-expressing CD4⁺ T cells were observed in DMF-treated patients. DMF in vitro treatment also led to increased T cell apoptosis and decreased activation, proliferation, reactive oxygen species, and CCR7 expression. Our results suggest that DMF acts on specific memory and effector T cell subsets by limiting their survival, proliferation, activation, and cytokine production. Monitoring these subsets could help to evaluate the efficacy and safety of DMF treatment.

[Monitoring of blood parameters under course-modified MS therapy : Substance-specific relevance and current recommendations for action]

With the approval of various substances for the immunotherapy of multiple sclerosis (MS), treatment possibilities have improved significantly over the last few years. Indeed, the choice of individually tailored preparations and treatment monitoring for the treating doctor is becoming increasingly more complex. This is particularly applicable for monitoring for a treatment-induced compromise of the immune system. The following article by members of the German Multiple Sclerosis Skills Network (KKNMS) and the task force "Provision Structures and Therapeutics" summarizes the practical recommendations for approved immunotherapy for mild to moderate and for (highly) active courses of MS. The focus is on elucidating the substance-specific relevance of particular laboratory parameters with regard to the mechanism of action and the side effects profile. To enable appropriate action to be taken in clinical practice, any blood work changes that can be expected, in addition to any undesirable laboratory findings and their causes and relevance, should be elucidated.

Progressive Multifocal Leukoencephalopathy in HIV-Uninfected Individuals

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system (CNS) caused by the human neurotropic polyomavirus JC (JCV). The disease occurs virtually exclusively in immunocompromised individuals, and, prior to the introduction of antiretroviral therapy, was seen most commonly in the setting of HIV/AIDS. More recently, however, the incidence of PML in HIV-uninfected persons has increased with broader use of immunosuppressive and immunomodulatory medications utilized in a variety of systemic and neurologic autoimmune disorders. In this review, we discuss the epidemiology and clinical characteristics of PML in HIV-uninfected individuals, as well as diagnostic modalities and the limited treatment options. Moreover, we describe recent findings regarding the neuropathogenesis of PML, with specific focus on the unique association between PML and natalizumab, a monoclonal antibody that prevents trafficking of activated leukocytes into the CNS that is used for the treatment of multiple sclerosis.

Predictors and characteristics of seizures in survivors of progressive multifocal leukoencephalopathy

This study aims to determine the risk factors for epileptogenesis and characteristics of seizures in patients with progressive multifocal leukoencephalopathy (PML) who survive more than 1 year from onset of neurological symptoms (PML survivors). We reviewed clinical data including seizure history and MR imaging studies from PML survivors evaluated at our institution between 1997 and 2014. PML progressors who passed away within 1 year and patients with a history of seizures prior to PML diagnosis were excluded from the analysis. Of 64 PML survivors, 28 (44 %) developed seizures. The median time from the onset of PML symptoms to the first seizure was 5.4 months (range 0-159) and 64 % of patients with seizures had them within the first year. The presence of juxtacortical PML lesions was associated with a relative risk of seizures of 3.5 (p < 0.02; 95 % confidence interval (CI) 1.3-9.4) in multivariate analyses. Of all seizure types, 86 % were focal and 60 % most likely originated from the frontal lobes. Among seizure patients, 89 % required treatment, including one (54 %), two (25 %), or three (10.5 %) antiepileptic drugs. Seizures are a frequent complication in PML and can develop throughout the entire course of the disease. However, late onset seizures did not signify PML relapse. Seizures may require treatment with multiple antiepileptic medications and are a significant co-morbidity in PML.

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.

Relapse frequency in transitioning from natalizumab to dimethyl fumarate: assessment of risk factors

Risk of relapse after natalizumab (NAT) cessation and switch to dimethyl fumarate (DMF) is unknown. The objective of this paper is to identify the risk and associated risk factors for relapse after switching from NAT to DMF in relapsing-remitting multiple sclerosis. Patients (n = 30) were treated with NAT for ≥12 months and then switched to DMF in a mean of 50 days. Patient age, annualized relapse rates (ARR), Expanded Disability Status Scale scores (EDSS), and lymphocyte counts were assessed. Overall, eight patients (27 %) had relapses after switching to DMF. Five patients (17 %) suffered severe relapses with multifocal clinical and radiological findings. New lesions by MRI (T2 hyperintense or enhancing) were observed in 35 % of patients. Relapses occurred at a mean of 3.5 months after NAT cessation. Patient age and elevated ARR prior to NAT use were significantly associated with risk of relapse after switch to DMF. Once on DMF for 4 months prior to relapse, lymphocyte count decreased more significantly in patients without relapses than those with relapses. Switching from NAT to DMF correlated with increased relapses. Young patient age, high ARR and stability of lymphocyte counts were risk factors for relapse after transition from NAT to DMF.

Diagnostic delay in progressive multifocal leukoencephalopathy

We investigated delay in diagnosing progressive multifocal leukoencephalopathy (PML). The median time from initial symptom to diagnosis was 74 days (range 1–1643) in 111 PML patients seen at our institution from 1993 to 2015. Another diagnosis was considered before PML in nearly two–thirds, and more than three–quarters of patients suffered from diagnostic delay greater than 1 month, irrespective of their underlying immunosuppressive condition. Extended diagnostic delay occurred more frequently in patients with possible PML, and among HIV⁺ patients with higher CD4⁺ T‐cell counts at symptom onset. Prompt diagnosis may improve survival of PML in so far as immune reconstitution can be effected, and prevent unnecessary interventions.

Disease-modifying therapies and infectious risks in multiple sclerosis

Immunomodulatory and immunosuppressive treatments for multiple sclerosis (MS) are associated with an increased risk of infection, which makes treatment of this condition challenging in daily clinical practice. Use of the expanding range of available drugs to treat MS requires extensive knowledge of treatment-associated infections, risk-minimizing strategies and approaches to monitoring and treatment of such adverse events. An interdisciplinary approach to evaluate the infectious events associated with available MS treatments has become increasingly relevant. In addition, individual stratification of treatment-related infectious risks is necessary when choosing therapies for patients with MS, as well as during and after therapy. Determination of the individual risk of infection following serial administration of different immunotherapies is also crucial. Here, we review the modes of action of the available MS drugs, and relate this information to the current knowledge of drug-specific infectious risks and risk-minimizing strategies.

Dimethyl fumarate treatment of relapsing-remitting multiple sclerosis influences B-cell subsets

Objective:

To test the hypothesis that dimethyl fumarate (Tecfidera, BG-12) affects B-cell subsets in patients with relapsing-remitting multiple sclerosis (RRMS).

Methods:

Peripheral blood B cells were compared for surface marker expression in patients with RRMS prior to initiation of treatment, after 4–6 months, and at more than 1 year of treatment with BG-12. Production of interleukin (IL)–10 by RRMS patient B cells was also analyzed.

Results:

Total numbers of peripheral blood B lymphocytes declined after 4–6 months of BG-12 treatment, due to losses in both the CD27+ memory B cells and CD27^neg B-cell subsets. Some interpatient variability was observed. In contrast, circulating CD24^highCD38^high (T2-MZP) B cells increased in percentage in the majority of patients with RRMS after 4–6 months and were present in higher numbers in all of the patients after 12 months of treatment. The CD43+CD27+ B-1 B cells also increased at the later time point in most patients but were unchanged at 4–6 months compared to pretreatment levels. Purified B cells from 7 of the 9 patients with RRMS tested after 4–6 months of treatment were able to produce IL-10 following CD40 ligand stimulation, and the amount corresponded with the combined levels of T2-MZP and B-1 B cells in the sample. None of the patients with RRMS in this study have had a relapse while taking BG-12.

Conclusions:

These data suggest that BG-12 differentially affects B-cell subsets in patients with RRMS, resulting in increased numbers of circulating B lymphocytes with regulatory capacity.

Monoclonal antibody therapies for the treatment of relapsing-remitting multiple sclerosis: differentiating mechanisms and clinical outcomes

Monoclonal antibody (mAb) therapies for relapsing-remitting multiple sclerosis (MS) target immune cells or other molecules involved in pathogenic pathways with extraordinary specificity. Natalizumab and alemtuzumab are the only two currently approved mAbs for the treatment of MS, having demonstrated significant reduction in clinical and magnetic resonance imaging disease activity and disability in clinical studies. Ocrelizumab and daclizumab are in the late stages of phase III trials, and several other mAbs are in the early stages of clinical evaluation. mAbs have distinct structural characteristics (e.g. chimeric, humanized, fully human) and unique targets (e.g. blocking interactions, induction of signal transduction by receptor binding, complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity) conferring different mechanisms of action in MS. Because of these differences, mAbs for MS do not constitute a single treatment class; each must be considered individually when selecting appropriate therapy. Furthermore, in reviewing the data from clinical studies of mAbs, attention should be drawn to use of different comparators (e.g. placebo or interferon β-1a) and study designs. Each mAb treatment has a unique administration schedule. In the decision to select the appropriate treatment for each individual MS patient, careful review of the benefits relative to risks of mAbs is balanced against the risk of development of MS-associated disability.