The emergence of progressive multifocal leukoencephalopathy (PML) in rheumatic diseases

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Use of Rituximab in Childhood Idiopathic Nephrotic Syndrome

Rituximab is an established therapy in children with idiopathic nephrotic syndrome to sustain short- to medium-term disease remission and avoid steroid toxicities. Recent trials focus on its use as a first-line agent among those with milder disease severity. Rituximab is used in multidrug refractory nephrotic syndrome and post-transplant disease recurrence, although the evidence is much less substantial. Available data suggest that the treatment response to rituximab depends on various patient factors, dosing regimen, and the concomitant use of maintenance immunosuppression. After repeated treatments, patients are found to have an improving response overall with a longer relapse-free period. The drug effect, however, is not permanent, and 80% of patients eventually relapse and many will require an additional course of rituximab. This underpins the importance of understanding the long-term safety profile on repeated treatments. Although rituximab appears to be generally safe, there are concerns about long-term hypogammaglobulinemia, especially in young children. Reliable immunophenotyping and biomarkers are yet to be discovered to predict treatment success, risk of both rare and severe side effects, e.g. , persistent hypogammaglobulinemia, and guiding of redosing strategy. In this review, we highlight recent advances in the use of rituximab for childhood nephrotic syndrome and how the therapeutic landscape is evolving.

Long-Term Efficacy and Safety of Repeated Rituximab to Maintain Remission in Idiopathic Childhood Nephrotic Syndrome: An International Study

BACKGROUND

Long-term outcomes after multiple courses of rituximab among children with frequently relapsing, steroid-dependent nephrotic syndrome (FRSDNS) are unknown.

METHODS

A retrospective cohort study at 16 pediatric nephrology centers from ten countries in Asia, Europe, and North America included children with FRSDNS who received two or more courses of rituximab. Primary outcomes were relapse-free survival and adverse events.

RESULTS

A total of 346 children (age, 9.8 years; IQR, 6.6-13.5 years; 73% boys) received 1149 courses of rituximab. A total of 145, 83, 50, 28, 22, and 18 children received two, three, four, five, six, and seven or more courses, respectively. Median (IQR) follow-up was 5.9 (4.3-7.7) years. Relapse-free survival differed by treatment courses (clustered log-rank test P<0.001). Compared with the first course (10.0 months; 95% CI, 9.0 to 10.7 months), relapse-free period and relapse risk progressively improved after subsequent courses (12.0-16.0 months; HRadj, 0.03-0.13; 95% CI, 0.01 to 0.18; P<0.001). The duration of B-cell depletion remained similar with repeated treatments (6.1 months; 95% CI, 6.0 to 6.3 months). Adverse events were mostly mild; the most common adverse events were hypogammaglobulinemia (50.9%), infection (4.5%), and neutropenia (3.7%). Side effects did not increase with more treatment courses nor a higher cumulative dose. Only 78 of the 353 episodes of hypogammaglobulinemia were clinically significant. Younger age at presentation (2.8 versus 3.3 years; P=0.05), age at first rituximab treatment (8.0 versus 10.0 years; P=0.01), and history of steroid resistance (28% versus 18%; P=0.01) were associated with significant hypogammaglobulinemia. All 53 infective episodes resolved, except for one patient with hepatitis B infection and another with EBV infection. There were 42 episodes of neutropenia, associated with history of steroid resistance (30% versus 20%; P=0.04). Upon last follow-up, 332 children (96%) had normal kidney function.

CONCLUSIONS

Children receiving repeated courses of rituximab for FRSDNS experience an improving clinical response. Side effects appear acceptable, but significant complications can occur. These findings support repeated rituximab use in FRSDNS.

Single-Center Experience on Progressive Multifocal Leukoencephalopathy (PML) cases, neuroimaging relevance, and management at West Virginia University (WVU)

Progressive Multifocal Leukoencephalopathy (PML) is an increasingly common and rapidly fatal demyelinating infection of CNS caused by the highly prevalent JCV in immunocompromised individuals belonging to all age groups and genders. HIV is the most common predisposing factor among other immunodeficient conditions leading to reactivation and multiple neurological symptoms. It has varied findings on MRI and diagnosis is confirmed by positive JC virus in CSF. We report 12 confirmed cases of PML from a single academic center. We comprehensively described clinical presentations, risk factors, CSF and neuroimaging findings, treatment and outcome for these cases of PML, a rare disease. The cases were almost equivalently distributed among young and old age groups and both genders. Positive JC virus on CSF was present in the majority of cases along with mild to severe reduction in lymphocyte counts. Significant MRI changes were present in all cases ranging from T2 hypertense signals to white matter lesions in various regions. Treatment with the reversion of immune-modulators, optimization of antiviral therapy (ART), plasmapheresis (PLEX), IVIG, Mirtazapine, oral steroids, and others was started as soon as the diagnosis was made in the majority of the cases. However, PML is a rapidly fatal illness and hence, survival was only seen in 4 cases in our study. The objective of this article is to highlight the importance of early diagnosis of PML with CSF findings and neuroimaging, early reversion of immunosuppressive medications, and careful monitoring and treatment of HIV cases with goals to reduce mortality, long-term morbidity, and deficits. This article is protected by copyright. All rights reserved.

Successful treatment of refractory chronic bullous disease of childhood with rituximab

Chronic bullous disease of childhood is a rare subepidermal bullous disease with a hallmark of linear IgA deposition along basement membrane zone seen on direct immunofluorescence. We report a case of a 2-year-old male child, who had recurrent and multiple bullous eruptions over body and he was not responding to conventional therapy. He had earlier developed a drug reaction to dapsone which is considered the drug of choice for this condition. We report successful management of this case with injection rituximab which is a chimeric monoclonal antibody against CD20, which is primarily found on the surface of B cells.

Rituximab in children with steroid sensitive nephrotic syndrome: in quest of the optimal regimen

Rituximab has emerged as an effective and important therapy in children with complicated frequently relapsing and steroid-dependent nephrotic syndrome to induce long-term disease remission and avoid steroid toxicities. The optimal rituximab regimen is not totally well defined, and there are many varying practices worldwide. We will in this review describe how patient factors, rituximab dose, and use of maintenance immunosuppression affect treatment outcomes. Specifically, low-dose rituximab without concomitant immunosuppression is associated with shorter relapse-free duration while other regimens have comparable outcomes. Patients with more severe disease generally have worse response to rituximab. Although rituximab appears to be generally safe, there are growing concerns of chronic hypogammaglobulinemia and impaired immunity especially in young children. Reliable prognostications and biomarkers for guiding subsequent treatments to avoid excessive treatments are yet to be identified. In this review, we will outline the, as we see it, best approach of rituximab in childhood steroid sensitive nephrotic syndrome at the present state of knowledge.

Prophylactic rituximab administration in children with complicated nephrotic syndrome

BACKGROUND

Rituximab is effective for maintaining remission in patients with complicated nephrotic syndrome, although a history of steroid-resistant nephrotic syndrome (SRNS) is a risk factor for early relapse. We investigated the efficacy of prophylactic rituximab treatment for maintaining remission after B cell recovery.

METHODS

Patients with complicated steroid-dependent or frequently relapsing nephrotic syndrome with history of SRNS who received a single dose of rituximab (375 mg/m²) and continued immunosuppressive agents were enrolled in this retrospective study. Patients were divided into two groups: a prophylaxis group, which received additional rituximab treatment at B cell recovery and a non-prophylaxis group. The relapse-free period from the last rituximab infusion (the second treatment in prophylaxis group and the first treatment in non-prophylaxis group) was compared between two groups using the Kaplan-Meier method, and risk factors for early relapse were calculated using multivariate analysis by Cox proportional hazards model.

RESULTS

Sixteen patients in the prophylaxis group and 45 in the non-prophylaxis group were enrolled. Fifty-percent relapse-free survival after the last rituximab treatment was 667 days in the former and 335 days in the latter (p = 0.001). Multivariate analysis showed that additional rituximab treatment was the only significant negative factor for early relapse, with a hazard ratio of 0.40 (p = 0.02). Fifty-percent relapse-free survival after B cell recovery was much longer in the prophylaxis group (954 vs. 205.5 days, p = 0.003).

CONCLUSIONS

Additional rituximab treatment at B cell recovery can maintain prolonged remission even after B cell recovery in patients with complicated nephrotic syndrome with history of SRNS.

Progressive multifocal leukoencephalopathy and the spectrum of JC virus-related disease

Progressive multifocal leukoencephalopathy (PML) is a devastating CNS infection caused by JC virus (JCV), a polyomavirus that commonly establishes persistent, asymptomatic infection in the general population. Emerging evidence that PML can be ameliorated with novel immunotherapeutic approaches calls for reassessment of PML pathophysiology and clinical course. PML results from JCV reactivation in the setting of impaired cellular immunity, and no antiviral therapies are available, so survival depends on reversal of the underlying immunosuppression. Antiretroviral therapies greatly reduce the risk of HIV-related PML, but many modern treatments for cancers, organ transplantation and chronic inflammatory disease cause immunosuppression that can be difficult to reverse. These treatments — most notably natalizumab for multiple sclerosis — have led to a surge of iatrogenic PML. The spectrum of presentations of JCV-related disease has evolved over time and may challenge current diagnostic criteria. Immunotherapeutic interventions, such as use of checkpoint inhibitors and adoptive T cell transfer, have shown promise but caution is needed in the management of immune reconstitution inflammatory syndrome, an exuberant immune response that can contribute to morbidity and death. Many people who survive PML are left with neurological sequelae and some with persistent, low-level viral replication in the CNS. As the number of people who survive PML increases, this lack of viral clearance could create challenges in the subsequent management of some underlying diseases.

In this Review, Cortese et al. provide an overview of the pathobiology and evolving presentations of progressive multifocal leukoencephalopathy and other diseases caused by JC virus, and discuss emerging immunotherapeutic approaches that could increase survival.

Progressive multifocal leukoencephalopathy (PML) is a rare, debilitating and often fatal disease of the CNS caused by JC virus (JCV).

JCV establishes asymptomatic, lifelong persistent or latent infection in immune competent hosts, but impairment of cellular immunity can lead to reactivation of JCV and PML.

PML most commonly occurs in patients with HIV infection or lymphoproliferative disease and in patients who are receiving natalizumab for treatment of multiple sclerosis.

The clinical phenotype of PML varies and is shaped primarily by the host immune response; changes in the treatment of underlying diseases associated with PML have changed phenotypes over time.

Other clinical manifestations of JCV infection have been described, including granule cell neuronopathy.

Survival of PML depends on reversal of the underlying immunosuppression; emerging immunotherapeutic strategies include use of checkpoint inhibitors and adoptive T cell transfer.

Rituximab experience in children with nephrotic syndrome: what have we observed differently

AIM

We aimed to evaluate the efficacy of rituximab therapy in children with nephrotic syndromes and to share our experiences.

MATERIAL AND METHODS

Twelve children with nephrotic syndrome (four with steroid-dependent, eight with steroid-resistant nephrotic syndrome) who were treated with rituximab were retrospectively evaluated in terms of clinical and laboratory data and CD19-20 levels. All patients received rituximab (375 mg/m2) once weekly for 4 weeks. A proteinuria-free period under steroid therapy was not sought prior to initiating rituximab therapy.

RESULTS

The overall remission rates in patients with steroid-dependent and steroid-resistant nephrotic syndrome were 100% and 27%. Focal segmental glomerulosclerosis was diagnosed in six patients and the remission rate was 33% in this population. CD19 cell depletion was observed in 10 of the 12 children. Seven of the 10 patients with CD19 depletion achieved remission, whereas the other three had persistent nephrotic proteinuria despite CD19 depletion. Two patients without CD19 depletion never achieved remission. Relapse occurred in three of the seven patients associated with increased CD19.

CONCLUSION

We observed that rituximab could be given without waiting for a proteinuria-free period under steroid therapy. Our result suggest that administering four weekly doses of rituximab increases the likelihood of remission, considering the amount of drug lost in the urine of children with nephrotic proteinuria. However, our findings must be confirmed with dose-comparison studies conducted with larger populations and an evaluation of long-term adverse effects. Some patients did not achieve remission despite B cell depletion, which suggests that B cell depletion is necessary but insufficient for remission in nephrotic syndromes.

Rituximab therapy for refractory steroid-resistant nephrotic syndrome in children

Patients with steroid-resistant nephrotic syndrome (SRNS) who develop resistance to immunosuppressive agents, defined as refractory SRNS, have poor renal outcomes. Although the chimeric anti-CD20 monoclonal antibody rituximab has shown efficacy for frequently relapsing nephrotic syndrome and steroid-dependent nephrotic syndrome, its efficacy for refractory SRNS remains uncertain due to limited data. According to previous case reports, 50.4% of patients with refractory SRNS showed clinical improvements after rituximab treatment. Remission rates in patients with initial steroid resistance and late steroid resistance were 43.9 and 57.7%, respectively, and 41.5 and 63.6% in patients with focal segmental glomerulosclerosis and minor glomerular abnormalities, respectively. However, various factors (race, disease severity, number of rituximab doses, concomitant treatments, and observation period) differed among these observational studies and their consensus may also have been affected by potential publication bias. Rituximab monotherapy may have some degree of efficacy and lead to satisfactory outcomes in a subset of patients with refractory SRNS. However, administration of concomitant treatments during rituximab-mediated B cell depletion, such as methylprednisolone pulse therapy, daily oral prednisolone therapy, and immunosuppressive agents, may lead to better outcomes in these patients. Large-scale, multi-center prospective studies are needed to evaluate the efficacy and safety of such regimens.

Both the rituximab dose and maintenance immunosuppression in steroid-dependent/frequently-relapsing nephrotic syndrome have important effects on outcomes

Rituximab is an effective treatment for steroid-dependent/ frequently-relapsing nephrotic syndrome (SDFRNS) in children. However, the optimal rituximab regimen remains unknown. To help determine this we conducted an international, multicenter retrospective study at 11 tertiary pediatric nephrology centers in Asia, Europe and North America of children 1-18 years of age with complicated SDFRNS receiving rituximab between 2005-2016 for 18 or more months follow-up. The effect of rituximab prescribed at three dosing levels: low (375mg/m²), medium (750mg/m²) and high (1125-1500mg/m²), with or without maintenance immunosuppression (defined as concurrent use of corticosteroids, mycophenolate motile or calcineurin inhibition at first relapse or for at least six months following the rituximab treatment) was examined. Among the 511 children (median age 11.5 year, 67% boys), 191, 208 and 112 received low, medium and high dose rituximab, respectively. Within this total cohort of 511 children, 283 (55%) received maintenance immunosuppression. Renal biopsies were performed in 317 children indicating the predominant histology was minimal change disease (74%). Without maintenance immunosuppression, low-dose rituximab had a shorter relapse-free period and a higher relapse risk (8.5 months) than medium (12.7 months; adjusted hazard ratio, 0.62) and high dose (14.3 months; adjusted hazard ratio, 0.50; all significant). With maintenance immunosuppression, the relapse-free survival in low-dose rituximab (14 months) was similar to medium (10.9 months; adjusted hazard ratio, 1.23) and high dose (12.0 months; adjusted hazard ratio, 0.92; all non-significant). Most adverse events were mild. Thus, children receiving low-dose rituximab without maintenance immunosuppression had the shortest relapse-free survival. Hence, both rituximab dose and maintenance immunosuppression have important effects on the treatment outcomes.

Efficacy of Rituximab vs Tacrolimus in Pediatric Corticosteroid-Dependent Nephrotic Syndrome: A Randomized Clinical Trial

IMPORTANCE

Calcineurin inhibitors are an established first-line corticosteroid-sparing therapy for patients with corticosteroid-dependent nephrotic syndrome (CDNS), whereas B-lymphocyte-depleting therapy is mostly used as a rescue for calcineurin inhibitor-resistant cases. The positive efficacy and safety profile of rituximab raises the question of whether it could be used as a first-line alternative to calcineurin inhibitor therapy.

OBJECTIVE

To compare the efficacy of rituximab and tacrolimus in maintaining relapse-free survival among children with CDNS.

DESIGN, SETTING, AND PARTICIPANTS

A parallel-arm, open-label, randomized clinical trial was performed from May 8, 2015, to September 20, 2016, with 1-year follow-up in a single-center, tertiary care unit. A total of 176 consecutive children aged 3 to 16 years with CDNS not previously treated with corticosteroid-sparing agents were screened for eligibility.

INTERVENTIONS

The children received either tacrolimus (along with tapering alternate-day prednisolone) for 12 months or a single course of rituximab (2 infusions of 375 mg/m2).

MAIN OUTCOMES AND MEASURES

Twelve-month relapse-free survival in the intention-to-treat population.

RESULTS

Of the 176 children screened for eligibility, 120 were randomized and all but 3 patients completed 1 year of follow-up. The groups were comparable, with mean (SD) age of 7.2 (2.8) years, 32 boys (53.3%) in each group, mean (SD) disease duration of 2.5 (1.5) years and 2.3 (1.7) in the tacrolimus and rituximab groups, respectively, disease duration less than 1 year among 15 children (25.0%) in each group, median (interquartile range) of 4 (3-5) relapses in each group, and mean (SD) cumulative prednisolone dose of 246 (48) mg/kg and 239 (52) mg/kg in the prestudy year in the tacrolimus and rituximab groups, respectively. Rituximab therapy was associated with a higher 12-month relapse-free survival rate than tacrolimus (54 [90.0%] vs 38 [63.3%] children; P < .001; odds ratio, 5.21; 95% CI, 1.93-14.07). Among the patients who experienced relapse, median time to first relapse was 40 weeks in the rituximab group and 29 weeks in the tacrolimus group. Only 2 patients in the rituximab group had more than 1 relapse during the study period compared with 10 patients in the tacrolimus group. The cumulative corticosteroid dose during the 12-month study period was lower with rituximab compared with tacrolimus (mean [SD], 25.8 [27.8] vs 86.3 [58.0] mg/kg). Although both treatments were well tolerated, mild to moderate infections were twice as common in the tacrolimus group (26 [43.3%] vs 13 [21.7%] events).

CONCLUSIONS AND RELEVANCE

In children with CDNS, rituximab appears to be more effective than tacrolimus in maintaining disease remission and minimizing corticosteroid exposure and, given its good tolerability and lack of nephrotoxic effects, may be considered as first-line corticosteroid-sparing therapy.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02438982; Clinical Trial Registry of India: CTRI/2014/01/004355.

Rituximab in The Management of Pediatric Steroid-Resistant Nephrotic Syndrome: A Systematic Review

OBJECTIVES

To evaluate the efficacy and safety of rituximab in children with steroid-resistant nephrotic syndrome.

STUDY DESIGN

A systematic review evaluating the efficacy and safety of rituximab in children with steroid-resistant nephrotic syndrome was performed. Data from studies, performed before April 2017 were collected, from MEDLINE, Cochrane Library, Scopus, and Web of Science. Study eligibility criteria included clinical trials and observational studies with a minimal sample size of 5 patients, regarding treatment with rituximab in children with steroid-resistant nephrotic syndrome. Independent extraction of articles by 2 investigators using predefined data fields was performed.

RESULTS

We included 7 case series and 1 open-label randomized controlled trial. Among them, 3 studies were multicenter. A total of 226 patients were included. Mean age at onset was 5.6 ± 1.1 years. Mean number of rituximab administrations was 3.1 ± 1.1 infusions per patient. Remission was observed in 89 patients (46.4%). Remission was seen in 40.8% patients with initial steroid-resistant nephrotic syndrome and 52.8% patients with late steroid-resistant nephrotic syndrome. Good initial response to rituximab therapy was observed in 63.2% patients with minimal change nephrotic syndrome, 39.2% patients with focal and segmental glomerulosclerosis, 1 patient had diffuse mesangial hypercellularity, and 1 patient had IgM nephropathy. Sustained remission ranged from 18% to 93.7%. Five serious adverse events were observed.

CONCLUSIONS

Rituximab exhibited a satisfactory profile regarding efficacy and safety indicating that this agent is a promising therapy for steroid-resistant nephrotic syndrome and should be further investigated by randomized clinical trials.

Rituximab in steroid-sensitive nephrotic syndrome: lessons from clinical trials

Idiopathic nephrotic syndrome is the most common chronic glomerular disease in children. A total of 80-90% of patients with childhood idiopathic nephrotic syndrome achieve remission with steroid therapy [steroid-sensitive nephrotic syndrome (SSNS)]. However, approximately 50% of children with SSNS develop frequently relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS). Children with FRNS or SDNS are usually treated with immunosuppressive agents, but 10-20% of children receiving immunosuppressive agents still show frequent relapses or steroid dependence during or after treatment, defined as complicated FRNS or SDNS. Rituximab, a chimeric anti-CD20 monoclonal antibody that was originally developed to treat patients with B-cell non-Hodgkin's lymphoma, is currently used for treating SSNS. In this review we highlight recent studies, mainly randomized controlled trials of rituximab for SSNS, including complicated and uncomplicated forms of FRNS or SDNS in children. We also discuss the effects of these studies on the management of patients suffering from these conditions.

Nephrotic syndrome in infants and children: pathophysiology and management

Nephrotic syndrome is defined by nephrotic-range proteinuria (≥40 mg/m²/hour or urine protein/creatinine ratio ≥200 mg/mL or 3+ protein on urine dipstick), hypoalbuminaemia (<25 g/L) and oedema. This review focuses on the classification, epidemiology, pathophysiology, management strategies and prognosis of idiopathic nephrotic syndrome of childhood, and includes a brief overview of the congenital forms.

Rituximab for nephrotic syndrome in children

Idiopathic nephrotic syndrome is the most common chronic glomerular disease in children. At least 20 % of children with this syndrome show frequent relapses and/or steroid dependence during or after immunosuppressive therapies, a condition defined as complicated frequently relapsing/steroid-dependent nephrotic syndrome (FRNS/SDNS). Approximately 1-3 % of children with idiopathic nephrotic syndrome are resistant to steroids and all immunosuppressive agents, a condition defined as refractory steroid-resistant nephrotic syndrome (SRNS); these SRNS children have a high risk of end-stage renal failure. Rituximab, a chimeric anti-CD20 monoclonal antibody, has been shown to be effective for patients with complicated FRNS/SDNS and refractory SRNS. This review describes the recent results of rituximab treatment applied to pediatric nephrotic syndrome, as well as those of our recent study, a multicenter, double-blind, randomized, placebo-controlled trial of rituximab for childhood-onset complicated FRNS/SDNS (RCRNS01). The overall efficacy and safety of rituximab for this disease are discussed.

The spectrum of opportunistic diseases complicating sarcoidosis

Sarcoidosis is an inflammatory disease marked by a paradoxical immune status. The anergic state, which results from various immune defects, contrasts with the inflammatory formation of granulomas. Sarcoidosis patients may be at risk for opportunistic infections (OIs) and a substantial number of cases have been reported, even in untreated sarcoidosis. It is not clear how OIs in patients with sarcoidosis are different from other groups at risk. In this review, we discuss the most common OIs: mycobacterial infection (including tuberculosis), cryptococcosis, progressive multifocal leukoencephalopathy, and aspergillosis. Unlike peripheral lymphocytopenia, corticosteroids are a major risk factor for OIs but the occurrence of Ols in untreated patients suggests more complex predisposing mechanisms. Opportunistic infections presenting with extrapulmonary features are often misdiagnosed as new localizations of sarcoidosis. Aspergillomas mostly develop on fibrocystic lungs. Overall, physicians should be aware of the possible occurrence of OIs during sarcoidosis, even in untreated patients.

Monoclonal Antibodies and Progressive Multifocal Leukoencephalopathy

Monoclonal antibodies have become an important treatment option for a number of serious conditions. Concerns have arisen about the potential association of these products with progressive multifocal leukoencephalopathy (PML). A list of monoclonal antibodies authorized for sale was derived from the Health Canada Drug Product Database. Case reports of PML after exposure to a monoclonal antibody authorized for use in Canada were retrieved by searching Canada Vigilance and WHO adverse event databases and through a Pub MED/Medline literature search. 182 adverse event case reports were retrieved (adalimumab -1 case, alemtuzumab-14, bevacizumab -3, cetuximab -1, efalizumab - 8, ibritumomab tiuxetan-5, infliximab-4, natalizumab-32, and rituximab-114). The Canadian Product Monographs for natalizumab and ritiximab contain box warnings for PML. A natalizumab registry has been established.

Variability of the impact of adverse events on physicians' decision making

Background

Physicians frequently differ in their treatment recommendations. However, few studies have examined the reasons underlying these differences. The objective of this study was to examine whether physicians vary in the importance they attach to specific adverse events for two treatment options found in recent randomized controlled trials to have equivalent efficacy and overall toxicity.

Methods

A Max-Diff survey was administered to physicians attending a national scientific conference to quantify the influence of 23 specific adverse events on decision making related to two treatment options for vasculitis. This approach was chosen because it results in greater item discrimination compared to rating scales. We used Hierarchical Bayes modeling to generate the relative importance score for each adverse event and examined the association between physicians’ characteristics and the five most influential factors.

Results

118 physicians completed the survey. The mean age (SD) was 48 years (10); 68% were male and 81% reported spending the majority of time in clinical practice. There was significant variability in the ratings of the relative importance of all adverse events, except those that were mild and easily reversible. We found a positive correlation between increasing physician age with ratings of sepsis (r = 0.29, p = 0.002) and opportunistic infection (r = 0.23, p = 0.016), and an inverse association between age with progressive multifocal leukoencephalopathy (r = - 0.28, p = 0.003). Physician sex, work setting, location, and number of patients with vasculitis seen per year were not associated with the influence of specific adverse events on decision making.

Conclusion

Our findings demonstrate that physicians differ substantially in how they perceive the importance of specific adverse events which may help explain observed unwarranted variability in physicians’ recommendations in clinical practice. Further efforts are needed to ensure that the reasons underlying variability in physicians’ recommendations are transparent.

Comprehensive evaluations of the adverse effects of drugs: importance of appropriate study selection and data sources

While systematic reviews and meta-analyses are at the top of the evidence hierarchy, most of the methodology has focused on assessing treatment benefit. Hence, we propose a structured framework for the initial steps of searching and identifying relevant data sources so that adverse effects can be evaluated in a comprehensive, unbiased manner. The unique methodological challenges stem from the difficulties of addressing diverse outcomes encompassing common, mild symptoms to rare, fatal events. Retrieval of the most appropriate studies should be specifically tailored to fit the nature of the adverse effects, according to the primary objective and study question. In our framework, the structure of the review takes different forms depending on whether the main aim is on scoping/hypothesis generation, or evaluating statistically the magnitude of risk (hypothesis testing), or clarifying characteristics and risk factors of the adverse effect. The wide range of data sources covering adverse effects all have distinct strengths and limitations, and selection of appropriate sources depends on characteristics of the adverse effect (e.g. background incidence and effect size of the drug, clinical presentation, time of onset after drug exposure). Reviewers need to retrieve particular study designs that are most likely to yield robust data on the adverse effects of interest, rather than rely on studies that cannot reliably detect adverse effects, and may yield 'false negatives'. Type II errors (a particular problem when evaluating rare adverse effects) can lull us into a false sense of security (e.g. wrongly concluding that there was no significant difference in harm between drug and control, with the drug erroneously judged as safe). Given the rapid rate at which methodological improvements occur, this proposed framework is by no means definitive, but aims to stimulate further debate and discussion amongst the pharmacoepidemiological and systematic review communities to reach a common consensus on the best methods.

Connective tissue disorders: systemic lupus erythematosus, Sjögren's syndrome, and scleroderma

Connective tissue disorders are systemic, autoimmune, multiorgan diseases in which the central and peripheral nervous systems are frequently involved. The objective of this chapter is to describe the neurological manifestations of three of the most common systemic autoimmune disorders: systemic lupus erythematosus (SLE), scleroderma, and Sjögren's syndrome (SS). In SLE the neuropsychiatric manifestations involve mainly the central nervous system (CNS), including cognitive dysfunction, headache, psychosis and mood changes, seizures, cerebrovascular disease, and myelopathy. Peripheral nervous system (PNS) manifestations are less common and include polyneuropathies as well as mononeuropathies and acute inflammatory demyelinating polyneuropathy. Antiphospholipid syndrome (APLS) is relatively common and should be searched for whenever focal neurological symptoms occur. In scleroderma the PNS is more commonly involved; symptoms include polyneuropathies, entrapment neuropathies, and mononeuropathies (mostly cranial neuropathies or mononeuritis multiplex). Additionally autonomic involvement occurs and myopathies are relatively common. In SS the PNS is similarly involved with several types of polyneuropathies, mononeuropathies, and autonomic dysfunction. Also common are myelopathies and aseptic meningitides. These and other, less common manifestations, as well as the diagnostic procedures and the therapeutic approaches, will be dealt with in this chapter.

Rituximab for induction and maintenance treatment of ANCA-associated vasculitides: a multicentre retrospective study on 80 patients

OBJECTIVES

Rituximab has been shown to induce remission of ANCA-associated vasculitides (AAVs). Our study was undertaken to describe AAV clinical responses to rituximab used for remission-induction and/or maintenance therapy, assess rituximab's safety profile and evaluate French clinical practices.

METHODS

This retrospective study concerned AAV patients who had received one or more rituximab infusion between 2002 and January 2011 and had follow-up lasting ≥12 months.

RESULTS

Eighty patients were included, most with refractory or relapsing AAV: 70 (88%) with granulomatosis with polyangiitis (GPA), 9 (11%) with microscopic polyangiitis and 1 (1%) with eosinophilic GPA. Rituximab was the first agent used to induce remission in 73 patients. The two most commonly administered regimens were an infusion of 375 mg/m(2)/week for 4 weeks (54 patients) and an infusion of 1 g every 2 weeks for a month (16 patients). Rituximab was first prescribed to maintain remission in seven patients. Respective 1-, 2-, and 3-year relapse-free survival rates after the first infusion were 80% (95% CI 72, 89), 63% (51, 77) and 52% (39, 70). Relapse-free survival was longer for patients receiving rituximab maintenance therapy (P = 0.002). Among 22 (28%) rituximab-treated patients experiencing severe adverse events, 12 (15%) had infectious complications leading to 4 (5%) deaths. Only 15 (19%) patients had received anti-pneumococcal vaccine before rituximab.

CONCLUSION

Rituximab was able to induce AAV remission and seemed to maintain remission better than other agents, but caution is needed concerning its safety, especially regarding bacterial infections, in this population.

Challenges and approaches for the development of safer immunomodulatory biologics

Immunomodulatory biologics are a class of biotechnology-derived therapeutic products that are designed to engage immune-relevant targets and are indicated in the treatment and management of a range of diseases, including immune-mediated inflammatory diseases and malignancies.

Despite their high specificity and therapeutic advantages, immmunomodulatory biologics have been associated with adverse reactions such as serious infections, malignancies and cytokine release syndrome, which arise owing to the on-target or exaggerated pharmacological effects of these drugs. Immunogenicity resulting in the generation of antidrug antibodies is another unwanted effect that leads to loss of efficacy and — rarely — hypersensitivity reactions.

For some adverse reactions, mitigating and preventive strategies are in place, such as stratifying patients on the basis of responsiveness to therapy and the risk of developing adverse reactions. These strategies depend on the availability of robust biomarkers for therapeutic efficacy and the risk of adverse reactions: for example, seropositivity for John Cunningham virus is a risk factor for progressive multifocal leukoencephalopathy. The development of effective biomarkers will greatly aid these strategies.

The development and design of safer immunomodulatory biologics is reliant on a detailed understanding of the nature of the disease, target biology, the interaction of the target with the immunomodulatory biologic and the inherent properties of the biologic that elicit unwanted effects.

The availability of in vitro and in vivo models that can be used to predict adverse reactions associated with immunomodulatory biologics is central to the development of safer immunomodulatory biologics. Some progress has been made in developing in vitro and in silico tests for predicting cytokine release syndrome and immunogenicity, but there is still a lack of models for effectively predicting infections and malignancies.

Two pathways can be followed in designing and developing safer immunomodulatory biologics. The first pathway involves generating a biologic that engages an alternative target or mechanism to produce the desired pharmacodynamic effect without the associated adverse reaction, and is followed when the adverse reaction cannot be dissociated from the target biology. The second pathway involves redesigning the biologic to 'engineer out' components within the biologic structure that trigger adverse effects or to alter the nature of the target–biologic interactions.

Owing to their specificity, immunomodulatory biologics generally have better safety profiles than small-molecule drugs. However, adverse effects such as an increased risk of infections or cytokine release syndrome are of concern. Here, Park and colleagues discuss the current strategies used to predict and mitigate these adverse effects and consider how they can be used to inform the development of safer immunomodulatory biologics.

Immunomodulatory biologics, which render their therapeutic effects by modulating or harnessing immune responses, have proven their therapeutic utility in several complex conditions including cancer and autoimmune diseases. However, unwanted adverse reactions — including serious infections, malignancy, cytokine release syndrome, anaphylaxis and hypersensitivity as well as immunogenicity — pose a challenge to the development of new (and safer) immunomodulatory biologics. In this article, we assess the safety issues associated with immunomodulatory biologics and discuss the current approaches for predicting and mitigating adverse reactions associated with their use. We also outline how these approaches can inform the development of safer immunomodulatory biologics.

Mechanisms of disease for the clinician: systemic lupus erythematosus

OBJECTIVE

To review the complex interactions and processes in systemic lupus erythematosus (SLE).

DATA SOURCES

Brief review of the important literature in peer-reviewed journals.

STUDY SELECTION

Studies on the clinical and immunologic features, pathogenesis, epidemiology, laboratory evaluation, and treatment of SLE are included in this review.

RESULTS

SLE may include a variety of disease entities, such as isolated cutaneous lupus, undifferentiated connective tissue disease, mixed connective tissue disease, and drug-induced lupus. There are many ongoing clinical trials in SLE patients of therapeutics with different mechanisms of cellular action, such as classic immunosuppression, cell depletion, antigen-specific immunomodulation, and targeting of antigen-nonspecific, immune-activating molecules. New immune cell-targeted therapies are now available that are specifically designed to block cellular pathways involved in disease pathogenesis.

CONCLUSION

The practicing physician should understand the immunology, pathogenesis, laboratory evaluation, and updated treatment options when diagnosing SLE in their clinic or daily practice.

Incidence of progressive multifocal leukoencephalopathy in patients with rheumatoid arthritis: a national population-based study

BACKGROUND

Cases of progressive multifocal leukoencephalopathy (PML), a rare but serious disease, have been reported in patients with rheumatoid arthritis (RA) in association with biological therapy, but little is known about the incidence of PML in patients with RA in the absence of treatment exposure.

OBJECTIVE

To estimate the incidence rate of PML in patients with RA compared with the general population, with and without exposure to biological agents.

METHODS

Patients with adult onset RA, exposure to biological agents and a diagnosis of PML from 1999 through 2009 were identified from national registries and linked using each Swedish resident's unique personal identification number. General population comparators matched on age, sex and county were also identified. Crude and age- and sex-standardised incidence rates (cases per 100 000 person-years) were calculated with 95% CI.

RESULTS

66 278 patients with RA and 286 949 general population comparators were included in the study. The incidence rate of PML in the overall RA population was 1.0 (95% CI 0.3 to 2.5) compared with 0.3 (95% CI 0.1 to 0.6) in the general population. The difference in incidence rate was 0.7 (95% CI -0.3 to 17). Among all patients exposed to biological agents, only one patient was diagnosed with PML.

CONCLUSION

Data from this national population-based cohort study suggest that patients with RA may have an increased rate of PML compared with the general population.

Incidence and risk factors for progressive multifocal leukoencephalopathy among patients with selected rheumatic diseases

OBJECTIVE

To ascertain the incidence of progressive multifocal leukoencephalopathy (PML) in patients with selected rheumatic diseases, to describe the characteristics of PML cases occurring in this setting, and to evaluate the extent to which such cases occurred in the context of biologic therapies such as rituximab or tumor necrosis factor antagonists.

METHODS

We conducted a large population-based study to describe the incidence and risk factors for PML among patients with rheumatoid arthritis, psoriatic arthritis, psoriasis, juvenile idiopathic arthritis, inflammatory bowel disease, and ankylosing spondylitis using national inpatient and outpatient administrative data from the entire Center for Medicare and Medicaid Services from 2000-2009. Suspected PML cases were identified using hospital discharge diagnosis codes. Risk factors for PML were evaluated using outpatient data ≥6 months prior to PML diagnosis.

RESULTS

Among 2,030,578 patients with autoimmune diseases of interest, a total of 53 PML cases were identified (2.6 per 100,000 patients). Most PML cases had human immunodeficiency virus (HIV) and/or cancer. Nine PML cases had evidence for biologic use prior to PML hospitalization, of which 3 had neither HIV nor malignancy and were exposed to biologics within 12 (rituximab) or 6 months (all other biologics) prior to PML diagnosis. PML occurred at an estimated incidence of 0.2 per 100,000 patients with autoimmune diseases who did not have HIV or malignancy.

CONCLUSION

PML occurs at a very low incidence among patients with rheumatic diseases but can occur even in the absence of HIV or malignancy.

Co-morbidities in established rheumatoid arthritis

Co-morbid conditions are common in patients with rheumatoid arthritis (RA). Although the presence of co-morbid conditions can be assessed using standardised indexes such as the Charlson index, most clinicians prefer to simply record their presence. Some co-morbidities are causally associated with RA and many others are related to its treatment. Irrespective of their underlying pathogenesis, co-morbidities increase disability and shorten life expectancy, thereby increasing both the impact and mortality of RA. Cardiac co-morbidities are the most crucial, because of their frequency and their negative impacts on health. Treatment of cardiac risk factors and reducing RA inflammation are both critical in reducing cardiac co-morbidities. Gastrointestinal and chest co-morbidities are both also common. They are often associated with drug treatment, including non-steroidal anti-inflammatory drug and disease-modifying drugs. Osteoporosis and its associated fracture risk are equally important and are often linked to long-term glucocorticoid treatment. The range of co-morbidities associated with RA is increasing with the recognition of new problems such as periodontal disease. Optimal medical care for RA should include an assessment of associated co-morbidities and their appropriate management. This includes risk factor modification where possible. This approach is essential to improve quality of life and reduce RA mortality. An area of genuine concern is the impact of treatment on co-morbidities. A substantial proportion is iatrogenic. As immunosuppression with conventional disease-modifying drugs and biologics has many associated risks, ranging from liver disease to chest and other infections, it is essential to balance the risks of co-morbidities against the anticipated benefits of treatment.

Small lymphocytic lymphoma in a patient with CREST syndrome

We report a case of a 61-year-old man with a history of CREST syndrome (calcinosis cutis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) who presented for evaluation of thrombocytopenia. He had evident cervical adenopathy and lymph node biopsy showed small lymphocytic lymphoma (SLL) with evident systemic adenopathy and bone marrow involvement. The patient achieved a complete remission with FCR (fludarabine/cyclophosphamide/rituximab) chemotherapy. About 30 cases of lymphomas are reported in the literature in association with systemic sclerosis. To our knowledge, there are no reports of a small lymphocytic lymphoma (SLL) in association with limited cutaneous systemic sclerosis with classic features of the CREST syndrome.

Progressive Multifocal Leukoencephalopathy in a HIV-Negative Patient with Small Lymphocytic Leukemia following Treatment with Rituximab

We describe a case of progressive multifocal leukoencephalopathy (PML) caused by infection with the human polyomavirus JC virus in a patient with B-cell small lymphocytic leukemia who was treated with rituximab. The first symptoms of PML appeared immediately following the last of five cycles of rituximab, cyclophosphamide and pentostatin. Magnetic resonance imaging revealed changes consistent with PML, although JC virus DNA was not detected by polymerase chain reaction assay of the cerebrospinal fluid. A stereotactic biopsy of the brain showed histological changes consistent with PML, while electron microscopy revealed JC virus particles attached to the nuclei of astrocytes. The patient was treated supportively but died 53 days after the initial onset of symptoms.

Polyoma virus-associated progressive multifocal leukoencephalopathy after renal transplantation: regression following withdrawal of mycophenolate mofetil

The 2008-released FDA safety report described a potential association between use of MMF and progressive multifocal leukoencephalopathy. We here report the case of an 11-yr-old kidney transplanted boy suffering from PML who showed rapid improvement parallel to withdrawal of MMF. This case contributes to the increasing knowledge on side effects of MMF treatment in children.

From Clinical Presentation to the Outcome: the Natural History of PML in a Portuguese Population of HIV Infected Patients

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system, associated with immunosuppression states. As there are only some non-published documents concerning PML in HIV infected patients in Portugal, we pretend to characterize natural history of PML infection in a population of HIV patients.

METHODS

We retrospectively reviewed, from 1992 to 2009, PML cases in a population of 724 HIV infected patients followed in our institution. Clinical, biological, imagery features and outcomes were characterized.

RESULTS

Twenty-five (3.45%) patients were identified as having PML. The mean time between HIV and PML diagnosis was 20.4 months. PML was the presentation of HIV infection in 40% of the patients, and 92% had CD4 T cell count lower than 200/mm(3). Paresis was the most common clinical presentation. No specific characteristics were found in cerebrospinal fluid and JCV DNA was positive in 3 of 7 patients. MRI revealed characteristic findings. Combined antiretroviral therapy was started or changed in 96% of the patients. Neurological condition got worse in 12 patients. From the 14 deaths, 5 were directly attributed to PML progression. Follow-up was lost in 8 patients.

CONCLUSIONS

PML was the presentation of HIV infection in more than 1/3 of patients, frequently associated with advanced immunocompromise. MRI sensitivity to PML is high, and JCV DNA determination in CSF was not revealed to be sensible. PML diagnosis should be taken into account in HIV patients presenting any neurological symptoms, and HIV infection should be suspected when radiological findings suggest PML lesions even in previously healthy individuals.

KEYWORDS

Progressive multifocal leukoencephalopathy; JC virus; Human immunodeficiency virus; Demyelinating disease.

Choice of Biologic Therapy for Patients with Rheumatoid Arthritis: The Infection Perspective

Biologicals revolutionized the treatment of Rheumatoid Arthritis (RA). The targeted suppression of key inflammatory pathways involved in joint inflammation and destruction allows better disease control, which, however, comes at the price of an elevated infection risk due to relative immunosuppression. The disease-related infection risk and the infection risk associated with the use of TNF-α inhibitors (infliximab, adalimumab, etanercept, golimumab and certolizumab pegol), rituximab, abatacept and tocilizumab are discussed. Risk factors clinicians need to take into account when selecting the most appropriate biologic therapy for RA patients, as well as precautions and screening concerning a number of specific infections, such as tuberculosis, intracellular bacterial infections, reactivation of chronic viral infections and HIV are reviewed.

Mapping the safety profile of biologicals: a disproportionality analysis using the WHO adverse drug reaction database, VigiBase

BACKGROUND

Biologicals have specific characteristics, as compared with the small molecule drugs, and carry specific risks. Safety problems, for example infliximab and the risk for tuberculosis, have been identified via spontaneous reports of suspected adverse drug reactions (ADRs). However, in general there is limited data on the nature of spontaneously reported suspected ADRs for biologicals.

OBJECTIVE

To map the safety profile of biologicals as compared with all other drugs. In addition, mechanistic classes of biologicals will be compared.

METHODS

Data was obtained from the ADR database (VigiBase) maintained by the WHO Collaborating Centre for International Drug Monitoring. A disproportionality analysis was performed in which case reports for biologicals and all other drugs (the reference group), reported between January 1995 and December 2008, were selected. Vaccines were not included in the analysis. Suspected ADRs were classified according to Medical Dictionary for Regulatory Activities (MedDRA) version 12.0 at the System Organ Class (SOC) level. Biologicals were classified into mechanistic classes: antibodies, cytokines, enzymes, growth factors, hormones (reference group), interferons, receptors and others/various. The safety profile of the biologicals versus all other drugs in the database and of the various mechanistic classes of biologicals was compared using the proportional reporting ratio (PRR).

RESULTS

191,004 case reports containing 546,474 suspected ADRs were reported for 62 different biologicals, and 2,556,209 case reports containing 8,761,522 suspected ADRs were reported for all other drugs (the reference group). It was found that two-thirds of all suspected ADRs reported for biologicals were reported for five active substances: etanercept (20.3%), interferon-beta-1a (15.6%), infliximab (11.6%), teriparatide (10.7%) and adalimumab (9.0%). Comparison of the safety profile of biologicals and the reference group showed that suspected ADRs for biologicals were more frequently reported in the SOCs 'Infections and infestations' (PRR 4.5), 'Surgical and medical procedures' (PRR 2.4) and 'Neoplasms benign, malignant and unspecified' (PRR 2.1), and less frequently reported in the SOCs 'Psychiatric disorders' (PRR 0.4), 'Vascular disorders' (PRR 0.4) and 'Pregnancy, puerperium and perinatal conditions' (PRR 0.4). Regarding the differences in safety profile between various mechanistic classes of biologicals, compared with hormones (reference group), 'Infections and infestations' were more frequently reported for receptors and antibodies. 'Neoplasms benign, malignant and unspecified' were more frequently reported for antibodies, cytokines, interferons and receptors, and less frequently for enzymes as compared with the reference group.

CONCLUSIONS

In VigiBase, five biologicals comprise two-thirds of the suspected ADRs reported for biologicals, which might distort the relation found between a specific biological and a specific adverse event in case of quantitative signal detection. Therefore the choice of reference group to be used in case of quantitative signal detection should be considered very carefully. This study confirmed that biologicals have a different safety profile compared with all other drugs in the database and, within the group of biologicals, differences exist between mechanistic classes. Infections are, for example, frequently reported for receptors and antibodies, which often have an immune compromising effect. Such predictable safety issues should be specifically studied by preregistration clinical trials and/or targeted pharmacovigilance. In addition, since not all adverse reactions can be predicted or detected during development, spontaneous reporting remains an important tool for the early detection of signals.

Targeting B cells with biologics in systemic lupus erythematosus

IMPORTANCE OF THE FIELD

The use of biologics as immune modulators in several autoimmune diseases has provided new tools to the physician's therapeutic armamentiarium and has led to improved patients' outcomes and quality of life. By producing autoantibodies, B cells in systemic lupus erythematosus (SLE) are key players in the pathogenesis of the disease and in its clinical manifestations. Therefore, biologics that target B cells in SLE aim at reducing the activity of these cells for the induction of remissions and/or amelioration of disease activity, reduction of organ involvement, and limitation of the complications and side effects caused by immunosuppressive therapies.

AREAS COVERED IN THIS REVIEW

This review describes the past and current clinical trials with B-cell-targeted biologics in SLE, to provide a historical perspective and the state-of-the-art on the topic.

WHAT THE READER WILL GAIN

We review how the disappointment in the field from promising agents has been instrumental in providing valuable lessons leading to an improved design of new trials that are now giving encouraging results.

TAKE HOME MESSAGE

In systemic lupus erythematosus (SLE), the use of B-cell-based biologics in clinical trials has shown both disappointment and promise.

Progressive multifocal leukoencephalopathy and promyelocytic leukemia nuclear bodies: a review of clinical, neuropathological, and virological aspects of JC virus-induced demyelinating disease

Progressive multifocal leukoencephalopathy is a fatal viral-induced demyelinating disease that was once rare but has become more prevalent today. Over the past decades, much has been learned about the disease from molecular study of the etiological agent of the disease, JC virus. Recently, promyelocytic leukemia nuclear bodies (PML-NBs), punctuate structures for important nuclear functions in eukaryotic cells, were identified as an intranuclear target of JC virus infection. Neuropathologically, JC virus-infected glial cells display diffuse amphophilic viral inclusions by hematoxylin–eosin staining (full inclusions), a diagnostic hallmark of this disease. Recent results using immunohistochemistry, however, revealed the presence of punctate viral inclusions preferentially located along the inner nuclear periphery (dot-shaped inclusions). Dot-shaped inclusions reflect the accumulation of viral progeny at PML-NBs, which may be disrupted after viral replication. Structural changes to PML-NBs have been reported for a variety of human diseases, including cancers and neurodegenerative disorders. Thus, PML-NBs may provide clues to the further pathogenesis of JC virus-induced demyelinating disease. Here, we review what we have learned since the disease entity establishment, including a look at recent progress in understanding the relationship between JC virus, etiology and PML-NBs.

JC virus T-Antigen DNA in gastrointestinal mucosa of immunosuppressed patients: a prospective, controlled study

BACKGROUND

JC virus (JCV), a polyoma virus, is the etiological agent of progressive multifocal leukoencephalopathy in immunosuppressed patients. JCV T-Ag has proven oncogenic potential and is expressed in colonic polyps and carcinomas. We proposed that the prevalence of JCV T-Ag DNA is higher in the normal gastrointestinal (GI) mucosa of immunosuppressed patients compared with their immunocompetent counterparts.

AIMS

To look for JCV T-Ag DNA in the normal gastrointestinal mucosa of immunosuppressed patients compared with immunocompetent controls.

METHODS

Macroscopically normal samples of upper and lower GI mucosa were obtained from 38 immunosuppressed patients. A control group included samples from 19 immunocompetent inflammatory bowel disease (IBD) and 29 non-IBD cases. DNA was extracted and polymerase chain reaction (PCR) was performed using primers specific for T-Ag.

RESULTS

JCV T-Ag DNA was found in nine of the immunosuppressed patients (23.7%) and in three of the controls (6.3%; P = 0.02). Transplant recipients had a particularly high prevalence of JCV T-Ag DNA (35.3%). Patients with IBD receiving immunosuppressive drugs had a higher prevalence of JCV T-Ag DNA in comparison with IBD patients who did not receive immunosuppression (22.2% versus 10.5%, respectively), but this difference was not statistically significant (P = 0.574).

CONCLUSION

JCV T-Ag DNA is more prevalent in the upper and lower GI mucosa of immunosuppressed patients, possibly indicating that the virus resides in these patients. This may account for the higher prevalence of GI carcinomas in immunosuppressed patients.

The point on the ongoing B-cell depleting trials currently in progress over the world in primary Sjögren's syndrome

Conventionnal therapy (moisturizers, pilocarpine, Cevimeline, local Cyclosporine, and hydroxychloroquine) remains the basis for the treatment of primary Sjögren's syndrome (pSS) but they do not modify the course of the disease. Rituximab is currently the most fully evaluated biologics in pSS. Open-label studies suggest that Rituximab is well tolerated (although infusion-related reactions and serum sickness remain possible), induces a rapid depletion of B cells in the blood and salivary glands, and could improve early active pSS or pSS with active extra glandular involvement. Two small double blind randomized studies have been conducted and now published, demonstrating its efficacy on fatigue and sicca syndrome in early disease. Two large double blind studies are currently ongoing or planned: The TEARS study (Tolerance and EfficAcy of Rituximab in primary Sjögren syndrome) in France, is currently including 120 patients having either a recent and active disease and/or at least one extraglandular severe signs. The 'TRACTISS' Study (Anti-B-Cell Therapy In Patients With Primary Sjögren's Syndrome), in UK, will include 100 patients having anti-Ro/La antibodies, reduced basal secretion but an increased salivary flow with stimulation, within 10years of diagnosis, symptomatic oral dryness, fatigue and at least one systemic feature.