Progressive multifocal leukoencephalopathy in a patient with B-cell lymphoma during rituximab-containing chemotherapy: case report and review of the literature

JC Polyomavirus Infection Potentiated by Biologics

The risk of JC polyomavirus encephalopathy varies among biologic classes and among agents within the same class. Of currently used biologics, the highest risk is seen with natalizumab followed by rituximab. Multiple other agents have also been implicated. Drug-specific causality is difficult to establish because many patients receive multiple immunomodulatory medications concomitantly or sequentially, and have other immunocompromising factors related to their underlying disease. As use of biologic therapies continues to expand, further research is needed into pathogenesis, treatment, and prevention of JC polyomavirus encephalopathy such that risk for its development is better understood and mitigated, if not eliminated altogether.

Host-Immune Interactions in JC Virus Reactivation and Development of Progressive Multifocal Leukoencephalopathy (PML)

With the advent of immunomodulatory therapies and the HIV epidemic, the impact of JC Virus (JCV) on the public health system has grown significantly due to the increased incidence of Progressive Multifocal Leukoencephalopathy (PML). Currently, there are no pharmaceutical agents targeting JCV infection for the treatment and the prevention of viral reactivation leading to the development of PML. As JCV primarily reactivates in immunocompromised patients, it is proposed that the immune system (mainly the cellular-immunity component) plays a key role in the regulation of JCV to prevent productive infection and PML development. However, the exact mechanism of JCV immune regulation and reactivation is not well understood. Likewise, the impact of host factors on JCV regulation and reactivation is another understudied area. Here we discuss the current literature on host factor-mediated and immune factor-mediated regulation of JCV gene expression with the purpose of developing a model of the factors that are bypassed during JCV reactivation, and thus are potential targets for the development of therapeutic interventions to suppress PML initiation. Graphical Abstract.

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.

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.

Progressive Multifocal Leukoencephalopathy with Negative JC Virus PCR following Treatment of Follicular Lymphoma: Implications for Biologics in the Era of Targeted Cancer Therapy

Anticancer therapy predisposes patients to infections by the immunosuppression that results from treatment. Although 85% of patients with progressive multifocal leukoencephalopathy (PML) have concurrent HIV/AIDS, PML can also develop in patients after they receive chemotherapy for cancer. The case herein describes a 69-year-old man with history of follicular lymphoma who presented with progressive dysarthria and right-sided paralysis. He received rituximab one year prior to presentation. PET scan suggested no recurrence of lymphoma. Cerebrospinal fluid (CSF) analysis was negative and showed fewer than 500 copies/mL of JC virus. However, brain biopsy showed chromatin margination and viropathic change within oligodendrocytes, confirming PML. He was started on mirtazapine and mefloquine with some clinical improvement. To our knowledge, this is the first case of rituximab-associated PML in a patient with negative JC virus PCR from the CSF. Recognition of PML in the differential of oncology patients with CNS symptoms is an important consideration as we enter the era of targeted therapy and personalized cancer medicine involving biologics. Furthermore, screening of patients for presence of subclinical JC viremia prior to the use of biologics may be an important component of assessing patient candidacy for these agents.

Prophylaxis and Treatment of Pneumocystis jiroveci Pneumonia in Lymphoma Patients Subjected to Rituximab-Contained Therapy: A Systemic Review and Meta-Analysis

Pneumocystis jiroveci pneumonia (PCP) is frequently reported in lymphoma patients treated with rituximab-contained regimens. There is a trend toward a difference in PCP risk between bi- and tri-weekly regimens. The aims of this systemic review and meta-analysis were to estimate the risk for PCP in these patients, compare the impact of different regimens on the risk, and evaluate the efficacy of prophylaxis. The cohort studies with incept up to January 2014 were retrieved from the Cochrane Library, Medline, Embase, and Web of Science databases. Studies that compared the incidence of PCP in patients with and without rituximab treatment were conducted. Studies that reported the results of prophylaxis were concentrated to evaluate the efficacy of prophylaxis. Fixed effect Mantel-Haenszel model was chosen as the main analysis method. Funnel plots were examined to estimate the potential selection bias. Egger's test and Begg's test were used for the determination of possible small study bias. Eleven cohort studies that met the inclusion criteria were finally included. Results indicated that rituximab was associated with a significantly increased risk for PCP (28/942 vs 5/977; risk ratio: 3.65; 95% confidence interval 1.65 to 8.07; P=0.001), and no heterogeneity existed between different studies (I2=0%). Little significant difference in PCP risk was found between bi-weekly and tri-weekly regimens (risk ratio: 3.11; 95% confidence interval 0.92 to 10.52, P=0.068). PCP risk was inversely associated with prophylaxis in patients treated with rituximab (0/222 vs 26/986; risk ratio: 0.28; 95% confidence interval 0.09 to 0.94; P=0.039). In conclusion, PCP risk was increased significantly in lymphoma patients subjected to rituximab-contained chemotherapies. Difference in PCP risk between bi-weekly and tri-weekly regimens was not significant. Additionally, prophylaxis was dramatically effective in preventing PCP in rituximab-received lymphoma patients, suggesting that rituximab should be recommended for these patients.

Immunreconstitution and infectious complications after rituximab treatment in children and adolescents: what do we know and what can we learn from adults?

Rituximab, an anti CD20 monoclonal antibody, is widely used in the treatment of B-cell malignancies in adults and increasingly in pediatric patients. By depleting B-cells, rituximab interferes with humoral immunity. This review provides a comprehensive overview of immune reconstitution and infectious complications after rituximab treatment in children and adolescents. Immune reconstitution starts usually after six months with recovery to normal between nine to twelve months. Extended rituximab treatment results in a prolonged recovery of B-cells without an increase of clinically relevant infections. The kinetic of B-cell recovery is influenced by the concomitant chemotherapy and the underlying disease. Intensive B-NHL treatment such as high-dose chemotherapy followed by rituximab bears a risk for prolonged hypogammaglobulinemia. Overall transient alteration of immune reconstitution and infections after rituximab treatment are acceptable for children and adolescent without significant differences compared to adults. However, age related disparities in the kinetic of immune reconstitution and the definitive role of rituximab in the treatment for children and adolescents with B-cell malignancies need to be evaluated in prospective controlled clinical trials.

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.

Progressive Multifocal Leukoencephalopathy Following Treatment with Rituximab in an HIV-Negative Patient with Non-Hodgkin Lymphoma. A Case Report and Literature Review

Progressive multifocal leukoencephalopathy (PML) is a rare rapidly progressive demyelinating disease of the central nervous system caused by reactivation of latent John Cunningham (JC) polyomavirus (JCV) infection. We describe an unusual case of PML in a 54-year-old patient with follicular non-Hodgkin lymphoma who received rituximab plus cyclophosphamide, hydroxydaunorubicin, oncovicin and prednisolone (R-CHOP) therapy. She started to notice gradual progressive neurological symptoms about two months after completion of rituximab treatment and was therefore admitted to hospital. On admission, brain CT and MRI showed widespread lesions consistent with a demyelinating process involving the subcortical and deep white matter of the cerebral and cerebellar hemispheres. CT and MRI findings were suggestive of PML, and JC virus DNA was detected by polymerase chain reaction assay of the cerebrospinal fluid and serum. The patient was treated supportively but reported a progressive worsening of the clinical and radiological findings. Our report emphasizes the role of CT and MRI findings in the diagnosis of PML and suggests that PML should be considered in patients with progressive neurological disorders involving the entire nervous system and mainly the white matter, especially in the presence of previous immunomodulatory treatment or immunosuppression.

Central nervous system infections in cancer patients and hematopoietic stem cell transplant recipients

Central nervous system (CNS) infections in cancer patients present a diagnostic and therapeutic challenge for clinicians. While CNS infections are not frequent complications of cancer, its therapies, or hematopoietic stem cell transplantation, the importance of CNS infections lies in their propensity to result in profound morbidity and substantial mortality in this vulnerable patient population. With an expanding population of patients with malignant disease undergoing more potent and aggressive therapies and with the advent of newer immunomodulatory agents, the incidence of CNS infectious complications is likely to rise. This chapter will summarize the clinical and diagnostic evaluation of potential infections of the CNS in these patients and will discuss particular pathogens of interest with regard to this at-risk patient population.

Infections in vasculitis

Infections, mainly viral, are the cause of some vasculitides, like polyarteritis nodosa (hepatitis B virus) or mixed cryoglobulinemia (hepatitis C virus), and it has been hypothesized that others might be due to infectious agents (HIV, EBV, parvovirus...). Among etiologies of vasculitis, the responsibility of a Burkholderia-like strain has been recently demonstrated as the cause of giant-cell arteritis. On the other hand, patients frequently develop infections, mainly as a consequence of steroids, immunosuppressants and most immunomodulating treatments prescribed to treat vasculitides. Infections occur when patients receive steroids and immunosuppressants, especially in the long term. They are more frequently observed in elderly patients or in patients with poor general condition. Infection risk is not reduced when biotherapies are prescribed to induce or maintain remission. Patients, considered at higher risk for infections, should be followed closely and their immunological status monitored periodically. We recommend especially to monitor neutrophiles, lymphocytes and if needed CD3-, CD4- and CD8-cell counts in patients receiving steroids and cyclophosphamide or other cytotoxic agents. In patients treated with rituximab, CD19 and gammaglobulins should be monitored regularly. Prophylaxis are needed in patients at risk to develop infections.

Role of immunosuppressive therapy for the treatment of multiple sclerosis

Immunosuppressives have been used in multiple sclerosis (MS) since 1966. Today, we have many treatments for the relapsing forms of the disease, including 8 US Food and Drug Administration-approved therapies, with more soon to be introduced. Given the current treatment landscape what place do immunosuppressants have in combating MS? Trial work and our experience suggest that immunosuppressives still have an important role in treating MS. Cyclophosphamide finds use in treating patients with severe, inflammatory relapsing remitting MS or those suffering from a fulminant attack. We tend to employ mycophenolate mofetil as an add-on to injectable therapy for patients experiencing breakthrough activity. Some progressive (primary progressive multiple sclerosis or secondary progressive multiple sclerosis) patients may stabilize after treatment with either cyclophosphamide or mycophenolate. We rarely employ mitoxantrone because of potential cardiac or carcinogenic effects. We prefer to use cyclophosphamide or mycophenolate mofetil in preference to methotrexate because evidence of efficacy is limited for this drug. We have less experience with azathioprine, but it may be an alternative for patients with limited options who are unable to tolerate conventional therapies.

Practical considerations on the use of rituximab in autoimmune neurological disorders

Rituximab (Mabthera, Rituxan) is a chimeric human/murine monoclonal antibody against CD-20 surface antigen expressed on B-cells. Rituximab, by causing B-cell depletion, appears to be effective in several autoimmune disorders; it has been approved for rheumatoid arthritis and is a promising new agent in the treatment of several autoimmune neurological disorders. A controlled study in patients with relapsing remitting multiple sclerosis has shown that rituximab significantly reduces the number of new MRI lesions and improves clinical outcome; it also showed some promise in a subset of patients with primary progressive MS. The drug is also effective in a number of patients with Devic's disease, myasthenia gravis, autoimmune neuropathies, and inflammatory myopathies. The apparent effectiveness of rituximab has moved B-cells into the center stage of clinical and laboratory investigation of autoimmune neurological disorders. We review the evidence-based effectiveness of rituximab in neurological disorders based on controlled trials and anecdotal reports, including our own experience, and address the immunobiology of B-cells in autoimmune central nervous system (CNS) and peripheral nervous system (PNS) disorders. In addition, we provide practical guidelines on how best to use this drug in clinical practice and highlight its potential toxicity.

Progressive multifocal leukoencephalopathy in a patient with glioblastoma

Malignant gliomas are aggressive malignancies which inevitably recur despite multimodality treatment. In a subset of patients who are longer term survivors of this disease, progressive radiologic worsening can also occur from late effects of radiation rather than recurrent tumor, a differential diagnosis that is commonly considered in this setting. However, other causes for radiologic progression are not as well recognized and could potentially confound management leading to incorrect treatment decisions. Progressive multifocal leukoencephalopathy (PML) is a rare infectious demyelinating disease of the central nervous system seen primarily in immunocompromised patients, the early diagnosis and treatment of which remains a challenge. Here, we report a case of a long term survivor with glioblastoma whose diagnostic and therapeutic management was confounded by the development of PML. We review the radiological features and clinical course of this patient to highlight the dramatic neurological course in the setting of a highly malignant tumor, and emphasize the unusual changes in diffusion weighted images, and the need for clinical suspicion for early diagnosis of PML.

Efficacy and safety of rituximab in pediatric neuromyelitis optica

Neuromyelitis optica is a central nervous system disease characterized by optic neuritis and transverse myelitis. It is a devastating illness, and early treatment may prevent future relapses and severe disability. However, there is much variability in protocols used for treatment. In limited studies, rituximab has shown efficacy in adult neuromyelitis optica patients. There is a paucity of literature on the efficacy and tolerability of rituximab in the pediatric population. The authors report the use of rituximab in 2 pediatric patients with neuromyelitis optica, demonstrating its efficacy, dosing, and tolerability. This report may be a useful guide for administering rituximab safely in pediatric neuromyelitis optica patients.

Reactivation of hepatitis B virus following rituximab-plus-steroid combination chemotherapy

Reactivation of hepatitis B virus (HBV) has been reported as a fatal complication following systemic chemotherapy or other immunosuppressive therapy. The risk of HBV reactivation differs according to both the patient's HBV infection status prior to systemic chemotherapy and the degree of immunosuppression due to chemotherapy. For establishing an optimal strategy for hepatitis prevention and treatment, it is necessary to understand the characteristics, the clinical course and the risk factors for HBV reactivation and to recognize the difference between hepatitis B surface antigen (HBsAg)-positive and -negative patients with HBV reactivation. Among the important viral risk factors, HBV-DNA level and HBV-related serum markers have been reported to be associated with HBV reactivation in addition to cccDNA, genotypes and gene mutations. Rituximab-plus-steroid combination chemotherapy has recently been identified as a host risk factor for HBV reactivation in hepatitis B core antibody (anti-HBc)-positive and/or hepatitis B surface antibody (anti-HBs) positive--but nonetheless HBsAg-negative--lymphoma patients. For these patients with resolved hepatitis B, preemptive therapy guided by serial HBV-DNA monitoring is a reasonable strategy to enable early diagnosis of HBV reactivation and initiation of antiviral therapy. In this review, we summarize the characteristics of HBV reactivation following rituximab-plus-steroid combination chemotherapy, mainly in HBsAg-negative lymphoma patients, and propose a strategy for managing HBV reactivation.

Modified cyclophosphamide, vincristine, doxorubicin, and methotrexate (CODOX-M)/ifosfamide, etoposide, and cytarabine (IVAC) therapy with or without rituximab in Japanese adult patients with Burkitt lymphoma (BL) and B cell lymphoma, unclassifiable, with features intermediate between diffuse large B cell lymphoma and BL

The feasibility and efficacy of cyclophosphamide, vincristine, doxorubicin, and methotrexate (CODOX-M)/ifosfamide, etoposide, and cytarabine (IVAC) therapy in Japanese adult patients with Burkitt lymphoma (BL) and B cell lymphoma, unclassifiable, with features intermediate between diffuse large B cell lymphoma and BL (intermediate DLBCL/BL) have never been reported. The effects of adding rituximab to CODOX-M/IVAC have not been published either. Fifteen consecutive patients with a median age of 39 years were treated with modified CODOX-M/IVAC regimen (particularly, reducing the dose of methotrexate to 3 g/m(2)) with or without rituximab at our institution. Although all patients developed grade 4 neutropenia and grade 3/4 thrombocytopenia/anemia, 93% had febrile neutropenia, 60% showed transaminase elevation, and 40% had mucositis/stomatitis (all grade 3), there were no treatment-related deaths. Two of nine patients treated with rituximab developed biphasic late-onset neutropenia. Thirteen patients (87%) showed complete responses. The remaining two patients had refractory disease; one had presented with peritoneal dissemination and complex chromosomal abnormalities, while the other had double IGH-MYC and IGH-BCL2 translocations. The estimated 5-year overall and progression-free survival were 87% each, with a median follow-up of 74 months. In conclusion, our modified CODOX-M/IVAC regimen is well tolerated and highly effective in Japanese adult patients with BL and intermediate DLBCL/BL, warranting a larger study for confirmation.

Rituximab-associated infections

After more than 10 years of use, rituximab has proven to be remarkably safe. However, accumulated evidence now suggests that under some circumstances it may significantly increase the risk of infections. This risk is difficult to quantify because of confounding factors (namely, concomitant use of immunosuppressive or chemotherapeutic agents and underlying conditions), as well as under-reporting. Increased number of infections has been documented in patients treated with maintenance rituximab for low-grade lymphoma and in patients with concomitant severe immunodeficiency, whether caused by human immunodeficiency virus (HIV) infection or immunosuppressive agents like fludarabine. From the practical standpoint, the most important infection is hepatitis B reactivation, which may be delayed and result in fulminant liver failure and death. Special care should be placed on screening for hepatitis B virus (HBV) and preemptive antiviral treatment. Some investigators have reported an increase in Pneumocystis pneumonia. Finally, there is increasing evidence of a possible association with progressive multifocal leukoencephalopathy (PML), a lethal encephalitis caused by the polyomavirus JC. This review enumerates the described infectious complications, summarizes the possible underlying mechanisms of the increased risk, and makes recommendations regarding prevention, diagnosis and management.

Rituximab in chronic lymphocytic leukemia

Rituximab is a class I chimeric anti-CD20 antibody that has shown efficacy in chronic lymphocytic leukemia (CLL), both as a single agent and in combination with traditional chemotherapies. The modest activity demonstrated in early studies evaluating rituximab in relapsed CLL was improved with higher doses or more dose-intensive regimens that overcame the unfavorable pharmacokinetic features commonly found in CLL. These studies led to a variety of combination trials of rituximab with chemotherapy, where both phase II and later phase III studies have shown great promise for the advancement of CLL therapy. Despite the therapeutic success of rituximab in CLL, studies demonstrating the definitive relative mechanism of tumor clearance are still lacking and this requires further investigation. In addition to being used as a therapy for CLL, rituximab is an effective treatment for autoimmune CLL complications such as hemolytic anemia and immune thrombocytopenia (ITP). Patients with CLL may experience early infusion-related side effects that can be diminished with corticosteroid pretreatment and stepped-up dosing. Risk factors for infusion-related toxicity may relate to atypical CLL expressing bright CD20 antigen expression, although several different studies have not clearly implicated elevated white blood cell count as a risk factor. Other adverse events, including delayed cytopenias, reactivation of hepatitis B, and development of progressive multifocal leukoencephalopathy, are rare. Future efforts focusing on novel combination-based strategies will be required to fully appreciate the benefit of this therapy in CLL.

B cells as under-appreciated mediators of non-auto-immune inflammatory disease

B lymphocytes play roles in many auto-immune diseases characterized by unresolved inflammation, and B cell ablation is proving to be a relatively safe, effective treatment for such diseases. B cells function, in part, as important sources of regulatory cytokines in auto-immune disease, but B cell cytokines also play roles in other non-auto-immune inflammatory diseases. B cell ablation may therefore benefit inflammatory disease patients in addition to its demonstrated efficacy in auto-immune disease. Current ablation drugs clear both pro- and anti-inflammatory B cell subsets, which may unexpectedly exacerbate some pathologies. This possibility argues that a more thorough understanding of B cell function in human inflammatory disease is required to safely harness the clinical promise of B cell ablation. Type 2 diabetes (T2D) and periodontal disease (PD) are two inflammatory diseases characterized by little autoimmunity. These diseases are linked by coincident presentation and alterations in toll-like receptor (TLR)-dependent B cell cytokine production, which may identify B cell ablation as a new therapy for co-affected individuals. Further analysis of the role B cells and B cell cytokines play in T2D, PD and other inflammatory diseases is required to justify testing B cell depletion therapies on a broader range of patients.

Molecular regulation of JC virus tropism: insights into potential therapeutic targets for progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a growing concern for patients undergoing immune modulatory therapies for treatment of autoimmune diseases such as multiple sclerosis. Currently, there are no drugs approved for the treatment of PML that have been demonstrated in the patient to effectively and reproducibly alter the course of disease progression. The human polyoma virus JC is the causative agent of PML. JC virus (JCV) dissemination is tightly controlled by regulation of viral gene expression from the promoter by cellular transcription factors expressed in cells permissive for infection. JCV infection likely occurs during childhood, and latent virus containing PML-associated promoter sequences is maintained in lymphoid cells within the bone marrow. Because development of PML is tightly linked to suppression and or modulation of the immune system as in development of hematological malignancies, AIDS, and monoclonal antibody treatments, further scrutiny of the course of JCV infection in immune cells will be essential to our understanding of development of PML and identification of new therapeutic targets.

Progressive multifocal leukoencephalopathy in myelodysplastic syndrome involving pure red cell aplasia

Progressive multifocal leukoencephalopathy (PML) is a rare and fatal demyelinating disease of the central nervous system caused by JC polyomavirus (JCV) reactivation in an immunocompromised host. We describe a case of PML in a 76-year-old woman with myelodysplastic syndrome, who had been treated with azathioprine for a pure red cell aplasia-like condition. PML was diagnosed based on the neurologic symptoms, the magnetic resonance imaging patterns and the detection of JCV DNA in the cerebrospinal fluid. She died ten months after the diagnosis. An autopsy confirmed the diagnosis, and JCV DNA was detected in the cerebrum. Azathioprine might have triggered PML.

CNS elevation of vascular and not mucosal addressin cell adhesion molecules in patients with multiple sclerosis

The mucosal addressin cell adhesion molecule (MAdCAM) and vascular cell adhesion molecule (VCAM) appear to play roles in the recruitment of leukocytes to specialized endothelium lining the gastrointestinal tract. The purpose of this study was to clarify the role of MAdCAM and VCAM in the central nervous system by comparing protein expression in patients with multiple sclerosis (MS) and control subjects by immunohistochemistry. Specific antibodies to human VCAM and MAdCAM were used to confirm expression in control and MS nervous system specimens by immunohistochemistry. VCAM immunoreactivity was detected in endothelial cells, perivascular tissue, and in some cases, leukocytes within the meninges, gray, and white matter, of both controls and MS patients. VCAM immunoreactivity was maximal in a patient with acute active plaques, but of lower intensity and reduced distribution in controls and those with chronic active or inactive MS plaques. In contrast, MAdCAM immunoreactivity could not be detected in brain tissue from unaffected or MS patients. Taken together, these data support a role of VCAM, but not MAdCAM in the development of MS.

Progressive multifocal leukoencephalopathy after rituximab therapy in HIV-negative patients: a report of 57 cases from the Research on Adverse Drug Events and Reports project

Rituximab improves outcomes for persons with lymphoproliferative disorders and is increasingly used to treat immune-mediated illnesses. Recent reports describe 2 patients with systemic lupus erythematosus and 1 with rheumatoid arthritis who developed progressive multifocal leukoencephalopathy (PML) after rituximab treatment. We reviewed PML case descriptions among patients treated with rituximab from the Food and Drug Administration, the manufacturer, physicians, and a literature review from 1997 to 2008. Overall, 52 patients with lymphoproliferative disorders, 2 patients with systemic lupus erythematosus, 1 patient with rheumatoid arthritis, 1 patient with an idiopathic autoimmune pancytopenia, and 1 patient with immune thrombocytopenia developed PML after treatment with rituximab and other agents. Other treatments included hematopoietic stem cell transplantation (7 patients), purine analogs (26 patients), or alkylating agents (39 patients). One patient with an autoimmune hemolytic anemia developed PML after treatment with corticosteroids and rituximab, and 1 patient with an autoimmune pancytopenia developed PML after treatment with corticosteroids, azathioprine, and rituximab. Median time from last rituximab dose to PML diagnosis was 5.5 months. Median time to death after PML diagnosis was 2.0 months. The case-fatality rate was 90%. Awareness is needed of the potential for PML among rituximab-treated persons.

Make the grade for Wegener's granulomatosis after kidney transplantation

Antineutrophil cytoplasmic antibodies-associated vasculitis (AAV) is a well-described cause of multiple organ involvement including rapidly progressive pauci-immune crescentic glomerulonephritis. Kidney transplantation (KTx) is considered the treatment of choice in patients with end-stage renal disease (ESRD) due to AAV. Patient and graft survival in AAV after KTx is favourable and comparable with other non-diabetic causes of ESRD. While relapse of AAV is high in dialysis patients (up to 50%), it decreases after KTx (8.6–22.2%). Yet, relapse may occur at any time after KTx and transplant involvement has been documented in at least 25 cases. Therapeutic guidelines for the management of AAV after KTx do not exist and clinical management is a controversial discussion. We present two unusual cases of young males with smouldering AAV who recently underwent KTx at our hospital. Case 1 experienced repeated relapses after KTx and was finally successfully treated with rituximab. Case 2 received rituximab pre-emptively before living kidney donation and remained free of flairs. Prompted by theses two cases, we reviewed the literature focusing on the right point of time for transplantation, risk assessment, role of antineutrophil cytoplasmic antibodies, clinical presentation of flairs and immunosuppression in smouldering Wegener's granulomatosis (WG) and in relapse, including individualized treatment with rituximab.