Tryptophan immunoadsorption for the treatment of autoimmune encephalitis

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP): Current Therapies and Future Approaches

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired immune-mediated polyradiculoneuropathy leading to disability via inflammatory demyelination of peripheral nerves. Various therapeutic approaches with different mechanisms of action are established for the treatment of CIDP. Of those, corticosteroids, intravenous or subcutaneous immunoglobulin, or plasma exchange are established first-line therapies as suggested by the recently revised EAN/PNS guidelines for the management of CIDP. In special cases, immunosuppressants or rituximab may be used. Novel therapeutic approaches currently undergoing clinical studies include molecules or monoclonal antibodies interacting with Fc receptors on immune cells to alleviate immune-mediated neuronal damage. Despite various established therapies and the current development of novel therapeutics, treatment of CIDP remains challenging due to an inter-individually heterogeneous disease course and the lack of surrogate parameters to predict the risk of clinical deterioration.

Diagnostic approach and treatment regimens in adult patients suffering from antibody-mediated or paraneoplastic encephalitis

Identification of patients with antibody-mediated encephalitis poses a diagnostic challenge and any delay in that respect will increase the interval until initiation of immunotherapy and may negatively affect the patient´s clinical outcome. Within this review we focus on therapeutic strategies in antibody-mediated encephalitis and propose how to proceed with patients, who are suspected to have encephalitis of unknown origin. We further briefly outline differences in treatment of paraneoplastic and antibody-mediated encephalitis according to its pathomechanisms.

Successful treatment with immunoadsorption therapy in four patients with severe and refractory anti-N-methyl-D-aspartate receptor encephalitis

There is still no optimal treatment for patients with severe anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis refractory to first-line therapy (including intravenous methylprednisolone [IVMP] and intravenous immunoglobulin [IVIG]). A small study has shown that immunoadsorption (IA) is effective in treating anti-NMDAR encephalitis. However, the effectiveness and safety of IA in the treatment of patients with refractory and severe anti-NMDAR encephalitis is not fully known. Four patients with severe anti-NMDAR encephalitis are reported, which were refractory to the first-line immunotherapy including IVMP and IVIG. Immunoadsorption is performed during the fulminant stage of disease, and the effectiveness and safety of IA are assessed. The modified Rankin Scale (mRS) is used to assess neurological conditions before and after IA. Four patients with the most severe form of anti-NMDAR encephalitis (two with teratoma and two with unknown origin) did not respond to one or more rounds of IVMP plus IVIG. They all required intensive care unit (ICU) support including long-term mechanical ventilation, and thus developed ICU-related complications. Gradual and steady improvement was observed after IA treatment. Except for mild hypotension in patient 1, no other adverse events were observed during IA. Two patients had good early overall recovery on discharge. The other two patients had a good outcome with mRS of 2 at the 12-month follow-up. This small case series suggests that IA may be an effective treatment option to accelerate the recovery of patients with severe and refractory anti-NMDAR encephalitis.

Immunoadsorption with staphylococcal protein A column in autoimmune encephalitis

BACKGROUND

Early treatment has a positive effect on autoimmune encephalitis. However, different treatments have individual differences and corresponding contraindications in the clinical. Few reports have described the application of immunoadsorption with Staphylococcal Protein A Column (SPA-IA) in neuroimmune diseases. We aimed to observe the safety and efficiency of SPA-IA in autoimmune encephalitis.

PATIENTS AND METHODS

We retrospectively analyzed three cases of autoimmune encephalitis wherein the first-line treatment was ineffective or contraindicated. The clinical features and prognosis during and after SPA-IA are described in detail.

RESULTS

All patients were definitely diagnosed with autoimmune encephalitis. After treated with SPA-IA, all antibody titers, except for the serum antibody titer in Patient 2, were markedly decreased in both the cerebral spinal fluid and serum. The mean fibrinogen levels before and after SPA-IA were stable, and there were no clinical bleeding events. The modified Rankin Scale scores and their symptoms improved significantly after the last SPA-IA session or 3 months later.

CONCLUSIONS

SPA-IA may be a viable, efficacious, and safe treatment alternative for autoimmune encephalitis with contraindications to traditional treatment or poor response.

Protein A immunoadsorption for the treatment of refractory anti-N-methyl-d-aspartate receptor encephalitis: A single-center prospective study

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of protein A immunoadsorption (IA) for anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis resistant to intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG).

METHODS

We prospectively evaluated patients with refractory anti-NMDAR encephalitis, treated with protein A IA. Demographic data, clinical characteristics, modified Rankin Score (mRS), and anti-NMDAR antibodies were documented before and after IA and at follow-up. Clinical improvement was defined as a decrease of mRS ≥1. Adverse events were recorded throughout the study.

RESULTS

Ten patients with mRS ≥3 were enrolled and treated with protein A IA; treatment was performed for an average of 5.2 times per patient. Among the nine patients with positive serum anti-NMDAR, the titer decreased in seven patients, of which two became negative. The cerebrospinal fluid (CSF) anti-NMDAR titer decreased in all patients, and one became negative. Anti-NMDAR levels were tested in two patients at follow-up and found to have declined continuously. All patients exhibited clinical improvement with a mRS decline ≥1 after IA treatment (median mRS: 5.0 [range, 3.0-5.0] vs. 4.0 [range, 2.0-4.0], p = 0.014), and the median mRS decreased to 1.0 (range, 0-3.0) at follow-up. After IA, all patients exhibited accelerated recovery. No adverse events were observed during IA treatment.

CONCLUSION

Protein A IA may be effective for treating IVMP/IVIG-resistant anti-NMDAR encephalitis and well tolerated. It is necessary to initiate larger-scale prospective controlled studies to validate the efficacy and safety of protein A IA in anti-NMDAR encephalitis.

Neuropsychiatric Disorders Due to Limbic Encephalitis: Immunologic Aspect

Limbic encephalitis (LE) is a rare cause of encephalitis presenting as an acute and subacute onset of neuropsychiatric manifestations, particularly with memory deficits and confusion as core features, along with seizure occurrence, movement disorders, or autonomic dysfunctions. LE is caused by neuronal antibodies targeting the cellular surface, synaptic, and intracellular antigens, which alter the synaptic transmission, especially in the limbic area. Immunologic mechanisms involve antibodies, complements, or T-cell-mediated immune responses in different degree according to different autoantibodies. Sensitive cerebrospinal fluid markers of LE are unavailable, and radiographic findings may not reveal a typical mesiotemporal involvement at neurologic presentations; therefore, a high clinical index of suspicions is pivotal, and a neuronal antibody testing is necessary to make early diagnosis. Some patients have concomitant tumors, causing paraneoplastic LE; therefore, tumor survey and treatment are required in addition to immunotherapy. In this study, a review on the molecular and immunologic aspects of LE was conducted to gain awareness of its peculiarity, which we found quite different from our knowledge on traditional psychiatric illness.

Apheresis in Autoimmune Encephalitis and Autoimmune Dementia

Autoimmune encephalitis (AE) is a rapidly progressive inflammatory neurological disease. Underlying autoantibodies can bind to neuronal surfaces and synaptic proteins resulting in psychiatric symptoms, focal neurological signs, autonomic dysfunction and cognitive decline. Early and effective treatment is mandatory to reduce clinical symptoms and to achieve remission. Therapeutic apheresis, involving both plasma exchange (PE) and immunoadsorption (IA), can rapidly remove pathogenic antibodies from the circulation, thus representing an important first-line treatment in AE patients. We here review the most relevant studies regarding therapeutic apheresis in AE, summarizing the outcome for patients and the expanding clinical spectrum of treatment-responsive clinical conditions. For example, patients with slowly progressing cognitive impairment suggesting a neurodegenerative dementia can have underlying autoantibodies and improve with therapeutic apheresis. Findings are encouraging and have led to the first ongoing clinical studies assessing the therapeutic effect of IA in patients with anti-neuronal autoantibodies and the clinical presentation of dementia. Therapeutic apheresis is an established and well tolerated option for first-line therapy in AE and, potentially, other antibody-mediated central nervous system diseases.

Autoimmune Encephalitis: NMDA Receptor Encephalitis as an Example of Translational Neuroscience

Autoimmune encephalitis (AE) is a group of disorders causing synaptic receptor dysfunction with a broad range of neurological symptoms that has been historically difficult to differentiate clinically. Today, AE represents an excellent example of the rapid determination of the cause of a disease and the ability to identify potential treatments using relatively simple basic science techniques of investigation. Of the number of autoimmune encephalitides identified thus far, one of the best examples of the impact of basic science studies on disease management is NMDA receptor mediated autoimmune encephalitis (NMDAr-AE). In this review, we will provide an overview of the epidemiology of NMDAr-AE, clinical features and treatments, and the basic science tools and techniques that were used to identify the cause, correlate symptoms to underlying pathophysiology, and to understand the mechanism of disease pathology.

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

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

Efficacy of Therapeutic Plasma Exchange in Patients with Severe Refractory Anti-NMDA Receptor Encephalitis

The objective of the present study was to assess the efficacy of therapeutic plasma exchange (TPE) in patients with severe refractory anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis. Patients with severe anti-NMDA receptor encephalitis who showed no improvement after steroids and/or intravenous immunoglobulin treatment for at least 10 days were enrolled. All patients received immunotherapy and were divided into a TPE group and a non-TPE group according to treatment received. Each patient in the TPE group received at least 1 TPE course. NMDA receptor antibody titers in the cerebrospinal fluid (CSF) and plasma were evaluated within 1 week after the last TPE procedure. The clinical efficacy of treatment was evaluated after 1 month, 2 months, 3 months, 6 months, and 12 months. Forty patients were enrolled: 19 in the TPE group and 21 in the non-TPE group. Nineteen patients received TPE for a total of 118 procedures. NMDA receptor antibody titers in the CSF and/or plasma decreased or were negative after the last TPE procedure in 18 patients (94.7%). Compared with the non-TPE group, the TPE group exhibited greater clinical improvement after 1 month and 2 months following treatment (P < 0.05). After 3 months, 6 months, and 12 months, there were no significant differences in the outcomes between the TPE group and non-TPE group. The results suggest that TPE might rapidly improve the clinical manifestations in patients with severe refractory anti-NMDA receptor encephalitis, and we believe that TPE should be considered as a first-line treatment.

Overview of therapeutic plasma exchange in pediatric neurology: a single-center experience

Therapeutic plasma exchange (TPE) is used in the treatment of neurological, hematological, renal and autoimmune diseases with known or suspected immune pathogenesis. In comparison with neurological diseases of adults, knowledge about the use of TPE in children is incomplete. We report our experience on TPE in children with neurological diseases in a single institution and describe the underlying etiology, clinical course, treatment and outcome. We retrospectively evaluated 22 consecutive children (12 girls, 10 boys, aged 2-16 years) who underwent TPE in the pediatric intensive care unit between January 2010 and January 2017. There were 135 TPE procedures with median 6 TPE sessions per patient. Fresh frozen plasma was used as a replacement fluid in all cases. Most common indications were inflammatory polyneuropathy followed by acquired demyelinating diseases of the central nervous system. Other indications were autoimmune encephalitis and paraneoplastic limbic encephalitis. No mortality was recorded during TPE. The complication rate was 2.2% and consisted of transient events like hypotension and allergic reactions. Therapetic plasma exchange is one of the safe methods of treatment for neuroimmunological disorders in children, with Guillain-Barré syndrome as the most common indication.

Treatment strategies for autoimmune encephalitis

Autoimmune encephalitis is one of the most rapidly growing research topics in neurology. Along with discoveries of novel antibodies associated with the disease, clinical experience and outcomes with diverse immunotherapeutic agents in the treatment of autoimmune encephalitis are accumulating. Retrospective observations indicate that early aggressive treatment is associated with better functional outcomes and fewer relapses. Immune response to first-line immunotherapeutic agents (corticosteroids, intravenous immunoglobulin, plasma exchange, and immunoadsorption) is fair, but approximately half or more of patients are administered second-line immunotherapy (rituximab and cyclophosphamide). A small but significant proportion of patients are refractory to all first- and second-line therapies and require further treatment. Although several investigations have shown promising alternatives, the low absolute number of patients involved necessitates more evidence to establish further treatment strategies. In this review, the agents used for first- and second-line immunotherapy are discussed and recent attempts at finding new treatment options are introduced.

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

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

Immunoadsorption or plasma exchange in the treatment of autoimmune encephalitis: a pilot study

Therapeutic apheresis has emerged as a major treatment option for autoantibody-associated inflammatory diseases of the nervous system. This includes patients with autoimmune encephalitides caused by antibodies against neuronal proteins. Plasma exchange (PE) and immunoadsorption (IA) constitute two possibilities to eliminate pathogenic antibodies from patients' plasma, but their efficacy and safety has not been prospectively assessed in larger patient groups of autoimmune encephalitides. In a prospective observational case control study, we, therefore, investigated the disease courses and treatment effects of 21 patients with autoimmune encephalitis associated with NMDAR, LGI1, CASPR2, GAD, mGluR5 and Hu antibodies. Patients were randomly assigned to receive PE (n = 11) or IA (n = 10). Symptoms were evaluated using the modified Rankin Scale (mRS). Side effects or adverse events were recorded. Both interventions, IA (p = 0.014) and PE (p = 0.01), resulted in significant reduction of the median mRS. With IA, 60 % of the patients improved clinically by at least 1 mRS score, none worsened. PE led to a comparable symptom reduction in 67 % of the cases. During 83 PE sessions, three adverse events were documented, while no side effects occurred under IA. Symptom improvement was significantly associated with younger age (r = -0.58), but not with disease duration. Therapeutic apheresis was most effective for neuronal surface antigens (83.3 %), followed by intracellular-synaptic antigens (66.7 %). Both IA and PE resulted in moderate to marked clinical improvement, with a low rate of adverse events. Apheresis is well tolerated and effective also as first-line therapy in autoimmune encephalitis, particularly in patients with antibodies targeting neuronal surfaces.

Diagnostic and therapeutic strategies for management of autoimmune encephalopathies

INTRODUCTION

The understanding of the etio-pathogenesis of autoimmune encephalopathy syndromes has grown significantly in recent years. These are potentially reversible conditions, with variable clinical presentation and potential dramatic response to immunotherapy.

AREAS COVERED

In this article we review various diagnostic techniques and therapeutic options for management of autoimmune encephalopathy. We also review medication adverse effects and monitoring strategies. Expert commentary: Early diagnosis and immunomodulatory treatment remains the cornerstone of management, to halt the underlying neuro-inflammatory process and prevent permanent neuronal injury. The availability of serological testing and various imaging modalities has further improved detection of these immune-mediated neurological disorders. Understanding the mechanisms and potential adverse effects of immunomodulatory therapies will help physicians to choose the most favorable therapeutic strategy for each patient.

Immunoadsorption with regenerating systems in neurological disorders --A single center experience

In recent years, immunoadsorption is increasingly recognized as an alternative treatment approach replacing therapeutic plasma exchange in a variety of neurological disorders. While most experience is based on the application of single-use tryptophan adsorbers, less data exists on the application of more efficient regenerating adsorber columns. We here report the systematic use of a regenerating adsorber system in various neurological indications such as multiple sclerosis, encephalitis, myasthenia gravis and chronic inflammatory demyelinating polyneuropathy, providing the expected treatment success in regard to reduction of immunoglobulins and antibody clearance, together with a low rate of adverse events. As it has been shown for single-use columns before, immunoadsorption with regenerating adsorbers can be successfully applied in disorders without known specific antibodies such as multiple sclerosis. Regenerating systems offer the perspective to provide a more efficacious long term treatment perspective for such patients.

[Tryptophan immunoadsorption for multiple sclerosis and neuromyelitis optica: therapy option for acute relapses during pregnancy and breastfeeding]

BACKGROUND

Approximately 25 % of women with multiple sclerosis (MS) suffer clinically relevant relapses during pregnancy. Almost all disease-modifying drugs are contraindicated in pregnancy. High-dose glucocorticoids have some serious risks, especially within the first trimester. Tryptophan immunoadsorption (IA) provides a safe option to treat MS relapses during pregnancy.

OBJECTIVES

In this case series we describe for the first time the use of tryptophan IA for MS and neuromyelitis optica (NMO) relapses during pregnancy and breastfeeding.

PATIENTS AND METHODS

In this study a total of 9 patients were retrospectively analyzed of which 7 patients received IA treatment during pregnancy, 2 during breastfeeding and 4-6 tryptophan IA treatments were performed per patient with the single use tryptophan adsorber. Primary outcome was symptom improvement of the relapse.

RESULTS

In this study four patients with MS and one with NMO relapse during pregnancy were treated with IA without preceding glucocorticoid pulse therapy. The MS patients showed improvement in the expanded disability status scale (EDSS) by at least one point, the NMO patient showed significant improvement in visual acuity and two pregnant patients with steroid-refractory relapses showed clinically relevant improvement after IA. Of the patients two suffered from steroid-refractory relapses during breastfeeding and relapse symptoms improved in both cases after treatment with IA. All treatments were well tolerated and no serious adverse events occurred.

CONCLUSION

Tryptophan IA was found to be safe, well-tolerated and effective in the treatment of MS and NMO relapses during pregnancy and breastfeeding, sometimes without preceding glucocorticoid pulse therapy. A binding recommendation is limited without prospective clinical studies.