Intravenous immunoglobulin for chronic inflammatory demyelinating polyradiculoneuropathy

Prospective open-label trial with rituximab in patients with chronic inflammatory demyelinating polyradiculoneuropathy not responding to conventional immune therapies

BACKGROUND

To evaluate the efficacy of rituximab in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients not responding to conventional immune therapies.

METHODS

An open-label, prospective exploratory study was conducted with intravenous rituximab on 17 CIDP patients who had not responded to at least two first-line therapies. The primary endpoint was to determine the proportion of patients who showed improvement 6 months after rituximab therapy. The percentage of responders to rituximab, along with a 95% CI, was reported and compared with the 30% response rate after other immunosuppressive drugs previously documented in the literature.

RESULTS

13 of the 17 treated patients (76.5%) showed improvement at 6 months (95% CI 50.1 to 93.2). Among the 14 patients who completed the 12-month follow-up (2 were lost to follow-up after showing improvement at months 8 and 10, and 1 deteriorated at 6 months), 13 (92.9%) demonstrated improvement at 12 months (95% CI 66.1 to 99.8). Nerve conduction parameters improved by at least 20% in two nerves in 6 out of 15 (40%) patients at 6 months and in 7 out of 13 (53.9%) at 12 months. None of the treated patients withdrew from the study due to side effects. There was a significant reduction of circulating CD19+ cells 15 days, 2, 6 and 12 months after treatment.

CONCLUSION

Rituximab seems to be a safe therapy in most patients with CIDP not responding to conventional immune therapies. The high percentage of patients who improved in this study suggests a possible positive effect of rituximab which is worth investigating in future randomised controlled clinical trials.

TRIAL REGISTRATION NUMBER

NCT05877040.

Chronic Inflammatory Demyelinating Polyradiculoneuropathy: Current Therapeutic Approaches and Future Outlooks

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a treatable autoimmune disorder, for which different treatment options are available. Current first-line evidence-based therapies for CIDP include intravenous and subcutaneous immunoglobulins, corticosteroids and plasma exchanges. Despite lack of evidence, cyclophosphamide, rituximab and mycophenolate mofetil are commonly used in circumstances of refractoriness and, more debatably, of perceived overdependence on first-line therapies. Rituximab is currently the object of a randomized controlled trial for CIDP. Based on case series, and although rarely considered, haematopoietic autologous stem cell transplants may be effective in refractory disease, with low mortality and high remission rates. A new therapeutic option has appeared with efgartigimod, a neonatal Fc receptor blocker, recently shown to significantly lower relapse rate versus placebo, after withdrawal from previous immunotherapy. Other neonatal Fc receptor blockers, nipocalimab and batoclimab, are under study. The C1 complement-inhibitor SAR445088, acting in the proximal portion of the classical complement system, is currently the subject of a new study in treatment-responsive, refractory and treatment-naïve subjects. Finally, Bruton Tyrosine Kinase inhibitors, which exert anti-B cell effects, may represent another future research avenue. The widening of the therapeutic armamentarium enhances the need for improved evaluation of treatment effects and reliable biomarkers in CIDP.

Intravenous immunoglobulin for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) causes progressive or relapsing weakness and numbness of the limbs, which lasts for at least two months. Uncontrolled studies have suggested that intravenous immunoglobulin (IVIg) could help to reduce symptoms. This is an update of a review first published in 2002 and last updated in 2013.

OBJECTIVES

To assess the efficacy and safety of intravenous immunoglobulin in people with chronic inflammatory demyelinating polyradiculoneuropathy.

SEARCH METHODS

We searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, and two trials registers on 8 March 2023.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) and quasi-RCTs that tested any dose of IVIg versus placebo, plasma exchange, or corticosteroids in people with definite or probable CIDP.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcome was significant improvement in disability within six weeks after the start of treatment, as determined and defined by the study authors. Our secondary outcomes were change in mean disability score within six weeks, change in muscle strength (Medical Research Council (MRC) sum score) within six weeks, change in mean disability score at 24 weeks or later, frequency of serious adverse events, and frequency of any adverse events. We used GRADE to assess the certainty of evidence for our main outcomes.

MAIN RESULTS

We included nine RCTs with 372 participants (235 male) from Europe, North America, South America, and Israel. There was low statistical heterogeneity between the trial results, and the overall risk of bias was low for all trials that contributed data to the analysis. Five trials (235 participants) compared IVIg with placebo, one trial (20 participants) compared IVIg with plasma exchange, two trials (72 participants) compared IVIg with prednisolone, and one trial (45 participants) compared IVIg with intravenous methylprednisolone (IVMP). We included one new trial in this update, though it contributed no data to any meta-analyses. IVIg compared with placebo increases the probability of significant improvement in disability within six weeks of the start of treatment (risk ratio (RR) 2.40, 95% confidence interval (CI) 1.72 to 3.36; number needed to treat for an additional beneficial outcome (NNTB) 4, 95% CI 3 to 5; 5 trials, 269 participants; high-certainty evidence). Since each trial used a different disability scale and definition of significant improvement, we were unable to evaluate the clinical relevance of the pooled effect. IVIg compared with placebo improves disability measured on the Rankin scale (0 to 6, lower is better) two to six weeks after the start of treatment (mean difference (MD) -0.26 points, 95% CI -0.48 to -0.05; 3 trials, 90 participants; high-certainty evidence). IVIg compared with placebo probably improves disability measured on the Inflammatory Neuropathy Cause and Treatment (INCAT) scale (1 to 10, lower is better) after 24 weeks (MD 0.80 points, 95% CI 0.23 to 1.37; 1 trial, 117 participants; moderate-certainty evidence). There is probably little or no difference between IVIg and placebo in the frequency of serious adverse events (RR 0.82, 95% CI 0.36 to 1.87; 3 trials, 315 participants; moderate-certainty evidence). The trial comparing IVIg with plasma exchange reported none of our main outcomes. IVIg compared with prednisolone probably has little or no effect on the probability of significant improvement in disability four weeks after the start of treatment (RR 0.91, 95% CI 0.50 to 1.68; 1 trial, 29 participants; moderate-certainty evidence), and little or no effect on change in mean disability measured on the Rankin scale (MD 0.21 points, 95% CI -0.19 to 0.61; 1 trial, 24 participants; moderate-certainty evidence). There is probably little or no difference between IVIg and prednisolone in the frequency of serious adverse events (RR 0.45, 95% CI 0.04 to 4.69; 1 cross-over trial, 32 participants; moderate-certainty evidence). IVIg compared with IVMP probably increases the likelihood of significant improvement in disability two weeks after starting treatment (RR 1.46, 95% CI 0.40 to 5.38; 1 trial, 45 participants; moderate-certainty evidence). IVIg compared with IVMP probably has little or no effect on change in disability measured on the Rankin scale two weeks after the start of treatment (MD 0.24 points, 95% CI -0.15 to 0.63; 1 trial, 45 participants; moderate-certainty evidence) or on change in mean disability measured with the Overall Neuropathy Limitation Scale (ONLS, 1 to 12, lower is better) 24 weeks after the start of treatment (MD 0.03 points, 95% CI -0.91 to 0.97; 1 trial, 45 participants; moderate-certainty evidence). The frequency of serious adverse events may be higher with IVIg compared with IVMP (RR 4.40, 95% CI 0.22 to 86.78; 1 trial, 45 participants, moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Evidence from RCTs shows that IVIg improves disability for at least two to six weeks compared with placebo, with an NNTB of 4. During this period, IVIg probably has similar efficacy to oral prednisolone and IVMP. Further placebo-controlled trials are unlikely to change these conclusions. In one large trial, the benefit of IVIg compared with placebo in terms of improved disability score persisted for 24 weeks. Further research is needed to assess the long-term benefits and harms of IVIg relative to other treatments.

Challenges in the Early Diagnosis and Treatment of Chronic Inflammatory Demyelinating Polyradiculoneuropathy in Adults: Current Perspectives

Diagnosing Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) poses numerous challenges. The heterogeneous presentations of CIDP variants, its mimics, and the complexity of interpreting electrodiagnostic criteria are just a few of the many reasons for misdiagnoses. Early recognition and treatment are important to reduce the risk of irreversible axonal damage, which may lead to permanent disability. The diagnosis of CIDP is based on a combination of clinical symptoms, nerve conduction study findings that indicate demyelination, and other supportive criteria. In 2021, the European Academy of Neurology (EAN) and the Peripheral Nerve Society (PNS) published a revision on the most widely adopted guideline on the diagnosis and treatment of CIDP. This updated guideline now includes clinical and electrodiagnostic criteria for CIDP variants (previously termed atypical CIDP), updated supportive criteria, and sensory criteria as an integral part of the electrodiagnostic criteria. Due to its many rules and exceptions, this guideline is complex and misinterpretation of nerve conduction study findings remain common. CIDP is treatable with intravenous immunoglobulins, corticosteroids, and plasma exchange. The choice of therapy should be tailored to the individual patient's situation, taking into account the severity of symptoms, potential side effects, patient autonomy, and past treatments. Treatment responses should be evaluated as objectively as possible using disability and impairment scales. Applying these outcome measures consistently in clinical practice aids in recognizing the effectiveness (or lack thereof) of a treatment and facilitates timely consideration of alternative diagnoses or treatments. This review provides an overview of the current perspectives on the diagnostic process and first-line treatments for managing the disease.

The use of intravenous immunoglobulin in the treatment of Hashimoto's encephalopathy: case based review

Background

Hashimoto's encephalopathy (HE) is a controversial immunological neuropsychiatric disease, with a poorly understood pathogenesis. It is characterized by symptoms of acute or subacute encephalopathy which usually occur in the presence of elevated levels of antithyroid antibodies. Even though it is also known as steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT), some cases appear to be steroid-resistant. This review examined whether treatment of Hashimoto's encephalopathy with intravenous immunoglobulin (IVIG) is associated with better clinical outcomes than the standard therapy. Additionally, we presented a case of a 59-year-old man who presented with severe neurological manifestations and was successfully treated with intravenous immunoglobulin.

Methods

The online databases PubMed and EMBASE were searched.

Results

A total of 1,365 articles were identified. After the deletion of 112 duplicates, 1,253 studies were screened by evaluating the title and abstract, focusing on Hashimoto's encephalopathy cases where IVIG were used. 846 studies were excluded because they were not relevant to the topic or included pediatric population. Therefore, 407 full-text articles were assessed for eligibility. The final analysis included 14 eligible articles after 393 were excluded (irrelevant texts, not written in English, full-text not available). In the majority of the selected case-reports, IVIG was associated with a good outcome, sometimes even with dramatic improvements in patient's status.

Conclusion

In last years, intravenous immunoglobulin therapy proved its utility in Hashimoto's encephalopathy's treatment, being a well tolerated therapy associated with remarkable improvement in patient's status. Further research is still needed in order to define the optimal treatment protocol for Hashimoto's encephalopathy and to establish if intravenous immunoglobulin can also be used as a first-line therapy, alone or in combination with steroids.

Introducing electronic monitoring of disease activity in patients with chronic inflammatory demyelinating polyneuropathy (EMDA CIDP): trial protocol of a proof of concept study

INTRODUCTION

Chronic inflammatory demyelinating polyneuropathy (CIDP) is one of the most common immune neuropathies leading to severe impairments in daily life. Current treatment options include intravenous immunoglobulins (IVIG), which are administered at intervals of 4-12 weeks. Determination of individual treatment intervals is challenging since existing clinical scores lack sensitivity to objectify small, partially fluctuating deficits in patients. End-of-dose phenomena described by patients, manifested by increased fatigue and worsening of (motor) symptoms, are currently difficult to detect. From a medical and socio-economic point of view, it is necessary to identify and validate new, more sensitive outcome measures for accurate mapping of disease progression and, thus, for interval finding. Digital health technologies such as wearables may be particularly useful for this purpose, as they record real-life data and consequently, in contrast to classic clinical 'snapshots', can continuously depict the disease course.

METHODS

In this prospective, observational, non-interventional, single-center, investigator-initiated study, CIDP patients treated with IVIG will be continuously monitored over a period of 6 months. Clinical scores and blood analyses will be assessed and collected during three visits (V1, V2, V3). Additionally, activity, sleep, and cardiac parameters will be recorded over the entire period using a wearable device. Further, patients' subjective disease development and quality of life will be recorded at various visits (read-outs). The usability of the smartwatch will be assessed at the end of the study.

PERSPECTIVE

The study aims to evaluate different digital measurements obtained with the smartwatch and blood-based analyses for monitoring disease activity and progress in CIDP patients. In conjunction, both means of monitoring might offer detailed insights into behavioral and biological patterns associated with treatment-related fluctuations such as end-of-dose phenomena.

TRIAL REGISTRATION

The study protocol was registered at ClinicalTrials.gov. Identifier: NCT05723848. Initially, the protocol was submitted prospectively on January 10, 2023. The trial was publicly released after formal improvements on February 13, 2023, after first patients were included according to the original protocol.

Intravenous Immunoglobulin Treatment Patterns and Outcomes in Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy: A US Claims Database Analysis

INTRODUCTION

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare progressive or relapsing inflammatory disease. Intravenous immunoglobulin (IVIG) is recommended as a first-line therapy. The aim of this study was to describe real-world treatment patterns and outcomes of patients with CIDP in the Define initiating IVIG treatment.

METHODS

This cohort study used health insurance claims data from the Merative MarketScan Research Databases (2008-2018). Adult patients (≥ 18 years old) with CIDP without prior immunoglobulin treatment were identified using International Statistical Classification of Diseases and Related Health Problems (ICD) codes, and patients subsequently initiating IVIG were included in the analysis. Real-world IVIG treatment patterns and treatment and safety outcomes (assessed via ICD codes) were described.

RESULTS

In total, 3975 patients (median age 58 years) with CIDP who initiated IVIG were identified. After the initial IVIG loading period, patients received IVIG at a median dosing interval of 21 days (quartile [Q]1, Q3: 7, 28), and continued treatment for a median of 129 days (Q1, Q3: 85, 271). After the 2-year follow-up period, 55% of patients had discontinued all IVIG treatment; more than one-half of these discontinuations occurred within 4 months. Diagnoses of impaired functional status were evident in more than 30% of patients at baseline, but at lower rates during follow-up. Rates of new-onset safety outcomes after IVIG treatment were low.

CONCLUSION

This real-world analysis of IVIG treatment patterns and treatment and safety outcomes of patients with CIDP who initiated IVIG highlights the unmet need for improved long-term management. Further research is needed to evaluate the use of functional status measures as endpoints for immunoglobulin treatment effectiveness.

Fatigue, depression, and product tolerability during long-term treatment with intravenous immunoglobulin (Gamunex® 10%) in patients with chronic inflammatory demyelinating polyneuropathy

INTRODUCTION/AIMS

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is characterized by progressive weakness and sensory loss, often affecting patient's ability to walk and perform activities of daily living independently. Furthermore, patients often report fatigue and depression which can affect their quality of life. These symptoms were assessed in CIDP patients receiving long-term intravenous immunoglobulin (IVIG) treatment.

METHODS

GAMEDIS was a multi-center, prospective, non-interventional study in adult CIDP patients treated with IVIG (10%) and followed for two years. Inflammatory Neuropathy Cause and Treatment (INCAT) disability score, Hughes Disability Scale (HDS), Fatigue Severity Scale (FSS), Beck Depression Inventory II (BDI), Short Form-36 health survey (SF-36) and Work Productivity and Activity Impairment Score Attributable to General Health (WPAI-GH) were assessed at baseline and quarterly. Dosing and treatment intervals, changes in outcome parameters, and adverse events (AEs) were analyzed.

RESULTS

148 evaluable patients were followed for a mean of 83.3 weeks. The mean maintenance IVIG dose was 0.9 g/kg/cycle (mean cycle interval 38 days). Disability and fatigue remained stable throughout the study. Mean INCAT score: 2.4 ± 1.8 at baseline and 2.5 ± 1.9 at study end. HDS: 74.3% healthy/minor symptoms at baseline and 71.6% at study end. Mean FSS: 4.2 ± 1.6 at baseline and 4.1 ± 1.7 at study end. All patients reported minimal/no depression at baseline and throughout. SF-36 and WPAI-GH scores remained stable. Fifteen patients (9.5%) experienced potentially treatment-related AEs. There were no AEs in 99.3% of infusions.

DISCUSSION

Long-term treatment of CIDP patients with IVIG 10% in real-world conditions maintained clinical stability on fatigue and depression over 96 weeks. This treatment was well-tolerated and safe.

Beneficial effects and safety of traditional Chinese medicine for chronic inflammatory demyelinating polyradiculoneuropathy: A case report and literature review

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an immune-mediated neuropathy. First-line treatments for CIDP include corticosteroids, intravenous immunoglobulin, and plasma exchange. However, the application is always limited by high costs, effectiveness, and adverse events. This study investigated a new potentially effective and safe therapeutic treatment to alleviate CIDP symptoms and improve the quality of life. In the present case, a 47-year-old rural woman presented with weakness and numbness of progressive extremities. She was diagnosed with CIDP based on abnormal cerebrospinal fluid and electromyography. The patient was treated with intravenous dexamethasone for 1 week and with Huangqi-Guizhi-Wuwu and Bu-Yang-Huan-Wu decoctions for 90 days. Surprisingly, after the treatment, the weakness and numbness were eliminated, and the quality of life improved. The varying INCAT, MRC, and BI scores also reflected the treatment effects. After 8 months of discharge, the symptoms did not relapse during the follow-up. We also searched “traditional Chinese medicine (TCM)” and “CIDP” in PubMed, EMBASE, the Web of Science, the Cochrane Library, the Chinese National Knowledge Infrastructure Databases, Wanfang Data, and the Chongqing Chinese Science and Technology Periodical Database. Finally, only ten studies were included in the literature review. Three studies were randomized controlled trials, and seven were case reports or case series. There were 419 CIDP patients, but all study sites were in China. Nine TCM formulas involving 44 herbs were reported, with Huang Qi (Astragalus membranaceus) being the most important herb. In conclusion, the case and literature demonstrated that TCM treatment might be a more effective, low-cost, and safe option for treating CIDP. Although these preliminary findings are promising, a larger sample size and higher-quality randomized clinical trials are urgently required to confirm our findings.

A Budget Impact Model of Maintenance Treatment of Chronic Inflammatory Demyelinating Polyneuropathy with IgPro20 (Hizentra) Relative to Intravenous Immunoglobulin in the United States

BACKGROUND

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare, progressive autoimmune disease causing peripheral nervous system dysfunction. Guidelines recommend immunoglobulin (IG) therapy as an immunomodulatory agent in CIDP. Drawbacks and unmet needs with intravenous immunoglobulin (IVIG) include adverse effects and wear-off effects, along with the burden of administration based on site of care. Subcutaneous administration of Hizentra, a subcutaneous immunoglobulin (SCIG) reduces patient burden by allowing self-administration outside the hospital setting and has fewer adverse events (AEs).

OBJECTIVE

We aimed to compare the expected cost of treatment and the budget impact of Hizentra compared with IVIG for maintenance treatment of CIDP in the United States.

METHODS

A decision tree model was developed to estimate the expected budget impact of maintenance treatment with Hizentra for US stakeholders. The model adopts primarily a US integrated delivery network perspective and, secondarily, a commercial perspective over a 1-year time horizon. Pharmacy costs were based on a payment mix of average sales price (73%), wholesale acquisition cost (2%), and average wholesale price (25%). Costs in the model reflect 2022 US dollars. In accordance with the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) guidelines and recommendations for budget impact modeling, no discounting was performed. The PATH clinical study of Hizentra maintenance in CIDP was used to determine clinical inputs for relapse rates at initial assessment (24 weeks) and at 52 weeks for Hizentra. The ICE clinical study of Gamunex maintenance in CIDP was the basis of relapse rates for Gamunex (and other IVIGs). Literature-based estimates were obtained for infusion costs by site of care, costs of IVIG infusion-related complications, and significant IVIG AE rates. Hizentra AE rates from the US Hizentra prescribing information were assessed but were not included in the model as the AEs in CIDP were mild, easily treated, and self-limited. Sensitivity analyses and scenario analyses were conducted to evaluate variations from the base case.

RESULTS

The model showed that a Hizentra starting dose of 0.2 g/kg is expected to result in annual cost savings of US$32,447 per patient compared with IVIG. For a hypothetical 25-million-member plan, the budget impact of a 10% market share shift from IVIG to Hizentra is expected to result in savings of US$2,296,235.

CONCLUSION

This analysis projects that Hizentra is likely associated with favorable economic benefit compared with IVIG in managing CIDP.

Treatment of CIDP

Chronic inflammatory demyelinating polyneuropathy is a disabling but treatable disorder. However, misdiagnosis is common, and it can be difficult to optimise its treatment. Various agents are used both for first and second line. First-line options are intravenous immunoglobulin, corticosteroids and plasma exchange. Second-line therapies may be introduced as steroid-sparing agents or as more potent escalation therapy. It is also important to consider symptomatic treatment of neuropathic pain and non-pharmacological interventions. We discuss the evidence for the various treatments and explain the practicalities of the different approaches. We also outline strategies for monitoring response and assessing the ongoing need for therapy.

Cost-minimisation analysis of plasma exchange versus IVIg in the treatment of autoimmune neurological conditions

Background

Plasma exchange (PLEX) is an effective treatment for antibody-mediated neurological disorders and has been shown to be equally efficacious to intravenous immunoglobulin (IVIg) with comparable adverse event profiles. IVIg has traditionally been the preferred treatment option due to its ease of use. However, advancing technology has allowed PLEX to be performed with a centrifugal system via peripheral access as opposed to central access via a membrane filter.

Methods

We prospectively collected data from a cohort of patients who underwent PLEX at the Wessex Neurological Centre, UK, to perform a cost-minimisation analysis comparing PLEX to IVIg, the standard of care, between May 2019 and May 2020. Data obtained included indication, admission type (inpatient, daycase or intensive care), access (peripheral or central), number of PLEX cycles, exchange volume, patient weight, complications and clinical outcomes. The cost of PLEX delivered in an outpatient setting for an average 80kg person was calculated and compared to the equivalent cost of delivering IVIg by means of a cost-minimization model.

Results

The provision of PLEX was roughly half as costly when compared to what it would have been for IVIg (£886 per exchange vs £1778 per infusion or £4432 per cycle of 5 exchanges vs £8890 per cycle of 5 infusions). Our cohort included a total of 44 patients who received a total of 357 PLEX exchanges during the 12-month period (the majority of which were in a daycase setting). We calculated an annual cost saving for PLEX over IVIg of £318,589. The robustness of this result was confirmed by a one-way deterministic sensitivity analysis, showing the cost-effectiveness of PLEX.

Conclusion

Our findings demonstrate that PLEX is more cost-effective than IVIg in this setting. Our study supports the economic case for development of plasma exchange centres in regional neurology units, a case made all the more relevant in the context of constrained supplies of IVIg.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08210-z.

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.

Immunomodulating Therapies in Acute Myocarditis and Recurrent/Acute Pericarditis

The field of inflammatory disease of the heart or "cardio-immunology" is rapidly evolving due to the wider use of non-invasive diagnostic tools able to detect and monitor myocardial inflammation. In acute myocarditis, recent data on the use of immunomodulating therapies have been reported both in the setting of systemic autoimmune disorders and in the setting of isolated forms, especially in patients with specific histology (e.g., eosinophilic myocarditis) or with an arrhythmicburden. A role for immunosuppressive therapies has been also shown in severe cases of coronavirus disease 2019 (COVID-19), a condition that can be associated with cardiac injury and acute myocarditis. Furthermore, ongoing clinical trials are assessing the role of high dosage methylprednisolone in the context of acute myocarditis complicated by heart failure or fulminant presentation or the role of anakinra to treat patients with acute myocarditis excluding patients with hemodynamically unstable conditions. In addition, the explosion of immune-mediated therapies in oncology has introduced new pathophysiological entities, such as immune-checkpoint inhibitor-associated myocarditis and new basic research models to understand the interaction between the cardiac and immune systems. Here we provide a broad overview of evolving areas in cardio-immunology. We summarize the use of new imaging tools in combination with endomyocardial biopsy and laboratory parameters such as high sensitivity troponin to monitor the response to immunomodulating therapies based on recent evidence and clinical experience. Concerning pericarditis, the normal composition of pericardial fluid has been recently elucidated, allowing to assess the actual presence of inflammation; indeed, normal pericardial fluid is rich in nucleated cells, protein, albumin, LDH, at levels consistent with inflammatory exudates in other biological fluids. Importantly, recent findings showed how innate immunity plays a pivotal role in the pathogenesis of recurrent pericarditis with raised C-reactive protein, with inflammasome and IL-1 overproduction as drivers for systemic inflammatory response. In the era of tailored medicine, anti-IL-1 agents such as anakinra and rilonacept have been demonstrated highly effective in patients with recurrent pericarditis associated with an inflammatory phenotype.

Contemporary challenges in the diagnosis and management of chronic inflammatory demyelinating polyneuropathy

INTRODUCTION

Despite extensive research, multiple inter-related diagnostic and management challenges remain for chronic inflammatory demyelinating polyneuropathy (CIDP).

AREAS COVERED

A literature review was performed on diagnosis and treatment in CIDP. The clinical features and disease course were evaluated. Investigative techniques, including electrophysiology, cerebrospinal fluid examination, neuropathology, imaging and neuroimmunology, were considered in relation to technical aspects, sensitivity, specificity, availability and cost. Available evidenced-based treatments and those with possible efficacy despite lack of evidence, were considered, as well as current methods for evaluation of treatment effects.

EXPERT OPINION

CIDP remains a clinical diagnosis, supported first and foremost by electrophysiology. Other investigative techniques have limited impact. Most patients with CIDP respond to available first-line treatments and immunosuppression may be efficacious in those who do not. Consideration of the natural history and of the high reported remission rate, of under-recognised associated disabling features, of treatment administration modalities and assessment methods, require enhanced attention.

CIDP: Current Treatments and Identification of Targets for Future Specific Therapeutic Intervention

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired immune-mediated inflammatory disorder of the peripheral nervous system. This clinically heterogeneous neurological disorder is closely related to Guillain–Barré syndrome and is considered the chronic counterpart of that acute disease. Currently available treatments are mostly empirical; they include corticosteroids, intravenous immunoglobulins, plasma exchange and chronic immunosuppressive agents, either alone or in combination. Recent advances in the understanding of the underlying pathogenic mechanisms in CIDP have brought a number of novel ways of possible intervention for use in CIDP. This review summarizes selected pre-clinical and clinical findings, highlights the importance of using adapted animal models to evaluate the efficacy of novel treatments, and proposes the outlines of future directions to ameliorate the conditions of patients with CIDP.

Clinical outcome of CIDP one year after start of treatment: a prospective cohort study

OBJECTIVE

To assess clinical outcome in treatment-naive patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

METHODS

We included adult treatment-naive patients participating in the prospective International CIDP Outcome Study (ICOS) that fulfilled the European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) diagnostic criteria for CIDP. Patients were grouped based on initial treatment with (1) intravenous immunoglobulin (IVIg), (2) corticosteroid monotherapy or (3) IVIg and corticosteroids (combination treatment). Outcome measures included the inflammatory Rasch-built overall disability scale (I-RODS), grip strength, and Medical Research Council (MRC) sum score. Treatment response, treatment status, remissions (improved and untreated), treatment changes, and residual symptoms or deficits were assessed at 1 year.

RESULTS

Forty patients were included of whom 18 (45%) initially received IVIg, 6 (15%) corticosteroids, and 16 (40%) combination treatment. Improvement on ≥ 1 of the outcome measures was seen in 31 (78%) patients. At 1 year, 19 (48%) patients were still treated and fourteen (36%) patients were in remission. Improvement was seen most frequently in patients started on IVIg (94%) and remission in those started on combination treatment (44%). Differences between groups did not reach statistical significance. Residual symptoms or deficits ranged from 25% for neuropathic pain to 96% for any sensory deficit.

CONCLUSIONS

Improvement was seen in most patients. One year after the start of treatment, more than half of the patients were untreated and around one-third in remission. Residual symptoms and deficits were common regardless of treatment.

Efficacy of rituximab treatment in chronic inflammatory demyelinating polyradiculoneuropathy: a systematic review and meta-analysis

BACKGROUND

Current standard treatment in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) has been proved effective, but it is poorly effective in refractory patients and unclear for anti-IgG4 antibody-associated CIDP. Rituximab is a B cell-depleting monoclonal antibody. It has been applied as one of the management strategies in CIDP, but its efficacy is unknown.

OBJECTIVE

To perform a systematic review and a meta-analysis of the efficacy of rituximab treatment in CIDP patients.

METHODS

Through searches in MEDLINE, PubMed, EMBASE, BIOSOS, Web of Science, and Cochrane library on March 31st, 2021, 15 studies were identified. Patients' characteristics, treatment regime and outcome measure were extracted.

RESULTS

Ninety-six patients in 15 studies were included. The pooled estimate of responsiveness was 75% (95% CI 72-78%). The standard mean difference (SMD) of Inflammatory Neuropathy Cause and Treatment (INCAT) disability score improvement was 1.7 (95% CI 1.0-2.3, p value < 0.0001) and the Medical Research Council (MRC) score for muscle power is 1.3 (95% CI - 2.6 to - 0.1, p value 0.04). All of the anti-IgG4 antibody-positive patients showed excellent responses to rituximab treatment.

CONCLUSION

Rituximab was effective in the treatment in CIDP patients, especially in anti-IgG4 antibody-positive patients. Randomized clinical trials are needed to determine the effectiveness and safety of rituximab in CIDP patients.

Borrelia burgdorferi sensu lato seroconversion after intravenous immunoglobulin treatment: A cohort study

Objective

Intravenous immunoglobulin (IVIg) consists of pooled donor immunoglobulins (IgG), possibly including anti‐Borrelia burgdorferi (Bbsl) antibodies. Apparent IVIg‐related Bbsl seroconversion could lead to incorrect diagnosis of Lyme borreliosis. This cohort study was designed to determine how often IVIg treatment leads to apparent Bbsl seroconversion and whether antibodies disappear post‐treatment.

Methods

Sera from chronic inflammatory demyelinating polyneuropathy (CIDP) and myositis patients were analyzed, drawn pre‐treatment and 6–12 weeks after the start of IVIg. In patients with apparent seroconversion, follow‐up samples after treatment withdrawal were analyzed, if available. Patients treated with corticosteroids were included as controls. A two‐tier protocol was used for serological testing consisting of the C6 Lyme ELISA (Oxford Immunotec) and confirmation by immunoglobulin M (IgM) and immunoglobulin G (IgG) immunoblot (Mikrogen^®).

Results

We included 61 patients: 51 patients were treated with IVIg and 10 with dexamethasone. Of the patients treated with IVIg, 42 had CIDP (82%) and were treated with Nanogam^® (Sanquin Plasma Products). Nine patients had myositis (18%) and were treated with Privigen^® (CSL Behring). Anti‐Bbsl IgG seroprevalence pre‐treatment was 3% (2/61). Apparent seroconversion during IVIg treatment occurred in 39% (20/51) of patients, all treated with Nanogam. Post‐treatment seroreversion occurred in 92% (12/13) of patients with available follow‐up samples; in 78% (7/9) seroreversion was observed within 3 months.

Conclusions

Transient presence of anti‐Bbsl IgG antibodies after IVIg is regularly observed. This effect appears to be dependent on the IVIg brand, probably reflecting variation in Bbsl exposure of plasma donors. Lyme borreliosis serological testing during, and weeks to months after, IVIg is therefore of limited utility.

Evaluation of the risk factors predicting thrombotic complications associated with intravenous immunoglobulin therapy in neuroimmunological diseases

Intravenous immunoglobulin (IVIg) therapy is increasingly used for various conditions that include neuroimmunological disorders, such as chronic inflammatory demyelinating polyneuropathy, Guillain-Barré syndrome, myasthenia gravis, and myositis. Although IVIg therapy is considered a relatively safe treatment, previous studies have reported thrombotic complications associated with IVIg (TCI). The precise mechanisms and associated risk factors have not been fully elucidated to date. Three of our patients experienced TCI. Although immobility is one of the most common risk factors for venous thrombosis, all three patients could walk without assistance; their modified Rankin Scale (mRS) scores were 2. We assessed the clinical characteristics of these patients and compared their data with that of 65 patients who received IVIg from the years 2000 to 2019 without experiencing TCI to identify associated risk factors. The frequency of TCI among patients with neuroimmunological disorders at our hospital was 4.4% (3/68 patients). There were no significant differences between the patients with and without TCI regarding their mean age (69.7 vs 58.0 years, p = 0.244), percentage of females (66.7% vs 45.6%, p = 0.588), mean body mass index (22.67 vs 22.16, p = 0.878), mean mRS score (2.22 vs 2.00, p = 0.658), and use of oral prednisolone (66.7% vs 13.8%, p = 0.0658). Interestingly, the D-dimer levels of two of the patients with TCI were not elevated before treatment. Sixteen patients received anticoagulant therapy during IVIg treatment, and none suffered from TCI. As our analysis suggested, it might be important to monitor D-dimer levels before and after IVIg to help prevent and detect TCI.

Prognostic value of neurofilament light chain in chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyneuropathy is a neuroinflammatory disorder with considerable variation in clinical phenotype, disease progression and therapy response among patients. Recently, paranodal antibodies associated with poor response to intravenous immunoglobulin therapy and more aggressive disease course have been described in small subsets of patients, but reliable serum-based prognostic biomarkers are not yet available for the general population. In current retrospective longitudinal study, we utilized logistic regression models to investigate the associations of serum neurofilament light chain levels with 1-year disease progression and therapy response during follow-up in chronic inflammatory demyelinating polyneuropathy. One-year disease progression was defined as a decrease of four or more points (the minimal clinically important difference) on an 80-point Medical Research Council sum-score scale 1 year after sampling. Patients who, compared to treatment received at time of sampling, required therapy switch during follow-up due to insufficient effect were classified as non-responders. Serum neurofilament light chain was measured by electrochemiluminescence assay in clinical residual serum samples of 76 patients diagnosed with probable (13 patients) or definite (63 patients) chronic inflammatory demyelinating polyneuropathy according to European Federation of Neurological Societies/Peripheral Nerve Society diagnostic criteria. Eleven (15%) patients were female, and the mean (standard deviation) cohort age was 61.5 (11.7) years. In both univariate and multivariable (including demographics) models, elevated serum neurofilament light chain harboured increased odds for 1-year disease progression (respectively odds ratio, 1.049; 95% confidence interval, 1.022-1.084 and odds ratio, 1.097; 95% confidence interval, 1.045-1.169; both P = 0.001). Patients with levels above the median cohort neurofilament light chain level (28.3 pg/ml) had largely increased odds of 1-year disease progression (univariate: odds ratio, 5.597; 95% confidence interval, 1.590-26.457; P = 0.01; multivariable: odds ratio, 6.572; 95% confidence interval, 1.495-39.702; P = 0.02) and of insufficient treatment response (univariate: odds ratio, 4.800; 95% confidence interval, 1.622-16.442; P = 0.007; multivariable: odds ratio, 6.441; 95% confidence interval, 1.749-29.357; P = 0.009). In a combined approach analysis, patients with levels above median cohort serum neurofilament light chain level reported strongly increased odds of demonstrating 1-year disease progression and/or therapy non-response during follow-up (univariate: odds ratio, 6.337; 95% confidence interval, 2.276-19.469; P < 0.001; multivariable: odds ratio, 10.138; 95% confidence interval, 2.801-46.404; P = 0.001). These results show that in various logistic regression models, serum neurofilament light chain was associated with both 1-year disease progression and therapy response during follow-up in chronic inflammatory demyelinating polyneuropathy. Hence, our findings warrant further prospective research regarding the value of neurofilament light chain as potential prognostic biomarker in chronic inflammatory demyelinating polyneuropathy.

Intravenous Immunoglobulin Therapy in Patients With Painful Idiopathic Small Fiber Neuropathy

Objective

This is the first double-blind randomized controlled trial evaluating the efficacy and safety of IV immunoglobulin (IVIG) vs placebo in patients with idiopathic small fiber neuropathy (I-SFN).

Methods

Between July 2016 and November 2018, 60 Dutch patients with skin biopsy–proven I-SFN randomly received a starting dose of IVIG (2 g/kg body weight) or matching placebo (0.9% saline). Subsequently, 3 additional infusions of IVIG (1 g/kg) or placebo were administered at 3-week intervals. The primary outcome was a 1-point change in Pain Intensity Numerical Rating Scale score at 12 weeks compared to baseline.

Results

Thirty patients received IVIG, and 30 received placebo. In both groups, 29 patients completed the trial. In 40% of patients receiving IVIG, the mean average pain was decreased by at least 1 point compared to 30% of the patients receiving placebo (p = 0.588, odds ratio 1.56, 95% confidence interval 0.53–4.53). No significant differences were found on any of the other prespecified outcomes, including general well-being, autonomic symptoms, and overall functioning and disability.

Conclusions

This randomized controlled trial showed that IVIG treatment had no significant effect on pain in patients with painful I-SFN.

Trial Registration Information

ClinicalTrials.gov Identifier: NCT02637700, EudraCT 2015-002624-31.

Classification of Evidence

This study provides Class I evidence that for patients with painful I-SFN, IVIG did not significantly reduce pain compared to placebo.

Individualizing Therapy in CIDP: A Mini-Review Comparing the Pharmacokinetics of Ig With SCIg and IVIg

Immunoglobulin (Ig) therapy is a first-line treatment for CIDP, which can be administered intravenously (IVIg) or subcutaneously (SCIg) and is often required long term. The differences between these modes of administration and how they can affect dosing strategies and treatment optimization need to be understood. In general, the efficacy of IVIg and SCIg appear comparable in CIDP, but SCIg may offer some safety and quality of life advantages to some patients. The differences in pharmacokinetic (PK) profile and infusion regimens account for many of the differences between IVIg and SCIg. IVIg is administered as a large bolus every 3–4 weeks resulting in cyclic fluctuations in Ig concentration that have been linked to systemic adverse events (AEs) (potentially caused by high Ig levels) and end of dose “wear-off” effects (potentially caused by low Ig concentration). SCIg is administered as a smaller weekly, or twice weekly, volume resulting in near steady-state Ig levels that have been linked to continuously maintained function and reduced systemic AEs, but an increase in local reactions at the infusion site. The reduced frequency of systemic AEs observed with SCIg is likely related to the avoidance of high Ig concentrations. Some small studies in immune-mediated neuropathies have focused on serum Ig data to evaluate its potential use as a biomarker to aid clinical decision-making. Analyzing dose data may help understand how establishing and monitoring patients' Ig concentration could aid dose optimization and the transition from IVIg to SCIg therapy.

Intravenous immunoglobulin and intravenous methylprednisolone as optimal induction treatment in chronic inflammatory demyelinating polyradiculoneuropathy: protocol of an international, randomised, double-blind, placebo-controlled trial (OPTIC)

Background

International guidelines recommend either intravenous immunoglobulin (IVIg) or corticosteroids as first-line treatment for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). IVIg treatment usually leads to rapid improvement and is generally safe, but does not seem to lead to long-term remissions. Corticosteroids act more slowly and are associated with more side effects, but may induce long-term remissions. The hypothesis of this study is that combined IVIg and corticosteroid induction treatment will lead to more frequent long-term remissions than IVIg treatment alone.

Methods

An international, randomised, double-blind, placebo-controlled trial, in adults with ‘probable’ or ‘definite’ CIDP according to the EFNS/PNS 2010 criteria. Three groups of patients are included: (1) treatment naïve, (2) known CIDP patients with a relapse after > 1 year without treatment, and (3) patients with CIDP who improved within 3 months after a single course of IVIg, who subsequently deteriorate at any interval without having received additional treatment. Patients are randomised to receive 7 courses of IVIg and 1000 mg intravenous methylprednisolone (IVMP) (in sodium chloride 0.9%) or IVIg and placebo (sodium chloride 0.9%), every 3 weeks for 18 weeks. IVIg treatment consists of a loading dose of 2 g/kg (over 3–5 days) followed by 6 courses of IVIg 1/g/kg (over 1–2 days). The primary outcome is remission at 1 year, defined as improvement in disability from baseline, sustained between week 18 and week 52 without further treatment. Secondary outcomes include changes in disability, impairment, pain, fatigue, quality of life, care use and costs and (long-term) safety.

Discussion

In case of superiority of the combined treatment, patients will experience the advantages of two proven efficacious treatments, namely rapid improvement due to IVIg and long-term remission due to corticosteroids. Long-term remission would reduce the need for maintenance IVIg treatment and may decrease health care costs. Additionally, we expect that the combined treatment leads to a higher proportion of patients with improvement as some patients who do not respond to IVIg will respond to corticosteroids. Risks of short and long-term additional adverse events of the combined treatment need to be assessed.

Trial registration

ISRCTN registry ISRCTN15893334. Prospectively registered on 12 February 2018.

Diagnostic challenges in chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) consists of a spectrum of autoimmune diseases of the peripheral nerves, causing weakness and sensory symptoms. Diagnosis often is challenging, because of the heterogeneous presentation and both mis- and underdiagnosis are common. Nerve conduction study (NCS) abnormalities suggestive of demyelination are mandatory to fulfil the diagnostic criteria. On the one hand, performance and interpretation of NCS can be difficult and none of these demyelinating findings are specific for CIDP. On the other hand, not all patients will be detected despite the relatively high sensitivity of NCS abnormalities. The electrodiagnostic criteria can be supplemented with additional diagnostic tests such as CSF examination, MRI, nerve biopsy, and somatosensory evoked potentials. However, the evidence for each of these additional diagnostic tests is limited. Studies are often small without the use of a clinically relevant control group. None of the findings are specific for CIDP, meaning that the results of the diagnostic tests should be carefully interpreted. In this update we will discuss the pitfalls in diagnosing CIDP and the value of newly introduced diagnostic tests such as nerve ultrasound and testing for autoantibodies, which are not yet part of the guidelines.

Economic evaluation of subcutaneous versus intravenous immunoglobulin therapy in chronic inflammatory demyelinating polyneuropathy: a real-life study

OBJECTIVES

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired peripheral neuropathy of immunological origin with a clinical presentation and course that are extremely variable. The therapeutic approach generally includes corticosteroid drugs, intravenous immunoglobulins (IVIGs) or plasmapheresis alone or in combination as first line therapy, and immunosuppressants. In 2014 the Italian regulatory agency included subcutaneous immunoglobulins (SCIGs) in the list of off-label drugs reimbursed by the national health service. Our aim is to compare costs and outcomes of IVIG versus SCIG therapy.

METHODS

Patients medical records and therapeutic plans were retrospectively analysed to collect data on IVIG treatments 1 year before the switch to SCIG, and after 1 year of treatment with SCIG. A budget impact analysis was conducted through resource identification and quantification, and healthcare and non-health care costs evaluation.

RESULTS

13 of 34 patients affected by CIDP who were referred to our neurophysiopathological unit and treated with IVIG were switched to home-based SCIG. After 1 year of receiving SCIG, 12 patients remained neurologically stable and reported good outcomes. Considering the cost of IVIG (€30.97/g) and adding to this the direct and indirect healthcare costs, the total cost of IVIG treatment for the 12 patients in a year was €371 417.06, compared with the cost of SCIG (€51.57/g) for a total annual cost of €631 745.16, not including indirect costs.

CONCLUSIONS

We observe a higher cost for SCIG treatment versus IVIG, which is not in line with data in the literature. However, SCIGs offer some important safety benefits and improvements in patient quality of life.

Diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy in clinical practice: A survey among Dutch neurologists

The diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is often a challenge. The clinical presentation is diverse, accurate biomarkers are lacking, and the best strategy to initiate and maintain treatment is unclear. The aim of this study was to determine how neurologists diagnose and treat CIDP. We conducted a cross‐sectional survey on diagnostic and treatment practices among Dutch neurologists involved in the clinical care of CIDP patients. Forty‐four neurologists completed the survey (44/71; 62%). The respondents indicated to use the European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) 2010 CIDP guideline for the diagnosis in 77% and for treatment in 50%. Only 57% of respondents indicated that the presence of demyelinating electrophysiological findings was mandatory to confirm the diagnosis of CIDP. Most neurologists used intravenous immunoglobulins (IVIg) as first choice treatment, but the indications to start, optimize, or withdraw IVIg, and the use of other immune‐modulatory therapies varied. University‐affiliated respondents used the EFNS/PNS 2010 diagnostic criteria, nerve imaging tools, and immunosuppressive drugs more often. Despite the existence of an international guideline, there is considerable variation among neurologists in the strategies employed to diagnose and treat CIDP. More specific recommendations regarding: (a) the minimal set of electrophysiological requirements to diagnose CIDP, (b) the possible added value of nerve imaging, especially in patients not meeting the electrodiagnostic criteria, (c) the most relevant serological examinations, and (d) the clear treatment advice, in the new EFNS/PNS guideline, would likely support its implementation in clinical practice.

Immunoadsorption and Plasma Exchange in Seropositive and Seronegative Immune-Mediated Neuropathies

The inflammatory neuropathies are disabling conditions with diverse immunological mechanisms. In some, a pathogenic role for immunoglobulin G (IgG)-class autoantibodies is increasingly appreciated, and immunoadsorption (IA) may therefore be a useful therapeutic option. We reviewed the use of and response to IA or plasma exchange (PLEx) in a cohort of 41 patients with nodal/paranodal antibodies identified from a total of 573 individuals with suspected inflammatory neuropathies during the course of routine diagnostic testing (PNAb cohort). 20 patients had been treated with PLEx and 4 with IA. Following a global but subjective evaluation by their treating clinicians, none of these patients were judged to have had a good response to either of these treatment modalities. Sequential serology of one PNAb+ case suggests prolonged suppression of antibody levels with frequent apheresis cycles or adjuvant therapies, may be required for effective treatment. We further retrospectively evaluated the serological status of 40 patients with either Guillain-Barré syndrome (GBS) or chronic inflammatory demyelinating polyneuropathy (CIDP), and a control group of 20 patients with clinically-isolated syndrome/multiple sclerosis (CIS/MS), who had all been treated with IgG-depleting IA (IA cohort). 32 of these patients (8/20 with CIDP, 13/20 with GBS, 11/20 with MS) were judged responsive to apheresis despite none of the serum samples from this cohort testing positive for IgG antibodies against glycolipids or nodal/paranodal cell-adhesion molecules. Although negative on antigen specific assays, three patients' pre-treatment sera and eluates were reactive against different components of myelinating co-cultures. In summary, preliminary evidence suggests that GBS/CIDP patients without detectable IgG antibodies on routine diagnostic tests may nevertheless benefit from IA, and that an unbiased screening approach using myelinating co-cultures may assist in the detection of further autoantibodies which remain to be identified in such patients.

Combined intravenous immunoglobulin and methylprednisolone as induction treatment in chronic inflammatory demyelinating polyneuropathy (OPTIC protocol): a prospective pilot study

BACKGROUND AND PURPOSE

We hypothesized that combining intravenous immunoglobulin (IVIg) and intravenous methylprednisolone (IVMP) leads to more frequent remission compared with IVIg alone while maintaining the fast efficacy of IVIg. In this uncontrolled pilot study, we evaluated remission, rate of improvement and safety in patients with chronic inflammatory demyelinating polyradiculoneuropathy receiving induction treatment with combined IVIg and IVMP.

METHODS

Consecutive treatment-naive patients with chronic inflammatory demyelinating polyradiculoneuropathy were treated with IVIg infusions, consisting of a 2 g/kg loading dose and 1 g/kg maintenance treatment every 3 weeks, combined with 3-weekly 1-g IVMP infusions, for a total of 18 weeks. The cumulative steroid dose was 7 g. Primary outcome was remission at 1 year in patients who completed the treatment schedule. Remission was defined as improvement at 18 weeks without the need for further immune treatment between end of the treatment schedule and 1-year follow-up. Improvement was defined as a minimal clinically important difference on the Inflammatory Rasch-Built Overall Disability Scale and/or an increase of ≥8 kPa in grip strength between baseline and week 18.

RESULTS

A total of 20 patients were included; 17 completed the treatment schedule. A total of 13 (76%) of these patients improved at 18 weeks after start of treatment and 10 (59%) patients were in remission at 1 year. Serious adverse events were found in four patients.

CONCLUSIONS

Short-term combined induction treatment with IVIg and IVMP induced remission in almost 60% of patients who completed the treatment schedule. Combined induction therapy was generally well tolerated. A randomized controlled trial is currently running to confirm efficacy and safety of IVMP as add-on treatment to IVIg.

Are the treatments for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) effective and safe? - A Cochrane Overview summary with commentary

BACKGROUND

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a potentially disabling health condition.

OBJECTIVE

To assess the effects of different pharmacological interventions used in CIPD.

METHODS

To summarize and to discuss the rehabilitation perspective on the published Cochrane Overview "Treatments for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP): an overviewof systematic reviews" by Anne Louise Oaklander, et al., representing the Cochrane Neuromuscular Group.

RESULTS

Five CSRs and 23 RCTs, reporting data on corticosteroids, plasma exchange and intravenous immunoglobulin, were considered in the overview.

CONCLUSIONS

High quality trials investigating the combined effectiveness of drugs and exercise using ICF based outcomes should be encouraged.

Efficacy and Safety of Octagam® in Patients With Chronic Inflammatory Demyelinating Polyneuropathy

Introduction

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a debilitating autoimmune neuropathy that is treated with intravenous immunoglobulin (IVIG). The aim of this retrospective study was to investigate the efficacy and safety of the sucrose-free IVIG Octagam® (Octapharma AG, Lachen, Switzerland) in patients with CIDP.

Methods

Data from 47 patients who received at least one dose of Octagam were collected from the records of 11 centres in France. Efficacy was assessed using Overall Neuropathy Limitation Scale (ONLS). Safety was evaluated using adverse event rates.

Results

Data from 24 patients who were IVIG naïve (n = 11) or had stopped IVIG ≥ 12 weeks before   initiation of Octagam therapy (washout group; n  = 13) were included in the efficacy analysis. At 4 months post-initiation of Octagam treatment, 41.7% of patients had improved their functional status (decrease of ≥ 1 ONLS score) with a significant change   in the ONLS score from baseline (– 0.42; p = 0.04; signed test). Functional status was reduced in only two patients: one patient in the IVIG-naïve group and one patient in the IVIG-washout group. All 47 patients were included in the safety analysis, which showed that Octagam was well tolerated, with a frequency of 0.04 adverse events per Octagam course. The most common adverse drug reaction was headache.

Conclusions

These real-life results are consistent with the efficacy and safety of IVIG reported in randomised controlled studies. A long-term prospective study of Octagam in patients with CIDP is warranted.

Funding

Octapharma, France SAS.

FTY720 controls disease severity and attenuates sciatic nerve damage in chronic experimental autoimmune neuritis

Background

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an autoimmune-mediated inflammatory disease of the peripheral nervous system characterized by a response directed against certain myelin proteins and for which therapies are limited. Previous studies have suggested a beneficial role of FTY720, a sphingosine 1-phosphate (S1P) receptor agonist, known to deplete lymphocytes from the peripheral blood by sequestering them into lymph nodes, in the treatment of experimental autoimmune neuritis (EAN). Therefore, we investigated whether FTY720 is also beneficial in chronic experimental autoimmune neuritis (c-EAN), a recently developed rat model mimicking human CIDP.

Methods

c-EAN was induced in Lewis rats by immunization with S-palm P0(180–199) peptide. Rats were treated with FTY720 (1 mg/kg) or vehicle intraperitoneally once daily from the onset of clinical signs for 18 days; clinical signs were assessed daily until 60 days post-immunization (dpi). Electrophysiological and histological features were examined at different time points. We also evaluated the serum levels of different pro- and anti-inflammatory cytokines by ELISA or flow cytometry at 18, 40, and 60 dpi.

Results

Our data demonstrate that FTY720 decreased the severity and abolished the chronicity of the disease in c-EAN rats. Therapeutic FTY720 treatment reversed electrophysiological and histological anomalies, suggesting that myelinated fibers were subsequently preserved, it inhibited macrophage and IL-17⁺ cell infiltration in PNS, and it significantly reduced circulating pro-inflammatory cytokines.

Conclusions

FTY720 treatment has beneficial effects on c-EAN, a new animal model mimicking human CIDP. We have shown that FTY720 is an effective immunomodulatory agent, improving the disease course of c-EAN, preserving the myelinated fibers, attenuating the axonal degeneration, and decreasing the number of infiltrated inflammatory cells in peripheral nerves. These data confirm the interest of testing FTY720 or molecules targeting S1P in human peripheral neuropathies.

Electronic supplementary material

The online version of this article (10.1186/s12974-019-1441-4) contains supplementary material, which is available to authorized users.

Corticosteroids in chronic inflammatory demyelinating polyneuropathy : A retrospective, multicentre study, comparing efficacy and safety of daily prednisolone, pulsed dexamethasone, and pulsed intravenous methylprednisolone

Background

Chronic inflammatory demyelinating polyneuropathy (CIDP) can be treated with corticosteroids or intravenous immunoglobulins. Various corticosteroid regimens are currently used in CIDP, but it is unknown whether they are equally efficacious. In this retrospective study, we compared efficacy and safety of three corticosteroid regimens in CIDP patients.

Methods

We included treatment naïve patients that fulfilled the EFNS/PNS criteria for CIDP. Patients were treated with corticosteroids according to the local protocol of three CIDP expertise centres. Corticosteroid regimens consisted of daily oral prednisolone, pulsed oral dexamethasone, or pulsed intravenous methylprednisolone. Outcomes were number of responders to treatment, remission rate of treatment responders, overall probability of 5-year remission, and the occurrence of adverse events.

Results

A total of 125 patients were included. Sixty-seven (54%) patients received daily prednisone or prednisolone, 37 (30%) pulsed dexamethasone, and 21 (17%) pulsed intravenous methylprednisolone. Overall, 60% (95% CI 51–69%) responded to corticosteroids, with no significant difference between the three treatment regimens (p = 0.56). From the 75 responders, 61% (95% CI 50–73%) remained in remission, during a median follow-up of 55 months (range 1–197 months). The probability of responders reaching 5-year remission was 55% (95% Cl 44–70%), with no difference between the three groups. Adverse events leading to a change in treatment occurred in ten patients (8%). Two patients had a serious adverse event.

Conclusion

Corticosteroids lead to improvement in 60% of patients and to remission in 61% of treatment responders. There were no differences between treatment modalities in terms of efficacy and safety.

A randomised, multi-centre phase III study of 3 different doses of intravenous immunoglobulin 10% in patients with chronic inflammatory demyelinating polyradiculoneuropathy (ProCID trial): Study design and protocol

Patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) show varying degrees of response to intravenous immunoglobulin (IVIg) therapy. This randomised phase III study in patients with CIDP (ProCID trial) will compare the efficacy and safety of 3 different doses (0.5, 1.0, and 2.0 g/kg) of IVIg 10% (panzyga) administered every 3 weeks for 24 weeks. The primary efficacy endpoint is the rate of treatment response, defined as a decrease in adjusted inflammatory neuropathy cause and treatment disability score of ≥1 point, in the IVIg 1.0 g/kg arm at week 24. Patients with definite or probable CIDP according to European Federation of Neurological Sciences/Peripheral Nerve Society criteria with IVIg or corticosteroid dependency and active disease are eligible. All potentially eligible patients will undergo IVIg or corticosteroid dose reduction (washout phase) over ≤12 weeks or until deterioration of CIDP (active disease). Patients with deterioration during the washout phase will be randomised to receive study treatment during a dose‐evaluation phase starting with a loading dose of IVIg 2.0 g/kg followed by maintenance treatment with IVIg 0.5, 1.0, or 2.0 g/kg every 3 weeks. Rescue medication (2 doses of IVIg 2.0 g/kg given 3 weeks apart) will be administered to patients in the IVIg 0.5 and 1.0 g/kg groups who deteriorate after week 3 and before week 18 or who do not improve at week 6. Safety, tolerability and quality of life will be assessed. The ProCID study will provide new information on the best maintenance dose of IVIg for patients with CIDP.

Octagam® for chronic inflammatory demyelinating polyneuropathy: results from three observational studies

Aim:

To present data from three studies of a Post-Authorization Safety Surveillance (PASS) program for the subset of patients receiving Octagam^® 5% or 10% for chronic inflammatory demyelinating polyneuropathy (CIDP).

Methods:

Data on patients with CIDP treated with Octagam were analyzed to assess its safety and tolerability.

Results:

Of 2314 patients included in the studies, 58 patients (mean age: 64.6 years) received Octagam for CIDP, mean dose of which was 0.8 g/kg bodyweight/course. 81% of observations for clinical appearance since last observation were assessed as stable and 16.6% showed an improved clinical appearance with treatment. Adverse drug reactions were rare (<0.7% of infusions).

Conclusion:

Octagam was effective and well-tolerated in patients with CIDP.

An idiopathic thrombocytopenic purpura with polyneuropathy

Concurrent association of idiopathic thrombocytopenic purpura (ITP) and peripheral neuropathy is a rare condition. There are only few case reports published concerning peripheral neuropathy with ITP. One of the etiopathogenetic mechanisms proposed is intraneural hemorrhage, but the pathogenesis is not fully understood. Autoimmune nature with common antibodies to the platelets and the nerve´s myelin sheath should also be considered. Here we describe a 47-year-old woman, with a family history of autoimmune diseases. She was diagnosed 2 years ago with ITP and later developed a chronic combined inflammatory demyelinating polyneuropathy. Treatment with high-dose steroids was initiated with a poor response. The patient showed a clear improvement in platelet count and in the peripheral neuropathy symptoms when treatment with intravenous immunoglobulin was administered. Common etiologic mechanism of the two diseases should be considered, both, because of the simultaneous time of development and a similar response to intravenous immunoglobulin treatment.

New Insights into Pericarditis: Mechanisms of Injury and Therapeutic Targets

PURPOSE OF REVIEW

This review article aims to provide a contemporary insight into the pathophysiological mechanisms of and therapeutic targets for pericarditis, drawing distinction between autoinflammatory and autoimmune pericarditis.

RECENT FINDINGS

Recent research has focused on the distinction between autoinflammatory and autoimmune pericarditis. In autoinflammatory pericarditis, viruses can activate the sensor molecule of the inflammasome, which results in downstream release of cytokines, such as interleukin-1, that recruit neutrophils and macrophages to the site of injury. Conversely, in autoimmune pericarditis, a type I interferon signature predominates, and pericardial manifestations coincide with the severity of the underlying systemic autoimmune disease. In addition, autoimmune pericarditis can also develop after cardiac injury syndromes. With either type of pericarditis, imaging can help stage the inflammatory state. Prominent pericardial delayed hyperenhancement on magnetic resonance imaging suggests ongoing inflammation whereas calcium on computed tomography suggests a completed inflammatory cascade. In patients with ongoing pericarditis, treatments that converge on the inflammasome, such as colchicine and anakinra, have proved effective in recurrent autoinflammatory pericarditis, though further clinical trials with anakinra are warranted. An improved understanding of the pathophysiological mechanisms of pericarditis helps unravel effective therapeutic targets for this condition.

Corticosteroids for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a progressive or relapsing and remitting paralysing illness, probably due to an autoimmune response, which should benefit from corticosteroid treatment. Non-randomised studies suggest that corticosteroids are beneficial. Two commonly used corticosteroids are prednisone and prednisolone. Both are usually given as oral tablets. Prednisone is converted into prednisolone in the liver so that the effect of the two drugs is usually the same. Another corticosteroid, dexamethasone, is more potent and is used in smaller doses. The review was first published in 2001 and last updated in 2015; we undertook this update to identify any new evidence.

OBJECTIVES

To assess the effects of corticosteroid treatment for CIDP compared to placebo or no treatment, and to compare the effects of different corticosteroid regimens.

SEARCH METHODS

On 8 November 2016, we searched the Cochrane Neuromuscular Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE, and Embase for randomised trials of corticosteroids for CIDP. We searched clinical trials registries for ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-RCTs of treatment with any corticosteroid or adrenocorticotrophic hormone for CIDP, diagnosed by an internationally accepted definition.

DATA COLLECTION AND ANALYSIS

Two authors extracted data from included studies and assessed the risk of bias independently. The intended primary outcome was change in disability, with change in impairment after 12 weeks and side effects as secondary outcomes. We assessed strength of evidence using the GRADE approach.

MAIN RESULTS

One non-blinded RCT comparing prednisone with no treatment in 35 eligible participants did not measure the primary outcome for this systematic review. The trial had a high risk of bias. Neuropathy Impairment Scale scores after 12 weeks improved in 12 of 19 participants randomised to prednisone, compared with five of 16 participants randomised to no treatment (risk ratio (RR) for improvement 2.02 (95% confidence interval (CI) 0.90 to 4.52; very low-quality evidence). The trial did not report side effects in detail, but one prednisone-treated participant died.A double-blind RCT comparing daily standard-dose oral prednisolone with monthly high-dose oral dexamethasone in 40 participants reported none of the prespecified outcomes for this review. The trial had a low risk of bias, but the quality of evidence was limited as it came from a single small study. There was little or no difference in number of participants who achieved remission (RR 1.11; 95% CI 0.50 to 2.45 in favour of monthly dexamethasone; moderate-quality evidence), or change in disability or impairment after one year (low-quality evidence). Change of grip strength or Medical Research Council (MRC) scores demonstrated little or no difference between groups (moderate-quality to low-quality evidence). Eight of 16 people in the prednisolone group and seven of 24 people in the dexamethasone group deteriorated. Side effects were similar with each regimen, except that sleeplessness was less common with monthly dexamethasone (low-quality evidence) as was moon facies (moon-shaped appearance of the face) (moderate-quality evidence).Experience from large non-randomised studies suggests that corticosteroids are beneficial, but long-term use causes serious side effects.

AUTHORS' CONCLUSIONS

We are very uncertain about the effects of oral prednisone compared with no treatment, because the quality of evidence from the only RCT that exists is very low. Nevertheless, corticosteroids are commonly used in practice, supported by very low-quality evidence from observational studies. We also know from observational studies that corticosteroids carry the long-term risk of serious side effects. The efficacy of high-dose monthly oral dexamethasone is probably little different from that of daily standard-dose oral prednisolone. Most side effects occurred with similar frequencies in both groups, but with high-dose monthly oral dexamethasone moon facies is probably less common and sleeplessness may be less common than with oral prednisolone. We need further research to identify factors that predict response.

Antibodies against peripheral nerve antigens in chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a heterogeneous disease in which diverse autoantibodies have been described but systematic screening has never been performed. Detection of CIDP-specific antibodies may be clinically useful. We developed a screening protocol to uncover novel reactivities in CIDP. Sixty-five CIDP patients and 28 controls were included in our study. Three patients (4.6%) had antibodies against neurofascin 155, four (6.2%) against contactin-1 and one (1.5%) against the contactin-1/contactin-associated protein-1 complex. Eleven (18.6%) patients showed anti-ganglioside antibodies, and one (1.6%) antibodies against peripheral myelin protein 2. No antibodies against myelin protein zero, contactin-2/contactin-associated protein-2 complex, neuronal cell adhesion molecule, gliomedin or the voltage-gated sodium channel were detected. In IgG experiments, three patients (5.3%) showed a weak reactivity against motor neurons; 14 (24.6%) reacted against DRG neurons, four of them strongly (7.0%), and seven (12.3%) reacted against Schwann cells, three of them strongly (5.3%). In IgM experiments, six patients (10.7%) reacted against DRG neurons, while three (5.4%) reacted against Schwann cells. However, results were not statistically significant when compared to controls. Immunoprecipitation experiments identified CD9 and L1CAM as potential antigens, but reactivity could not be confirmed with cell-based assays. In summary, we describe a diverse autoantibody repertoire in CIDP patients, reinforcing the hypothesis of CIDP’s pathophysiological heterogeneity.

Early predictive factors of disability in CIDP

The objective of this study was to identify early clinical, biochemical and electrophysiological prognostic factors of disability in CIDP. We evaluated a dataset from 60 CIDP patients that included sex, age of onset, type of onset, phenotype, disease duration, response to treatment, disability at the time of diagnosis assessed using the modified Rankin Scale (baseline mRS), cerebrospinal fluid protein levels and electrophysiological data. All patients had clinical assessment of disability through the mRS within the last 6 months (last mRS) before enrollment in the study. Stepwise forward logistic regression model was applied to evaluate the impact of clinical, biochemical and electrophysiological parameters on the last mRS, considered as binary outcome (absence or presence of severe disability, i.e., <4/≥4 mRS). Moreover, we used Spearman's rank correlation coefficient to evaluate the relationship between disease duration and last mRS. We observed a significant relationship between last mRS and baseline mRS [p = 0.015, z = 2.44, OR 5.15 (CI 1.38-19.22)] and age of onset [p = 0.017, z = 2.39, OR 1.13 (CI 1.02-1.27) per additional year of age of onset]. There was no correlation between disease duration and last mRS. Our data suggest that a worse clinical status at the beginning of disease and an older age at onset may be negative prognostic factors of long-term disability independent from disease duration.

Immune Gamma Globulin Therapeutic Indications in Immune Deficiency and Autoimmunity

Immune gamma globulin (IgG) has a long history in the treatment of both primary immune deficiency and autoimmune disorders. Disease indications continue to expand and new-generation products increase the versatility of delivery. This review encompasses a historical perspective as well as current and future implications of human immune globulin for the treatment of immune-mediated illness.

Immunomodulatory treatment other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a disease that causes progressive or relapsing and remitting weakness and numbness. It is probably caused by an autoimmune process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial. This review was first published in 2003 and has been updated most recently in 2016.

OBJECTIVES

To assess the effects of immunomodulatory and immunosuppressive agents other than corticosteroids, immunoglobulin, and plasma exchange in CIDP.

SEARCH METHODS

On 24 May 2016, we searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 4) in the Cochrane Library, MEDLINE, Embase, CINAHL, and LILACS for completed trials, and clinical trial registers for ongoing trials. We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents, such as azathioprine, cyclophosphamide, methotrexate, ciclosporin, mycophenolate mofetil, and rituximab, and all immunomodulatory agents, such as interferon (IFN) alfa and IFN beta, in participants fulfilling standard diagnostic criteria for CIDP. We included all comparisons of these agents with placebo, another treatment, or no treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We wanted to measure the change in disability after one year as our primary outcome. Our secondary outcomes were change in disability after four or more weeks (from randomisation); change in impairment after at least one year; change in maximum motor nerve conduction velocity and compound muscle action potential amplitude after one year; and for participants who were receiving corticosteroids or intravenous immunoglobulin (IVIg), the amount of this medication given during at least one year after randomisation. Participants with one or more serious adverse events during the first year was also a secondary outcome.

MAIN RESULTS

Four trials fulfilled the selection criteria: one of azathioprine (27 participants), two of IFN beta-1a (77 participants in total) and one of methotrexate (60 participants). The risk of bias was considered low in the trials of IFN beta-1a and methotrexate but high in the trial of azathioprine. None of the trials showed significant benefit in any of the outcomes selected by their authors. The results of the outcomes which approximated most closely to the primary outcome for this review were as follows.In the azathioprine trial there was a median improvement in the Neuropathy Impairment Scale (scale range 0 to 280) after nine months of 29 points (range 49 points worse to 84 points better) in the azathioprine and prednisone treated participants compared with 30 points worse (range 20 points worse to 104 points better) in the prednisone alone group. There were no reports of adverse events.In a cross-over trial of IFN beta-1a with 20 participants, the treatment periods were 12 weeks. The median improvement in the Guy's Neurological Disability Scale (range 1 to 10) was 0.5 grades (interquartile range (IQR) 1.8 grades better to zero grade change) in the IFN beta-1a treatment period and 0.5 grades (IQR 1.8 grades better to 1.0 grade worse) in the placebo treatment period. There were no serious adverse events in either treatment period.In a parallel group trial of IFN beta-1a with 67 participants, none of the outcomes for this review was available. The trial design involved withdrawal from ongoing IVIg treatment. The primary outcome used by the trial authors was total IVIg dose administered from week 16 to week 32 in the placebo group compared with the IFN beta-1a groups. This was slightly but not significantly lower in the combined IFN beta-1a groups (1.20 g/kg) compared with the placebo group (1.34 g/kg, P = 0.75). There were four participants in the IFN beta-1a group and none in the placebo group with one or more serious adverse events, risk ratio (RR) 4.50 (95% confidence interval (CI) 0.25 to 80.05).The methotrexate trial had a similar design involving withdrawal from ongoing corticosteroid or IVIg treatment. At the end of the trial (approximately 40 weeks) there was no significant difference in the change in the Overall Neuropathy Limitations Scale, a disability scale (scale range 0 to 12), the median change being 0 (IQR -1 to 0) in the methotrexate group and 0 (IQR -0.75 to 0) in the placebo group. These changes in disability might have been confounded by the reduction in corticosteroid or IVIg dose required by the protocol. There were three participants in the methotrexate group and one in the placebo with one or more serious adverse events, RR 3.56 (95% CI 0.39 to 32.23).

AUTHORS' CONCLUSIONS

Low-quality evidence from randomised trials does not show significant benefit from azathioprine or interferon beta-1a and moderate-quality evidence from one randomised trial does not show significant benefit from a relatively low dose of methotrexate for the treatment of CIDP. None of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures relevant to people with CIDP, and longer treatment durations.

Treatments for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP): an overview of systematic reviews

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a chronic progressive or relapsing and remitting disease that usually causes weakness and sensory loss. The symptoms are due to autoimmune inflammation of peripheral nerves. CIPD affects about 2 to 3 per 100,000 of the population. More than half of affected people cannot walk unaided when symptoms are at their worst. CIDP usually responds to treatments that reduce inflammation, but there is disagreement about which treatment is most effective.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews (CSRs) and non-Cochrane systematic reviews of any treatment for CIDP and to compare the effects of treatments.

METHODS

We considered all systematic reviews of randomised controlled trials (RCTs) of any treatment for any form of CIDP. We reported their primary outcomes, giving priority to change in disability after 12 months.Two overview authors independently identified published systematic reviews for inclusion and collected data. We reported the quality of evidence using GRADE criteria. Two other review authors independently checked review selection, data extraction and quality assessments.On 31 October 2016, we searched the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects (in theCochrane Library), MEDLINE, Embase, and CINAHL Plus for systematic reviews of CIDP. We supplemented the RCTs in the existing CSRs by searching on the same date for RCTs of any treatment of CIDP (including treatment of fatigue or pain in CIDP), in the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL Plus.

MAIN RESULTS

Five CSRs met our inclusion criteria. We identified 23 randomised trials, of which 15 had been included in these CSRs. We were unable to compare treatments as originally planned, because outcomes and outcome intervals differed. CorticosteroidsIt is uncertain whether daily oral prednisone improved impairment compared to no treatment because the quality of the evidence was very low (1 trial, 28 participants). According to moderate-quality evidence (1 trial, 41 participants), six months' treatment with high-dose monthly oral dexamethasone did not improve disability more than daily oral prednisolone. Observational studies tell us that prolonged use of corticosteroids sometimes causes serious side-effects. Plasma exchangeAccording to moderate-quality evidence (2 trials, 59 participants), twice-weekly plasma exchange produced more short-term improvement in disability than sham exchange. In the largest observational study, 3.9% of plasma exchange procedures had complications. Intravenous immunoglobulinAccording to high-quality evidence (5 trials, 269 participants), intravenous immunoglobulin (IVIg) produced more short-term improvement than placebo. Adverse events were more common with IVIg than placebo (high-quality evidence), but serious adverse events were not (moderate-quality evidence, 3 trials, 315 participants). One trial with 19 participants provided moderate-quality evidence of little or no difference in short-term improvement of impairment with plasma exchange in comparison to IVIg. There was little or no difference in short-term improvement of disability with IVIg in comparison to oral prednisolone (moderate-quality evidence; 1 trial, 29 participants) or intravenous methylprednisolone (high-quality evidence; 1 trial, 45 participants). One unpublished randomised open trial with 35 participants found little or no difference in disability after three months of IVIg compared to oral prednisone; this trial has not yet been included in a CSR. We know from observational studies that serious adverse events related to IVIg do occur. Other immunomodulatory treatmentsIt is uncertain whether the addition of azathioprine (2 mg/kg) to prednisone improved impairment in comparison to prednisone alone, as the quality of the evidence is very low (1 trial, 27 participants). Observational studies show that adverse effects truncate treatment in 10% of people.According to low-quality evidence (1 trial, 60 participants), compared to placebo, methotrexate 15 mg/kg did not allow more participants to reduce corticosteroid or IVIg doses by 20%. Serious adverse events were no more common with methotrexate than with placebo, but observational studies show that methotrexate can cause teratogenicity, abnormal liver function, and pulmonary fibrosis.According to moderate-quality evidence (2 trials, 77 participants), interferon beta-1a (IFN beta-1a) in comparison to placebo, did not allow more people to withdraw from IVIg. According to moderate-quality evidence, serious adverse events were no more common with IFN beta-1a than with placebo.We know of no other completed trials of immunosuppressant or immunomodulatory agents for CIDP. Other treatmentsWe identified no trials of treatments for fatigue or pain in CIDP. Adverse effectsNot all trials routinely collected adverse event data; when they did, the quality of evidence was variable. Adverse effects in the short, medium, and long term occur with all interventions. We are not able to make reliable comparisons of adverse events between the interventions included in CSRs.

AUTHORS' CONCLUSIONS

We cannot be certain based on available evidence whether daily oral prednisone improves impairment compared to no treatment. However, corticosteroids are commonly used, based on widespread availability, low cost, very low-quality evidence from observational studies, and clinical experience. The weakness of the evidence does not necessarily mean that corticosteroids are ineffective. High-dose monthly oral dexamethasone for six months is probably no more or less effective than daily oral prednisolone. Plasma exchange produces short-term improvement in impairment as determined by neurological examination, and probably produces short-term improvement in disability. IVIg produces more short-term improvement in disability than placebo and more adverse events, although serious side effects are probably no more common than with placebo. There is no clear difference in short-term improvement in impairment with IVIg when compared with intravenous methylprednisolone and probably no improvement when compared with either oral prednisolone or plasma exchange. According to observational studies, adverse events related to difficult venous access, use of citrate, and haemodynamic changes occur in 3% to17% of plasma exchange procedures.It is uncertain whether azathioprine is of benefit as the quality of evidence is very low. Methotrexate may not be of benefit and IFN beta-1a is probably not of benefit.We need further research to identify predictors of response to different treatments and to compare their long-term benefits, safety and cost-effectiveness. There is a need for more randomised trials of immunosuppressive and immunomodulatory agents, routes of administration, and treatments for symptoms of CIDP.

Two years' long-term follow up in chronic inflammatory demyelinating polyradiculoneuropathy: efficacy of intravenous immunoglobulin treatment

BACKGROUND

Administration of intravenous immunoglobulins (IVIgs) is established for long-term treatment of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Prevention of secondary axonal loss going along with permanent clinical disability and muscular atrophy is a major aim in CIDP therapy. To assess long-term clinical efficacy of IVIg treatment despite heterogenous disease course and variable complaints reported by the patients, long-term electrophysiological monitoring was performed for systematic evaluation of therapeutic efficacy of IVIg.

METHODS

A total of 21 patients with CIDP treated with IVIg 1 g/kg bodyweight every 3-6 weeks were examined electrophysiologically every 12 months over a period of 2 years.

RESULTS

Assessment of clinical symptoms, using the Inflammatory Neuropathy Cause and Treatment (INCAT) and Hughes functional grading score (F-score) revealed improvement of motor and sensory symptoms over a period of 2 years. As electrophysiological results remained stable, IVIg treatment seems to be suitable to prevent axonal loss in CIDP.

CONCLUSIONS

This study confirms efficacy of IVIg as firstline therapy in CIDP. Doses and frequency of IVIg application should be adapted based on clinical evaluation and analysis of long-term electrophysiological findings.

The Effect of Immunonutrition on the Postoperative Complications in Thymoma with Myasthenia Gravis

Object. To test whether preoperative immunonutrition is efficacious in reducing postoperative complications in patients of thymoma with myasthenia gravis (MG). Material and Methods. A total of 244 patients operated on for thymoma with myasthenia gravis were prospectively assigned to two groups, each receiving seven-day preoperative and seven-day postoperative nutrition. The patients in immunonutrition group were given oral immunonutrition (IN). The patients in control group received oral standard nutrition. Immunonutritional and inflammatory biomarkers (IgA, IgG, IgM, CD3t, CD4t, CD8t, CD4t/CD8t ratio, NK-cell, prealbumin, albumin, white blood cells counts, and C-reactive protein) and clinical variables (age, gender, BMI, performance status, type of thymoma, type of MG, operative time, pathology, operative approach, postoperative complications, quantity of drainage, hospital stays) were examined. Results. A significant reduction in the length of hospital stay, quantity of drainage, and postoperative complications was observed in the IN group (p < 0.05). An increase in the level of IgA, IgG, IgM, CD3+T, CD4+T, CD4+T/CD8+T, WBC, CRP, and NK-cell in the IN group was observed after thymectomy, while a decrease was seen with regard to prealbumin and albumin (p < 0.05). Conclusion. Preoperative immunonutrition support is effective in reducing postoperative complications in patients of thymoma with MG. It helps to lower the risk of postoperative infectious complications and hospital stays.

Dose-dependent inhibition of demyelination and microglia activation by IVIG

Objective

Intravenous immunoglobulin (IVIG) is an established treatment for numerous autoimmune conditions. Clinical trials of IVIG for multiple sclerosis, using diverse dose regimens, yielded controversial results. The aim of this study is to dissect IVIG effector mechanisms on demyelination in an ex vivo model of the central nervous system (CNS)‐immune interface.

Methods

Using organotypic cerebellar slice cultures (OSC) from transgenic mice expressing green fluorescent protein (GFP) in oligodendrocytes/myelin, we induced extensive immune‐mediated demyelination and oligodendrocyte loss with an antibody specific for myelin oligodendrocyte glycoprotein (MOG) and complement. Protective IVIG effects were assessed by live imaging of GFP expression, confocal microscopy, immunohistochemistry, gene expression analysis and flow cytometry.

Results

IVIG protected OSC from demyelination in a dose‐dependent manner, which was at least partly attributed to interference with complement‐mediated oligodendroglia damage, while binding of the anti‐MOG antibody was not prevented. Staining with anti‐CD68 antibodies and flow cytometry confirmed that IVIG prevented microglia activation and oligodendrocyte death, respectively. Equimolar IVIG‐derived Fab fragments or monoclonal IgG did not protect OSC, while Fc fragments derived from a polyclonal mixture of human IgG were at least as potent as intact IVIG.

Interpretation

Both intact IVIG and Fc fragments exert a dose‐dependent protective effect on antibody‐mediated CNS demyelination and microglia activation by interfering with the complement cascade and, presumably, interacting with local immune cells. Although this experimental model lacks blood–brain barrier and peripheral immune components, our findings warrant further studies on optimal dose finding and alternative modes of application to enhance local IVIG concentrations at the site of tissue damage.