Intravenous immunoglobulin in paediatric neurology: safety, adherence to guidelines, and long-term outcome

Incidence of adverse events related to intravenous immunoglobulin therapy in children

BACKGROUND

Intravenous immunoglobulin (IVIG) therapy is used in the treatment of pediatric diseases, although data about IVIG-related adverse events (IVIG-AEs) are limited. Objectives of this study were to document the incidence of IVIG-AEs in pediatric hospitalized patients and to identify risk factors for IVIG-AEs.

METHODS

This retrospective cohort study included patients <18 years old who received IVIG therapy while admitted at a Canadian pediatric tertiary care center between 2016 and 2020. Patients and IVIG-perfusions characteristics were collected, as well as IVIG-AEs. Bivariate and multivariable logistic regressions were used to explore predictors of IVIG-AEs.

RESULTS

We included 228 children, totaling 478 IVIG perfusions. Indications included treatment for inflammatory (52.6%), autoimmune disorders (35.5%), and immunoglobulin replacement (11.8%). A total of 213 IVIG-AEs were reported. Fever (13.6%) and headache (6.7%) were the most frequent IVIG-AEs. Most IVIG-AEs were mild (57%) or moderate (31%) in severity, but 12% were severe reactions. The following factors were predictive of IVIG-AEs in univariate analyses: older age (OR 1.14 [95% CI: 1.07-1.21]), dehydration (OR 2.55 [95% CI: 1.43-4.55]), concurrent allergies (OR 2.87 [95% CI: 1.26-6.56]), first perfusion (OR 1.53 [95% CI: 1.02-2.30]), and higher dosage (OR 2.14 [95% CI: 1.39-3.33]). Concurrent steroids decreased the risk of IVIG-AEs (OR 0.43 [95% CI: 0.19-0.96]). Older age and higher IVIG dose remained independent predictors of IVIG-AEs in multivariable analyses.

CONCLUSIONS

Mild IVIG-AEs are frequent in children, and serious reactions may occur. Prospective studies are needed to confirm risk factors for IVIG-AEs and to evaluate how to best prevent them.

Anti-Inflammatory and Immunomodulatory Effect of High-Dose Immunoglobulins in Children: From Approved Indications to Off-Label Use

BACKGROUND

The large-scale utilization of immunoglobulins in patients with inborn errors of immunity (IEIs) since 1952 prompted the discovery of their key role at high doses as immunomodulatory and anti-inflammatory therapy, in the treatment of IEI-related immune dysregulation disorders, according to labelled and off-label indications. Recent years have been dominated by a progressive imbalance between the gradual but constant increase in the use of immunoglobulins and their availability, exacerbated by the SARS-CoV-2 pandemic.

OBJECTIVES

To provide pragmatic indications for a need-based application of high-dose immunoglobulins in the pediatric context.

SOURCES

A literature search was performed using PubMed, from inception until 1st August 2023, including the following keywords: anti-inflammatory; children; high dose gammaglobulin; high dose immunoglobulin; immune dysregulation; immunomodulation; immunomodulatory; inflammation; intravenous gammaglobulin; intravenous immunoglobulin; off-label; pediatric; subcutaneous gammaglobulin; subcutaneous immunoglobulin. All article types were considered.

IMPLICATIONS

In the light of the current imbalance between gammaglobulins' demand and availability, this review advocates the urgency of a more conscious utilization of this medical product, giving indications about benefits, risks, cost-effectiveness, and administration routes of high-dose immunoglobulins in children with hematologic, neurologic, and inflammatory immune dysregulation disorders, prompting further research towards a responsible employment of gammaglobulins and improving the therapeutical decisional process.

Diagnosis and Management of Suspected Pediatric Autoimmune Encephalitis: A Comprehensive, Multidisciplinary Approach and Review of Literature

Autoimmune encephalitis is an increasingly recognized entity in children. When treated promptly, favorable outcomes are seen in a majority of pediatric patients. However, recognition of autoimmune encephalitis in young patients is challenging. Once autoimmune encephalitis is suspected, additional difficulties exist regarding timing of treatment initiation and duration of treatment, as evidence to guide management of these patients is emerging. Here, we review available literature regarding pediatric autoimmune encephalitis and present our institution's comprehensive approach to the evaluation and management of the disease. These guidelines were developed through an iterative process involving both pediatric neurologists and rheumatologists.

Efficacy and safety of intravenous and subcutaneous immunoglobulin therapy in idiopathic inflammatory myopathy: A systematic review and meta-analysis

OBJECTIVE

To perform a systematic review and meta-analysis on the efficacy and safety of intravenous (IVIg) and subcutaneous (SCIg) immunoglobulin (Ig) therapy in the treatment of idiopathic inflammatory myopathy (IIM) and juvenile dermatomyositis (JDM).

METHODS

PubMed, Embase and SCOPUS were searched to identify studies on Ig therapy in patients with IIM and/or JDM (2010-2020). Outcome measures were complete response (CR) or partial response (PR) in terms of muscle power and extramuscular disease activity measures on the International Myositis Assessment and Clinical Studies Group (IMACS) core set domains.

RESULTS

Twenty-nine studies were included (n = 576, 544 IIM, 32 JDM). Muscle power PR with pooled Ig therapy was 88.5% (95% confidence interval (CI): 80.6-93.5, n = 499) and PR with SCIg treatment was 96.61% (95% CI: 87.43-99.15, n = 59). Pooled PR with first-line use of IVIg was 77.07% (95% CI: 61.25-92.89, n = 80). Overall, mean time to response was 2.9 months (95% CI: 1.9-4.1). Relapse was seen in 22.76% (95% CI: 14.9-33). Studies on cutaneous disease activity and dysphagia showed significant treatment responses. Glucocorticoid and immunosuppressant sparing effect was seen in 40.9% (95% CI: 20-61.7) and 42.2% (95% CI: 20.4-64.1) respectively. Ig therapy was generally safe with low risk of infection (1.37%, 95% CI: 0.1-2.6).

CONCLUSIONS

Add-on Ig therapy improves muscle strength in patients with refractory IIM, but evidence on Ig therapy in new-onset disease and extramuscular disease activity is uncertain.

Multiple extubation failures following a rhino-enteroviral infection: A unique case report in a pediatric patient

This case report reviews the hospital course of a 15-month-old girl admitted to the PICU for acute respiratory failure due to enterovirus infection; who subsequently had multiple extubation failures secondary to acute transverse myelitis. This rare presentation highlights the importance of assessing the neurological status in a patient with rhino-enteroviral respiratory infection and of considering acute transverse myelitis as an etiology for difficulty with extubation.

E.U. paediatric MOG consortium consensus: Part 5 - Treatment of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

In recent years, the understanding about the different clinical phenotypes, diagnostic and prognostic factors of myelin oligodendrocyte glycoprotein-antibody-associated disorders (MOGAD) has significantly increased. However, there is still lack of evidence-based treatment protocols for acute attacks and children with a relapsing course of the disease. Currently used acute and maintenance treatment regimens are derived from other demyelinating central nervous system diseases and are mostly centre-specific. Therefore, this part of the Paediatric European Collaborative Consensus attempts to provide recommendations for acute and maintenance therapy based on clinical experience and evidence available from mainly retrospective studies. In the acute attack, intravenous methylprednisolone (IVMP) leads to a favourable outcome in the majority of patients and can be followed by tapering of oral steroids up to a maximum of three months to maintain the benefit of acute treatment by suppressing disease activity. Intravenous immunoglobulins (IVIG) and plasmapheresis constitute second-line therapies in case of insufficient response to IVMP. After a first relapse, maintenance treatment should be started in order to prevent further relapses and the possibility of permanent sequelae. Four first-line therapies consisting of rituximab (RTX), azathioprine, mycophenolate mofetil or monthly IVIG have been identified by the consensus group. In case of further relapses despite maintenance treatment, the consensus group recommends treatment escalation with RTX or IVIG, followed by combining those two, and ultimately adding maintenance oral steroids. Many open questions remain which need to be addressed in further international prospective evaluation of MOGAD treatment. This international collaboration is essential to expand the state of current knowledge.

Predictive factors of first dosage intravenous immunoglobulin-related adverse effects in children

BACKGROUND

Intravenous immunoglobulin (IVIG) therapy is used in the treatment of various diseases, and IVIG-related adverse effects (IVIG-AEs) vary from mild to severe. However, the mechanisms underlying IVIG-AEs and the potential predictive factors are not clear. This study investigated whether certain IVIG-AEs can be predicted before IVIG administration.

STUDY DESIGN AND METHODS

This retrospective cohort study at the Division of Neurology, Saitama Children's Medical Center included patients enrolled from 2008 to 2018 who were < 18 years old and received IVIG for the first time. IVIG-AEs were classified according to the Common Terminology Criteria for Adverse Events version 5.0.

RESULTS

A total of 104 patients fulfilled the inclusion criteria. The rate of IVIG-AEs was 37.5% (39/104). The most frequent IVIG-AEs were fever (41.0% [16/39]) and headache (38.5% [15/39]). AEs were below grade 2 in all except one patient and there were no grade 4 AEs. High serum total protein (TP) level was significantly related to the occurrence of IVIG-AEs (odds ratio, 14.8; 95% confidence interval, 2.4-90.5; P < 0.01). The optimal cutoff TP level was 6.7 g/dL. Although low WBC count and immunoglobulin G level may be predictive risk factors of IVIG-AEs, it was not confirmed in this study.

CONCLUSION

IVIG-AEs occurred in 37.5% of cases, and most were mild. TP was the best predictive risk factor of IVIG-AEs before IVIG administration. These results may aid in elucidating the mechanism underlying IVIG-AEs.

Pharmacotherapy for Pediatric Convulsive Status Epilepticus

Convulsive status epilepticus (CSE) is one of the most common pediatric neurological emergencies. Ongoing seizure activity is a dynamic process and may be associated with progressive impairment of gamma-aminobutyric acid (GABA)-mediated inhibition due to rapid internalization of GABA_A receptors. Further hyperexcitability may be caused by AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) and NMDA (N-methyl-D-aspartic acid) receptors moving from subsynaptic sites to the synaptic membrane. Receptor trafficking during prolonged seizures may contribute to difficulties treating seizures of longer duration and may provide some of the pathophysiological underpinnings of established and refractory SE (RSE). Simultaneously, a practice change toward more rapid initiation of first-line benzodiazepine (BZD) treatment and faster escalation to second-line non-BZD treatment for established SE is in progress. Early administration of the recommended BZD dose is suggested. For second-line treatment, non-BZD anti-seizure medications (ASMs) include valproate, fosphenytoin, or levetiracetam, among others, and at this point there is no clear evidence that any one of these options is better than the others. If seizures continue after second-line ASMs, RSE is manifested. RSE treatment consists of bolus doses and titration of continuous infusions under continuous electro-encephalography (EEG) guidance until electrographic seizure cessation or burst-suppression. Ultimately, etiological workup and related treatment of CSE, including broad spectrum immunotherapies as clinically indicated, is crucial. A potential therapeutic approach for future studies may entail consideration of interventions that may accelerate diagnosis and treatment of SE, as well as rational and early polytherapy based on synergism between ASMs by utilizing medications targeting different mechanisms of epileptogenesis and epileptogenicity.

Acute Transverse and Flaccid Myelitis in Children

PURPOSE OF REVIEW

The etiologies of myelitis in children are broad, and our understanding of inflammatory myelopathies in the pediatric population continues to evolve. Acute flaccid myelitis (AFM), increasingly linked to enterovirus infections, has risen in incidence over recent years. As with other infectious myelopathies, AFM can be challenging to distinguish from inflammatory causes of acute transverse myelitis (ATM) at initial presentation. This review outlines an approach to the treatment of children presenting with myelopathy of suspected inflammatory etiology, with attention to how management may differ in the specific case of acute flaccid myelitis.

RECENT FINDINGS

Although high-quality evidence is limited, intravenous corticosteroids, intravenous immunoglobulin, and plasma exchange have important roles in the acute management of ATM. Spinal cord injury in AFM, though similar to ATM in clinical presentation, is largely mediated by direct infection as opposed to a primary inflammatory process, and treatment with corticosteroids may worsen outcomes. Awareness of the distinguishing clinical features of AFM and the underlying inflammatory conditions that commonly manifest with ATM is essential to judicious selection of appropriate acute (and potentially chronic) therapies in children presenting with myelitis.

Beyond the brain: A multi-system inflammatory subtype of autism spectrum disorder

An immune-mediated subtype of autism spectrum disorder (ASD) has long been hypothesized. This article reviews evidence from family history studies of autoimmunity, immunogenetics, maternal immune activation, neuroinflammation, and systemic inflammation, which suggests immune dysfunction in ASD. Individuals with ASD have higher rates of co-morbid medical illness than the general population. Major medical co-morbidities associated with ASD are discussed by body system. Mechanisms by which FDA-approved and emerging treatments for ASD act upon the immune system are then reviewed. We conclude by proposing the hypothesis of an immune-mediated subtype of ASD which is characterized by systemic, multi-organ inflammation or immune dysregulation with shared mechanisms that drive both the behavioral and physical illnesses associated with ASD. Although gaps in evidence supporting this hypothesis remain, benefits of this conceptualization include framing future research questions that will help define a clinically meaningful subset of patients and focusing clinical interactions on early detection and treatment of high-risk medical illnesses as well as interfering behavioral signs and symptoms across the lifespan.

Management of antibody-mediated autoimmune encephalitis in adults and children: literature review and consensus-based practical recommendations

Autoimmune encephalitis associated with antibodies against neuronal surface targets (NSAE) are rare but still underrecognized conditions that affect adult and pediatric patients. Clinical guidelines have recently been published with the aim of providing diagnostic clues regardless of antibody status. These syndromes are potentially treatable but the choice of treatment and its timing, as well as differential diagnoses, long-term management, and clinical and paraclinical follow-up, remain major challenges. In the absence of evidence-based guidelines, management of these conditions is commonly based on single-center expertise.Taking into account different published expert recommendations in addition to the multicenter experience of the Italian Working Group on Autoimmune Encephalitis, both widely accepted and critical aspects of diagnosis, management and particularly of immunotherapy for NSAE have been reviewed and are discussed.Finally, we provide consensus-based practical advice for managing hospitalization and follow-up of patients with NSAE.

Febrile infection-related epilepsy syndrome (FIRES): prevalence, impact and management strategies

Febrile infection-related epilepsy syndrome (FIRES) is a rare catastrophic epileptic encephalopathy with a yet undefined etiology, affecting healthy children. It is characterized by acute manifestation of recurrent seizures or refractory status epilepticus preceded by febrile illness, but without evidence of infectious encephalitis. To date, the absence of specific biomarkers poses a significant diagnostic challenge; nonetheless, early diagnosis is very important for optimal management. FIRES is mostly irreversible and its sequelae include drug-resistant epilepsy and neuropsychological impairments. The treatment of FIRES represents a significant challenge for clinicians and is associated with low success rates. Early introduction of ketogenic diet seems to represent the most effective and promising treatment. This review aims to highlight the most recent insights on clinical features, terminology, epidemiology, pathogenesis, diagnostic challenges and therapeutic options.

Mycophenolate mofetil, azathioprine and methotrexate usage in paediatric anti-NMDAR encephalitis: A systematic literature review

BACKGROUND

Available data on mycophenolate mofetil (MMF), azathioprine (AZA) and methotrexate (MTX) for paediatric-onset anti-N-methyl-d-aspartate receptor encephalitis (anti-NMDARE) is limited.

METHODS

Systematic literature review on patients treated with MMF/AZA/MTX for paediatric-onset anti-NMDARE, with focus on modes of use, efficacy and safety.

RESULTS

87 patients were included (age at onset median 11 years, range 0.8-18 years; 69% females). 46% had a relapsing course. 52% received MMF, 27% AZA, 15% MTX, and 6% a combination of MMF/AZA/MTX (7 patients received intrathecal MTX). Before MMF/AZA/MTX, 100% patients received steroids, 83% intravenous immunoglobulin and 45% plasma exchange, and 50% received second-line treatments (rituximab/cyclophosphamide). MMF/AZA/MTX were administered >6 months from onset in 51%, and only after relapse in 40%. Worst mRS before MMF/AZA/MTX was median 4.5 (range 3-5). At last follow-up (median 2 years, range 0.2-8.6), median mRS was 1 (range 0-6). Median annualised relapse rate was 0.4 (range 0-6.7) pre-MMF/AZA/MTX (excluding first events), and 0 on MMF/AZA/MTX (mean 0.03, range 0-0.8). 7% patients relapsed on MMF/AZA/MTX. These relapsing patients had low rate of second-line treatments before MMF/AZA/MTX (25%), long median time between onset and MMF/AZA/MTX usage (18 months), and frequently they were started on MMF/AZA/MTX only after relapse (75%). Relapse rate was lower among patients who received first immune therapy ≤30 days (25%) than later (64%), who received second-line treatments at first event (14%) rather than not (64%), who were started on MMF/AZA/MTX after the first (12%) rather than subsequent events (17%), and who were started on MMF/AZA/MTX ≤3 months from onset (33%) rather than later (53%). Adverse reactions to MMF/AZA/MTX occurred in 2 cases (cytomegalovirus colitis and respiratory infection), of grade 3 Common Terminology Criteria for Adverse Events v4.0.

DISCUSSION

Our literature review disclosed heterogeneity in the use of MMF/AZA/MTX in paediatric-onset anti-NMDARE. MMF/AZA/MTX usage is mostly restricted to retrospective cohort descriptions. These agents may reduce risk of relapse, and have a reasonable safety profile, however data on larger cohorts are required to definitively determine effect.

[Approach for identifying of treatment option for pediatric patients in Guillain-Barre syndrome considering results of pharmacoeconomic analysis]

AIM

A pharmacoeconomic analysis of direct costs on treatment with high dose intravenous immunoglobulins (IVIG) and plasmapheresis (PP) in children.

MATERIAL AND METHODS

Literature data on the pathogenesis of Guillain-Barre syndrome (GBS) were analyzed. The results of pharmacoeconomic analysis of direct costs on treatment of GBS using IVIG and PP are presented. Risks for complications during treatment with IVIG and PP are calculated.

RESULTS AND CONCLUSION

The pharmacoeconomic analysis demonstrates comparable costs of treatment with IVIG or PP in the Russian Federation. Nevertheless, a less number of complications, convenience in use and the good safety and tolerability profile make it more preferable to this group of patients. In a clinical case of a 7-year child described in the article, treatment with 10% IVIG - privigen in dose 2 g/kg during 5 days started in the 3^rd week of disease showed a marked positive effect.

Clinical Management of Pediatric Acute-Onset Neuropsychiatric Syndrome: Part II-Use of Immunomodulatory Therapies

Introduction: Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) is a clinically heterogeneous disorder with a number of different etiologies and disease mechanisms. Inflammatory and postinfectious autoimmune presentations of PANS occur frequently, with some clinical series documenting immune abnormalities in 75%-80% of patients. Thus, comprehensive treatment protocols must include immunological interventions, but their use should be reserved only for PANS cases in which the symptoms represent underlying neuroinflammation or postinfectious autoimmunity, as seen in the PANDAS subgroup (Pediatric Autoimmune Neuropsychiatric Disorders associated with Streptococcal infections). Methods: The PANS Research Consortium (PRC) immunomodulatory task force is comprised of immunologists, rheumatologists, neurologists, infectious disease experts, general pediatricians, psychiatrists, nurse practitioners, and basic scientists with expertise in neuroimmunology and PANS-related animal models. Preliminary treatment guidelines were created in the Spring of 2014 at the National Institute of Health and refined over the ensuing 2 years over conference calls and a shared web-based document. Seven pediatric mental health practitioners, with expertise in diagnosing and monitoring patients with PANS, were consulted to create categories in disease severity and critically review final recommendations. All authors played a role in creating these guidelines. The views of all authors were incorporated and all authors gave final approval of these guidelines. Results: Separate guidelines were created for the use of immunomodulatory therapies in PANS patients with (1) mild, (2) moderate-to-severe, and (3) extreme/life-threatening severity. For mildly impairing PANS, the most appropriate therapy may be "tincture of time" combined with cognitive behavioral therapy and other supportive therapies. If symptoms persist, nonsteroidal anti-inflammatory drugs and/or short oral corticosteroid bursts are recommended. For moderate-to-severe PANS, oral or intravenous corticosteroids may be sufficient. However, intravenous immunoglobulin (IVIG) is often the preferred treatment for these patients by most PRC members. For more severe or chronic presentations, prolonged corticosteroid courses (with taper) or repeated high-dose corticosteroids may be indicated. For PANS with extreme and life-threatening impairment, therapeutic plasma exchange is the first-line therapy given either alone or in combination with IVIG, high-dose intravenous corticosteroids, and/or rituximab. Conclusions: These recommendations will help guide the use of anti-inflammatory and immunomodulatory therapy in the treatment of PANS.

Immunotherapeutics in Pediatric Autoimmune Central Nervous System Disease: Agents and Mechanisms

Beyond the major advances produced by careful clinical-radiological phenotyping and biomarker development in autoimmune central nervous system disorders, a comprehensive knowledge of the range of available immune therapies and a deeper understanding of their action should benefit therapeutic decision-making. This review discusses the agents used in neuroimmunology and their mechanisms of action. First-line treatments typically include corticosteroids, intravenous immunoglobulin, and plasmapheresis, while for severe disease second-line "induction" agents such as rituximab or cyclophosphamide are used. Steroid-sparing agents such as mycophenolate, azathioprine, or methotrexate are often used in potentially relapsing or corticosteroid-dependent diseases. Lessons from adult neuroimmunology and rheumatology could be translated into pediatric autoimmune central nervous system disease in the future, including the potential utility of monoclonal antibodies targeting lymphocytes, adhesion molecules for lymphocytic migration, cytokines or their receptors, or complement. Finally, many agents used in other fields have multiple mechanisms of action, including immunomodulation, with potential usefulness in neuroimmunology, such as antibiotics, psychotropic drugs, probiotics, gut health, and ketogenic diet. All currently accepted and future potential agents have adverse effects, which can be severe; therefore, a "risk-versus-benefit" determination should guide therapeutic decision-making.

The Spectrum of Inflammatory Acquired Demyelinating Syndromes in Children

Acquired demyelinating syndromes in childhood comprise a spectrum of monophasic and recurrent inflammatory conditions of the central nervous system. Examples of monophasic conditions include, clinically isolated syndromes such as optic neuritis and transverse myelitis, as well as acute disseminated encephalomyelitis, whereas recurrent disorders include entities such as multiple sclerosis and neuromyelitis optica spectrum disorder. Knowledge about these disorders has expanded due to rigorously evaluated diagnostic criteria, magnetic resonance imaging features, outcomes, and serum biomarkers in these disorders. This review aims to provide a summary of clinical developments in pediatric acquired demyelinating syndromes, with a special focus on diagnostic criteria, neuroinflammatory markers, burden of disease in addition to current and potential future treatment options.

Advances in Autoimmune Epilepsy Associated with Antibodies, Their Potential Pathogenic Molecular Mechanisms, and Current Recommended Immunotherapies

In this comprehensive article, we present an overview of some most common autoimmune antibodies believed to be potentially pathogenic for autoimmune epilepsies and elaborate their pathogenic mode of action in molecular levels based on the existing knowledge. Findings of the studies of immunemodulatory treatments for epilepsy are also discussed, and guidelines for immunotherapy are sorted out. We aim to summarize the emerging understanding of different pathogenic mechanisms of autoantibodies and clinical immunotherapy regimens to open up therapeutic possibilities for future optimum therapy. We conclude that early diagnosis of autoimmune epilepsy is of great significance, as early immune treatments have useful disease-modifying effects on some epilepsies and can facilitate the recovery.

Systematic review of immunoglobulin use in paediatric neurological and neurodevelopmental disorders

AIM

A systematic literature review of intravenous immunoglobulin (IVIG) treatment of paediatric neurological conditions was performed to summarize the evidence, provide recommendations, and suggest future research.

METHOD

A MEDLINE search for articles reporting on IVIG treatment of paediatric neuroinflammatory, neurodevelopmental, and neurodegenerative conditions published before September 2015, excluding single case reports and those not in English. Owing to heterogeneous outcome measures, meta-analysis was not possible. Findings were combined and evidence graded.

RESULTS

Sixty-five studies were analysed. IVIG reduces recovery time in Guillain-Barré syndrome (grade B). IVIG is as effective as corticosteroids in chronic inflammatory demyelinating polyradiculoneuropathy (grade C), and as effective as tacrolimus in Rasmussen syndrome (grade C). IVIG improves recovery in acute disseminated encephalomyelitis (grade C), reduces mortality in acute encephalitis syndrome with myocarditis (grade C), and improves function and stabilizes disease in myasthenia gravis (grade C). IVIG improves outcome in N-methyl-d-aspartate receptor encephalitis (grade C) and opsoclonus-myoclonus syndrome (grade C), reduces cataplexy symptoms in narcolepsy (grade C), speeds recovery in Sydenham chorea (grade C), reduces tics in selected cases of Tourette syndrome (grade D), and improves symptoms in paediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (grade B).

INTERPRETATION

IVIG is a useful therapy in selected neurological conditions. Well-designed, prospective, multi-centre studies with standardized outcome measures are required to compare treatments.