Immunoglobulin treatment for severe childhood epilepsy

Current and emerging pharmacotherapy for the treatment of Lennox-Gastaut syndrome

INTRODUCTION

Lennox-Gastaut syndrome (LGS) is a severe childhood-onset epileptic encephalopathy, characterized by multiple seizure types, generalized slow spike-and-wave complexes in the EEG, and cognitive impairment. Seizures in LGS are typically resistant to treatment with antiseizure medications (ASMs). Tonic/atonic ('drop') seizures are of particular concern, due to their liability to cause physical injury.

AREAS COVERED

We summarize evidence for current and emerging ASMs for the treatment of seizures in LGS. The review focuses on findings from randomized, double-blind, placebo-controlled trials (RDBCTs). For ASMs for which no double-blind trials were identified, lower quality evidence was considered. Novel pharmacological agents currently undergoing investigation for the treatment of LGS are also briefly discussed.

EXPERT OPINION

Evidence from RDBCTs supports the use of cannabidiol, clobazam, felbamate, fenfluramine, lamotrigine, rufinamide, and topiramate as adjunct treatments for drop seizures. Percentage decreases in drop seizure frequency ranged from 68.3% with high-dose clobazam to 14.8% with topiramate. Valproate continues to be considered the first-line treatment, despite the absence of RDBCTs specifically in LGS. Most individuals with LGS will require treatment with multiple ASMs. Treatment decisions should be individualized and take into account adverse effects, comorbidities, general quality of life, and drug interactions, as well as individual efficacy.

A Systematic Review and Meta-Analysis of Immunoglobulin G Abnormalities and the Therapeutic Use of Intravenous Immunoglobulins (IVIG) in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder affecting approximately 2% of children in the United States. Growing evidence suggests that immune dysregulation is associated with ASD. One immunomodulatory treatment that has been studied in ASD is intravenous immunoglobulins (IVIG). This systematic review and meta-analysis examined the studies which assessed immunoglobulin G (IgG) concentrations and the therapeutic use of IVIG for individuals with ASD. Twelve studies that examined IgG levels suggested abnormalities in total IgG and IgG 4 subclass concentrations, with concentrations in these IgGs related to aberrant behavior and social impairments, respectively. Meta-analysis supported possible subsets of children with ASD with low total IgG and elevated IgG 4 subclass but also found significant variability among studies. A total of 27 publications reported treating individuals with ASD using IVIG, including four prospective, controlled studies (one was a double-blind, placebo-controlled study); six prospective, uncontrolled studies; 2 retrospective, controlled studies; and 15 retrospective, uncontrolled studies. In some studies, clinical improvements were observed in communication, irritability, hyperactivity, cognition, attention, social interaction, eye contact, echolalia, speech, response to commands, drowsiness, decreased activity and in some cases, the complete resolution of ASD symptoms. Several studies reported some loss of these improvements when IVIG was stopped. Meta-analysis combining the aberrant behavior checklist outcome from two studies demonstrated that IVIG treatment was significantly associated with improvements in total aberrant behavior and irritability (with large effect sizes), and hyperactivity and social withdrawal (with medium effect sizes). Several studies reported improvements in pro-inflammatory cytokines (including TNF-alpha). Six studies reported improvements in seizures with IVIG (including patients with refractory seizures), with one study reporting a worsening of seizures when IVIG was stopped. Other studies demonstrated improvements in recurrent infections, appetite, weight gain, neuropathy, dysautonomia, and gastrointestinal symptoms. Adverse events were generally limited but included headaches, vomiting, worsening behaviors, anxiety, fever, nausea, fatigue, and rash. Many studies were limited by the lack of standardized objective outcome measures. IVIG is a promising and potentially effective treatment for symptoms in individuals with ASD; further research is needed to provide solid evidence of efficacy and determine the subset of children with ASD who may best respond to this treatment as well as to investigate biomarkers which might help identify responsive candidates.

The role of inflammatory mediators in epilepsy: Focus on developmental and epileptic encephalopathies and therapeutic implications

In recent years, there has been an increasing interest in the potential involvement of neuroinflammation in the pathogenesis of epilepsy. Specifically, the role of innate immunity (that includes cytokines and chemokines) has been extensively investigated either in animal models of epilepsy and in clinical settings. Developmental and epileptic encephalopathies (DEE) are a heterogeneous group of epileptic disorders, in which uncontrolled epileptic activity results in cognitive, motor and behavioral impairment. By definition, epilepsy in DEE is poorly controlled by common antiepileptic drugs but may respond to alternative treatments, including steroids and immunomodulatory drugs. In this review, we will focus on how cytokines and chemokines play a role in the pathogenesis of DEE and why expanding our knowledge about the role of neuroinflammation in DEE may be crucial to develop new and effective targeted therapeutic strategies to prevent seizure recurrence and developmental regression.

Immunotherapy for GRIN2A and GRIN2D-related epileptic encephalopathy

BACKGROUND

GRIN-related developmental-epileptic encephalopathies are associated with a spectrum of neurodevelopmental disorders, including intellectual disability, epilepsy including continuous spike-and-wave during sleep syndrome (CSWS), or epilepsy-aphasia spectrum phenotypes such as in Landau-Kleffner syndrome. Efficacy of IVIG treatment was recently reported in a patient with LKS related to GRIN2A mutation.

AIM AND METHODS

We describe the efficacy of Immunotherapy in 5 consecutive patients (4 males, age range 6 months-13 years) with molecularly confirmed GRIN-related epileptic encephalopathy (4 with GRIN2A- related epilepsy-aphasia spectrum/epileptic encephalopathy with CSWS, accompanied by verbal, communicative and behavioural regression, and one patient with GRIN2D - related infantile developmental-epileptic encephalopathy). All patients had global developmental delay/ intellectual disability in various degrees, and were resistant to anticonvulsants, but none of the patients had frequent clinical seizures. All patients received monthly infusion of IVIG 2 g/ kg for 6 months; 2 patients were also treated with high-dose corticosteroids.

RESULTS

Normalization or near normalization of the EEG was noted in 3 patients, from whom 2 had mild improvement in verbal abilities and communication skills. Perceptual/spatial abilities, as well as executive functions and attention span, remained significantly impaired.

CONCLUSION

according to this preliminary, open-label study, Immunotherapy may lead to a clinical and electrographic improvement in patients with GRIN-related developmental-epileptic encephalopathies. Further studies to validate the efficacy of immunotherapy and the potential role of autoimmunity in GRIN-related disorders are needed.

Intravenous immunoglobulins for epilepsy

BACKGROUND

Epilepsy is a common neurological condition, with an estimated incidence of 50 per 100,000 persons. People with epilepsy may present with various types of immunological abnormalities, such as low serum immunoglobulin A (IgA) levels, lack of the immunoglobulin G (IgG) subclass and identification of certain types of antibodies. Intravenous immunoglobulin (IVIg) treatment may represent a valuable approach and its efficacy has important implications for epilepsy management. This is an update of a Cochrane review first published in 2011 and last updated in 2017.

OBJECTIVES

To examine the effects of IVIg on the frequency and duration of seizures, quality of life and adverse effects when used as monotherapy or as add-on treatment for people with epilepsy.

SEARCH METHODS

For the latest update, we searched the Cochrane Register of Studies (CRS Web) (20 December 2018), MEDLINE (Ovid, 1946 to 20 December 2018), Web of Science (1898 to 20 December 2018), ISRCTN registry (20 December 2018), WHO International Clinical Trials Registry Platform (ICTRP, 20 December 2018), the US National Institutes of Health ClinicalTrials.gov (20 December 2018), and reference lists of articles.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of IVIg as monotherapy or add-on treatment in people with epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the trials for inclusion and extracted data. We contacted study authors for additional information. Outcomes included percentage of people rendered seizure-free, 50% or greater reduction in seizure frequency, adverse effects, treatment withdrawal and quality of life.

MAIN RESULTS

We included one study (61 participants). The included study was a randomised, double-blind, placebo-controlled, multicentre trial which compared the treatment efficacy of IVIg as an add-on with a placebo add-on in patients with drug-resistant epilepsy. Seizure freedom was not reported in the study. There was no significant difference between IVIg and placebo in 50% or greater reduction in seizure frequency (RR 1.89, 95% CI 0.85 to 4.21; one study, 58 participants; low-certainty evidence). The study reported a statistically significant effect for global assessment in favour of IVIg (RR 3.29, 95% CI 1.13 to 9.57; one study, 60 participants; low-certainty evidence). No adverse effects were demonstrated. We found no randomised controlled trials that investigated the effects of IVIg monotherapy for epilepsy. Overall, the included study was rated at low to unclear risk of bias. Using GRADE methodology, the certainty of the evidence was rated as low.

AUTHORS' CONCLUSIONS

We cannot draw any reliable conclusions regarding the efficacy of IVIg as a treatment for epilepsy. Further randomised controlled trials are needed.

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.

Intravenous immunoglobulin G as adjuvant treatment in drug-resistant childhood epilepsy

BACKGROUND

Epilepsy is the most common neurological disease in childhood; depending on the definition of drug-resistant epilepsy, incidence varies from 10% to 23% in the paediatric population. The objective of this study was to account for the decrease in the frequency and/or monthly duration of epileptic seizures in paediatric patients with drug-resistant epilepsy treated with antiepileptic drugs, before and after adding intravenous immunoglobulin G (iIV IgG).

METHODS

This is an analytic, observational, retrospective case-control study. We studied paediatric patients with drug-resistant epilepsy who were treated with IV IgG at the Centro Médico Nacional 20 de Noviembre, in Mexico City, from 2003 to 2013.

RESULTS

One hundred and sixty seven patients (19.5%) had drug-resistant epilepsy and 44 (5.1%) started adjuvant treatment with IV IgG. The mean age of patients at the beginning of treatment was 6.12 years±5.14); aetiology was structural acquired in 28 patients (73.6%), genetic in 5 (13.1%), immune in 1 (2.6%), and unknown in 4 (10.5%). At 2 months from starting IV IgG, seizure duration had reduced to 66.66%; the frequency of seizures was reduced by 64% at 4 months after starting treatment (P<.001).

CONCLUSIONS

According to the results of this study, intravenous immunoglobulin may be an effective therapy for reducing the frequency and duration of seizures in paediatric patients with drug-resistant epilepsy.

Intravenous immunoglobulins for epilepsy

BACKGROUND

Epilepsy is a common neurological condition, with an estimated incidence of 50 per 100,000 persons. People with epilepsy may present with various types of immunological abnormalities, such as low serum immunoglobulin A (IgA) levels, lack of the immunoglobulin G (IgG) subclass and identification of certain types of antibodies. Intravenous immunoglobulin (IVIg) treatment may represent a valuable approach and its efficacy has important implications for epilepsy management. This is an updated version of the original Cochrane review published in Issue 1, 2011.

OBJECTIVES

To examine the effects of IVIg on the frequency and duration of seizures, quality of life and adverse effects when used as monotherapy or as add-on treatment for people with epilepsy.

SEARCH METHODS

For the latest update, we searched the Cochrane Epilepsy Group Specialized Register (2 February 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (2 February 2017), MEDLINE (Ovid, 1946 to 2 February 2017), Web of Science (1898 to 2 February 2017), ISRCTN registry (2 February 2017), WHO International Clinical Trials Registry Platform (ICTRP, 2 February 2017), the US National Institutes of Health ClinicalTrials.gov (2 February 2017), and reference lists of articles.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials of IVIg as monotherapy or add-on treatment in people with epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the trials for inclusion and extracted data. We contacted study authors for additional information. Outcomes included percentage of people rendered seizure-free, 50% or greater reduction in seizure frequency, adverse effects, treatment withdrawal and quality of life.

MAIN RESULTS

We included one study (61 participants). The included study was a randomized, double-blind, placebo-controlled, multi-centre trial which compared the treatment efficacy of IVIg as an add-on with a placebo add-on in patients with refractory epilepsy. There was no significant difference between IVIg and placebo in 50% or greater reduction in seizure frequency. The study reported a statistically significant effect for global assessment in favour of IVIg. No adverse effects were demonstrated. We found no randomized controlled trials that investigated the effects of IVIg monotherapy for epilepsy. Overall, the included study was rated as low/unclear risk of bias. Using GRADE methodology, the quality of the evidence was rated as low.

AUTHORS' CONCLUSIONS

We cannot draw any reliable conclusions regarding the efficacy of IVIg as a treatment for epilepsy. Further randomized controlled trials are needed.

Impact of Immunoglobulin Therapy in Pediatric Disease: a Review of Immune Mechanisms

Intravenous immunoglobulin (IVIG) provides replacement therapy in immunodeficiency and immunomodulatory therapy in inflammatory and autoimmune diseases. This paper describes the immune mechanisms underlying six major non-primary immunodeficiency pediatric diseases and the diverse immunomodulatory functions of IVIG therapy. In Kawasaki disease, IVIG plays a major, proven, and effective role in decreasing aneurysm formation, which represents an aberrant inflammatory response to an infectious trigger in a genetically predisposed individual. In immune thrombocytopenia, IVIG targets the underlying increased platelet destruction and decreased platelet production. Although theoretically promising, IVIG shows no clear clinical benefit in the prophylaxis and treatment of neonatal sepsis. Limitations in research design combined with the unique neonatal immunologic environment offer explanations for this finding. Inflammation from aberrant immune activation underlies the myelinotoxic effects of Guillain-Barré syndrome. HIV-1 exerts a broad range of immunologic effects and was found to decrease serious bacterial infections in the pre-highly active anti-retroviral therapy (HAART) era, although its practical relevance in the post-HAART era has waned. Clinical and experimental data support the role of immune mechanisms in the pathogenesis of childhood epilepsy. IVIG exerts anti-epileptic effects through targeting upregulated cytokine pathways and antibodies thought to contribute to epilepsy. Applications in six additional pediatric diseases including pediatric asthma, atopic dermatitis, cystic fibrosis, pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS), autism, and transplantation will also be briefly reviewed. From autoimmunity to immunodeficiency, a dynamic immunologic basis underlies major pediatric diseases and highlights the broad potential of IVIG therapy.

Intravenous immunoglobulin therapy is rarely effective as the initial treatment in West syndrome: A retrospective study of 70 patients

PURPOSE

To evaluate factors influencing the efficacy and safety of intravenous immunoglobulins (IVIG) therapy for West syndrome.

METHODS

We investigated seizure outcomes in 70 patients who received IVIG treatment for West Syndrome during the first 3months after the onset of epileptic spasms. IVIG was administered for 3 consecutive days (initial IVIG treatment) at dosages ranging from 100 to 500mg/kg/day. If spasms disappeared within 2weeks of the initial treatment, maintenance IVIG treatment was commenced. We evaluated seizure outcomes at 2weeks (initial evaluation), at 2years (long-term evaluation), and the last visit (last follow-up evaluation) after the initial IVIG treatment. We analyzed dosages of IVIG, age at onset of spasms, treatment lag, and etiologies between responders and non-responders.

RESULTS

Among the patients, 7/70 (10.0%) had cessation of spasms and resolution of hypsarrhythmia at the initial evaluation. Another 6/70 patients (8.6%) were found to have cessation of spasms at the long-term evaluations. The treatment lag in responders was shorter than that in non-responders (P<0.01). There were no significant differences between responders and non-responders in IVIG dosages, age at onset of spasms, and etiologies. Two patients had relapse of partial seizures after cessation of spasms at the last follow-up evaluation. Adverse effects occurred in 2/70 patients.

CONCLUSIONS

The efficacy of IVIG was so low that it should not be considered as first-line treatment in West syndrome. IVIG therapy has a good safety profile and we would recommend it for West syndrome cases with drug resistance, severe complications associated with profound brain damage, severe brain atrophy, and in immunocompromised patients.

Status epilepticus and refractory status epilepticus management

Status epilepticus (SE) describes persistent or recurring seizures without a return to baseline mental status and is a common neurologic emergency. SE can occur in the context of epilepsy or may be symptomatic of a wide range of underlying etiologies. The clinician's aim is to rapidly institute care that simultaneously stabilizes the patient medically, identifies and manages any precipitant conditions, and terminates seizures. Seizure management involves "emergent" treatment with benzodiazepines followed by "urgent" therapy with other antiseizure medications. If seizures persist, then refractory SE is diagnosed and management options include additional antiseizure medications or infusions of midazolam or pentobarbital. This article reviews the management of pediatric SE and refractory SE.

Generalized epilepsies: immunologic and inflammatory mechanisms

This article focuses on the inflammatory processes in patients with generalized epilepsies. We specifically review the data regarding West, Lennox-Gastaut, and Landau-Kleffner syndromes as they have generalized clinical or electroencephalogram features. There is substantial evidence for a pathogenic implication of immune mechanisms in these epilepsies. Animal models and abnormalities in both cellular and humoral immunity support this hypothesis. They also appear to be particularly responsive to immunomodulatory therapies, which has raised the speculation that an unbalanced immune system may play an important role in the pathophysiology of these epileptic syndromes. In this article, we discuss clinical and experimental data that support the potential implication of immune mediated inflammation and immune response in the mechanism of these entities.

An effective initial polytherapy for children with West syndrome

Adrenocorticotropic hormone is recommended worldwide as an initial therapy for infantile spasms. However, infantile spasms in about 50% of children cannot be fully controlled by adrenocorticotropic hormone monotherapy, seizures recur in 33% of patients who initially respond to adrenocorticotropic hormone monotherapy, and side effects are relatively common during adrenocorticotropic hormone treatment. Topiramate, vitamin B₆, and immunoglobulin are effective in some children with infantile spasms. In the present study, we hypothesized that combined therapy with adrenocorticotropic hormone, topiramate, vitamin B₆, and immunoglobulin would effectively treat infantile spasms and have mild adverse effects. Thus, 51 children newly diagnosed with West syndrome including infantile spasms were enrolled and underwent polytherapy with the four drugs. Electroencephalographic hypsarrhythmia was significantly improved in a majority of patients, and these patients were seizure-free, had mild side effects, and low recurrence rates. The overall rates of effective treatment and loss of seizures were significantly higher in cryptogenic children compared with symptomatic children. The mean time to loss of seizures in cryptogenic children was significantly shorter than in symptomatic patients. These findings indicate that initial polytherapy with adrenocorticotropic hormone, topiramate, vitamin B₆, and immunoglobulin effectively improves the prognosis of infantile spasms, and its effects were superior in cryptogenic children to symptomatic children.