Rasmussen's syndrome: progressive autoimmune multi-focal encephalopathy

Case Report: Molecular Analyses of Cell-Cycle-Related Genes in Cortical Brain Tissue of a Patient with Rasmussen Encephalitis

Rasmussen's encephalitis (RE) stands as a rare neurological disorder marked by progressive cerebral hemiatrophy and epilepsy resistant to medical treatment. Despite extensive study, the primary cause of RE remains elusive, while its histopathological features encompass cortical inflammation, neuronal degeneration, and gliosis. The underlying molecular mechanisms driving disease progression remain largely unexplored. In this case study, we present a patient with RE who underwent hemispherotomy and has remained seizure-free for over six months, experiencing gradual motor improvement. Furthermore, we conducted molecular analysis on the excised brain tissue, unveiling a decrease in the expression of cell-cycle-associated genes coupled with elevated levels of BDNF and TNF-α proteins. These findings suggest the potential involvement of cell cycle regulators in the progression of RE.

A Case Report of a Positive Antinuclear Ribonucleoprotein Antibody, a Weak-Positive Antinuclear Antibody, Elevated C3 Complement, and Possibly Trauma-Induced Rasmussen's Encephalitis

A case of a late-onset Rasmussen's encephalitis (RE) presenting with drug-refractory focal epilepsy and progressive hemispheric cerebral atrophy noted on a serial radiologic head scan done on a gentleman in his 30s is presented. A positive antinuclear ribonucleoprotein antibody test, a weak-positive antinuclear antibody test, an elevated C3 complement, and possible trauma were identified as potential causative or promoting factors for RE in this patient. Literature evidence regarding the challenges with the aetiopathogenesis description, diagnosis, and management of this rare condition has been reviewed in this article. Exploring an aetiological-based diagnosis of this condition could open research and interventional opportunities into aetiology-guided management opportunities in this condition.

Febrile infection-related Epilepsy Syndrome (FIRES): a severe encephalopathy with status epilepticus. Literature review and presentation of two new cases

FIRES is defined as a disorder that requires a prior febrile infection starting between 2 weeks and 24 h before the onset of the refractory status epilepticus with or without fever at the onset of status epilepticus. The patients, previously normal, present in the acute phase recurrent seizures and status epilepticus followed by a severe course with usually persistent seizures and residual cognitive impairment. Boundary with "new onset refractory status epilepticus (NORSE) has not clearly established. Pathogenetic hypothesis includes inflammatory or autoimmune mechanism with a possible genetic predisposition for an immune response dysfunction.Various types of treatment have been proposed for the treatment of the acute phase of the disorder to block the rapid seizures evolution to status epilepticus and to treat status epilepticus itself. Prognosis is usually severe both for control of the seizures and for cognitive involvement.FIRES is an uncommon but severe disorder which must be carefully considered in the differential diagnosis with other epileptic encephalopathy.

Diagnosis and treatment of Rasmussen's encephalitis pose a big challenge: Two case reports and literature review

Rasmussen encephalitis (RE) is a rare disease of unknown etiology that causes severe chronic unihemispheric inflammatory disease of the central nervous system mainly in children. It leads to intractable seizures, cognitive decline and progressive neurological deficits in the affected hemisphere.

We report two cases of RE, as defined by fulfillment of the 2005 Bien criteria. The diagnostic challenge of characterizing this rare disease will be highlighted by the extensive serum, CSF, MR imaging and EEG data in the two patients. In addition, we will review the various forms of therapy attempted in these two patients, namely anti-epileptic drug therapy and immunomodulatory therapy. Hemispherectomy was done for the second patient with favorable outcomes of controlling seizures, but unfortunately, he died because of meningitis.

Until the causes of Rasmussen's encephalitis are known, it is difficult to anticipate how treatments will improve. Such a situation creates a therapeutic dilemma; hemispherectomy is not favored because of the inevitable postoperative functional deficits, but a real risk exists that treatments used to delay progression of the disease will defer definitive surgical treatment beyond the time when an optimum post-hemispherectomy outcome could be expected.

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Rasmussen encephalitis (RE) causes severe chronic unihemispheric inflammatory disease.

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RE should be suspected in any patient with refractory seizures.

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Its recognition is important because early intervention with surgery can improve outcomes.

Intrathecal Infusion of Autologous Adipose-Derived Regenerative Cells in Autoimmune Refractory Epilepsy: Evaluation of Safety and Efficacy

Objective/Purpose. Evaluation of efficacy and safety of autologous adipose-derived regenerative cells (ADRCs) treatment in autoimmune refractory epilepsy. Patients. Six patients with proven or probable autoimmune refractory epilepsy (2 with Rasmussen encephalitis, 2 with antineuronal autoantibodies in serum, and 2 with possible FIRES) were included in the project with approval of the Bioethics Committee.

Encefalitis de Rasmussen diagnóstico y enfoque terapéutico

Objetivo: describir el caso de una paciente escolar con diagnóstico de encefalitis de Rasmussen de presentación aguda y el enfoque terapéutico. Presentación: paciente femenina de 5 años y nueve meses que cursa con cuadro de evolución progresiva caracterizado por posturas distónicas que se inicia en pierna izquierda seguida de miembro superior ipsilateral asociadas con crisis focales con semiología de inicio opercular que la conducen a estatus epiléptico. La  resonancia magnética cerebral evidencia cambios estructurales progresivos con atrofia hemisférica y del núcleo basal derechos, se inicia terapia antiepiléptica e inmunomoduladora  con buena respuesta. Discusión: se realizó una revisión de la literatura sobre la presentación clínica, diagnóstico y mejores opciones terapéuticas. Conclusiones: se trata de una escolar con síndrome de Rasmussen en etapa aguda, con adecuada evolución clínica luego de inicio de inmunoterapia. En Colombia existen pocos reportes, nuestro propósito es realizar la presentación de un caso y revisar el enfoque diagnóstico y terapéutico.

A New Frontier: The Convergence of Nanotechnology, Brain Machine Interfaces, and Artificial Intelligence

A confluence of technological capabilities is creating an opportunity for machine learning and artificial intelligence (AI) to enable "smart" nanoengineered brain machine interfaces (BMI). This new generation of technologies will be able to communicate with the brain in ways that support contextual learning and adaptation to changing functional requirements. This applies to both invasive technologies aimed at restoring neurological function, as in the case of neural prosthesis, as well as non-invasive technologies enabled by signals such as electroencephalograph (EEG). Advances in computation, hardware, and algorithms that learn and adapt in a contextually dependent way will be able to leverage the capabilities that nanoengineering offers the design and functionality of BMI. We explore the enabling capabilities that these devices may exhibit, why they matter, and the state of the technologies necessary to build them. We also discuss a number of open technical challenges and problems that will need to be solved in order to achieve this.

Seizures and risk of epilepsy in autoimmune and other inflammatory encephalitis

PURPOSE OF REVIEW

The aim of this study was to assess the seizure manifestations and risk of epilepsy in encephalitis associated with antibodies against neuronal cell-surface (autoimmune encephalitis) or myelin-associated antigens, and to review several chronic epileptic disorders, including Rasmussen's encephalitis, fever-induced refractory epileptic syndromes (FIRES) and new-onset refractory status epilepticus (NORSE).

RECENT FINDINGS

Seizures are a frequent manifestation of autoimmune encephalitis. Some autoimmune encephalitis may associate with characteristic features: faciobrachial dystonic seizures (anti-LGI1 encephalitis), electroencephalogram extreme delta brush (anti-NMDAR) or multifocal FLAIR-MRI abnormalities (anti-GABAAR). In anti-LGI1 encephalitis, cortical, limbic and basal ganglia dysfunction results in different types of seizures. Autoimmune encephalitis or myelin-antibody associated syndromes are often immunotherapy-responsive and appear to have a low risk for chronic epilepsy. In contrast patients with seizures related to GAD65-antibodies (an intracellular antigen) frequently develop epilepsy and have suboptimal response to treatment (including surgery). Rasmussen's encephalitis or FIRES may occur with autoantibodies of unclear significance and rarely respond to immunotherapy. A study of patients with NORSE showed that 30% developed chronic epilepsy.

SUMMARY

Although seizures are frequent in all types of autoimmune encephalitis, the risk for chronic epilepsy is dependent on the antigen: lower if located on the cell-surface, and higher if intracellular. For other disorders (Rasmussen's encephalitis, FIRES, NORSE), the prognosis remains poor.

Autoimmune Epilepsies

Autoimmune epilepsies describe clinical syndromes wherein the immune system is suspected to be involved in the pathogenesis of seizures or as a mechanism for neuronal injury following seizures. These diseases typically affect otherwise healthy children and are characterized by explosive onset of focal seizures, encephalopathy, cognitive deterioration, or other focal neurological deficits, or all of these. Traditional neurological diagnostics lack sensitivity and specificity in the diagnosis of autoimmune epilepsies, and results must be considered in the clinical context. Consideration of an autoimmune etiology early in the clinical course is important to ensure timely initiation of immunotherapy, as appropriate, as conventional antiepileptic drugs alone are typically unable to control seizures and other neurological symptoms. This article discusses the autoimmune epilepsies of autoimmune encephalitis (including anti-N-methyl-D-aspartate receptor encephalitis), Rasmussen's encephalitis, and febrile infection-related epilepsy syndrome. Further research is needed to better understand pathogenic mechanisms, optimal immunotherapy, and the effect of treatment on prognosis.

What Elements of the Inflammatory System Are Necessary for Epileptogenesis In Vitro?

The inflammatory and central nervous systems share many signaling molecules, compromising the utility of traditional pharmacological and knockout approaches in defining the role of inflammation in CNS disorders such as epilepsy. In an in vitro model of post-traumatic epileptogenesis, the development of epilepsy proceeded in the absence of the systemic inflammatory system, and was unaffected by removal of cellular mediators of inflammation, including macrophages and T-lymphocytes.

Epileptogenesis in vivo can be altered by manipulation of molecules such as cytokines and complement that subserve intercellular signaling in both the inflammatory and central nervous systems. Because of the dual roles of these signaling molecules, it has been difficult to precisely define the role of systemic inflammation in epileptogenesis. Organotypic hippocampal brain slices can be maintained in culture independently of the systemic inflammatory system, and the rapid course of epileptogenesis in these cultures supports the idea that inflammation is not necessary for epilepsy. However, this preparation still retains key cellular inflammatory mediators. Here, we found that rodent hippocampal organotypic slice cultures depleted of T lymphocytes and microglia developed epileptic activity at essentially the same rate and to similar degrees of severity as matched control slice cultures. These data support the idea that although the inflammatory system, neurons, and glia share key intercellular signaling molecules, neither systemic nor CNS-specific cellular elements of the immune and inflammatory systems are necessary components of epileptogenesis.

Early Treatment of a Progressive Rasmussen's Like Syndrome with Ganciclovir

Background:

Escalating focal sensorimotor seizures, progressive neurologic deficit and cognitive decline with associated typical magnetic resonance imaging (MRI) findings or pathological confirmation constitute the syndrome of Rasmussen's encephalitis.

Methods:

Three patients with this clinical scenario had long-term follow-up after being given the antiviral drug ganciclovir 10 mg/kg/day IV for ten days within one to three months of disease onset.

Results:

Seizures occurred at least hourly and were localized to the Rolandic region. The MRIs were normal in one patient and in two showed changes consistent with ongoing seizures. Two patients, one whose short-term outcome was reported previously, had immediate and sustained cessation of seizures and resolution of their neurologic deficit. One patient with seizures from both hemispheres did not respond and went on to hemispherectomy that confirmed chronic encephalitis. Seizures continued in five other patients treated 6 to 72 months after disease onset.

Conclusion:

The sustained seizure control after ganciclovir in two of three patients suggests this drug may be effective when given early in the course of this subacute intractable focal epilepsy syndrome.

Mechanisms of epileptogenesis in pediatric epileptic syndromes: Rasmussen encephalitis, infantile spasms, and febrile infection-related epilepsy syndrome (FIRES)

The mechanisms of epileptogenesis in pediatric epileptic syndromes are diverse, and may involve disturbances of neurodevelopmental trajectories, synaptic homeostasis, and cortical connectivity, which may occur during brain development, early infancy, or childhood. Although genetic or structural/metabolic factors are frequently associated with age-specific epileptic syndromes, such as infantile spasms and West syndrome, other syndromes may be determined by the effect of immunopathogenic mechanisms or energy-dependent processes in response to environmental challenges, such as infections or fever in normally-developed children during early or late childhood. Immune-mediated mechanisms have been suggested in selected pediatric epileptic syndromes in which acute and rapidly progressive encephalopathies preceded by fever and/or infections, such as febrile infection-related epilepsy syndrome, or in chronic progressive encephalopathies, such as Rasmussen encephalitis. A definite involvement of adaptive and innate immune mechanisms driven by cytotoxic CD8(+) T lymphocytes and neuroglial responses has been demonstrated in Rasmussen encephalitis, although the triggering factor of these responses remains unknown. Although the beneficial response to steroids and adrenocorticotropic hormone of infantile spasms, or preceding fever or infection in FIRES, may support a potential role of neuroinflammation as pathogenic factor, no definite demonstration of such involvement has been achieved, and genetic or metabolic factors are suspected. A major challenge for the future is discovering pathogenic mechanisms and etiological factors that facilitate the introduction of novel targets for drug intervention aimed at interfering with the disease mechanisms, therefore providing putative disease-modifying treatments in these pediatric epileptic syndromes.

Inflammasome induction in Rasmussen's encephalitis: cortical and associated white matter pathogenesis

Background

Rasmussen’s encephalitis (RE) is an inflammatory encephalopathy of unknown cause defined by seizures with progressive neurological disabilities. Herein, the pathogenesis of RE was investigated focusing on inflammasome activation in the brain.

Methods

Patients with RE at the University of Alberta, Edmonton, AB, Canada, were identified and analyzed by neuroimaging, neuropsychological, molecular, and pathological tools. Primary human microglia, astrocytes, and neurons were examined using RT-PCR, enzyme-linked immunosorbent assay (ELISA), and western blotting.

Results

Four patients with RE were identified at the University of Alberta. Magnetic resonance imaging (MRI) disclosed increased signal intensities in cerebral white matter adjacent to cortical lesions of RE patients, accompanied by a decline in neurocognitive processing speed (P <0.05). CD3ϵ, HLA-DRA, and TNFα together with several inflammasome-associated genes (IL-1β, IL-18, NLRP1, NLRP3, and CASP1) showed increased transcript levels in RE brains compared to non-RE controls (n = 6; P <0.05). Cultured human microglia displayed expression of inflammasome-associated genes and responded to inflammasome activators by releasing IL-1β, which was inhibited by the caspase inhibitor, zVAD-fmk. Major histocompatibility complex (MHC) class II, IL-1β, caspase-1, and alanine/serine/cysteine (ASC) immunoreactivity were increased in RE brain tissues, especially in white matter myeloid cells, in conjunction with mononuclear cell infiltration and gliosis. Neuroinflammation in RE brains was present in both white matter and adjacent cortex with associated induction of inflammasome components, which was correlated with neuroimaging and neuropsychological deficits.

Conclusion

Inflammasome activation likely contributes to the disease process underlying RE and offers a mechanistic target for future therapeutic interventions.

Neuropathology of Seizure Disorders

Epilepsy is a common neurological disorder characterized by an enduring predisposition to generate recurrent seizures. Pathologists may be called upon to evaluate brain tissue from patients with a history of seizures, and it is important to keep in mind the diversity of histopathologic findings associated with this disorder and the limitations imposed by both, limited sampling and neuroanatomy. Review of the literature has shown that the three most common clinicopathological entities in surgically resected medically refractory epilepsy are mesial temporal sclerosis (MTS), long-term epilepsy-associated tumors (LEAT), and malformations of cortical development (MCD) which includes focal cortical dysplasia (FCD). Here, we will review the most common clinicopathological entities seen in surgically resected cases of refractory epilepsy, such as MTS, MCD, LEAT, as well as vascular and encephalitic lesions. We will also touch upon traumatic brain injuries and SUDEP, and the role of the forensic pathologist. A better understanding of the etiopathology, recent classifications, and underlying molecular mechanisms involved in each entity will be helpful in order to identify the cause of death in patients with seizure disorders, candidates who will benefit from tailored surgical resection strategies, as well as to develop new and targeted drug treatment.

Updated assessment of the prevalence, spectrum and case definition of autoimmune disease

Autoimmune diseases are heterogeneous with regard to prevalence, manifestations, and pathogenesis. The classification of autoimmune diseases has varied over time. Here, we have compiled a comprehensive up-to-date list of the autoimmune diseases, and have reviewed published literature to estimate their prevalence. We identified 81 autoimmune diseases. The overall estimated prevalence is 4.5%, with 2.7% for males and 6.4% for females. For specific diseases, prevalence ranges from 1% to <1/10(6). Considering all diseases in the class, the most common mean age-of-onset was 40-50 years. This list of autoimmune diseases has also yielded information about autoantigens. Forty-five autoimmune diseases have been associated with well-defined autoantigens. Of the diseases with known autoantigens, 33.3% had highly repetitive sequences, 35.6% had coiled-coil arrangements and 57.8% were associated with cellular membranes, which means that based on these structural motifs alone, autoantigens do not appear to be a random sample of the human proteome. Finally, we identified 19 autoimmune diseases that phenocopy diseases arising from germline mutations in the corresponding autoantigen. Collectively, our findings lead to a tentative proposal for criteria for assigning autoimmune pathogenesis to a particular disease.

Eponym : Rasmussen syndrome

Rasmussen's syndrome (RS) is a rare acquired progressive inflammatory encephalopathy characterized by drug-resistant partial seizures and cognitive deterioration resulting from a gradual impairment and a subsequent atrophy of a single brain hemisphere. It was firstly described by Theodore Rasmussen in 1958. The original etiopathogenic hypothesis of a chronic viral infection no longer holds. Today, the presumed mechanism is a complex autoimmune process comprising an active role of both cytotoxic T lymphocytes and circulating autoantibodies, activating the subunit 3 of the ionotropic glutamate receptor (GluR3Ab). Several medical options, such as antiepileptic drugs and immunomodulatory therapies, deserve consideration to face epileptic manifestations and to slow neurologic regression. Yet, all these therapies turn out to be almost always just temporizing measures. Surgical disconnection of the affected hemisphere ("functional hemispherectomy") is the best therapeutic choice to achieve the arrest of the disease, a good seizure control, the block of neurologic decline, and the improvement of patient's quality of life.

Nationwide survey (incidence, clinical course, prognosis) of Rasmussen's encephalitis

PURPOSE

Rasmussen's encephalitis (RE) is a progressive and catastrophic epileptic disorder caused by chronic localized encephalitis. We performed a nationwide survey of RE to assess the clinical picture, treatment effect, and prognosis of Japanese RE patients.

SUBJECTS & METHODS

The subjects were 27 patients (male:12; female:15) from 13 medical facilities. All of them satisfied the clinical and neuroimaging criteria for RE, including 14 pathologically proven cases.

RESULTS

They were divided into the childhood-onset rapidly progressive type (CORP, n=19), and late-onset slowly progressive type (LOSP, n=8). The mean age at epilepsy onset was 4 years and 4 months in CORP, and 16 years in LOSP. The mean period between the onset age of epilepsy and development of frequent seizures was 1 year and 4 months in the former, and 3 years and 4 months in the latter. The immunomodulatory treatment including high-dose steroid (n=14) and high-dose intravenous immunoglobulin therapies (IVIgG, n=12) achieved more than a 50% reduction in the seizure frequency in 5 (36%) and 4 (33%) patients, respectively. Eight and seven patients underwent focal cortical resection and functional hemispherectomy, leading to significant improvement in 5 of the 8 patients and excellent seizure control in all 7 patients, respectively.

CONCLUSION

Although the high-dose steroid and IVIG therapies may have alleviated the exacerbation of seizures in those with RE, they could not halt the disease progression. Functional hemispherectomy is still the only curative therapy for RE, despite the fact that the early introduction of this procedure remains controversial.

Sensorimotor function and sensorimotor tracts after hemispherectomy

Hemispherectomy is currently the only effective treatment for relieving constant seizures in children with severe or progressive unilateral cortical disease. Although early hemispherectomy has been advocated to avoid general dysfunction due to continued seizures, it remains unclear whether age at surgery affects specific sensorimotor functions. Little is know about the anatomical status of sensorimotor pathways after hemispherectomy and how it might relate to sensorimotor function. Here we measured motor function and sensory thresholds of the upper and lower limbs in 12 hemispherectomized patients. Diffusion tensor imaging (DTI) was used to determine status of brainstem corticospinal tracts and medial lemniscus. Hemispherectomy subjects showed remarkable recovery in both sensory and motor function. Many patients showed normal sensory vibration thresholds. Within the smaller Rasmussen's subgroup, we saw a relationship between age at surgery and sensorimotor function recovery (i.e. earlier was better). Anatomically, we found marked asymmetry in brainstem corticospinal tracts but preserved symmetry in the medial lemniscus, which may relate to robust sensory recovery. Age at surgery predicted anatomical status of brainstem sensorimotor tracts. In sum, we found that age at surgery influences anatomical changes in brainstem motor pathways, and may also relate to sensorimotor recovery patterns.

Finding on brain MRI mimicking focal cortical dysplasia in early Rasmussen's encephalitis: a case report and review

INTRODUCTION

Rasmussen's encephalitis (RE) is one of the important causes of refractory seizure. The most impressive clinical manifestation of RE is epilepsia partialis continua (EPC). Others include progressive hemiparesis and neuropsychological deterioration. Currently, the best approach to RE is hemispherectomy.

CASE HISTORIES

We describe a patient whose clinical manifestations were compatible with RE; however, the initial brain MRI was interpreted as focal cortical dysplasia over right parietal region.

DISCUSSION

The follow-up brain MRI 1 year later showed diffuse atrophy of the brain with more atrophic change in right hemisphere, and the EPC disappeared after right hemispherectomy.

Rasmussen syndrome combined with IgA deficiency and membranous nephropathy

A 9-year-old boy diagnosed as having Rasmussen syndrome had congenital IgA deficiency and juvenile alopecia. He developed auditory hallucination and consciousness disturbance with intractable complex partial epileptic status. Anti-glutamate receptor epsilon2 antibodies were detected in his serum and cerebrospinal fluid. He was administered immunomodulatory agents and his seizures were treated with an intravenous anticonvulsant for 2 months. Subsequently, he developed a nephrotic syndrome, which proved to be membranous nephropathy and was treated with cyclophosphamide. Anti-basement membrane antibodies were detected in his serum. The boy died at the age of 14 years, and autopsy revealed diffuse brain atrophy with neuronal loss, infiltration of glial cells in the cerebrum, and loss of Purkinje cells in the cerebellum. A kidney specimen contained many sclerotic glomeruli, indicative of progressive membranous nephropathy. The patient was considered to have multimodal autoimmune disorder producing juvenile alopecia, autoimmune encephalitis, and a membranous nephropathy, based on the congenital IgA deficiency.

Increased activation of Iba1+ microglia in pediatric epilepsy patients with Rasmussen's encephalitis compared with cortical dysplasia and tuberous sclerosis complex

Microgliosis is prominent in Rasmussen's encephalitis (RE), a disease with severe seizure activity. However, it is unclear if microglial activation is similar with different histopathologic substrates. Iba1-immunolabelled microglial activation was assessed in neocortex from pediatric epilepsy surgery patients with RE (n=8), cortical dysplasia (CD; n=6) and tuberous sclerosis complex (TSC; n=6). Microglial reactivity was increased, in severely affected RE areas (29% labeling) compared with minimally affected areas of RE cases (15%) and cases of TSC (14%) and CD (12%). There was no qualitative association of Iba1 immunolabelling with the presence of CD8(+) cytotoxic T-cells and no statistical association with clinical epilepsy variables, such as seizure duration or frequency. Iba1 appears to be an excellent marker for detecting extensive microglial activation in patients with RE. In addition, this study supports the notion that Iba1-labeled microglial activation is increased in patients with active RE, compared with cases of CD and TSC.

Cortical Resection Tailored to Awake, Intraoperative Ictal Recordings and Motor Mapping in the Treatment of Intractable Epilepsia Partialis Continua: Technical Case Report

Objective:

Epilepsia partialis continua (EPC) is a form of status epilepticus that is characterized by continuous simple partial seizures and can occur as a manifestation of a variety of underlying pathological processes. Because these seizures typically take onset within or close to motor cortex, the treatment of refractory EPC with resective surgery risks significant postoperative deficits.

Clinical Presentation:

We describe our experience using ictal recordings obtained intraoperatively during awake craniotomy, in conjunction with direct cortical stimulation mapping, to tailor surgical resections in 2 patients with refractory EPC. Both patients had pan-hemispheric pathologies that made extraoperative recording difficult.

Intervention:

Awake craniotomy takes advantage of a unique feature of refractory EPC, namely the near-continuous presence of focal seizure activity. It allows the surgeon to record seizures in the operating room and precisely define the anatomic location of epileptic activity, to resect the seizure focus, and to both visually and electrographically confirm successful cessation of EPC after resection, all within a single operation. We used standard methods of awake craniotomy to finely tailor a cortical resection to the epileptogenic cortex while sparing nearby eloquent motor areas. The precision of awake mapping made this approach safe and effective.

Conclusion:

The cases we describe demonstrate the role of focal resection in the treatment of EPC. Standard techniques of awake craniotomy have application in the treatment of this challenging problem.

Quantification of antineural antibodies in autoimmune neurological disorders

More than 50 different neurological pathologies have a confirmed or suspected autoimmune etiology affecting an estimated number of 75 million people worldwide. Autoantibodies are a useful diagnostic marker for most autoimmune diseases even though their pathological role is not evident, and several tests for their detection are commercially available. However, for autoimmune diseases involving the nervous system, lack of clear information on the identity of antineural antibody targets and the presence of many rare diseases have hampered the development of specific diagnostic assays. This review focuses on the actual knowledge on confirmed and suspected autoimmune diseases that target the CNS and the diagnostic relevance of corresponding antineural autoantibodies.

A case of unilateral hemispheric encephalitis

Herein we report a case of encephalitis involving the unilateral hemisphere, with a clinical course different from that of Rasmussen syndrome. A 44-year-old man visited us because of headache and language abnormality. Cerebrospinal fluid examination showed lymphocytosis with increased level of protein. Brain MRI showed abnormal findings limited to the unilateral hemisphere. The symptoms and signs improved without any specific antiviral treatment in a week. However, language disturbance and right hemiparesis developed after a week. Steroid therapy was effective. He recovered without any neurologic sequelae. Our case was unusual encephalitis involving the unilateral hemisphere, which was benign and steroid-responsive.

IVIG therapy in neurological disorders of childhood

There is growing evidence that intravenous immunoglobulins (IVIG) are effective in some neuroimmunological disorders of childhood. This short review summarizes the evidence-based indications and recommendations of IVIG therapy in these disorders. Despite considerable efforts to define the role and mechanisms of IVIG, more clinical studies are needed to further explore the therapeutic potential of IVIG in childhood diseases of the nervous system and muscle.

Greyhound meningoencephalitis: PCR-based detection methods highlight an absence of the most likely primary inducing agents

Greyhound meningoencephalitis is currently classified as a breed-associated idiopathic central nervous system inflammatory disorder. The non-suppurative inflammatory response can be distinguished from the other breed-associated disorders based on histopathology and lesion topography, however the nature of the response primarily suggests a viral infection. In the present study PCR and RT-PCR technologies were employed on frozen cerebral tissue from confirmed cases of meningoencephalitis to target specific viruses and protozoa likely to be implicated and to exclude the presence of bacterial 16SrRNA. Secondly, degenerate primers were used to detect viruses of the herpesvirus and flavivirus families. In addition cerebral tissues were probed for West Nile Virus. Viral nucleic acid sequences to Borna disease virus, to louping ill, tick borne encephalitis, West Nile and other flaviviruses were not detected. Canine distemper virus was detected in one animal with 97% homology to strain A75/15. Degenerate PCR for herpesviruses detected viral amplification products in one animal with 90% homology to canine herpesvirus DNA polymerase gene. Protozoal amplification products were only detected in a single dog with pathological confirmation of a combination of lesions of greyhound meningoencephalitis and a protozoal encephalomyelitis. Neospora was confirmed with sequence homology to Austrian strain 1. Bacterial 16SrRNA was not detected. The present study supports previous observations that many of the known microbial causes of canine meningoencephalitis are not involved. Findings could reflect that the causal agent was not specifically targeted for detection, or that the agent is at undetectable levels or has been eliminated from brain tissue. The potential roles of genetics and of molecular mimicry also cannot be discounted.

Autoimmune channelopathies

Autoimmune disorders of the neuromuscular junction remain a paradigm for our understanding of autoimmunity. Since the role of autoantibodies to acetylcholine receptors in the pathogenesis of myasthenia gravis was first recognized in the 1970s, a range of antibody-mediated disorders of the neuromuscular junction have been described, each associated with an autoantibody to a specific ligand-gated receptor, voltage-gated ion channel or related protein. In addition, antibodies to a ganglionic form of acetylcholine receptor have been detected in autoimmune forms of autonomic neuropathy. In the past few years, a role for antibodies in disorders of the CNS has begun to emerge, challenging our previous concepts regarding the blood-brain barrier and the role of the humoral immune system in CNS pathology. Although it has not yet been definitively shown that these CNS conditions are antibody-mediated, the detection of the specific antibody supports a trial of immunosuppressive therapy to which many patients appear to respond. In this article, we review the roles of antibodies to receptors and ion channels in the peripheral and central nervous systems, concentrating on the recently defined autonomic and CNS conditions and on the role of antibody measurement in diagnosis and management.