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ABSTRACT: PURPOSE: Antibodies against neuronal surface proteins are increasingly recognized in autoimmune central nervous system (CNS) disorders in which seizures are the main or an important feature. The disorders include antibody-associated limbic encephalitis and N-methyl-D-aspartate receptor (NMDAR)encephalitis; however, seizures of autoimmune etiology may exist beyond the spectrum of these recognized syndromes. Because these seizures are potentially treatable with immune therapy, guidelines are needed to help in their early recognition. METHODS: We describe 13 representative children seen at our tertiary institution over a period of 3.5 years with suspected autoimmune epilepsy. Autoimmune epilepsy was suspected clinically when there was any of the following: (1) recognizable syndromes such as NMDAR encephalitis or limbic encephalitis, (2) evidence of CNS inflammation in cerebrospinal fluid or on magnetic resonance imaging (MRI), (3) the presence of other autoimmune diseases, or (4) positive response to immunotherapy. We tested these patients for neuronal surface antibodies (voltage gated potassium channel [VGKC]-complex, leucine rich glioma inactivated 1 [LGI1], contactin-associated protein-like 2 [CASPR2], and NMDAR) and glutamic acid decarboxylase (GAD) antibodies. We modified the J Neurol Neurosurg Psychiatry, 83, 2012, 638 guidelines that were designed to classify adults with neuronal surface antibody syndromes (NSAS), to be more appropriate for children with suspected autoimmune epilepsy. Using the modified guidelines, the 13 patients were classified into definite, probable, possible, unlikely, or unknown autoimmune epilepsy according to the presence of neuronal surface or GAD antibodies, and the response to immune therapy when given. KEY FINDINGS: Of the 13 patients, 11 were females, and the mean age was 6 years (range 1-13 years). Three patients had classical NMDAR encephalitis, two had VGKC encephalitis, two had limbic encephalitis with negative antibodies, three had epilepsy with other autoimmune diseases (one with high titer GAD antibodies), two had fever-induced refractory epileptic encephalopathy in school-aged children (FIRES), and one epileptic encephalopathy associated with VGKC antibodies. Seven patients of the 13 children with suspected autoimmune epilepsy were positive for neuronal surface antibodies (NMDAR, n = 3; VGKC-complex, n = 3; and GAD, n = 1). Immunotherapy was given to nine cases, and a positive response was more common in patients with positive neuronal surface antibodies (5/5) compared to those with negative antibodies (2/4). Applying the proposed guidelines, the classification of autoimmune epilepsy was definite in five, probable in one, possible in three, unlikely in two, and unknown in two patients. SIGNIFICANCE: Neuronal surface antibodies and GAD antibodies are present in a proportion of children with suspected autoimmune epilepsy and may define a treatable subgroup of childhood epilepsy. The proposed guidelines can be useful in the recognition of children with seizures of autoimmune etiology.
Epilepsia 03/2013; · 3.96 Impact Factor
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ABSTRACT: PURPOSE: Autoantibodies to specific neurologic proteins are associated with subacute onset encephalopathies, which often present with seizures that are poorly controlled by conventional antiepileptic drugs (AEDs). Previous cross-sectional studies have found specific neurologic antibodies in a small proportion of people with established epilepsy, but these investigations have seldom included patients with recent diagnosis. METHODS: We screened two large epilepsy cohorts to investigate the prevalence of multiple autoantibodies in adult patients with either established or newly diagnosed, untreated epilepsy. KEY FINDINGS: Eleven percent of patients had antibodies to one or more antigen: voltage-gated potassium channel (VGKC) complex proteins (5%), glycine receptors (3%), and glutamic acid decarboxylase (GAD) and N-methyl-d-aspartate (NMDA) receptors (1.7% each). There was no difference in the prevalence of antibodies, individually or collectively, between patients with established and newly diagnosed epilepsy or with generalized or focal epilepsy. There was, however, a significantly higher prevalence of positive antibody titers in patients with focal epilepsy of unknown cause than in those with structural/metabolic focal epilepsy (14.8% vs. 6.3%; p < 0.02). Newly diagnosed antibody-positive patients were less likely to achieve adequate seizure control with initial treatment than antibody-negative patients, but this difference failed to reach statistical significance. SIGNIFICANCE: The presence of autoantibodies is equally common in newly diagnosed and established epilepsy, it is therefore unlikely to be an epiphenomenon of long-standing refractory seizures.
Epilepsia 03/2013; · 3.96 Impact Factor
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Esther B E Becker,
Luigi Zuliani,
Rosemary Pettingill, Bethan Lang,
Patrick Waters,
Anna Dulneva,
Frank Sobott,
Mark Wardle,
Francesc Graus,
Luis Bataller,
Neil P Robertson,
Angela Vincent
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ABSTRACT: Relatively few studies have searched for potentially pathogenic antibodies in non-paraneoplastic patients with cerebellar ataxia.
We first screened sera from 52 idiopathic ataxia patients for binding of serum IgG antibodies to cerebellar neurons. One strong-binding serum was selected for immunoprecipitation and mass spectrometry, which resulted in the identification of contactin-associated protein 2 (CASPR2) as a major antigen. CASPR2 antibodies were then found by a cell-based assay in 9/88 (10%) ataxia patients, compared to 3/144 (2%) multiple sclerosis or dementia controls (p=0.011). CASPR2 is strongly expressed in the cerebellum, only partly in association with voltage-gated potassium channels.
Prospective studies are now needed to see whether identification of CASPR2 antibodies has relevance for the diagnosis and treatment of idiopathic cerebellar ataxia.
Journal of neurology, neurosurgery, and psychiatry 04/2012; 83(4):437-40. · 4.87 Impact Factor
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Sarosh R Irani,
Philippa Pettingill,
Kleopas A Kleopa,
Natasa Schiza,
Patrick Waters,
Claudio Mazia,
Luigi Zuliani,
Osamu Watanabe, Bethan Lang,
Camilla Buckley,
Angela Vincent
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ABSTRACT: A study was undertaken to describe the clinical spectrum, voltage-gated potassium channel (VGKC) complex antibody specificities, and central nervous system localization of antibody binding in 29 patients diagnosed with Morvan syndrome (MoS).
Clinical data were collected using questionnaires. Radioimmunoassay, cell-based assays, and mouse brain immunohistochemistry were used to characterize the serum antibodies.
Neuromyotonia (100%), neuropsychiatric features (insomnia 89.7%, confusion 65.5%, amnesia 55.6%, hallucinations 51.9%), dysautonomia (hyperhidrosis 86.2%, cardiovascular 48.3%), and neuropathic pain (62.1%) were the most common manifestations. A total of 93.1% of MoS patients were male. VGKC-complex antibodies were present in 23 of 29 (79%) MoS patients at referral; 24 of 27 available sera had CASPR2, LGI1, or both CASPR2 and LGI1 antibodies (3 also with contactin-2 antibodies). CASPR2 antibodies were generally higher titer than LGI1 antibodies. Tumors (41.4%), mainly thymomas, were associated with CASPR2 antibodies and a poor prognosis, whereas LGI1 antibodies were associated with serum hyponatremia. In brain tissue regions including the hypothalamus, raphe, and locus coeruleus, commercial antibodies to LGI1 bound to neuronal cell bodies including the antidiuretic hormone-secreting and orexin-secreting hypothalamic neurons, whereas CASPR2 commercial antibodies bound more often to the neuropil. MoS antibodies bound similarly, but there was evidence of additional antibodies in some sera that were not adsorbed by LGI1- or CASPR2-expressing cells and bound to mouse Caspr2(-/-) tissue.
MoS is clinically distinct from other VGKC-complex antibody-associated conditions, and usually is associated with high-titer CASPR2 antibodies, often accompanied by lower-titer LGI1 antibodies. CASPR2 and LGI1 antibodies bind to multiple brain regions, which helps to explain the multifocal clinical features of this disease, but other antibodies are likely to play a role in some patients and need to be characterized in future studies.
Annals of Neurology 03/2012; 72(2):241-55. · 11.09 Impact Factor
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ABSTRACT: Glycine receptor (GlyR) antibodies were recently identified in a few patients with progressive encephalomyelitis with rigidity and myoclonus (PERM); none of these patients had antibodies against glutamic acid decarboxylase (GAD). An inhibitory glycinergic transmission defect has also been implicated in the mechanism underlying saccadic oscillations, including ocular flutter or opsoclonus; GlyR antibodies have not been reported in these patients. The purpose was to determine whether GlyR antibodies are found in patients with PERM, ocular flutter syndrome (OFS), and opsoclonus-myoclonus syndrome (OMS). GlyR antibodies were first measured in archived sera and CSF from five patients, including one patient with GAD antibody-positive PERM, two patients with OFS, and two patients with OMS. GlyR antibodies were also measured in archived sera from nine other adult patients with OMS. GlyR antibodies and GAD antibodies were both found at high titers in the serum and CSF of the patient with PERM, and their levels paralleled disease activity over time. GlyR antibodies were not found at significant levels in 13 patients with saccadic oscillations. GlyR and GAD antibodies can co-exist in PERM and follow the clinical course. Although saccadic oscillations are a feature of this condition, GlyR antibodies are not commonly found in patients with isolated saccadic oscillations.
Journal of Neurology 01/2012; 259(8):1566-73. · 3.47 Impact Factor
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ABSTRACT: An elderly woman presented with disorganised thinking, unusual behaviour and clustered episodes of speech arrest accompanied by right-sided face and arm twitching. The following investigations were normal: interictal electroencephalography, brain MRI, cerebrospinal fluid viral PCR and cell count and voltage-gated potassium channel-complex, N-methyl-d-aspartate receptor, gamma-aminobutyric acid (B) receptor, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor, glycine receptor, glutamic acid decarboxylase and paraneoplastic antibodies. The syndrome showed partial spontaneous resolution but 1 year later, typical postencephalopathic features persisted including disinhibition and alteration of sleep-wake cycle. The most likely clinical diagnosis was autoimmune encephalitis and the broader differential diagnoses are discussed within the article. This case demonstrates the need to be aware of this under-recognised and potentially treatable entity.
Case Reports 01/2012; 2012.
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ABSTRACT: Lambert-Eaton myasthenic syndrome (LEMS) is a neuromuscular autoimmune disease that has served as a model for autoimmunity and tumour immunology. In LEMS, the characteristic muscle weakness is thought to be caused by pathogenic autoantibodies directed against voltage-gated calcium channels (VGCC) present on the presynaptic nerve terminal. Half of patients with LEMS have an associated tumour, small-cell lung carcinoma (SCLC), which also expresses functional VGCC. Knowledge of this association led to the discovery of a wide range of paraneoplastic and non-tumour-related neurological disorders of the peripheral and central nervous systems. Detailed clinical studies have improved our diagnostic skills and knowledge of the pathophysiological mechanisms and association of LEMS with SCLC, and have helped with the development of a protocol for early tumour detection.
The Lancet Neurology 12/2011; 10(12):1098-107. · 23.46 Impact Factor
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ABSTRACT: Autoimmune autonomic ganglionopathy (AAG) is a rare disorder that presents with pandysautonomia typically in middle age and elderly patients. AAG is typically associated with serum autoantibodies that bind to the alpha-3 subunit of the ganglionic acetylcholine receptor (α3-AChR Ab). We report a 13 year old girl who presented with gut pseudo-obstruction, bladder dysfunction and dilated pupils unresponsive to pilocarpine. She had positive α3-AChR Ab plus other autoantibodies suggesting an autoimmune diathesis. Our patient was initially resistant to steroid therapy but responded to the addition of azathioprine resulting in a near complete clinical remission. We conclude that pandysautonomia associated with α3-AChR Ab can occur in children and has multi-organ involvement.
European journal of paediatric neurology: EJPN: official journal of the European Paediatric Neurology Society 11/2011; 16(4):396-8. · 2.01 Impact Factor
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ABSTRACT: Autoantibodies to surface proteins that influence neuronal excitability are increasingly found in different forms of epilepsy or encephalitis in adults, and are also beginning to be identified in children. The conditions are often refractory to traditional antiepileptic drugs. Detection of these antibodies can help to identify forms of epilepsy that may respond to immunotherapies.
Epilepsia 10/2011; 52 Suppl 8:8-11. · 3.96 Impact Factor
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ABSTRACT: Autoantibodies that bind to voltage-gated potassium-channel complex proteins (VGKC-complex antibodies) occur frequently in adults with limbic encephalitis presenting with cognitive impairment and seizures. Recently, VGKC-complex antibodies have been described in a few children with limbic encephalitis, and children with unexplained encephalitis presenting with status epilepticus. We report a case of infantile-onset epileptic spasms and developmental delay compatible with epileptic encephalopathy. Our patient was a female infant, aged 4 months at presentation. She had evidence of immune activation in the central nervous system with elevated cerebrospinal fluid neopterin and mirrored oligoclonal bands, which prompted testing for autoantibodies. VGKC-complex antibodies were elevated (201 pmol/L, normal<100), but extended antibody testing, including leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein 2 (CASPR2), was negative. The patient showed a partial response to steroid treatment, which was started late in the disease course. On review at 13 months of age, her development was consistent with an age of 5 to 6 months. These results suggest that VGKC-complex antibodies might represent a marker of immune therapy responsiveness in a subgroup of patients with infantile epileptic encephalopathy.
Developmental Medicine & Child Neurology 08/2011; 53(11):1058-60. · 2.92 Impact Factor
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ABSTRACT: To review the recent literature describing the detection and clinical importance of serum antibodies in patients with various epilepsies and other seizure-related disorders.
Auto-antibodies to the NMDA, GABAB and AMPA receptors and to LGI1, CASPR2 and Contactin-2, components of the voltage-gated potassium channel complex, have been detected in the serum of patients with seizures. These antigenic targets are ion channels, receptors and accessory proteins important in both cellular homeostasis and governing the electrical activity of the brain. Antibodies to glutamic acid decarboxylase (GAD) have been found in patients with temporal lobe epilepsy. Antibodies to LGI1 have been described in around 90% of patients with the newly described epileptic syndrome of faciobrachial dystonic seizures.
An increasing number of antibodies have been described in the epilepsies and other seizure-related disorders. Evidence of direct pathogenicity comes from the extracellular domain targeted by all of these antibodies (other than GAD) and the often dramatic clinical and serological response to immunotherapies, when antiepileptic drugs may be ineffective. Definitive proof as to the pathological relevance of these antibodies will be achieved in the generation of an animal model that demonstrates the clinical phenotype of these antibody-mediated disorders.
Current opinion in neurology 02/2011; 24(2):146-53. · 5.43 Impact Factor
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Maarten J Titulaer,
Paul Maddison,
Jacob K Sont,
Paul W Wirtz,
David Hilton-Jones,
Rinse Klooster,
Nick Willcox,
Marko Potman,
Peter A E Sillevis Smitt,
Jan B M Kuks,
Bart O Roep,
Angela Vincent,
Silvère M van der Maarel,
J Gert van Dijk, Bethan Lang,
Jan J G M Verschuuren
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ABSTRACT: Approximately one half of patients with Lambert-Eaton myasthenic syndrome (LEMS) have small-cell lung carcinomas (SCLC), aggressive tumors with poor prognosis. In view of its profound impact on therapy and survival, we developed and validated a score to identify the presence of SCLC early in the course of LEMS.
We derived a prediction score for SCLC in LEMS in a nationwide cohort of 107 Dutch patients, and validated it in a similar cohort of 112 British patients. A Dutch-English LEMS Tumor Association Prediction (DELTA-P) score was developed based on multivariate logistic regression.
Age at onset, smoking behavior, weight loss, Karnofsky performance status, bulbar involvement, male sexual impotence, and the presence of Sry-like high-mobility group box protein 1 serum antibodies were independent predictors for SCLC in LEMS. A DELTA-P score was derived allocating 1 point for the presence of each of the following items at or within 3 months from onset: age at onset ≥ 50 years, smoking at diagnosis, weight loss ≥ 5%, bulbar involvement, erectile dysfunction, and Karnofsky performance status lower than 70. The area under the curve of the receiver operating curve was 94.4% in the derivation cohort and 94.6% in the validation set. A DELTA-P score of 0 or 1 corresponded to a 0% to 2.6% chance of SCLC, whereas scores of 4, 5, and 6 corresponded to chances of SCLC of 93.5%, 96.6%, and 100%, respectively.
The simple clinical DELTA-P score discriminated patients with LEMS with and without SCLC with high accuracy early in the course of LEMS.
Journal of Clinical Oncology 01/2011; 29(7):902-8. · 18.37 Impact Factor
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Journal of Neurology 10/2010; 258(4):686-8. · 3.47 Impact Factor
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Sarosh R Irani,
Andrew W Michell, Bethan Lang,
Philippa Pettingill,
Patrick Waters,
Michael R Johnson,
Jonathan M Schott,
Richard J E Armstrong,
Alessandro S Zagami,
Andrew Bleasel,
Ernest R Somerville,
Shelagh M J Smith,
Angela Vincent
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ABSTRACT: To describe a distinctive seizure semiology that closely associates with voltage-gated potassium channel (VGKC)-complex/Lgi1 antibodies and commonly precedes the onset of limbic encephalitis (LE).
Twenty-nine patients were identified by the authors (n = 15) or referring clinicians (n = 14). The temporal progression of clinical features and serum sodium, brain magnetic resonance imaging (MRI), positron emission tomography/single photon emission computed tomography, and VGKC-complex antibodies was studied.
Videos and still images showed a distinctive adult-onset, frequent, brief dystonic seizure semiology that predominantly affected the arm and ipsilateral face. We have termed these faciobrachial dystonic seizures (FBDS). All patients tested during their illness had antibodies to VGKC complexes; the specific antigenic target was Lgi1 in 89%. Whereas 3 patients never developed LE, 20 of the remaining 26 (77%) experienced FBDS prior to the development of the amnesia and confusion that characterize LE. During the prodrome of FBDS alone, patients had normal sodium and brain MRIs, but electroencephalography demonstrated ictal epileptiform activity in 7 patients (24%). Following development of LE, the patients often developed other seizure semiologies, including typical mesial temporal lobe seizures. At this stage, investigations commonly showed hyponatremia and MRI hippocampal high T2 signal; functional brain imaging showed evidence of basal ganglia involvement in 5/8. Antiepileptic drugs (AEDs) were generally ineffective and in 41% were associated with cutaneous reactions that were often severe. By contrast, immunotherapies produced a clear, and often dramatic, reduction in FBDS frequency.
Recognition of FBDS should prompt testing for VGKC-complex/Lgi1 antibodies. AEDs often produce adverse effects; treatment with immunotherapies may prevent the development of LE with its potential for cerebral atrophy and cognitive impairment.
Annals of Neurology 10/2010; 69(5):892-900. · 11.09 Impact Factor
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ABSTRACT: Antibodies to glutamic acid decarboxylase (GAD), the major pathway for the synthesis of c-aminobutyric acid(GABA) in humans, are found at elevated levels in a subgroup of patients with chronic epilepsy. To test whether the antibodies were associated with changes in cortical GABA levels we used magnetic resonance spectroscopy. Four patients with epilepsy and high serum GAD antibody levels (107-6,200 units/ml) and 10 healthy controls were recruited. A 3T GABA-optimized spectrum was obtained from a reproducible voxel in the cortex. Compared to the control group, the patient group had significantly lower GABA concentrations within the cortex. Demonstration of an association between high serum GAD antibodies and low cortical GABA levels in patients with epilepsy suggests that GAD antibodies are, at least, a marker of a specific disease process and support a role for immune-mediated GABAergic dysfunction.
Epilepsia 09/2010; 51(9):1898-901. · 3.96 Impact Factor
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ABSTRACT: Antibodies that immunoprecipitate (125)I-alpha-dendrotoxin-labelled voltage-gated potassium channels extracted from mammalian brain tissue have been identified in patients with neuromyotonia, Morvan's syndrome, limbic encephalitis and a few cases of adult-onset epilepsy. These conditions often improve following immunomodulatory therapies. However, the proportions of the different syndromes, the numbers with associated tumours and the relationships with potassium channel subunit antibody specificities have been unclear. We documented the clinical phenotype and tumour associations in 96 potassium channel antibody positive patients (titres >400 pM). Five had thymomas and one had an endometrial adenocarcinoma. To define the antibody specificities, we looked for binding of serum antibodies and their effects on potassium channel currents using human embryonic kidney cells expressing the potassium channel subunits. Surprisingly, only three of the patients had antibodies directed against the potassium channel subunits. By contrast, we found antibodies to three proteins that are complexed with (125)I-alpha-dendrotoxin-labelled potassium channels in brain extracts: (i) contactin-associated protein-2 that is localized at the juxtaparanodes in myelinated axons; (ii) leucine-rich, glioma inactivated 1 protein that is most strongly expressed in the hippocampus; and (iii) Tag-1/contactin-2 that associates with contactin-associated protein-2. Antibodies to Kv1 subunits were found in three sera, to contactin-associated protein-2 in 19 sera, to leucine-rich, glioma inactivated 1 protein in 55 sera and to contactin-2 in five sera, four of which were also positive for the other antibodies. The remaining 18 sera were negative for potassium channel subunits and associated proteins by the methods employed. Of the 19 patients with contactin-associated protein-antibody-2, 10 had neuromyotonia or Morvan's syndrome, compared with only 3 of the 55 leucine-rich, glioma inactivated 1 protein-antibody positive patients (P < 0.0001), who predominantly had limbic encephalitis. The responses to immunomodulatory therapies, defined by changes in modified Rankin scores, were good except in the patients with tumours, who all had contactin-associated-2 protein antibodies. This study confirms that the majority of patients with high potassium channel antibodies have limbic encephalitis without tumours. The identification of leucine-rich, glioma inactivated 1 protein and contactin-associated protein-2 as the major targets of potassium channel antibodies, and their associations with different clinical features, begins to explain the diversity of these syndromes; furthermore, detection of contactin-associated protein-2 antibodies should help identify the risk of an underlying tumour and a poor prognosis in future patients.
Brain 09/2010; 133(9):2734-48. · 9.46 Impact Factor
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Sarosh R Irani,
Katarzyna Bera,
Patrick Waters,
Luigi Zuliani,
Susan Maxwell,
Michael S Zandi,
Manuel A Friese,
Ian Galea,
Dimitri M Kullmann,
David Beeson, Bethan Lang,
Christian G Bien,
Angela Vincent
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ABSTRACT: Antibodies to the N-methyl-d-aspartate subtype of glutamate receptor have been associated with a newly-described encephalopathy that has been mainly identified in young females with ovarian tumours. However, the full clinical spectrum and treatment responses are not yet clear. We established a sensitive cell-based assay for detection of N-methyl-d-aspartate receptor antibodies in serum or cerebrospinal fluid, and a quantitative fluorescent immunoprecipitation assay for serial studies. Although there was marked intrathecal synthesis of N-methyl-d-aspartate receptor antibodies, the absolute levels of N-methyl-d-aspartate receptor antibodies were higher in serum than in cerebrospinal fluid. N-methyl-d-aspartate receptor antibodies were of the immunoglobulin G1 subclass and were able to activate complement on N-methyl d-aspartate receptor-expressing human embryonic kidney cells. From questionnaires returned on 44 N-methyl-d-aspartate receptor antibody-positive patients, we identified a high proportion without a detected tumour (35/44, 80%: follow-up 3.6-121 months, median 16 months). Among the latter were 15 adult females (43%), 10 adult males (29%) and 10 children (29%), with four in the first decade of life. Overall, there was a high proportion (29%) of non-Caucasians. Good clinical outcomes, as defined by reductions in modified Rankin scores, correlated with decreased N-methyl-d-aspartate receptor antibody levels and were associated with early (<40 days) administration of immunotherapies in non-paraneoplastic patients (P < 0.0001) and earlier tumour removal in paraneoplastic patients (P = 0.02). Ten patients (23%) who were first diagnosed during relapses had no evidence of tumours but had received minimal or no immunotherapy during earlier episodes. Temporal analysis of the onset of the neurological features suggested progression through two main stages. The time of onset of the early features, characterized by neuropsychiatric symptoms and seizures preceded by a median of 10-20 days, the onset of movement disorders, reduction in consciousness and dysautonomia. This temporal dichotomy was also seen in the timing of cerebrospinal fluid, electroencephalographic and in the rather infrequent cerebral imaging changes. Overall, our data support a model in which the early features are associated with cerebrospinal fluid lymphocytosis, and the later features with appearance of oligoclonal bands. The immunological events and neuronal mechanisms underlying these observations need to be explored further, but one possibility is that the early stage represents diffusion of serum antibodies into the cortical grey matter, whereas the later stage results from secondary expansion of the immunological repertoire within the intrathecal compartment acting on subcortical neurons. Four patients, who only had temporal lobe epilepsy without oligoclonal bands, may represent restriction to the first stage.
Brain 06/2010; 133(Pt 6):1655-67. · 9.46 Impact Factor
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ABSTRACT: The concept of epilepsy and seizure disorders caused by autoantibodies to specific neuronal membrane proteins has developed significantly during the past few years.
Antibodies to cell-surface membrane proteins such as voltage-gated potassium channels or N-methyl-D-aspartate receptors, or to glutamic acid decarboxylase, are found in patients with different forms of limbic encephalitis, and in a few patients with epilepsy as their main or only condition. Many of these patients do not show a good response to conventional antiepileptic drugs, but respond to immunotherapies. By contrast, studies of other antibodies in idiopathic forms of epilepsy, or epilepsy associated with systemic lupus erythematosus or coeliac disease, have not in general disclosed consistent, clinically helpful results.
There are a growing number of specific antibodies associated with new onset epilepsy. These patients are likely to have an immune-mediated disorder that may benefit from immunotherapies. In autoimmune diseases such as systemic lupus erythematosus or coeliac disease, antibodies to specific membrane targets may also prove to be important in the future.
Current opinion in neurology 02/2010; 23(2):144-50. · 5.43 Impact Factor
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ABSTRACT: Encephalitis lethargica (EL) describes an encephalitis with psychiatric, sleep, and extrapyramidal movement disorders. Dyskinetic and parkinsonian forms have been described. EL shares clinical features with the anti-N-methyl-D-aspartate receptor (NMDAR-Ab) encephalitis. We studied 20 sera from pediatric patients with contemporary EL. Ten sera (from 2 males and 8 females, aged 1.3-13 years) and 6/6 cerebrospinal fluid samples were positive for NMDAR-Ab. NMDAR-Ab-positive patients had dyskinesias, agitation, seizures, and insomnia, whereas parkinsonism and somnolence dominated in the NMDAR-Ab-negative children. We were unable to identify any tumors. The dyskinetic form of EL is an NMDAR-Ab encephalitis and can affect very young children.
Annals of Neurology 11/2009; 66(5):704-9. · 11.09 Impact Factor
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ABSTRACT: The Lambert Eaton myasthenic syndrome (LEMS) is a paraneoplastic disorder associated with raised serum voltage-gated calcium channel (VGCC) antibodies in patients with small cell lung cancer (SCLC). VGCC can also be found in patients with SCLC and cerebellar ataxia. This was a prospective study to assess the incidence of clinical and subclinical LEMS or other neurologic disease in patients with SCLC.
Sixty-three unselected patients with cytologically or histologically confirmed SCLC consented to participate. Pretreatment assessment included a neurologic symptom questionnaire, examination for physical signs of LEMS or ataxia, measurement of serum titers of antibodies to P/Q-type VGCCs by radioimmunoassay in all patients and electrophysiological examination where appropriate.
Neurologic symptoms unrelated to LEMS occurred in 26% of patients. Five patients (8%) had raised serum VGCC antibodies (range, 69-1553 pM/l) diagnostic of LEMS, two (3%) of whom had LEMS on clinical and electrophysiological grounds. Both also had mild cerebellar ataxia. There was no association between serum VGCC antibody titer and survival.
Routine measurement of VGCC antibodies in patients without clinical LEMS is unlikely to assist either in management of SCLC or in assessment of prognosis.
Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 11/2009; 5(1):34-8. · 4.55 Impact Factor
