Long-term course of Dravet syndrome: a study from an epilepsy center in Japan.

OBJECTIVE: This study attempted to clarify the long-term course of Dravet syndrome (DS). METHODS: Sixty-four patients diagnosed with DS (44 with typical DS, and 20 with atypical DS) were studied. The long-term outcomes of clinical seizures, electroencephalographic findings, neuropsychological findings, and social situation were analyzed. The follow-up period ranged from 11 to 34 years 5 months (median 24 years). RESULTS: At the last visit, the ages ranged from 19 years to 45 years (median 30 years). Fifty-nine patients continued to have generalized tonic-clonic seizures (GTCS). Status epilepticus and unilateral seizures were not observed and myoclonic seizures, atypical absence seizures, and photosensitive seizures were resolved in most patients. The frequency of complex partial seizures was equally low, with five patients at presentation and six patients at the last visit, respectively. Five patients achieved seizure remission (seizure-free for 1 year or longer). Only 1 of 44 patients with typical DS had seizure remission, whereas 4 of 20 patients with atypical DS remitted, with a statistically significant difference between the two phenotypes (p = 0.03). Intellectual disability was found in all patients; especially, severe intellectual disability was prevalent. Patients with atypical DS tended to have milder intellectual disability compared to those with typical DS (p = 0.0283). Occipital alpha rhythm in the basic activity was associated with milder intellectual disability (p = 0.0085). The freedom from seizures correlated with appearance of occipital alpha rhythms (p = 0.0008) and disappearance of epileptic discharges (p = 0.0004). Two patients with GTCS died. Mutations of the neuronal voltage-gated sodium channel alpha subunit type 1 gene were detected at a high frequency (33 of 36 patients examined). Seizure remission was found only in the missense mutation group. SIGNIFICANCE: The long-term seizure and intellectual outcomes are extremely poor in patients with typical DS compared to those with atypical DS. Epilepsy phenotype may influence long-term course of DS.

Immunomodulatory therapy versus surgery for Rasmussen syndrome in early childhood.

We examined seizure, cognitive, and motor outcomes in patients with Rasmussen syndrome or Rasmussen encephalitis (RS), after recent initiation of immunomodulatory therapies. Among 53 patients with a diagnosis of RS referred from all over Japan, 49 patients (male 22, female 27) with symptoms and findings characteristic of RS were evaluated. Regular intravenous immunoglobulin (IVIg) therapy was administered at a dose of 100mg/kg/day, etc. Regular steroid pulse therapy was conducted with methylprednisolone at a dose of 30mg/kg/day (children) or 1000mg/day (adults) for 3days. Tacrolimus was given at an initial dose of 0.1mg/kg/day (children). Mean onset age was 8.7±10.5years. Seizure-free rate was 71% after treatment by functional hemispherectomy (FH), and response rate for seizures was 81% by regular steroid pulse therapy, 42% by tacrolimus therapy, and 23% by regular IVIg therapy. Rate of patients with IQ higher than 80 (R80) was 50% by regular steroid pulse therapy, 43% by regular IVIg therapy, 29% by tacrolimus therapy, and 0% by FH. R80 after regular steroid pulse therapy was 100% in patients without MRI lesions, and 37% in those with advanced MRI lesions. Improvement of motor function (paresis) was observed only by immunomodulatory therapy. Motor function was aggravated in 100% of patients treated by FH, 62% by regular IVIg, and 10% by regular steroid pulse therapy. We suggest a new treatment strategy for RS using early immunomodulatory therapy: initiation of regular steroid pulse therapy after early diagnosis indicated by biomarkers, then switching to tacrolimus therapy after several months.

Temporal changes in brain MRI findings in Rasmussen syndrome.

INTRODUCTION: MRI data is essential for early diagnosis and evaluation of surgical indication in patients with Rasmussen syndrome (RS). In the present study, we examined the status and evolutionary changes in MRI lesions to identify the MRI characteristics of RS. METHODS: MRI of 15 RS patients was examined regarding frequency and distribution of atrophic lesions on T1-weighted images and high intensity lesions on FLAIR or T2-weighted images. RESULTS: In 13 patients, atrophic lesions were observed predominantly in the frontal lobes with various extent of involvement. High intensity lesions were also observed in 13 patients. High intensity lesions were significantly more prevalent in the cortex of patients with later onset and were present in the insula in 37.5% of epilepsia partialis continua (EPC) type patients and in 57.1% of non-EPC type. Early MRI showed various combinations of atrophic lesions or high intensity lesions in seven of nine patients who underwent MRI examinations within one year of their first seizure. Serial MRI revealed high intensity lesions with characteristic features of regression (20.0% of patients), fluctuation (regression followed by reappearance; 33.3%) and expansion (46.7%). Appearance and reappearance of high intensity lesions in the cortex and/or subcortical white matter were associated with aggravation of seizures. Bilateral high intensity lesions were observed in three patients with unilateral epileptogenic foci, who were successfully treated by surgical intervention. CONCLUSION: Dynamic evolutionary changes in lesions (regression, fluctuation and expansion of high intensity lesions), as observed on MRI, may be a diagnostic feature of Rasmussen syndrome.

Lamotrigine is favourable for startle-induced seizures.

Falling due to startle-induced seizures (SISs) often leads to injury. The triggers of SIS are mostly unexpected auditory stimuli, which are too common to avoid in daily life. As SISs are often refractory to conventional medications, effective therapeutic options have to be established. We report a small series of six patients treated with lamotrigine (LTG) as add-on therapy. Seizure control was improved greatly in three of the six patients, resulting in less restricted daily life, but no effect was observed in two and a skin rash developed in one. Patient 1 was a 19-year-old man. His seizure comprised of a sudden tonic extension of the extremities induced by auditory or visual stimulus. He fell down due to SISs, five to ten times a day, with frequent injuries. After adding LTG to treatment with valproate (VPA) and clobazam (CLB), SISs were reduced to once a month. Patient 2 was a 51-year-old woman. Sudden tonic extension of all limbs induced by unexpected sounds frequently threw her down onto the floor. Addition of LTG to treatment with CLB, zonisamide and phenytoin reduced her SISs from several to less than once a day. Patient 3 was a seven-year-old girl with post-encephalitic epilepsy. After adjunctive treatment of LTG to VPA, the severity of SISs became milder thus avoiding injury, although seizure frequency did not decrease. LTG is potentially effective for the treatment of SISs and may prevent falling. The addition of LTG treatment dramatically improved the lives of the patients presented here and should be considered as an option for startle-induced seizures.

[Remarkable effect of a modified ketogenic diet in a boy with focal seizures followed by epileptic spasms in a cluster].

A modified ketogenic diet was demonstrated to be remarkably effective in a child with intractable symptomatic focal epilepsy with combined seizures of focal seizures and epileptic spasms (ES) in a cluster (ESC). ES started at 8 months of age and disappeared with ACTH therapy. At the age of 13 months, the child began to have intractable focal seizures that, later, were followed by ESC 10 times a day. Brain MRI showed only a non-specific diffuse cerebral atrophy. Interictal EEG showed high amplitude diffuse disorganized slow waves with prominent sharp waves predominant over the bilateral occipital region. We started a modified ketogenic diet (mKD) treatment without fasting or a water/calorie limitation. Since the 20th day of mKD, the patient has been seizure free (6 months) without adverse effects. EEG showed remarkable improvement and he has some improvement in the developmental milestones. A modified ketogenic diet is easier to start and continue compared to the classic ketogenic diet, and should be tried in intractable epilepsies that are not treatable surgically early in life from the developmental prognosis point of view.

Retrospective multiinstitutional study of the prevalence of early death in Dravet syndrome.

PURPOSE: A questionnaire survey was conducted in Japan to investigate the causes and prevalence of death related to Dravet syndrome. METHODS: A questionnaire was delivered to 246 hospitals at which physicians were treating childhood epilepsy to gain information about the total number of patients with Dravet syndrome and their prevalence of early death. KEY FINDINGS: Responses to the survey were collected from 91 hospitals, and a total of 63 of 623 patients with Dravet syndrome died. Data from 59 of these patients were analyzed. The patients' ages at death ranged from 13 months to 24 years and 11 months, with a median age of 6 years and 8 months. The analysis showed that the risk of mortality remained high up to approximately 12 years of age. The causes of mortality included sudden death in 31 patients (53%), acute encephalopathy with status epilepticus (SE) in 21 patients (36%), drowning in 6 patients (10%), and acute hepatopathy in one patient (1%). The incidence of sudden death reached a first peak at 1-3 years of age and reached a second peak at 18 years and older. In contrast, the incidence of acute encephalopathy with SE reached a sharp peak at 6 years of age. Seven of 10 patients who underwent an SCN1A mutation analysis exhibited positive mutations without a specific mutation site. SIGNIFICANCE: In the present study, the prevalence of Dravet syndrome-related mortality was 10.1%. The incidence of sudden death and acute encephalopathy with SE was the highest in infancy (1-3 years) and at early school ages (with a peak at 6 years), respectively. After approximately 12 years of age, the risk of mortality declined sharply. Neither the treatment nor the number of seizures was associated with any cause of mortality. In addition, it is difficult to predict which factors lead to a fatal outcome.

Mortality in Dravet syndrome: search for risk factors in Japanese patients.

A questionnaire survey was conducted in Japan to investigate the causes and prevalence of death related to Dravet syndrome. The questionnaire was delivered to 246 hospitals at which physicians were treating childhood epilepsy to gain information about the total number of patients with Dravet syndrome and the prevalence of early death due to the disorder. Responses to the survey were collected from 91 hospitals, and a total of 63 of 623 patients with Dravet syndrome had died. Data from 59 of these patients were analyzed. The age at death for these patients ranged from 13 months to 24 years and 11 months, with a median age of 6 years and 8 months. The causes of mortality included sudden death in 31 patients (53%), acute encephalopathy with status epilepticus (SE) in 21 patients (36%), drowning in 6 patients (10%), and other causes in one patient (1%). The incidence of sudden death reached a first peak at 1-3 years of age and a second peak at 18 years and older. In contrast, the incidence of acute encephalopathy with SE reached a peak at 6 years of age. Seven of the 10 patients who underwent SCN1A mutation analysis exhibited positive mutations but exhibited no consistent phenotype. The prevalence of Dravet syndrome-related mortality was 10.1%. The incidence of sudden death and acute encephalopathy with SE was higher in infancy (1-3 years) and at early school ages (with a peak at 6 years), respectively. Neither the treatment nor the number of seizures was associated with any cause of mortality. Factors leading to a fatal outcome are difficult to predict.

[Symptoms and clinical course of epilepsy with myoclonic absences].

There is no comprehensive study so far in Japan on epilepsy with myoclonic absences (EMA), characterized by myoclonic absences (MA) as a specific seizure type. We retrospectively studied 9 patients (4 males and 5 females) with EMA confirmed by ictal video EEG and polygraph (EEG+EMG) recordings. The age at MA onset ranged from 18 to 92 months and the age at the last follow-up ranged from 3 to 39 years. The patients had IQ of 40 to 79. Eight patients had been free from seizures for more than one year at the last follow up. MA was controlled by valproate sodium monotherapy or combination of valproate sodium and ethosuximide with appropriate plasma levels. Generalized tonic clonic seizures and severe mental retardation were not necessarily associated with poor seizure outcome. Patients with long MA duration or MA status epilepticus were prone to be refractory to medication. EMA can be divided into two subgroups based on the seizure outcome, favorable and unfavorable. Further large-scale study is required.

KCC2 was downregulated in small neurons localized in epileptogenic human focal cortical dysplasia.

Focal cortical dysplasia (FCD), which is characterized histologically by disorganized cortical lamination and large abnormal cells, is one of the major causes of intractable epilepsies. γ-aminobutyric acid (GABA)(A) receptor-mediated synchronous depolarizing potentials have been observed in FCD tissue. Since alterations in Cl(-) homeostasis might underlie these depolarizing actions of GABA, cation-Cl(-) cotransporters could play critical roles in the generation of these abnormal actions. We examined the expression patterns of NKCC1 and KCC2 by in situ hybridization histochemistry and immunohistochemistry in FCD tissue obtained by surgery from patients with intractable epilepsy. KCC2 mRNA and protein were expressed not only in non-dysplastic neurons in histologically normal portions located in the periphery of the excised cortex, but also in dysplastic cells in FCD tissue. The levels of KCC2 mRNA and protein were significantly decreased in the neurons around large abnormal neurons (giant neurons), but not in giant neurons, compared with non-dysplastic neurons. The neurons localized only around giant neurons significantly smaller than non-dysplastic neurons. However NKCC1 expression did not differ among these cell types. These results suggest that the intracellular Cl(-) concentration ([Cl(-)](i)) of small neurons might increase, so that depolarizing GABA actions could occur in the FCD tissue of epileptic foci.

[Effectiveness of topiramate in eleven patients with Dravet syndrome].

Dravet syndrome is a rare, but highly refractory epilepsy syndrome. As conventional drugs are not effective, introduction of new effective drugs in clinical use will benefit patients with this disease. We assessed the effectiveness of topiramate (TPM) as adjunctive therapy in 11 patients with Dravet syndrome. TPM was started at doses ranging from 10 to 50 mg/day (0.57 to 2.0 mg/kg/day), and the dosage was increased gradually up to the maximum dose (9 mg/kg/day) depending on efficacy and tolerability. The frequencies of convulsive seizures (generalized tonic-clonic seizures, unilateral seizures, partial onset generalized tonic-clonic seizures) during two months before starting TPM, two months after starting TPM, and the fifth and sixth months after starting TPM were determined. The mean dose (mean +/- SD) of TPM at the second month was 2.7 +/- 1.5 mg/kg/day (1.0-5.7 mg/kg/day, n= 11), and that at the sixth month was 4.5 +/- 2.2 mg/kg/day (1.0-7.3 mg/kg/day, n=10). Evaluation at the second month revealed that one of 11 patients (9%) became seizure-free, six patients (54%) showed greater than 50% seizure reduction, three patients (27%) showed less than 50% seizure reduction, and one patient (9%) had aggravation of convulsive seizures resulting in discontinuation of TPM at the first month. Evaluation at the sixth month revealed that one of 10 patients (10%) was seizure-free, seven patients (70%) had greater than 50% seizure reduction, two patients (20%) had less than 50% seizure reduction, and no patient (0%) had aggravation. Adverse effects were observed in five patients; dizziness in three patients, sleepiness in three patients, and oligohidrosis in one patient. In the present study, TPM was useful as an adjunctive therapy to reduce the frequency of convulsive seizures in patients with Dravet syndrome. A large-scale efficacy study of TPM for Dravet syndrome is warranted.

Deletions of SCN1A 5' genomic region with promoter activity in Dravet syndrome.

Mutations involving the voltage-gated sodium channel alpha(I) gene SCN1A are major genetic causes of childhood epileptic disorders, as typified by Dravet syndrome. Here we investigated the upstream regions of the SCN1A 5' noncoding exons and found two major regions with promoter activity. These two major promoters were simultaneously active in various brain regions and in most neurons. Using multiplex ligation-dependent probe amplification (MLPA) assays with probes for the 5' noncoding exons, their upstream regions, and all coding exons of SCN1A, we investigated 130 epileptic patients who did not show any SCN1A mutations by sequence analysis of all coding exons and exon-intron boundaries. Among 71 Dravet syndrome patients, we found two patients with heterozygous microdeletions removing the 5' noncoding exons and regions with promoter activity but not affecting the coding exons. We also identified four patients with deletions/duplication in the coding region. One patient with symptomatic focal epilepsy also showed a deletion in the coding region. This study provides the first case of microdeletion limited to the SCN1A 5' promoter region with the coding sequence preserved, and indicates the critical involvement of this upstream region in the molecular pathology of Dravet syndrome.

HLA class I markers in Japanese patients with carbamazepine-induced cutaneous adverse reactions.

Carbamazepine (CBZ) is frequently used for treating epilepsy, but this drug causes cutaneous adverse drug reactions (cADRs) that may range from mild to severe. It is reported recently that the human leukocyte antigen HLA-B*1502 is associated with Stevens-Johnson syndrome (SJS) induced by CBZ in Han Chinese. We examined HLA class I in 15 Japanese patients who fulfilled the diagnostic criteria for CBZ-induced cADRs (mild in 10 and severe = SJS in 5). HLA-B*1518, HLA-B*5901 and HLA-C*0704 alleles showed higher relative risks (above 10.0) for severe cADRs. The haplotype (HLA-A*2402-B*5901-C*0102) had high relative risk (16.09) for severe cADRs. In patients with severe cADRs, frequencies of HLA-A*1101, HLA-A*3303, HLA-B*1501, HLA-B*4403, HLA-B*5101, HLA-B*5201, HLA-C*0702, and HLA-C*1202 alleles are relatively lower than in the Japanese population. These data may suggest that HLA-B*5901 is one of the candidate markers for CBZ-induced SJS in Japanese.

Neural connection between bilateral basal temporal regions: cortico-cortical evoked potential analysis in patients with temporal lobe epilepsy.

OBJECTIVE: In patients with temporal lobe epilepsy, invasive electroencephalographic study has shown that epileptic activities arising from the unilateral temporal lobe often propagate to the contralateral temporal lobe. Which commissural pathways are responsible for this spreading remains controversial. Some previous studies, however, have suggested that interhemispheric connections between bilateral basal temporal regions (BTR) might have a significant role in propagation of epileptic activities. METHODS: We attempted to elucidate the neural connections between bilateral BTRs using the cortico-cortical evoked potential (CCEP) method. Five consecutive patients with temporal lobe epilepsy who underwent intracranial electroencephalographic monitoring were studied. RESULTS: CCEP responses were recorded from a total of 24 electrodes after stimulation of the contralateral BTRs (24 CCEPs/720 recordings; 3.33%). There were 3 types of CCEP waveform: type N-P (16 of 24; 66.7%) consisting of an initial negative peak followed by a positive peak; type N (4 of 24; 16.7%) showing a negative peak only, and type P (4 of 24; 16.7%) showing a positive peak only. The latencies ranged from 48.2 to 102.3 ms (mean, 65.5 ms) for negative peaks and 70.2 to 122.0 ms (mean, 95.2 ms) for positive peaks. In all patients, the basal temporal language area was associated with at least 1 CCEP, either as a stimulated region or a recorded region (11 of 24; 45.8%). CONCLUSION: These data indicate that there is a neural connection between bilateral BTRs. In consideration of the involvement of the basal temporal language area, we speculate that these responses may reflect some physiological connections between bilateral BTRs.

A substantial number of Rasmussen syndrome patients have increased IgG, CD4+ T cells, TNFalpha, and Granzyme B in CSF.

PURPOSE: We studied the immunologic molecules in cerebrospinal fluid (CSF) and discussed their evolutional changes in pediatric patients with Rasmussen syndrome (RS). METHODS: CSF samples collected from 27 patients with RS (average onset age, 7.5 +/- 5.6 years) were studied. Cell count, protein, glucose, albumin, chloride, and immunoglobulin G (IgG) levels were measured by conventional methods. Surface markers of lymphocytes in CSF were examined by a cell sorter. Granzyme B, interferon gamma (IFNgamma), interleukin 4 (IL-4), tumor necrosis factor alpha (TNFalpha), and IL-12 in CSF were quantitated by enzyme-linked immunosorbent assay (ELISA). Autoantibodies against GluR epsilon2 (NR2B) were examined by immunoblot. RESULTS: The data of the first CSF examination showed that IgG levels (Mann-Whitney U test, p < 0.01), CD4(+) T cells (p = 0.02), TNFalpha levels (p < 0.01), and Granzyme B levels (p < 0.01) were elevated compared with disease controls. White blood cell count, IFNgamma level, IL-12 level, and Granzyme B level were elevated, especially in the early stage of disease. CD4(+) T cells, CD8(+) cells, CD3(+) T cells, IgG levels, and TNFalpha levels were elevated at all stages of disease evolution. Protein levels and albumin levels were elevated in the progressed stage. Autoantibodies against GluR epsilon2 (NR2B) (IgG) were found in 50% of patients in the early stage, and the positive rate was low at the progressed stage. DISCUSSION: The present findings suggest that complex pathophysiologic mechanisms involving CD4(+) T cells and CD8(+) T cells change evolutionally during the progression of RS. A crucial cytotoxic process occurs in the early stage, and declines in the progressed stage.

[Acute limbic encephalitis and NMDA type-glutamate receptor].

We compared clinical characteristics and autoantibodies against GluRepsilon2 between 95 patients with nonparaneoplastic non-herpetic acute limbic encephalitis (NPNHALE) and 19 patients with non-herpetic acute encephalitis accompanying ovarian teratoma (NHAE-OT). Onset age (mean +/- SD) was 27.7 +/- 18.6 years old in NPNHALE, 27.5 +/- 6.5 in NHALE-OT. Preceding factors were found in 63.8% of patients with NPNHALE and 89.5% of patients with NHALE-OT (Fisher's exact test, p = 0.025), and major preceding factors were upper respiratory infections or fever in both groups. Symptoms at the onset were disorder of behavior and talk > seizures > impairment of consciousness in NPNHALE, and disorder of behavior and talk > seizures > disorientation in NHALE-OT. Symptoms at the acute stage were similar between NPNHALE and NHAE-OT, but duration of hospital stay was longer in NHAE-OT (209.0 days) than NPNHALE (87.5 days) (Mann Whitney test, p<0.0001). At the onset, cell counts in CSF were 51.6 +/- 66.4/mm3 and protein levels were 35.4 +/- 14.7 mg/dl, and IgG levels were 6.6 +/- 4.2 mg/dl in NHAE-OT, and these data were not significantly different between NPNHALE and NHAE-OT. In acute stage, autoantibodies against whole molecule of GluRepsilon2 in CSF were detected in 51.8% (29/56) of adult NPNHALE, and 40% (6/15) of NHAE-OT patients by immunoblot. These autoantibodies in both groups included epitopes to n-terminal of GluRepsilon2. Antibodies against NMDAR complex (Dalmau's method) in CSF were detected in 90.9% (10/11) of NHAE-OT patients.

Bilateral symmetric tonic posturing suggesting propagation to the supplementary motor area in a patient with precuneate cortical dysplasia.

We report a patient manifesting seizures with bilateral symmetric tonic posturing, which were markedly reduced after resection of the left precuneus. A 16-year-old man had sudden onset, complex partial seizures with bilateral symmetric tonic posturing since the age of eight years. Magnetic resonance fluid-attenuated inversion-recovery imaging revealed a hyperintense lesion in left precuneus. In almost all focal seizures recorded during an invasive EEG evaluation, ictal onset was detected from the inferomesial aspect of the lesion, but fast paroxysmal discharges from the ipsilateral supplementary motor area (SMA) were observed just before the clinical onset. After surgical excision of the EEG onset zone, including the lesion, seizure frequency was markedly (> 95%) reduced. By the 20th month after surgery, there were only brief nocturnal seizures involving slight elevation of both shoulders and slight abduction of both arms, with preservation of consciousness occurring once every few days. Invasive EEG findings and surgical outcome suggested that the epileptic activity originating from the epileptogenic zone may have propagated to the symptomatogenic zone including mainly the ipsilateral SMA. In summary, we report an interesting case of bilateral symmetric tonic posturing suggesting propagation to the SMA. MRI and invasive EEG confirmed the epileptogenic focus as a precuneate cortical dysplasia lesion.[Published with video sequences].

Usefulness of 123I-iomazenil single-photon emission computed tomography in discriminating between mesial and lateral temporal lobe epilepsy in patients in whom magnetic resonance imaging demonstrates normal findings.

OBJECT: To provide greater accuracy in determining the epileptogenic zone during preoperative evaluation, the authors retrospectively examined 123I-iomazenil single-photon emission computed tomography (IMZ SPECT) studies obtained in patients with temporal lobe epilepsy (TLE) in whom there was no evidence of an abnormality on magnetic resonance (MR) images. METHODS: Twelve patients, seven with mesial TLE (MTLE) and five with lateral TLE (LTLE), satisfied the criteria for inclusion in the study. The IMZ SPECT findings in these patients were reviewed retrospectively, and a comparison was made between findings in patients with MTLE and those in patients with LTLE. RESULTS: The IMZ SPECT studies demonstrated decreased IMZ uptake in the ipsilateral mesial temporal region and the anterobasal temporal lobe in all patients who had MTLE on only one side. On the other hand, IMZ SPECT examinations revealed low IMZ uptake in the ipsilateral lateral temporal lobe in four of five patients with LTLE in whom abnormal findings were restricted to the lateral neocortex. In the remaining patient with LTLE, abnormally low IMZ uptake was found in both mesial and lateral temporal lobes, although pure LTLE was diagnosed by an invasive electroencephalographic evaluation; this patient's habitual seizures continued even after temporal lobectomy, although his mesial structures were spared. CONCLUSIONS: The authors report characteristics of IMZ SPECT findings that differed between patients with MTLE and those with LTLE. The IMZ SPECT examinations proved useful for preoperative evaluation and, to a certain extent, for discrimination between MTLE and LTLE in cases in which MR imaging demonstrated normal findings. The results of this study suggest that IMZ SPECT findings may reflect localization of the epileptogenic zone.

Patients with a sodium channel alpha 1 gene mutation show wide phenotypic variation.

We investigated the roles of mutations in voltage-gated sodium channel alpha 1 subunit gene (SCN1A) in epilepsies and psychiatric disorders. The SCN1A gene was screened for mutations in three unrelated Japanese families with generalized epilepsy with febrile seizure plus (GEFS+), febrile seizure with myoclonic seizures, or intractable childhood epilepsy with generalized tonic-clonic seizures (ICEGTC). In the family with GEFS+, one individual was affected with panic disorder and seizures, and another individual was diagnosed with Asperger syndrome and seizures. The novel mutation V1366I was found in all probands and patients with psychiatric disorders of the three families. These results suggest that SCN1A mutations may confer susceptibility to psychiatric disorders in addition to variable epileptic seizures. Unidentified modifiers may play critical roles in determining the ultimate phenotype of patients with sodium channel mutations.

[Autoantibodies against glutamate receptors in patients with encephalitis].

We examined autoantibodies against GluRepsilon2 in patients with acute encephalitis, who were categorized into localized encephalitis and widespread encephalitis. Patients with localized encephalitis are defined as patients showing psychic symptoms (illusions, anxiety and distraction etc.), solitary seizures and/or very mild impairment of consciousness in the initial stage. Patients with widespread encephalitis are defined as patients showing a profound loss of consciousness and or convulsive status in the initial stage. In 24 patients with localized encephalitis, immunoglobulin (Ig) M autoantibodies against GluRepsilon2 tended to appear in CSF in the acute stage (0-20 days after onset of neurological symptoms) or recovery stage (21-60 days after onset of neurological symptoms) of encephalitis. In 22 patients with widespread encephalitis, IgM autoantibodies against GluRepsilon2 in CSF tended to appear in the recovery stage (21-60 days after onset of neurological symptoms) or chronic stage (>60 days after onset of neurological symptoms) of encephalitis. All patients with localized encephalitis had autoantibodies to the extracellular N epitope. However, no patients with widespread encephalitis had autoantibodies to the extracellular N epitope in acute stages. These data may suggest that GluR autoimmunity contributes to the onset of localized encephalitis.