Safe and effective use of the ketogenic diet in children with epilepsy and mitochondrial respiratory chain complex defects

PURPOSE: To evaluate the clinical efficacy and safety of the ketogenic diet (KD) for patients with intractable childhood epilepsy and mitochondrial respiratory chain (RC) complex defects. METHODS: A retrospective analysis evaluated outcomes in 14 children with intractable epilepsy and RC complex defects who were treated with the classic KD involving a 4:1 lipid to nonlipid ratio (% by weight), but without an initial fast and fluid restriction. Outcome measures included seizure frequency, electroencephalography (EEG) findings, the number of antiepileptic drugs, and adverse reactions. RESULTS: Of the 14 patients, 9 had Complex I defects, 1 had a Complex II defect, 3 had Complex IV defects, and 1 had combined Complex I and IV defects. Two patients with Complex IV defects showed clinical progress compatible with the Leigh disease. The epileptic diagnoses were as follows: 5 patients were diagnosed with infantile spasms, 4 with the Lennox-Gastaut syndrome, 1 with the Landau-Kleffner syndrome, 1 with nonspecific generalized seizure disorder, and 3 with partial seizure disorder. The study found that 7 patients became seizure-free after commencing the KD, three of whom successfully completed the diet without relapse. One patient with a greater than 90% seizure reduction, and 2 patients with seizure reductions between 50% and 90%, remained on the diet. Four patients, including two diagnosed with the Leigh disease, did not show any favorable responses to the diet or ceased the diet due to complications. CONCLUSIONS: The KD was a safe and effective therapy for seizures in children with intractable epilepsy and RC complex defects.     

Seizures in multiple sclerosis

PURPOSE: In patients with multiple sclerosis (MS), epileptic seizures occur more frequently than in the general population. The aim of this study was to analyze clinical characteristics of epilepsy in patients with MS, potential correlation between the semiology of seizures, EEG and magnetic resonance imaging (MRI) findings in these patients, as well as to examine the response to anticonvulsant therapy. METHODS: In a series of 268 consecutive patients with definite MS hospitalized at the Institute of Neurology, Belgrade, we identified 20 (7.5%) patients with seizures or epilepsy. All patients with seizures or epilepsy were submitted to standard EEG and brain MRI with gadopentetate dimeglumine. RESULTS: In four patients, epilepsy occurred 1-5 years before other clinical manifestations of MS. Eight patients had seizures only during MS relapses (provoked seizures). In two of them, seizures were the only manifestations of relapse. In 12 patients, seizures occurred regardless of the phase of MS (chronic epilepsy). In the majority of patients, seizures were partial with secondary generalization. Five patients experienced episodes of status epilepticus, and they all had dementia. Abnormal EEG pattern was found in 11 patients. Brain MRI disclosed cortical-subcortical lesions in nine patients and focal cortical atrophy in one, whereas in the remaining patients, findings were inconclusive. Probable EEG-MRI-seizure type correlation existed in 10 patients. CONCLUSIONS: Our data suggest that epilepsy may represent an initial symptom of MS and a single clinical manifestation of a relapse, and further support the assumption of the existing correlation between the presence of cortical-subcortical lesions and epileptic seizures or epilepsy in patients with MS.     

Over-interpretation of electroclinical and neuroimaging findings in syncopes misdiagnosed as epileptic seizures.

Syncope and epileptic seizures share some common clinical characteristics that may complicate the diagnostic process. In clinical practice, syncope is frequently misdiagnosed as an epileptic seizure and consequently treated with antiepileptic drugs. In this study, we identified 57 patients with syncope (diagnosis based on accepted criteria) who had come to our unit with a previous diagnosis of definite epilepsy in 30 cases (syncope misdiagnosed as epileptic seizures, SMS), or suspected epilepsy in the remaining 27 cases (unrecognized syncope, US). We attempted to identify factors underlying misdiagnosis by reviewing clinical findings, particularly potentially confounding features, and EEG/neuroimaging data. Finally, we compared these two groups of patients to search for crucial elements that had led to misdiagnosis. Although some clinical elements were found to be confounding in both groups, it was the interpretation of the EEG and MRI findings, particularly when combined with the confounding clinical features that constituted the main reasons for misdiagnosis.     

Comparative clinical characteristics of early- and adult-onset multiple sclerosis patients with seizures

Multiple sclerosis (MS) and epilepsy are common disorders, the co-occurrence of which has been of considerable interest. This study aimed to evaluate the prevalence and clinical features of epileptic seizures in patients with definite MS including those with pediatric onset (≤16 years of age). Out of 2,300 patients with definite MS followed in our outpatient clinic, 36 with epileptic seizures were identified. In this cohort, 8 out of 146 pediatric cases had seizures. The clinical and demographic features of the patients were recorded. Multiple logistic regression model with the occurence of seizures as the dependent variable was performed to identify the risk factors for seizure occurrence in MS patients. The prevalence of epileptic seizures was 1.5 % in definite MS patients, 1.3 % in adult-onset (comparable to seizure prevalence in the general population) and 5.5 % in pediatric MS patients (≤16 years old). Twenty-six of 36 (72 %) patients with MS and epilepsy developed recurrent seizures after the first epileptic seizure. Mean annual relapse rate (p ≤ 0.001), mean expanded disability status scale (EDSS) score (p = 0.004) and the ratio of patients with pediatric onset (p = 0.01) were higher in MS patients with seizures. In the multiple logistic regression analysis, age at MS onset and EDSS at the last examination were found to be predictors of seizure occurrence. Occurrence of seizures during the clinical course of MS appears to be associated with early-onset and increased disease severity and might be coincidental in adults.     

The relative influence of epileptic EEG discharges, short nonconvulsive seizures, and type of epilepsy on cognitive function

PURPOSE: This study addressed whether cognitive impairment in children with epilepsy is caused by disease-related stable factors, such as the type of epilepsy, or by acute effects of paroxysmal epileptic activity such as epileptic EEG discharges. We studied a nonselected group with short nonconvulsive seizures, as these seizures may elude detection and may therefore persist over a longer period. In this group, the diagnostic issue is to differentiate between the combined effects of several epilepsy-related factors on cognition. METHODS: All children were assessed with 32-channel EEG, synchronized with a computerized cognitive test system and a video-monitoring system. Recording time was 2 h. The primary inclusion criteria were unclear seizures and fluctuations in cognitive performance and/or frequent epileptic EEG discharges in a recent EEG. RESULTS: One hundred fifty-two patients met the inclusion criteria; 31 patients appeared not to have a diagnosis of epilepsy and were used as a nonepilepsy control group. Our results show that type of epilepsy has an impact on stable cognitive functions, such as educational achievement. Paroxysmal epileptic activity (acute effects of seizures and epileptic EEG discharges) affects primarily transient mechanistic cognitive processes (alertness, mental speed). CONCLUSIONS: These results suggest that the effects of paroxysmal epileptic activity on transient cognitive mechanisms may accumulate over time and consequently affect the more stable aspects of cognitive function such as educational achievement. The clinical relevance is that early detection of the cognitive impact of seizure-related activity and subsequent treatment may prevent its detrimental impact on cognitive and educational development.     

Comparison of heart rate variability parameters during complex partial seizures and psychogenic nonepileptic seizures

Purpose: Psychogenic nonepileptic seizures (PNES) superficially resemble epileptic seizures. Little is known about ictal autonomic nervous system (ANS) activity changes in epilepsy and PNES. This study compares ictal heart rate variability (HRV) parameters as a reflection of ANS tone in epileptic seizures and PNES, and explores differences between interictal and ictal ANS tone in both patient groups. Methods: Ictal HRV parameters were extracted from single‐lead electrocardiography (ECG) data collected during video–electroencephalography (EEG) recordings of 26 patients with medically refractory temporal lobe epilepsy and 24 age‐ and sex‐matched patients with PNES. One seizure per patient in a resting, wake, supine state was analyzed. Interictal ECG data were available for comparison from 14 patients in both groups. HRV parameters in time and frequency domains were analyzed (low frequency [LF], high frequency [HF], standard deviation of all consecutive normal R wave intervals [SDNN], square root of the mean of the sum of the squares of differences between adjacent normal R wave intervals [RMSSD]). CVI (cardiovagal index), CSI (cardiosympathetic index), and ApEn (approximate entropy) were calculated from Lorenz plots. Key Findings: There were significant differences between ictal HRV measures during epileptic and nonepileptic seizures in the time and frequency domains. CSI (p < 0.001) was higher in epileptic seizures. Time interval between two consecutive R waves in the ECG (RR interval) (p = 0.002), LF (p = 0.02), HF (p = 0.003), and RMSSD (p = 0.003) were significantly lower during epileptic seizures. Binary logistic regression yielded a significant model based on the differences in CSI classifying 88% of patients with epilepsy and 73% of patients with PNES correctly. The comparison between resting and ictal states in both seizure disorders revealed significant differences in RR interval (epilepsy p < 0.001, PNES p = 0.01), CSI (epilepsy p < 0.001, PNES p = 0.02), HF (epilepsy p = 0.002, PNES p = 0.03), and RMSSD (epilepsy p = 0.004, PNES p = 0.04). In patients with epilepsy there were also significant differences in ictal versus interictal mean values of ApEn (p = 0.03) and LF (p = 0.04). Although CSI was significantly higher, the other parameters were lower during the seizures. Stepwise binary regression in the 14 patients with epilepsy produced a significant model differentiating resting state from seizures in 100% of cases. The same statistical approach did not yield a significant model in the PNES group. Significance: Our results show greater ANS activation in epileptic seizures than in PNES. The biggest ictal HRV changes associated with epileptic seizures (CSI, HF, and RMSSD) reflect high sympathetic system activation and reduced vagal tone. The reduced ApEn also reflects a high sympathetic tone. The observed ictal alterations of HRV patterns may be a more specific marker of epileptic seizures than heart rate changes alone. These altered HRV patterns could be used to detect seizures and also to differentiate epileptic seizures from PNES. Larger studies are justified with intergroup and intragroup comparisons between ictal and resting states.     

Spasms in children with definite and probable mitochondrial disease.

The diagnosis of mitochondrial encephalomyopathies is complex and a system for classification of the diagnosis as definite, probable, and possible has been proposed. The objective of this study was to explore the spectrum of epileptic disorders associated with probable and definite mitochondrial disease in children using this classification system. The patient population with mitochondrial disease and epilepsy was selected from a tertiary care children's hospital. Interictal electroencephalograms and video-EEG recordings were used to characterize seizure types. Ten children fulfilled the criteria for probable or definite mitochondrial disease and had epilepsy. Four had siblings with a similar clinical phenotype. Spasms were the most common seizure type and were the initial seizure type in seven patients and two siblings. Four patients had only partial seizures, with or without generalization, and one patient had seizures that were difficult to classify. Blood lactate concentrations were elevated consistently in patients with partial seizures alone but were occasionally normal in children with spasms. Spasms were the most common presenting seizure type in children with probable and definite mitochondrial disease.     

Absence seizures in the first 3 years of life: an electroclinical study of 46 cases

Purpose: Early onset absence seizures have been considered a rare heterogeneous group with a poor prognosis. Only few patients may be categorized into well‐known syndromes. We have evaluated electroclinical features, evolution, and the nosologic boundaries of early onset absence seizures. Methods: Forty‐six neurologically normal patients with absence seizures associated with bilateral, synchronic, or asynchronic, and symmetric or asymmetric spike‐and‐wave paroxysms with onset in the first 3 years of life were included. Patients with abnormal neurologic examination and brain imaging were excluded from the study. Key Findings: In our study, 39 patients met the clinical and electroencephalography (EEG) criteria of well‐defined epileptic syndromes. Childhood absence epilepsy was found in 11 patients, benign myoclonic epilepsy in infancy in 18 patients, eyelid myoclonic epilepsy in 4, and epilepsy with myoclonic absences in 6. We did not find clinical and EEG criteria of well‐recognized epileptic syndromes in seven children. Nine of 11 patients with simple absence seizures became seizure free. All these patients had normal neurologic and neuropsychological evaluations. Of the 35 patients who had absence seizures associated with myoclonic seizures, 20 became seizure free. Fifteen of 35 children continue having seizures. At the last visit, 20 of these 35 patients had normal neurologic and neuropsychological evaluations, 11 presented with mild mental retardation, and 4 with severe mental retardation. Significance: Epilepsies with absence seizures of early onset are relatively uncommon. Most of the patients had well‐defined epileptic syndromes with a variable evolution. The evolution depended on the epileptic syndromes.     

Clinical evaluation of the patients with epilepsy following febrile convulsions

We studied clinical, EEG and developmental features of 46 epileptic children following febrile convulsions. Incidence of developing epilepsy was 9.9 percent. Eleven patients (group G) out of 46 had generalized epileptic seizures, and 34 patients (group P) had partial seizures. Febrile convulsions of early onset, partial seizures and postictal neurological symptoms were more striking in group P (p less than 0.05), whereas febrile convulsions of late onset and prolonged seizures were slightly dominant in group G. And EEG abnormalities were more frequent in group P (p less than 0.05). Group P patients had significant number of risk factors (complex features of febrile convulsions) than group G patients (p less than 0.01). The interval between the last febrile convulsion and subsequent epileptic seizures was shorter in group G (p less than 0.01). Although subsequent epileptic seizures were well controlled in the both groups (91% in group G and 82% in group P), intractable seizures were recognized in 9% of group P patients. The patients who had risk factors of prolonged seizures, postictal neurological symptoms and early onset manifested poor controlled epileptic seizures (p less than 0.01). Motor or mental deficits were more frequently associated with group P: in some patients they had been observed before the onset of febrile convulsions. These results suggest that pathogenesis of epilepsy following febrile convulsions may be different among various seizure types of subsequent epilepsy. And the risk factors during febrile convulsions may be related to the prognosis of subsequent epileptic seizures as well as the incidence of developing epilepsy.     

Multiple sclerosis and epilepsy. An analysis of 14 case histories

Fourteen of 330 patients with the clinical and laboratory supported definite diagnosis of Multiple Sklerose (MS) had epileptic seizures. The epilepsy of six patients probably originates from the MS. Four patients respectively suffered from genuin epilepsy or symptomatic epilepsy caused by other diseases than the MS. Most patients had GM, two GM and focal motor fits and one uncinatus fits. An epileptic focus in the EEG was evident in two patients. MRI- and CCT-scans frequently showed extensive cortex-neighboured lesions and multiple subcortical demyelination, especially localized in the temporal lobe. Epileptic seizures as a symptom of MS are very seldom. The longer the interval from the first episode of the MS to the first epileptic seizure the more probable epilepsy is caused by other reasons than the MS.     

24小时动态脑电图癔病诱发试验对癔病与癫痫的鉴别诊断价值

目的寻找鉴别癔病性发作与癫痫发作的有效方法。方法对９６例发作性疾病患者进行２４小时动态脑电图监测及癔病诱发试验（ＡＥＥＧ－ＨＰＴ）研究。结果难治性癫痫疑伴癔病组（１８例）、癔病或癫痫发作诊断不定组（３６例）、癫痫组（１８例）、癔病组（２４例）４组中癔病诱发试验阳性率分别为７７．８％、６６．７％、５．６％、９１．７％；记录到非诱发下自发发作（癫痫或癔病）分别为３、７、３、１例；记录到发作间期癫痫性放电分别为１６、１８、１７、２例。９６．０％的患者明确诊断。结论ＡＥＥＧ－ＨＰＴ是鉴别癔病与癫痫发作的有效方法之一。     

Genetic literacy series: genetic epilepsy with febrile seizures plus

Genetic epilepsy with febrile seizures plus (GEFS+) is a familial epilepsy syndrome in which affected individuals within a family typically have a variety of epilepsy phenotypes, varying from simple febrile seizures and febrile seizures plus with a good outcome to severe epileptic encephalopathies. Here, we review the spectrum of epilepsy phenotypes, the genetic architecture of GEFS+, and the implicated genes. Using an illustrative clinical case study, we describe important steps in managing patients with GEFS+: making the diagnosis of GEFS+, appropriate genetic testing, and counselling.     

Epilepsy in Peroxisomal Diseases

Summary: Purpose: To clarify the electroclinical manifestation of epileptic seizures and the evolution of epilepsy in patients with peroxisomal diseases. Methods: Retrospective review of the medical records and EEGs of 14 patients with peroxisomal diseases: seven with Zellweger syndrome (ZS), two with neonatal adrenoleuko-dystrophy (NALD), two with acyl-CoA oxidase deficiency (AOXD), two with bifunctional enzyme deficiency (BFED), and one with rhizomelic chondrodysplasia punctata (RCDP). The diagnoses were made by biochemical analysis and pathological examinations in our laboratory. Results: Patients manifested serious neurologic deficits in the neonatal period or in early or late infancy. Patients with ZS or AOXD had partial motor seizures originating in the arms or legs or corners of the mouth. Their seizures did not culminate in generalized tonic-clonic seizures and were easily controlled by antiepileptic drugs (AEDs). Interictal EEGs of the patients with ZS showed infrequent bilateral independent multifocal spikes, predominantly in the frontal motor cortex and its surrounding regions. The EEGs of patients with AOXD showed interictal fast theta activity, predominantly in the frontocentral regions. Patients with BFED also had partial motor seizures in early infancy, but the seizures were intractable, evolving in one case to myoclonic seizures. Interictal EEGs of patients with BFED showed bilateral independent multifocal spikes that evolved to bilateral diffuse high-voltage slow waves in one case and to a hypsarythmic pattern in another case as the disease progressed. Patients with NALD had intractable tonic seizures or epileptic spasms. Interictal EEGs showed high-voltage slow waves and bilateral independent multifocal spikes, evolving in one patient to a flat pattern. The patient with RCDP, whose interictal EEGs showed frequent multifocal independent spikes, did not have epileptic seizures. Conclusions: The age of epilepsy onset or the duration of survival is related to the types of seizures occurring in patients with peroxisomal diseases. Neonates or young infants usually have partial motor seizures (facial twitching or clonic convulsions of the arms or legs) of various multifocal origins. Older infants may have generalized seizures at the onset of the disease or evolutionally. Seizure intractability is usually less severe in patients with ZS or AOXD than in patients with NALD or BFED. There is no relation between the electroclinical characteristics of epilepsy and the genetic complementation groups in peroxisomal diseases.     

Prevalence and Prognosis of Epilepsy in Patients with Multiple Sclerosis

An analysis of 599 clinically definite multiple sclerosis (MS) patients including all known cases of the southern province of Finland in January 1, 1979 revealed epileptic seizures in 21 (3.5%) patients. On that date, 12 patients needed treatment (2.0%). The age-adjusted prevalence of active epilepsy was significantly higher than that in the general population. The percentage of partial seizures (67%) was significantly increased in proportion to a series of 100 adult epilepsy patients, with a comparable age distribution. In 10 patients (including three patients with symptomatic epilepsy), the attacks appeared before the MS symptoms. The mean follow-up after the first seizures was 19.3 years. In 10 patients, the seizures disappeared totally during the surveillance until September 1985. Our results show an increased comorbidity between MS and epilepsy. In most cases, however, the prognosis of epilepsy was good and there seemed not to be any clear correlation between the severity of MS and epilepsy.     

Long-Term Course of Childhood Epilepsy with Intractable Grand Mal Seizures

Abstract: Twenty-nine children with childhood epilepsy characterized by frequent grand mal (generalized tonic-clonic) seizures in spite of maximal doses of antiepileptic drugs and by an early onset of seizures (before 1 :year of age) were followed up for more than 5 :years. The children were divided into 3 :groups: severe myoclonic epilepsy in infancy (SME), no SME, and intractable childhood epilepsy with generalized tonic-clonic seizures (GTC). In all the 3 :groups, the grand mal seizures persisted, whereas the other types of seizures tended to disappear as the patients aged, and the prognosis for mental development was poor. In the majority of cases in all the 3 :groups, the waking grand mal seizures altered to sleep grand mal seizures with aging. Two pairs of monozygotic twins with SME suggested that genetic factors play a role in this epileptic syndrome. Intractable childhood epilepsy with GTC is distinguished by the absence of other types of generalized seizures. It cannot be regarded as an epileptic syndrome, but its pathogenesis and treatment require further studies.     

Diagnostic issues and treatment of cryptogenic or symptomatic generalized epilepsies

To clarify the diagnostic issues and treatment of patients with cryptogenic or symptomatic generalized epilepsies, not including West syndrome (WS), we investigated electroclinical change during the clinical course, and treatment effects in these patients. The selection criteria were minor generalized seizures as their main seizure type and diffuse epileptic discharges as their main EEG findings. Regarding EEG, we included EEGs that predominantly displayed multifocal spike-waves because of the inclusion of severe epilepsy with multiple independent spike foci (SE-MISF). We divided the subjects into two groups according to their main seizure types: Group A (54 patients) with brief tonic seizures and Group B (24 patients) with myoclonic seizures and/or atypical absences. The main epileptic syndromes were considered to be Lennox-Gastaut syndrome and SE-MISF in Group A, and epilepsy with myoclonic-astatic seizures in Group B. A history of WS was often seen in Group A, but it was exceptional in Group B. During the clinical course, seizure types did not basically change in Group A. EEG patterns were changeable in both groups. Although there was some overlap in electroclinical manifestations among epileptic syndromes, a transition between the two groups was not seen. High-dose valproate and ethosuximide were the most effective in Groups A and B, respectively. Long-term prognosis was significantly more favorable in Group B than in Group A.     

Epilepsy in middle-aged and elderly people: a three-year observation.

An analysis of the medical documentation and investigation of 130 cases of epilepsy diagnosed in a group of people over 50 years of age (average: 65.4 years) revealed that the most common type of seizure in the group studied was partial (66.2%), followed by seizures with secondary generalization (33.8%). Epilepsy was caused by cerebrovascular disease (50.8%) considerably more often in patients over 74 years of age, craniocerebral trauma in patients addicted to alcohol (13.1%), especially those under 65 years of age, primary or metastatic neoplastic disease (10.7%), and others. The authors wish to draw attention to the leukoaraiosis factor, which might be the proepileptogenic cause of epilepsy recognized in the group of patients over 74 years of age (56.5%) and is much more frequent in this group than in the group of patients under 65 years of age (1.6%). Moreover, some drugs, such as L-dopa and Baclofen, might have been related to the epileptic seizures. In 29 patients (22.3%) the definite cause of late-onset epilepsy was unknown. The authors suggest in such cases, both follow-up tomographic examination and careful clinical examinations. In the study group of patients with initially unknown seizure etiology, some diseases, such as cerebral tumor or colon and pancreatic neoplasm, were diagnosed during follow-up examination. These processes were revealed several months after the first epileptic seizure.     

Do Children with Benign Rolandic Epilepsy Have a Higher Prevalence of Migraine than Those with Other Partial Epilepsies or Nonepilepsy Controls?

PURPOSE: Prior studies have given conflicting data concerning the association of benign rolandic epilepsy of childhood (BREC) and migraine but were limited by lack of sensitive, diagnostic criteria for childhood migraine. By using revised International Headache Society (IHS-R) criteria, we compared the prevalence of migraine in children with BREC with that of those (a) with cryptogenic/symptomatic partial epilepsy and (b) without epilepsy. METHODS: Three cohorts of children, gender and age matched (within 1 year) were identified: (a) BREC, (b) cryptogenic/symptomatic partial epilepsy, and (c) no history of seizures. Parents were queried in a standardized interview about migraine and migraine equivalents in their child, and in either biologic parent. Migraine was defined by using the IHS-R (for children) and IHS criteria (for parents). Children with headache were divided into definite (meeting IHS-R criteria), probable (recurrent, throbbing headaches with nausea, vomiting, photophobia or phonophobia, not meeting IHS-R criteria), possible (recurrent headaches with throbbing character or associated nausea/vomiting), or nonmigraine groups. chi(2) analysis was used to determine whether the cohort with BREC had a higher prevalence of definite, definite or probable, or definite, probable, or possible migraines or migraine equivalents than the other two cohorts. RESULTS: Each cohort consisted of 53 children (mean age, 9.8-9.9 years, M/F ratio, 35:18). Those with BREC had higher rates of definite and probable (p = 0.05), of definite, probable, and possible migraine (p = 0.05), and of migraine equivalents excluding motion sickness (p < 0.005) than did those without seizures; however, they did not differ significantly from the cryptogenic/symptomatic partial epilepsy cohort. CONCLUSIONS: Partial epilepsy, regardless of etiology, is associated with higher rates of migraine in children. The pathophysiologic link between epilepsy and migraine is unknown.