Cha Gon Lee

The role of ketogenic diet in the treatment of refractory status epilepticus

Ketogenic diet (KD) is known to be effective in intractable epilepsy. However, the role of KD in refractory status epilepticus (RSE) has not been well described. The aim of this study is to explore the role of KD in patients with RSE. We retrospectively reviewed the medical records of four children and one adult with RSE between October 2006 and August 2010. All presented with status epilepticus (SE) that was presumed to be associated with viral encephalitis. After we failed to control the seizures with standard measures for SE, we tried KD. The overall seizure frequency decreased to <50% of baseline in median eight (1–19) days. At one month of KD, two patients were seizure‐free, one patient showed >90% seizure reduction, and the others had >75% decrease without generalized seizures. With improvement in the RSE, we were able to taper the antiepileptic drugs (AEDs) and wean patients from prolonged mechanical ventilation. The adverse events of KD in RSE included aspiration pneumonia, gastroesophageal reflux, constipation, and hypertriglyceridemia. Those results demonstrate that KD can be a valuable therapeutic option for patients with RSE.

Clinical features and genetic analysis of children with hyperekplexia in Korea.

Hyperekplexia is a rare inherited neurologic disorder that is characterized by hypertonia and an exaggerated startle response to sudden external stimuli. Until now, 5 genes are known to be associated with hyperekplexia: GLRA1, SLC6A5, GLRB, GPHN, and ARHGEF9. In this report, we performed a clinical and genetic analysis of 4 Korean children with hyperekplexia. Two patients had typical clinical manifestations of hyperekplexia that initially were misdiagnosed as epilepsy. Direct sequencing of the GLRB and GLRA1 genes revealed 2 novel mutations, GLRB c.298-1G>A and c.1028C>T (p.S343F), in patient 1 and 1 novel mutation, GLRA1 c.895C>T (p.R299X), in patient 2. The other 2 familial cases, patients 3 and 4, exhibited startle responses, which appeared at the age of 1 year, and had global developmental delay. Those patients showed negative results for the 5 genes.

Clinical outcome of acute necrotizing encephalopathy in related to involving the brain stem of single institution in Korea

Purpose Acute necrotizing encephalopathy (ANE) is a fulminant disease of the brain characterized by bilateral thalamic lesions, and is prevalent among children in East Asia. The prognosis of ANE is usually poor with a high mortality rate and neurological sequelae. This study aimed to delineate the clinical characteristics and prognostic factors of ANE. Methods We retrospectively analyzed clinical data of 399 pediatric patients with encephalitis who were admitted to Samsung Medical Center from December 1998 to March 2011. We enrolled ten patients (11 cases) with ANE and analyzed their demographic, clinical, and neuroimaging data. The location and extent of the brain regions were checked based on fluid-attenuated inversion recovery, T1-, and T2-weighted imaging findings; the presence of contrast enhancement, restricted diffusion, and hemorrhage. Results Ten patients were identified, including one patient with two episodes. The median age of onset was 1.5 years (0.4-8.4 years). The mortality rate was 40%, and only 30% of patients survived without neurological sequelae. The definite involvement of the brainstem on brain magnetic resonance imaging was significantly correlated with mortality (P=0.04). Conclusion Broad and extensive brainstem involvement suggested the fulminant course of ANE. Early diagnosis of ANE before brainstem involvement, through careful identification of symptoms of brain dysfunction, may be the best way to achieve better neurological outcomes.

Brain abscess in Korean children: A 15-year single center study

Purpose A brain abscess is a serious disease of the central nerve system. We conducted this study to summarize the clinical manifestations and outcomes of brain abscesses. Methods A retrospective chart review of pediatric patients diagnosed with brain abscesses from November 1994 to June 2009 was performed at Samsung Medical Center, Seoul, Korea. Results Twenty-five patients were included in this study. On average, 1.67 cases per year were identified and the median age was 4.3 years. The common presenting clinical manifestations were fever (18/25, 72%), seizure (12/25, 48%), altered mental status (11/25, 44%), and signs of increased intracranial pressure (9/25, 36%). A total of 14 (56%) patients had underlying illnesses, with congenital heart disease (8/25, 32%) as the most common cause. Predisposing factors were identified in 15 patients (60%). The common predisposing factors were otogenic infection (3/25, 12%) and penetrating head trauma (3/25, 12%). Causative organisms were identified in 64% of patients (16/25). The causative agents were S. intermedius (n=3), S. aureus (n=3), S. pneumoniae (n=1), Group B streptococcus (n=2), E. coli (n=1), P. aeruginosa (n=1), and suspected fungal infection (n=5). Seven patients received medical treatment only while the other 18 patients also required surgical intervention. The overall fatality rate was 16% and 20% of patients had neurologic sequelae. There was no statistical association between outcomes and the factors studied. Conclusion Although uncommon, a brain abscess is a serious disease. A high level of suspicion is very important for early diagnosis and to prevent serious consequences.

Clinical and ictal characteristics of infantile seizures: EEG correlation via long-term video EEG monitoring.

PURPOSE The semiology of infantile seizures often shows different characteristics from that of adults. We performed this study to describe clinical and ictal characteristics of infantile seizures at less than two years of age. METHODS A retrospective study was done for infants with epilepsy (ages: 1-24months) who underwent long-term video electroencephalography (EEG) monitoring at Samsung medical center between November 1994 and February 2012. We analyzed the clinical and ictal characteristics of the 56 cases from 51 patients. RESULTS In 69% of the patients, the seizure onset was before six months of age and the etiology was symptomatic in one third of the patients. Twelve seizure types were identified; spasms (24%), unilateral motor seizures (18%), and generalized tonic seizures (15%) were the three frequent types of seizure. All partial seizures were well correlated with the partial-onset ictal EEG, however 19.4% (7/36) of clinically generalized seizures revealed partial-onset ictal EEG. About one-thirds (4/11) of generalized tonic seizures had its ictal onset on unilateral or bilateral frontal areas and two out of seven generalized myoclonic seizures showed unilateral frontal rhythmic activities. Hypomotor seizures mainly arose from the temporal areas and hypermotor seizures from the frontal regions. CONCLUSIONS Even though most of the seizure semiology of infants is well correlated with ictal EEG, some of the generalized tonic seizures or myoclonic seizures revealed partial-onset ictal EEG suggesting localized epileptic focus. Accurate definition of seizures via video EEG monitoring is necessary for proper management of seizures in infancy, especially in some clinically generalized seizures.

Multi-gene panel testing in Korean patients with common genetic generalized epilepsy syndromes

Genetic heterogeneity of common genetic generalized epilepsy syndromes is frequently considered. The present study conducted a focused analysis of potential candidate or susceptibility genes for common genetic generalized epilepsy syndromes using multi-gene panel testing with next-generation sequencing. This study included patients with juvenile myoclonic epilepsy, juvenile absence epilepsy, and epilepsy with generalized tonic-clonic seizures alone. We identified pathogenic variants according to the American College of Medical Genetics and Genomics guidelines and identified susceptibility variants using case-control association analyses and family analyses for familial cases. A total of 57 patients were enrolled, including 51 sporadic cases and 6 familial cases. Twenty-two pathogenic and likely pathogenic variants of 16 different genes were identified. CACNA1H was the most frequently observed single gene. Variants of voltage-gated Ca2+ channel genes, including CACNA1A, CACNA1G, and CACNA1H were observed in 32% of variants (n = 7/22). Analyses to identify susceptibility variants using case-control association analysis indicated that KCNMA1 c.400G>C was associated with common genetic generalized epilepsy syndromes. Only 1 family (family A) exhibited a candidate pathogenic variant p.(Arg788His) on CACNA1H, as determined via family analyses. This study identified candidate genetic variants in about a quarter of patients (n = 16/57) and an average of 2.8 variants was identified in each patient. The results reinforced the polygenic disorder with very high locus and allelic heterogeneity of common GGE syndromes. Further, voltage-gated Ca2+ channels are suggested as important contributors to common genetic generalized epilepsy syndromes. This study extends our comprehensive understanding of common genetic generalized epilepsy syndromes.