Language and social functioning in children and adolescents with epilepsy.

Individuals with epilepsy have difficulties with social function that are not adequately accounted for by seizure severity or frequency. This study examined the relationship between language ability and social functioning in 193 children with epilepsy over a period of 36months following their first recognized seizure. The findings show that children with persistent seizures have poorer language function, even at the onset of their seizures, than do their healthy siblings, children with no recurrent seizures, and children with recurrent but not persistent seizures.

Design and implementation of the first randomized controlled trial of coenzyme CoQ₁₀ in children with primary mitochondrial diseases.

We report the design and implementation of the first phase 3 trial of CoenzymeQ₁₀ (CoQ₁₀) in children with genetic mitochondrial diseases. A novel, rigorous set of eligibility criteria was established. The trial, which remains open to recruitment, continues to address multiple challenges to the recruitment of patients, including widely condoned empiric use of CoQ₁₀ by individuals with proven or suspected mitochondrial disease and skepticism among professional and lay mitochondrial disease communities about participating in placebo-controlled trials.

Cyclocreatine treatment improves cognition in mice with creatine transporter deficiency.

The second-largest cause of X-linked mental retardation is a deficiency in creatine transporter (CRT; encoded by SLC6A8), which leads to speech and language disorders with severe cognitive impairment. This syndrome, caused by the absence of creatine in the brain, is currently untreatable because CRT is required for creatine entry into brain cells. Here, we developed a brain-specific Slc6a8 knockout mouse (Slc6a8-/y) as an animal model of human CRT deficiency in order to explore potential therapies for this syndrome.

Importance of muscle light microscopic mitochondrial subsarcolemmal aggregates in the diagnosis of respiratory chain deficiency.

The purpose of this study was to evaluate relationships between subsarcolemmal mitochondrial aggregates and electron transport chain deficiencies in skeletal muscle with the objective of establishing an association between mitochondrial accumulation and electron transport chain complex deficiency. We conducted a large-scale, retrospective study to evaluate factors associated with subsarcolemmal mitochondrial aggregates (percent) in pediatric patients who received muscle biopsies for suspected respiratory chain disorders. Patients were included if they had histochemical stains for assessment of mitochondrial pathology and had biochemical testing for muscle electron transport chain complex activities.

Enzyme inducing antiepileptic drugs are associated with mitochondrial proliferation and increased cytochrome c oxidase activity in muscle of children with epilepsy.

Purpose: To evaluate the effects of epilepsy-related factors associated with mitochondrial pathology and function in skeletal muscle of children with suspected mitochondrial disorders.

Methods: This case-control study evaluated patients and age-matched controls with muscle biopsies at Cincinnati Children's Hospital Medical Center obtained between January, 2000 and December, 2008.

Results: A total of 65 epilepsy patients and 65 age-matched controls met the inclusion criteria.

Creatine transporter (CrT; Slc6a8) knockout mice as a model of human CrT deficiency.

Mutations in the creatine (Cr) transporter (CrT; Slc6a8) gene lead to absence of brain Cr and intellectual disabilities, loss of speech, and behavioral abnormalities. To date, no mouse model of CrT deficiency exists in which to understand and develop treatments for this condition. The purpose of this study was to generate a mouse model of human CrT deficiency.

Self-esteem and symptoms of depression in children with seizures: relationships with neuropsychological functioning and family variables over time.

Purpose: To test over time the relationships of neuropsychological functioning to mental health in children following a first recognized seizure and, of primary importance, to determine if the strength of these relationships differs based on risk and protective factors.

Methods: In a larger prospective study, 135 children with a first seizure (ages 8-14 years) and 73 healthy sibling controls completed neuropsychological testing at baseline and 36 months. Structured telephone interviews were used to obtain data from children on mental health and family environment; major caregiving parents provided data on demographic and family variables.

The effect of temperament and neuropsychological functioning on behavior problems in children with new-onset seizures.

The present study is part of a larger project that seeks to identify factors that predict children's behavioral, social, and cognitive adaptation to epilepsy. Children with seizures are more likely to have internalizing and externalizing behavior problems than either healthy children or children with other chronic illnesses. The present research examines risk factors for behavior problems.

Seizure recurrence risk following a first seizure in neurologically normal children.

Purpose: To define seizure recurrence rates in normal children who had had a single seizure and to define electroencephalography (EEG) or magnetic resonance imaging (MRI) utility in predicting seizure recurrence.

Methods: We studied 150 children (6 to 14 years) with a first afebrile, unprovoked seizure. Inclusion criteria were: Normal physical and neurological examination, undergone EEG and MRI studies of the brain, and followed for at least 27 months.

Magnetic resonance imaging findings in children with a first recognized seizure.

This study characterized structural abnormalities associated with onset of seizures in children, using magnetic resonance imaging and a standardized classification system in a large prospective cohort. Two hundred eighty-one children aged 6-14 years completed magnetic resonance imaging within 6 months of their first recognized seizure. Most examinations were performed with a standardized, dedicated seizure protocol; all were scored using a standard scoring system.

Megalencephalic leukoencephalopathy with subcortical cysts: a third confirmed case with literature review.

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) causes early-onset, slowly progressive central nervous system white matter disease, macrocephaly, and later cognitive and motor decline. We describe brain structure in a patient with MLC and proven MLC1 mutations. A male, normal at birth, had macrocephaly at 6 months followed by developmental delay.

The relationship between sleep problems and neuropsychological functioning in children with first recognized seizures.

Epilepsy is associated with sleep disturbance, but little is known about how early this relationship develops and how it affects neuropsychological functioning. This study documented the frequency and types of sleep problems and examined how sleep problems are associated with seizures and neuropsychological functioning in 332 children following their first recognized seizure (ages 6-14) and in 225 sibling controls. Formal neuropsychological batteries were administered to all subjects.

Functional characterization of missense variants in the creatine transporter gene (SLC6A8): improved diagnostic application.

Creatine transporter deficiency is an X-linked mental retardation disorder caused by mutations in the creatine transporter gene (SLC6A8). So far, 20 mutations in the SLC6A8 gene have been described. We have developed a diagnostic assay to test creatine uptake in fibroblasts.

The association of MRI findings and neuropsychological functioning after the first recognized seizure.

Purpose: To explore relationships between MRI abnormalities of the brain and neuropsychological functioning in children who were evaluated following their first recognized seizure.

Methods: Subjects were children aged 6 to 14 years with a first recognized seizure within the past 3 months who participated in a larger prospective study of child adaptation. The 249 children with neuropsychological testing and neuroimaging were studied.

Temperament, family environment, and behavior problems in children with new-onset seizures.

Children with epilepsy, even those with new-onset seizures, exhibit relatively high rates of behavior problems. The purpose of this study was to explore the relationships among early temperament, family adaptive resources, and behavior problems in children with new-onset seizures. Our major goal was to test whether family adaptive resources moderated the relationship between early temperament dimensions and current behavior problems in 287 children with new-onset seizures.

Magnetic resonance imaging (MRI) and electroencephalographic (EEG) findings in a cohort of normal children with newly diagnosed seizures.

In the initial assessment of children with new-onset seizures, the suggestion that electroencephalography (EEG) should be standard and that magnetic resonance imaging (MRI) should be optional has been questioned. The purposes of this study were to (1) describe the frequency of EEG and MRI abnormalities and (2) explore relationships between MRI and EEG findings to determine their relevance in the assessment of children with new-onset seizures who are otherwise developing normally. As part of an ongoing, prospective study of children with new-onset seizures, we studied 181 children (90 girls and 91 boys).

Overexpression of wild-type creatine transporter (SLC6A8) restores creatine uptake in primary SLC6A8-deficient fibroblasts.

In the study reported, we prove that mutations in the SLC6A8 gene are responsible for SLC6A8 deficiency, a cerebral creatine deficiency syndrome (CCDS), since overexpression of the wild-type SLC6A8 open reading frame (ORF) restores the creatine uptake profile in SLC6A8-deficient fibroblasts.

Comprehensive mutation analysis of GLDC, AMT, and GCSH in nonketotic hyperglycinemia.

Nonketotic hyperglycinemia (NKH) is an inborn error of metabolism characterized by accumulation of glycine in body fluids and various neurological symptoms. NKH is caused by deficiency of the glycine cleavage multi-enzyme system with three specific components encoded by GLDC, AMT, and GCSH. We undertook the first comprehensive screening for GLDC, AMT, and GCSH mutations in 69 families (56, six, and seven families with neonatal, infantile, and late-onset type NKH, respectively).

Stability of salivary concentrations of the newer antiepileptic drugs in the postal system.

Saliva antiepileptic drug (AED) concentrations strongly correlate with serum concentrations. Saliva collection is painless and noninvasive, and untrained personnel can easily be taught the collection process. Remote patients could mail saliva samples to a laboratory for monitoring, and samples could be obtained in the immediate postictal state to provide a "real-time" concentration.

Incidence of brain creatine transporter deficiency in males with developmental delay referred for brain magnetic resonance imaging.

Several case reports describe children with global developmental delay who have brain creatine deficiency, where the deficiency was due to a lack of creatine transport into the brain or altered creatine synthesis. The purpose of this study was to determine what percentage of males with developmental delay referred for brain magnetic resonance imaging (MRI) at the authors' institution in a 12-month period was found to have brain creatine deficiency due to a defect in the creatine transporter gene. In the authors' facility, single voxel proton magnetic resonance spectroscopy (MRS) is routinely performed on any male child age 2 to 18 years with a history of language and/or developmental delay referred for a brain MRI.

Muscle coenzyme Q: a potential test for mitochondrial activity and redox status.

The aim of this study is to determine whether coenzyme Q (CoQ) muscle concentrations and redox state are associated with pathologic changes in muscle biopsy specimens. Skeletal muscle biopsies were collected (January 2002-February 2004) and underwent pathologic evaluation. Quadriceps specimens (n = 47) were stratified accordingly: Group 1, controls without evidence of pathologic abnormalities; Group 2, type I myofiber predominance; Group 3, type II myofiber atrophy; Group 4, lower motor unit disease; and Group 5, muscular dystrophy.

Presence of normal creatine in the muscle of a patient with a mutation in the creatine transporter: a case study.

To date, more than seven families have been reported who carry a mutation in the X-linked creatine-transporter (CrT) gene. The resulting lack of creatine in the brain is associated with mental retardation, severe expressive language disorder, mild epilepsy, and a complete absence of Cr in the brain (measured using MRS). Conversely, these patients had no observable cardiac or musculo-skeletal deficits.

Feasibility and limitations of oxcarbazepine monitoring using salivary monohydroxycarbamazepine (MHD).

The purpose of this study is to determine the feasibility of using 10-hydroxy-10,11-dihydrocarbazepine (MHD) concentration in saliva as an alternative to serum for the therapeutic monitoring of oxcarbazepine (OXC) treatment. Investigators identified subjects seen in neurology clinics at the University of Kentucky Chandler Medical Center. Patients were eligible if they agreed to participate in this study, were taking oxcarbazepine, and if a serum MHD concentration had been ordered by their physician.

High prevalence of SLC6A8 deficiency in X-linked mental retardation.

A novel X-linked mental retardation (XLMR) syndrome was recently identified, resulting from creatine deficiency in the brain caused by mutations in the creatine transporter gene, SLC6A8. We have studied the prevalence of SLC6A8 mutations in a panel of 290 patients with nonsyndromic XLMR archived by the European XLMR Consortium. The full-length open reading frame and splice sites of the SLC6A8 gene were investigated by DNA sequence analysis.