Sucheta Joshi

De novo mutations in epileptic encephalopathies

Epileptic encephalopathies are a devastating group of severe childhood epilepsy disorders for which the cause is often unknown. Here we report a screen for de novo mutations in patients with two classical epileptic encephalopathies: infantile spasms (n = 149) and Lennox–Gastaut syndrome (n = 115). We sequenced the exomes of 264 probands, and their parents, and confirmed 329 de novo mutations. A likelihood analysis showed a significant excess of de novo mutations in the ∼4,000 genes that are the most intolerant to functional genetic variation in the human population (P = 2.9 × 10−3). Among these are GABRB3, with de novo mutations in four patients, and ALG13, with the same de novo mutation in two patients; both genes show clear statistical evidence of association with epileptic encephalopathy. Given the relevant site-specific mutation rates, the probabilities of these outcomes occurring by chance are P = 4.1 × 10−10 and P = 7.8 × 10−12, respectively. Other genes with de novo mutations in this cohort include CACNA1A, CHD2, FLNA, GABRA1, GRIN1, GRIN2B, HNRNPU, IQSEC2, MTOR and NEDD4L. Finally, we show that the de novo mutations observed are enriched in specific gene sets including genes regulated by the fragile X protein (P < 10−8), as has been reported previously for autism spectrum disorders.

Ultra-rare genetic variation in common epilepsies: a case-control sequencing study

BACKGROUND Despite progress in understanding the genetics of rare epilepsies, the more common epilepsies have proven less amenable to traditional gene-discovery analyses. We aimed to assess the contribution of ultra-rare genetic variation to common epilepsies. METHODS We did a case-control sequencing study with exome sequence data from unrelated individuals clinically evaluated for one of the two most common epilepsy syndromes: familial genetic generalised epilepsy, or familial or sporadic non-acquired focal epilepsy. Individuals of any age were recruited between Nov 26, 2007, and Aug 2, 2013, through the multicentre Epilepsy Phenome/Genome Project and Epi4K collaborations, and samples were sequenced at the Institute for Genomic Medicine (New York, USA) between Feb 6, 2013, and Aug 18, 2015. To identify epilepsy risk signals, we tested all protein-coding genes for an excess of ultra-rare genetic variation among the cases, compared with control samples with no known epilepsy or epilepsy comorbidity sequenced through unrelated studies. FINDINGS We separately compared the sequence data from 640 individuals with familial genetic generalised epilepsy and 525 individuals with familial non-acquired focal epilepsy to the same group of 3877 controls, and found significantly higher rates of ultra-rare deleterious variation in genes established as causative for dominant epilepsy disorders (familial genetic generalised epilepsy: odd ratio [OR] 2·3, 95% CI 1·7-3·2, p=9·1 × 10-8; familial non-acquired focal epilepsy 3·6, 2·7-4·9, p=1·1 × 10-17). Comparison of an additional cohort of 662 individuals with sporadic non-acquired focal epilepsy to controls did not identify study-wide significant signals. For the individuals with familial non-acquired focal epilepsy, we found that five known epilepsy genes ranked as the top five genes enriched for ultra-rare deleterious variation. After accounting for the control carrier rate, we estimate that these five genes contribute to the risk of epilepsy in approximately 8% of individuals with familial non-acquired focal epilepsy. Our analyses showed that no individual gene was significantly associated with familial genetic generalised epilepsy; however, known epilepsy genes had lower p values relative to the rest of the protein-coding genes (p=5·8 × 10-8) that were lower than expected from a random sampling of genes. INTERPRETATION We identified excess ultra-rare variation in known epilepsy genes, which establishes a clear connection between the genetics of common and rare, severe epilepsies, and shows that the variants responsible for epilepsy risk are exceptionally rare in the general population. Our results suggest that the emerging paradigm of targeting of treatments to the genetic cause in rare devastating epilepsies might also extend to a proportion of common epilepsies. These findings might allow clinicians to broadly explain the cause of these syndromes to patients, and lay the foundation for possible precision treatments in the future. FUNDING National Institute of Neurological Disorders and Stroke (NINDS), and Epilepsy Research UK.

Response To Treatment In A Prospective National Infantile Spasms Cohort.

Infantile spasms are seizures associated with a severe epileptic encephalopathy presenting in the first 2 years of life, and optimal treatment continues to be debated. This study evaluates early and sustained response to initial treatments and addresses both clinical remission and electrographic resolution of hypsarrhythmia. Secondarily, it assesses whether response to treatment differs by etiology or developmental status.

Vitamin D and Bone Health Among Children With Epilepsy

The lay media and scientific literature have focused increasing attention on vitamin D deficiency and insufficiency in recent years. Low vitamin D levels confer increased an risk of abnormal bone mineralization, and are linked to poor bone health in epilepsy patients. However, vitamin D is not the only determinant of bone health in children with epilepsy. Anticonvulsant medications, in addition to features and comorbidities of epilepsy and coexisting neurologic diseases, are important factors in this complex topic. We review the basic metabolism of vitamin D in terms of bone health among children with epilepsy. We also discuss the literature regarding vitamin D and bone mineral density in this population. Finally, we suggest algorithms for screening and treating vitamin D insufficiency in these patients.

The current evaluation and treatment of infantile spasms among members of the child neurology society

The optimal evaluation and treatment of children with infantile spasms is unknown. To aid in the development of a standardized approach to infantile spasms, members of the Child Neurology Society were surveyed to determine common practice. The survey had 222 responders with a responder rate of 18.5%. We found that the diagnostic evaluation and the use of first-line treatments varied among responders. For example, although adrenocorticotropic hormone continues to be the most commonly used first-line treatment for infantile spasms not due to tuberous sclerosis, some clinicians use corticosteroids, vigabatrin, and topiramate as first-line treatments for this group. Seventy percent of our responders reported seeing fewer than 10 new-onset cases of infantile spasms per year. Thus, future clinical trials will require multicenter collaboration. An important first step in such collaboration is to standardize the evaluation and treatment of infantile spasms within and between participating centers.

Prevalence and risk factors for vitamin D insufficiency among children with epilepsy

This cross-sectional study was designed to determine the prevalence of, and risk factors for, vitamin D insufficiency among children treated for epilepsy in a general pediatric neurology clinic. Included were 78 children with epilepsy, aged 3-17 years, treated by the authors between September 2008 and March 2009. Vitamin D levels and relevant risk factors were evaluated using multiple logistic regression. Of the 78 children, 41% were male and 81% were of European origin; the mean age was 11.64 + or - 4.37 years. 25-hydroxyvitamin D levels of <20 ng/mL were observed in 25% of the children and levels considered to be normal (>32 ng/mL) were observed in only 25%. Girls and children with elevated body mass index were at increased risk for low 25-hydroxyvitamin D. The odds ratio for low 25-hydroxyvitamin D was 4.07 for girls versus boys, with a 95% confidence interval of 1.18-13.97; for each 1-unit increase in body mass index, the odds ratio was 1.179, with a 95% confidence interval of 1.047-1.329. Use of newer antiepileptic drugs was not associated with altered risk, compared with older enzyme-inducing drugs. Vitamin D insufficiency was highly prevalent in this unselected population of children with epilepsy. Female sex and increased body mass index were significant risk factors for low vitamin D levels, but antiepileptic drug regimen was not.

Copy number variant analysis from exome data in 349 patients with epileptic encephalopathy

Infantile spasms (IS) and Lennox–Gastaut syndrome (LGS) are epileptic encephalopathies characterized by early onset, intractable seizures, and poor developmental outcomes. De novo sequence mutations and copy number variants (CNVs) are causative in a subset of cases. We used exome sequence data in 349 trios with IS or LGS to identify putative de novo CNVs. We confirm 18 de novo CNVs in 17 patients (4.8%), 10 of which are likely pathogenic, giving a firm genetic diagnosis for 2.9% of patients. Confirmation of exome‐predicted CNVs by array‐based methods is still required due to false‐positive rates of prediction algorithms. Our exome‐based results are consistent with recent array‐based studies in similar cohorts and highlight novel candidate genes for IS and LGS. Ann Neurol 2015;78:323–328

Treatment adherence among adolescents with epilepsy: What really matters?

Treatment adherence is often suboptimal among adolescents with epilepsy. However, knowledge is lacking regarding factors that affect adherence. Empirical studies and theories of human development suggest that self-management skills, self-efficacy, and sense of control are related to adherence. Eighty-eight adolescents with epilepsy, and their parents, completed standardized measures assessing epilepsy knowledge and expectations, treatment self-management, sense of control, and self-efficacy. Better self-reported parent adherence was correlated with greater epilepsy knowledge/expectations (p<0.001) and more medications (p = 0.042). Better self-reported adolescent adherence was correlated with fewer siblings (p = 0.003) and higher adolescent epilepsy knowledge/expectations (p<0.001). Greater adolescent epilepsy knowledge/expectations correlated with parent self-reported adherence (p<0.001), Powerful others locus of control (p = 0.008), and adolescent/parent discordance regarding epilepsy knowledge/expectations (p<0.001). Interventions that enhance adolescents knowledge of epilepsy and their treatment plan, while ensuring that teens and parents are in agreement with regard to epilepsy treatment, might contribute to better adherence.

Response to second treatment after initial failed treatment in a multicenter prospective infantile spasms cohort

Infantile spasms (IS) represent a severe epileptic encephalopathy presenting in the first 2 years of life. Recommended first‐line therapies (hormonal therapy or vigabatrin) often fail. We evaluated response to second treatment for IS in children in whom the initial therapy failed to produce both clinical remission and electrographic resolution of hypsarhythmia and whether time to treatment was related to outcome.

Knowledge of Epilepsy and Preferred Sources of Information Among Elementary School Teachers

We conducted an online survey of elementary school teachers in Washtenaw County, Michigan, regarding their confidence in their knowledge of epilepsy and their preferred media or sources of information about epilepsy. Eighty-three teachers (9.3%) responded. One quarter expressed a lack of confidence in their ability to teach students with epilepsy or to respond appropriately to a seizure. Teachers most frequently (68%) cited the Internet as their primary source of information about epilepsy, with the school nurse and parents/guardians also frequently mentioned (55% and 48%, respectively). In contrast, most respondents prefer that their information come from the school nurse (74%) or a physician (73%), while only 25% cited the Internet as a preferred source. Teachers most frequently indicated EpilepsyFoundation.org (70.5%) as a trusted source of information. Future collaborative education efforts between school nurses and physicians, especially through use of the Internet, could improve teachers’ knowledge of epilepsy.