Rare homozygous nonsense variant in AIMP1 causing Early Onset Epileptic Encephalopathy with Burst Suppression (EOEE-BS).

Pathogenic variants in AIMP1 gene are rare causes of neurologic disorders. Homozygous frameshift and nonsense variants in AIMP1 have been described in severe neurodegenerative disease. This is the third report of a homozygous nonsense variant in AIMP1 [c.115 C > T (p.Gln39*)] in a girl with severe neonatal onset epileptic encephalopathy. Like the two other cases reported, our patient is also of Filipino descent. Clinical features include microcephaly, poor visual motor development, shallow breathing, severe hypertonia in extremities, severe global developmental delay, poor gag and suck reflex, failure to thrive in the neonatal period, and early onset intractable seizures. Brain MRI showed hypoplasia of corpus callosum as well as cerebellar vermis, global volume loss and diminished myelination for her age. Electroencephalogram at four months of age showed background consisting of synchronous and asynchronous intervals of burst suppression with intermittent multifocal spikes predominantly in the bi-temporal region, suggestive of Early Onset Epileptic Encephalopathy with Burst Suppression (EOEE-BS) which has not been previously associated with the c.115 C > T variant in AIMP1. Of note, she presented to us in super refractory status epilepticus which was eventually controlled after administration of ketogenic diet and Epidiolex (cannabidiol). This report expands the genetic landscape of EOEE-BS. This is the first case of this specific variant in which Epidiolex was administered, which along with Ketogenic diet aided in controlling patient's super refractory status epilepticus.

Early diagnosis of infantile-onset lysosomal acid lipase deficiency in the advent of available enzyme replacement therapy.

BACKGROUND: Lysosomal acid lipase deficiency (LAL-D) is an autosomal recessive disorder that can present as a severe, infantile form also known as Wolman disease. We sought to determine the outcomes and clinical needs of infants diagnosed with LAL-D, treated with enzyme replacement therapy (ERT). METHODS: A chart review was conducted on two infantile-onset LAL-D patients to determine clinical outcomes based on laboratory results, abdominal imaging, growth and dietary records, cardiology, endocrinology, ophthalmology, hematology, and neurocognitive evaluations. RESULTS: Two patients, both diagnosed and treated before 6 months old, demonstrated clinical improvement following weekly ERT. They required dosage increases to optimize growth and symptomatology. Both received a formula low in long chain triglycerides and high in medium chain triglycerides, an intervention that allowed significant catch-up growth. Patient 1 required treatment for partial adrenal insufficiency and hypothyroidism. Both patients demonstrated reduction in liver and spleen size and varying degrees of improved liver function. Neither experienced serious adverse reactions to ERT. CONCLUSION: ERT has led to longer and healthier survival of affected infants. It is imperative that dietary interventions and systemic clinical care become integral to the management. Continued evidence of survival and clinical improvement in this population, coupled with available mass spectrometry enzyme assay from dried blood spots, raises the question of this rare and possibly underdiagnosed disorder's candidacy for newborn screening.

Diagnostic Yield of Epilepsy Panels in Children With Medication-Refractory Epilepsy.

BACKGROUND: When no chromosomal variations are identified, patients with suspected genetic etiologies can be tested using next-generation sequencing utilizing epilepsy panels. The primary objective of this study was to analyze the diagnostic yield of next-generation sequencing epilepsy panels in medication-resistant epilepsy subjects with non-clinically significant comparative genomic hybridization microarray results. METHODS: We completed a single-center retrospective review of the diagnostic yield of next-generation sequencing epilepsy panels in medication-resistant epilepsy subjects aged 18 years or less who had non-clinically significant comparative genomic hybridization microarray results from January 2011 to December 2014. The primary end point was the yield of clinically significant next-generation sequencing results. RESULTS: Forty-nine subjects (21 male) with medication-refractory epilepsy and clinically in significant comparative genomic hybridization microarray results were identified. Next-generation sequencing abnormalities were seen in 28 subjects (57%): seven of these 28 subjects (25%) had clinically significant findings. Mutations were found in the SCN1A gene in three subjects, in the PCDH19 gene in two subjects, and in DLG3, MECP2, TSC2, and SLC9A6 genes in one subject each. Only the MECP2 mutation was found to be pathogenic in this last subject. The additional yield of next-generation sequencing with uninformative chromosomal microarray was 14%. Positive findings were primarily seen in those with Dravet syndrome, all with SCN1A mutations (42% of clinically significant results). Given the small sample size, a larger prospective study would help to determine the clinical yield of next-generation sequencing. CONCLUSION: Next-generation sequencing seizure panels could be a useful tool in the diagnosis of nonacquired pediatric medication-refractory epilepsy with uninformative comparative genomic hybridization microarray.