Diagnostic Yield of Epilepsy-Genes Sequencing and Chromosomal Microarray in Pediatric Epilepsy

Genetic Epilepsies With Onset in Infancy and Toddlerhood: A Prospective Single-Center Study in India

BACKGROUND

The burden of genetic causes of epilepsy is higher in infants and toddlers. Early diagnosis helps in precision therapy and prenatal diagnosis. The spectrum of genetic causes can vary depending on the location and prevalence of consanguinity practices.

METHODS

Children having epilepsy with onset before age three years were enrolled after ruling out acquired causes. Neuroimaging, electroencephalography, and whole exome sequencing (WES) were done and seizure outcome was assessed after six months.

RESULTS

We enrolled 147 participants (82 boys, 65 girls). Mean age at seizure onset was 5.5 ± 6.5 months. WES gave an overall yield of 61.9% (91/147) and 71.4% (40/56) in cases with epilepsy onset before three months. Seventy (76.7%) cases had developmental delay. Commonly implicated genes were SCN1A, KCNQ2, ALDH7A1, STXBP1, TBC1D24, CDKL5, CPLX1, BRAT1, WWOX, and RHOBTB2. The common comorbidities of autism, attention-deficit/hyperactivity disorder, and intellectual disability had a significant association with genetic epilepsy. WES helped in precision medicine in over 40% of cases. While normal development was associated with higher rates of seizure freedom, those with severe microcephaly, a seizure burden of >200/month, or rigidity had higher mortality rates.

CONCLUSIONS

Genetic etiology for epilepsy is common in children with seizure onset below age three years, with yield being the highest for onset in the first three months. Presence of comorbidities increased the yield of genetic diagnosis. Autosomal recessive disorders are more common in India due to higher consanguinity rates. Higher seizure burden, severe microcephaly, or infantile epileptic spasm syndrome are associated with higher mortality.

Examining Impact of Insurance Type on Genetic Testing in Pediatric Neurology

BACKGROUND

Studies that examine the impact of insurance type on the ease of obtaining genetic testing are scarce. Therefore, we aim to analyze how different types of insurance influence the time taken to obtain genetic test results among pediatric neurology patients.

METHODS

This was a retrospective cohort study from Dayton Children's Hospital. Patients who had at least one neurological genetic result found in the electronic medical record from January 1, 2014, to March 1, 2023, were included in the study. Variables collected include demographics, health insurance data, and genetic testing results.

RESULTS

A total of 141 patients were included. Most patients were male (51.8%), white (78.0%), and not Hispanic/Latino (96.5%). The mean age at the time of genetic testing was 7.9 years. Most patients had Medicaid as their primary insurance (60.3%) when compared with private insurance (39.7%). Two hundred fifteen genetic reports were examined (137 Medicaid charts and 78 private insurance charts). There was no statistically significant difference from mean time lapse between test order date and results date for Medicaid patients (27.3 days) versus private insurance (31.5 days, P = 0.40). Molecular genetics testing and epilepsy gene panel order were the most common tests ordered for both Medicaid (86.1%, 37.2%) and private insurance (88.5%, 39.7%, respectively).

CONCLUSIONS

The mean time between test order date and results date was comparable between private- and Medicaid-insured patients. Our results suggest that there is no significant difference for time to result between pediatric neurology patients who carry public versus private insurance for genetic testing.

Genetic Epilepsies and Developmental Epileptic Encephalopathies with Early Onset: A Multicenter Study

The genetic causes of epilepsies and developmental and epileptic encephalopathies (DEE) with onset in early childhood are increasingly recognized. Their outcomes vary from benign to severe disability. In this paper, we wished to retrospectively review the clinical, genetic, EEG, neuroimaging, and outcome data of patients experiencing the onset of epilepsy in the first three years of life, diagnosed and followed up in four Italian epilepsy centres (Epilepsy Centre of San Paolo University Hospital in Milan, Child Neurology and Psychiatry Unit of AUSL-IRCCS di Reggio Emilia, Pediatric Neurology Unit of Vittore Buzzi Children's Hospital, Milan, and Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, Pavia). We included 168 patients (104 with monogenic conditions, 45 with copy number variations (CNVs) or chromosomal abnormalities, and 19 with variants of unknown significance), who had been followed up for a mean of 14.75 years. We found a high occurrence of generalized seizures at onset, drug resistance, abnormal neurological examination, global developmental delay and intellectual disability, and behavioural and psychiatric comorbidities. We also documented differing presentations between monogenic issues versus CNVs and chromosomal conditions, as well as atypical/rare phenotypes. Genetic early-childhood-onset epilepsies and DEE show a very wide phenotypic and genotypic spectrum, with a high risk of complex neurological and neuropsychiatric phenotypes.