Case Series of Early SCN1A-Related Developmental and Epileptic Encephalopathies.

Introduction: The developmental and epileptic encephalopathies (DEEs) are a heterogeneous group of rare neurodevelopmental disorders, characterized by early onset seizures that are often intractable, electroencephalographic abnormalities, developmental delay, or regression. The SCN1A pathogenic variants can present as DEE. They are characterized by early infantile seizure onset, profound intellectual disability, and a severe hyperkinetic movement disorder. Studies are lacking, hence we are reporting a case series of early SCN1A-related DEE. The objective of the study was to report clinical and molecular aspects of early SCN1A-related DEE. Materials and Methods: A retrospective chart review of children with DEEs secondary to SCN1A pathogenic variants from January 2015 to March 2020 in a tertiary care referral center from south India. Results: Out of eleven children, seven were boys. The mean age of presentation was 3.5 months. Nine children had seizures triggered by fever. All the children presented with focal and generalized seizures along with epileptic spasms. No focal neurological deficits were noted; routine testing, neuroimaging, and metabolic tests were normal in all the cases. In all the cases, hypsarrhythmia was noted on electroencephalogram (EEG). All the children had pathogenic variants in the SCN1A gene. Five children responded to steroids, one child responded to vigabatrin, and one child responded to stiripentol, but all of them had relapsed and were refractory to other antiepileptic drugs. At follow-up, all children had developmental delays and six of them had autistic features. Conclusion: Early SCN1A-related encephalopathies should be considered in the differential diagnosis of early infantile epileptic encephalopathies. Identification of this condition is important, as treatment and outcome are different from other epileptic encephalopathies.

Spectrum of Nonepileptic Paroxysmal Events in Children from Southern India.

Background Nonepileptic paroxysmal events (NEPEs) present with episodes similar to epileptic seizures but without abnormal electrical discharge on electroencephalogram (EEG). NEPEs are commonly misdiagnosed as epilepsy. Epilepsy is diagnosed on the basis of a detailed history and examination. Emphasis during history to rule out the possibility of NEPE is important. The wrong diagnosis of epilepsy can lead to physical, psychological, and financial harm to the child and the family. Hence, this study was planned. Objective The objective of the study is to evaluate clinical profile, frequency, and spectrum of NEPE in children. Materials and Methods This is a prospective observational study. Patients with NEPE between January 2014 and August 2016 aged < 18 years were enrolled. NEPEs were diagnosed on the basis of history, home video, and EEG recordings. Patients were divided into different categories according to age, specific type of disorder, and system responsible. Patients were followed for their NEPE frequency and outcome. Results A total of 3,660 children presented with paroxysmal events; of them 8% were diagnosed with NEPE. Patients diagnosed with NEPE were classified into three age groups on the basis of their age of onset of symptom; of the total 285 patients, there were 2 neonates (0.7%), 160 infants (56%), and 123 children and adolescents (43.1%). Fifty-eight percent patients were boys. The most common diagnoses were breath-holding spells 113 (39%), followed by syncope 38 (13.3%) and psychogenic nonepileptic seizures 37 (12.9%). About 9 and 5% of patients had concomitant epilepsy and developmental delay, respectively. Conclusions NEPEs account for 8% of paroxysmal events. Most common NEPEs were breath-holding spells among infants and syncope and "psychogenic nonepileptic seizures" in children and adolescents.

Sandhoff Disease without Hepatosplenomegaly Due to Hexosaminidase B Gene Mutation.

Sandhoff disease is a neurodegenerative disease caused due to deficiency of hexosaminidase (HEX) A and B. A 1-year-old male child presented with regression of milestones, exaggerated startle response, decreased vision, and seizures from 6 months of age. The child had coarse facies without hepatosplenomegaly. Serum levels of ß hexosaminidase total (A + B) were low. Genetic testing for Sandhoff disease revealed a homozygous missense variant on HEXB gene. The case is presented to highlight that the absence of hepatosplenomegaly should not restrain in suspecting Sandhoff disease.

Atypical rabies encephalitis in a six-year-old boy: clinical, radiological, and laboratory findings.

A 6-year-old boy from India developed an atypical form of rabies following a stray dog bite and as a consequence of not receiving the standard World Health Organization recommended post-exposure prophylaxis for category III wounds. Serial rising rabies virus neutralizing antibody titres in serum and cerebrospinal fluid by rapid fluorescent focus inhibition test helped confirm the diagnosis of rabies. The child has survived for 4 months since the onset of illness, albeit with neurological sequelae.