Characteristics of Acute Nystagmus in the Pediatric Emergency Department.

OBJECTIVES: Acute nystagmus (AN) is an uncommon neurologic sign in children presenting to pediatric emergency departments. We described the epidemiology, clinical features, and underlying causes of AN in a large cohort of children, aiming at identifying features associated with higher risk of severe underlying urgent conditions (UCs). METHODS: Clinical records of all patients aged 0 to 18 years presenting for AN to the pediatric emergency departments of 9 Italian hospitals in an 8-year period were retrospectively reviewed. Clinical and demographic features and the underlying causes were analyzed. A logistic regression model was applied to detect predictive variables associated with a higher risk of UCs. RESULTS: A total of 206 patients with AN were included (male-to-female ratio: 1.01; mean age: 8 years 11 months). The most frequently associated symptoms were headache (43.2%) and vertigo (42.2%). Ataxia (17.5%) and strabismus (13.1%) were the most common neurologic signs. Migraine (25.7%) and vestibular disorders (14.1%) were the most common causes of AN. Idiopathic infantile nystagmus was the most common cause in infants <1 year of age. UCs accounted for 18.9% of all cases, mostly represented by brain tumors (8.3%). Accordant with the logistic model, cranial nerve deficits, ataxia, or strabismus were strongly associated with an underlying UC. Presence of vertigo or attribution of a nonurgent triage code was associated with a reduced risk of UCs. CONCLUSIONS: AN should be considered an alarming finding in children given the risk of severe UCs. Cranial nerve palsy, ataxia, and strabismus should be considered red flags during the assessment of a child with AN.

Unusual association of SCN2A epileptic encephalopathy with severe cortical dysplasia detected by prenatal MRI.

We present an atypical association of SCN2A epileptic encephalopathy with severe cortical dysplasia. SCN2A mutations are associated with epileptic syndromes from benign to extremely severe in absence of such macroscopic brain findings. Prenatal MRI (Magnetic Resonance Imaging) in a 32 weeks fetus, with US (Ultrasonography) diagnosis of isolated ventriculomegaly showed CNS (Central Nervous System) dysplasia characterized by lack of differentiation between cortical and subcortical layers, pachygyria and corpus callosum dysgenesis. Postnatal MRI confirmed the prenatal findings. On day 6 the baby presented a focal status epilepticus, partially controlled by phenobarbital, phenytoin, and levetiracetam. After three weeks a moderate improvement in seizure control has been achieved with carbamazepine. Exome sequencing detected a de novo heterozygous mutation in the SCN2A gene, encoding the αII-subunit of a sodium channel. The patient findings expand the phenotype spectrum of SCN2A mutations to epileptic encephalopathies with macroscopic brain developmental features.