Osmotic Demyelination Syndrome in Children.

Osmotic demyelination syndrome is an acute demyelination process that usually occurs several days following an osmotic stress. This syndrome is rare in adults (0.4% to 0.56%) and even more uncommon in children. We performed a review of all reported pediatric osmotic demyelination syndrome patients from 1960 to 2018. Among all 106 cases, 49 presented with isolated central pontine myelinolysis, 30 with isolated extrapontine myelinolysis, and 27 with combined central pontine myelinolysis and extrapontine myelinolysis. There was no gender preponderance, and the highest prevalence was noted between the ages one and five years. Magnetic resonance imaging remains the diagnostic modality of choice, and diffusion tensor imaging is now increasingly used for prognostication in osmotic demyelination syndrome. Sixty percent of the children had a complete neurological recovery. Current management of osmotic demyelination syndrome in children consists of supportive medical care, steroids, and intravenous immunoglobulin. Our review of the literature supports the hypothesis that steroids and immunoglobulins are potentially helpful, although additional controlled studies are needed.

Therapeutic Effect of Steroids in Osmotic Demyelination of Infancy.

An 11-month-old male presented with acute gastroenteritis, seizures, and altered mental status. Laboratory workup revealed serum sodium of 177 mmol/L. Magnetic resonance imaging of the brain showed reduced diffusion in the supratentorial white matter, T2 hyperintensities in the left central pons and midbrain, subacute stroke in the right occipital lobe, and bilateral cerebellar hemorrhagic infarcts. The child was presumed to have hypernatremia-induced central pontine and extrapontine myelinolysis. He received 5 days of high-dose methylprednisolone for persistent encephalopathy and spastic quadriparesis with rapid recovery of his cognitive function and neurological examination. The child remained seizure-free and achieved normal development at 3-month and 2-year follow-ups. Osmotic demyelination of infancy may leave children with a significant neurological deficit. For favorable neurological outcome, early steroids should be considered.

Subclinical Rhythmic EEG Discharge of Adult (SREDA) in a Child With Generalized Epilepsy and Literature Review of SREDA in Children.

Subclinical rhythmic discharges of adult (SREDA) is a rare benign EEG variant in adults and is of unknown clinical significance. Its occurrence in children is extremely rare. In review of the literature, it has been described in only four children. We present a case of a 10-year-old female with generalized idiopathic childhood absence epilepsy who is noted to have SREDA in three subsequent EEGs performed across a 25-month span. She had no clinical change with these discharges and it was believed to be a benign variant. Including our patient, three of four children with SREDA presented with generalized epilepsy leading to the conclusion that, although rare, SREDA is more common in children presenting with generalized epilepsy.

Late-onset radiation-induced vasculopathy and stroke in a child with medulloblastoma.

We report a case of a 15-year-old boy who presented to our institution with left-sided weakness and slurred speech. He had a history of medulloblastoma diagnosed at 3 years of age, status postsurgical resection and craniospinal radiation. Magnetic resonance imaging (MRI) of brain revealed a right paramedian pontine infarction, suspected secondary to late-onset radiation-induced vasculopathy of the vertebrobasilar system. Radiation to the brain is associated with increased incidence of ischemic stroke. Clinicians should have a high index of suspicion for stroke when these patients present with new neurologic symptoms.