Two cases of early-onset myoclonic seizures with continuous parietal delta activity caused by EEF1A2 mutations.

BACKGROUND: Mutations in the elongation factor 1 alpha 2 (EEF1A2) gene have recently been shown to cause severe intellectual disability with early-onset epilepsy. The specific manifestations of mutations in this gene remain unknown. CASE REPORT: We report two cases of severe intellectual disability accompanied by early-onset epilepsy with continuous delta activity evident on electroencephalography. Both cases presented with developmental delay and repetitive myoclonic seizures in early infancy. Both cases showed continuous high-voltage delta activity over both parietal areas when awake, as revealed by interictal electroencephalograms. After the emergence of continuous delta activity, development stagnated. One case showed some development after relief of the seizures and epileptic activity, but drug resistant seizures recurred, and the development again became stagnant. In both cases, a de novo recurrent heterozygous mutation in EEF1A2 [c.364G>A (p.E122K)] was identified by whole-exome sequencing. CONCLUSION: This report provides clinical data on epileptic encephalopathy in patients with EEF1A2 mutation. Continuous high-voltage delta activity seen over both parietal areas may be a unique manifestation of EEF1A2 mutation. Epileptic activity may aggravate the effect of the mutation on brain development.

A case of Guillain-Barré syndrome with meningeal irritation.

Here, we report a 5-year-old girl with Guillain-Barré syndrome who presented with a chief complaint of pain in the extremities, which was followed by neck stiffness. Bladder dysfunction was found, which required catheterization. Magnetic resonance imaging revealed marked enhancement of the nerve roots in the cauda equina on T1-weighted imaging after gadolinium injection, and nerve conduction studies led to a diagnosis of Guillain-Barré syndrome. Her symptoms improved after intravenous immunoglobulin therapy, but her neck stiffness remained 16 days after admission. Four weeks after admission, she could walk without support. As patients with signs of meningeal irritation may be diagnosed with other diseases, such as meningitis, it is important to recognize atypical cases of pediatric Guillain-Barré syndrome to achieve early diagnosis and treatment.

Evaluation of Binding Equation Method for Unbound Serum Concentration Prediction of Valproic Acid in Polytherapy Pediatric Patients with Epilepsy.

In a previous study, we determined the in vivo population binding parameters of valproic acid (VPA) to serum proteins at single dose in nine healthy young and defined a binding equation that was derived from the Scatchard equation. Schever et al. and Yu also determined the in vivo population binding parameters of VPA in patients with epilepsy receiving VPA monotherapy or polytherapy. In this study, we retrospectively evaluated the ability of a binding equation using each of population mean binding parameters of Kodama et al. (Method 1), Scheyer et al. (Method 2), or Yu (Method 3) to predict the unbound serum VPA concentration in 23 pediatric patients with epilepsy receiving polytherapy. Mean prediction error, mean absolute prediction error (MAE), and root mean squared error (RMSE) were separately calculated for each method and served as a measure of prediction bias and precision. All three methods were significantly biased, showing a bias to overpredict unbound serum VPA. The MAEs and RMSEs for Methods 1 and 2 were similar in magnitude (Method 1: MAE = 16.5, RMSE = 23.1; Method 2: MAE = 14.0, RMSE = 17.5). On the other hand, each value for Method 3 was extremely high (MAE = 32.8 and RMSE = 36.3). Method 3 is apparently inferior to other two methods in accuracy and precision. For Methods 1 and 2, similar tendency to overprediction was observed in total concentration above 400 &mgr;mol L(minus sign1). These two methods may be useful to patients with total VPA lower than 400 &mgr;mol L(minus sign1).