Follow-up study of idiopathic generalized epilepsy with associated absence seizure and myoclonic epilepsy of infancy.

We evaluated the long-term prognosis of patients featuring the association of absences and myoclonic epilepsy of infancy. Our cohort consisted of 10 male subjects with mean age at seizure onset of 29 months. Follow-up data included seizure outcome and EEG findings. All individuals received antiepileptic drugs (AEDs) as monotherapy (6 patients) or polytherapy (4 patients) for a mean period of 24 months. Over a 30-60 month evaluation period (mean: 43 months), all patients were seizure-free. Follow-up data after withdrawal of antiepileptic therapy were obtained for a mean period of 22 months. None of the children did develop other age-related epileptic syndrome after AEDs discontinuation. Furthermore, follow-up EEG data after drugs withdrawal were normal and none of the patients showed cognitive impairment. In conclusion, we confirm that absence seizures may occur in association with myoclonic epilepsy of infancy. This condition shows excellent prognosis with either favourable neurologic development and seizure outcome in these children.

A novel AMT gene mutation in a newborn with nonketotic hyperglycinemia and early myoclonic encephalopathy.

Early myoclonic encephalopathy (EME) presents in neonatal period with erratic or fragmentary myoclonus and a burst-suppression electroencephalography (EEG) pattern. Nonketotic hyperglycinemia (NKH) is the most common metabolic cause of EME and genetic testing confirms the diagnosis of NKH in around 75% of the patients with a clinical diagnosis of NKH. Three genes are known to cause NKH. Here we describe a case of EME caused by NKH in which a new mutation in aminomethyltransferase (AMT) gene has been detected.