Identification of two mutations in cis in the SCN1A gene in a family showing genetic epilepsy with febrile seizures plus (GEFS+) and idiopathic generalized epilepsy (IGE).

Mutations in the SCN1A gene causing either loss or gain of function have been frequently found in patients affected by genetic epilepsy with febrile seizures plus (GEFS+) or Dravet syndrome (also named severe myoclonic epilepsy in infancy SMEI). By mutation screening of the SCN1A gene, we identified for the first time a case of two missense mutations in cis (p.[Arg1525Gln;Thr297Ile]) in all affected individuals of an Italian family showing GEFS+ and idiopathic generalized epilepsy (IGE). The p.Arg1525Gln mutation was not previously reported yet and was predicted to be pathological by prediction tools, whereas the p.Thr297Ile was already identified in patients showing SMEI. Functional studies revealed that the Nav1.1 channels harboring both mutations were characterized by a significant shift in the activation curve towards more positive potentials. Our data demonstrate that the p.Arg1525Gln represents a novel mutation in the SCN1A gene altering the channel properties in the co-presence of the p.Thr297Ile.

Adverse Effects and Surgical Complications in Pediatric Patients Undergoing Vagal Nerve Stimulation for Drug-Resistant Epilepsy.

Vagal nerve stimulation (VNS) is an effective treatment for drug-resistant epilepsy that is not suitable for resective surgery, both in adults and in children. Few reports describe the adverse effects and complications of VNS. The aim of our study was to present a series of 33 pediatric patients who underwent VNS for drug-resistant epilepsy and to discuss the adverse effects and complications through a review of the literature.The adverse effects of VNS are usually transient and are dependent on stimulation of the vagus and its efferent fibers; surgical complications of the procedure may be challenging and patients sometimes require further surgery; generally these complications affect VNS efficacy; in addition, hardware complications also have to be taken into account.In our experience and according to the literature, adverse effects and surgical and hardware complications are uncommon and can usually be managed definitely. Careful selection of patients, particularly from a respiratory and cardiac point of view, has to be done before surgery to limit the incidence of some adverse effects.

Epilepsia partialis continua and generalized nonconvulsive status epilepticus during the course of argininemia: a report on two cases.

Argininemia is a rare inherited disorder of the urea cycle because of a deficiency of the enzyme arginase I causing an increase of arginine and guanidino compounds in the blood, urine, and cerebrospinal fluid. The clinical picture is characterized by a mild cognitive dysfunction, progressive asymmetrical paraparesis, and seizures. Here, we describe two cases of argininemia where either epilepsia partialis continua (EPC) or nonconvulsive status epilepticus (NCSE) were the presenting manifestations of epilepsy. This is the first report of EPC in an urea cycle disorder. In both the cases, status epilepticus resolved with anticonvulsive drugs. EPC was successfully treated with levetiracetam, and NCSE with valproic acid. No side effects were observed. Because hyperammonemia and NCSE may have the same features of stupor, a neurophysiological approach might prove useful in differentiating these two conditions. Overall, our results strongly indicate that a correct NCSE diagnosis is mandatory to prevent further deterioration in these patients.

Epilepsy and argininosuccinic aciduria.

BACKGROUND: We have reviewed the occurrence of epilepsy in our patients with argininosuccinic aciduria (ASA) (OMIM 207900) and the possible relationship of late epilepsy to symptomatic seizures in the neonatal period, hyperammonaemia and treatments. METHODS: We retrospectively analysed 11 ASA patients (8 neonatal onset and 3 late onset), 6 of whom had developed epilepsy. RESULTS: Epilepsy in our sample was frequent (55 %). It developed after a seizure-free period from the onset of the metabolic disease and seizures were responsive to treatment in all cases. Arginine plasma levels were kept in the same range for the 2 groups of patients with and without epilepsy. CONCLUSIONS: Although epilepsy is reported to be common among patients with ASA, very few long-term follow-up studies are available. The pathophysiological mechanism of epileptogenesis remains unclear. Neither hyperammonaemia nor acute symptomatic seizures at birth seem to be predictive of late epilepsy. Excessive arginine dosages as a cause of epilepsy could be reasonably excluded since our 3 late onset patients developed epilepsy before the diagnosis of ASA, at a time when they were likely to be arginine deficient. Arginine deficiency may not be excluded as cause of epilepsy, but further studies are needed to define its role.

Influenza A (H1N1) encephalitis with severe intracranial hypertension.

The swine-origin influenza A (H1N1) virus was responsible for the pandemic infection in 2009. We report a case of encephalitis diagnosed as the H1N1 virus infection in a young child. The H1N1 virus infection can be causative of the encephalitis, as with other influenza virus infections. For patients presenting with influenza-like illness accompanied by mental status changes or seizures, high suspicion for unusual presentations of influenza A virus infection and careful monitoring, including EEG and intracranial pressure monitoring, are essential for reducing complications.

Early-onset benign occipital seizure susceptibility syndrome.

PURPOSE: Childhood epilepsy with occipital paroxysms (CEOP) is characterised by ictal visual hallucinations and occipital epileptiform activity on interictal EEG. A variant has been described with nonvisual symptoms including tonic head and eye deviation, vomiting, and episodes of partial status epilepticus. We fully documented the electroclinical features of such patients to determine whether classification separate from CEOP is justified. METHODS: This was a multicentre study with participating investigators submitting details of patients with idiopathic occipital seizures characterised by ictal head or eye deviation and vomiting. RESULTS: One hundred thirteen patients were recruited. Seizures began in early childhood (mean, 4.6 years) and occurred infrequently (mean total seizures, 3); 30% of patients had only a single seizure. Two thirds of seizures were nocturnal. Ictal eye deviation occurred in 79%, vomiting in 70%, and head deviation in 35%. Seizures were predominantly complex partial in type. Partial status epilepticus occurred in 44% of patients. Seventy-four percent of patients had occipital interictal EEG epileptiform activity, predominantly right sided, with fixation-off sensitivity. Extraoccipital EEG abnormalities occurred in 35% of patients. Prognosis was excellent: the mean duration of active seizures was 1 year. CONCLUSIONS: Although the two groups shared identical EEG features, the distinct clinical symptoms probably justify separate classification. Early-onset benign occipital seizure syndrome (EBOSS) is suggested as an appropriate name for the variant group.

[EEG anomalies in the prodromic phase of Rasmussen's syndrome. Report of two cases]. / Anomalies EEG dans la phase prémonitoire du syndrome de Rasmussen. A propos de deux observations.

Electroencephalographic (EEG) recordings were studied at disease onset in two subjects presenting with Rasmussen's syndrome. Particular attention was paid to abnormalities detected during the prodromic phase before clinical outcome suggested the existence of chronic encephalitis. EEG recordings showed focal, polymorphic abnormalities associated with slow biphasic complexes (SBC). These complexes that are composed of two slow waves with opposite polarity, a 150- to 250-mV peak-to-peak amplitude and a 500-ms duration have only been described in inflammatory syndromes of the central nervous system. Their occurrence at onset of Rasmussen's syndrome are discussed.