Paola Iannetti

Calcium-channel Blocker Verapamil Administration in Prolonged and Refractory Status Epilepticus

Summary:  We report on an 11‐year healthy boy who presented refractory status epilepticus (SE), which was unresponsive to conventional antiepileptic drugs used in the algorithm of the treatment of SE. Based on evidence that verapamil has anticonvulsant activity in animal models and the fact that the boy had a supraventricular tachycardia (140–160 b/min), i.v. verapamil (0.034 mg/min) was administered on day 37, and after a 3.125 mg cumulative verapamil dose (1.5 hour after initiation of the infusion), the patient regained consciousness was able to breathe spontaneously and the electrical SE promptly disappeared. The apparent dramatic response to i.v. verapamil may be explained by its direct anticonvulsant action on the basis of the potential involvement of calcium channels in epileptic activity and that verapamil, a known Pgp inhibitor in the cerebrovascular endothelium in the epilepticus focus, acted by facilitating the brain penetration of the antiepileptic drugs that our patient was receiving simultaneously.

Neuronal migration disorders: clinical, neuroradiologic and genetics aspects.

Disorders of neuronal migration are a heterogeneous group of disorders of nervous system development.

Multiple sclerosis in children under 10 years of age.

Abstract.Despite the consistent amount of information accumulated in recent years on multiple sclerosis (MS) in childhood, many clinicians still view this condition as an exclusively young adult-onset disease and do not consider that it may occur and manifest even during infancy and pre-school age, suggesting that the number of MS cases in the paediatric age group may have been underestimated. Thus, the need to have practical parameters for therapeutic, counselling and educational purposes in such settings as caring for patients whose onset of disease is at very early ages may increasingly arise for practising clinicians. In addition, the clinical and radiographic criteria for the diagnosis of MS have not been validated in a paediatric MS population; accordingly, inclusion age at onset (such as for research purposes) is generally over 10 years. To highlight the peculiarities that characterise MS when it begins at this young age we have reviewed the literature and summarised our preliminary results with the national registry of the Italian Society of Paediatric Neurology (SINP) Study Group on Childhood MS in the group of MS patients with the earliest onset of disease (i. e., <10 years of age).

Addition of verapamil in the treatment of severe myoclonic epilepsy in infancy

We report on the use of the voltage-gated calcium channel blocker (Vg-CCB), verapamil, as an add-on anticonvulsant medication in two girls, 4 and 14 years of age, who were affected by severe myoclonic epilepsy in infancy (SMEI) or Dravet syndrome, a channelopathy caused by abnormalities in the voltage-gated sodium channel neuronal type alpha1 subunit (SCN1A) gene at 2q24. Both girls had pharmacoresistant epilepsy and developmental delay. Mutation analysis for the SCN1A gene revealed a missense mutation in exon 2 in the 4-year-old girl. Verapamil was co-administered in both children with a prompt response in controlling status epilepticus, myoclonic jerks, and partial and generalized seizures. The therapeutic effect lasted 13 months in the 14-year-old girl, while it is still present after a 20-month follow-up period in the 4-year-old girl who, in addition, has experienced improvement in motor and language development. The verapamil vVg-CCB, which crosses the blood-brain barrier (BBB): (a) inhibits the P-glycoprotein, an active efflux transporter protein expressed in normal tissue, including the brain, which is believed to contribute to the in situ phenomenon of multidrug resistance; and (b) may regulate membrane depolarization induced by abnormal sodium channels functions by modulating the abnormal Ca++ influxes into neurons with subsequent cell resting. This is the first report on long-lasting verapamil therapy in SMEI. The functional consequences of such in vivo modulating effects on Ca++ channels could contribute to rational targeting for future molecular therapeutic approaches in pharmacoresistant epileptic channelopathies.

Efficacy and safety of levetiracetam: An add-on trial in children with refractory epilepsy

The aim of this multicentric, prospective and uncontrolled study was to evaluate the efficacy and safety of levetiracetam in 110 children with refractory epilepsy, of whom 21 were less than 4 years old. After a median follow-up period of 7 months, levetiracetam administration was effective (responders with >50% decrease in seizure frequency) in 39% of children, of whom 10 (9%) became seizure-free. The efficacy was higher in patients with localization-related epilepsy (58% of responders) than in those with generalized epilepsy (37% of responders). Levetiracetam was well tolerated. The main side effects of somnolence and irritability occurred in 14% of patients. In one patient acute choreoathetosis occurred after few doses of levetiracetam. Overall, the adverse effects were not severe. Children younger than 4 years were particularly tolerant. In conclusion, the present study confirms that levetiracetam is effective and well tolerated as an add-on treatment in children with refractory epilepsy. Our preliminary data also indicate that levetiracetam may be a valid therapeutic option for epilepsy in infants and young children.

Visual Field Constriction in Children With Epilepsy on Vigabatrin Treatment

Vigabatrin is considered the drug of choice for infantile spasms and simple and complex partial epilepsy in childhood. Its mechanism of action relies on the irreversible inhibition of γ-aminobutyric acid (GABA) transaminase. Since June 1997 several articles have been published reporting visual field constriction in adult patients on vigabatrin therapy. Recently, 7 pediatric patients, 1 on vigabatrin monotherapy and 6 on add-on therapy with visual field constriction have been described. We have observed 30 pediatric patients with epilepsy (14 boys and 16 girls), ages ranging from 4 to 20 years (mean: 11 years and 2 months) treated with vigabatrin for infantile spasms, simple and complex partial epilepsy, who had never complained of ophthalmologic disturbances. Twenty-one patients underwent complete routine ophthalmologic examination (fundus oculi, visual acuity, intraocular pressure, and visual field tests); 9 children (<6 years old) underwent only fundus examination, because collaboration was lacking. We report on 4 children showing constriction of visual field, prevailing in nasal hemifield. In 1 child, visual abnormalities were stable even 10 months after vigabatrin discontinuation, while in another a greater improvement was observed 5 months after discontinuation. The possible mechanisms have been discussed and the cone dysfunction, connected with GABA augmentation in the outer retina, has been outlined. We suggest a possible protocol to control visual abnormalities in epileptic children.

Levetiracetam in juvenile myoclonic epilepsy: long‐term efficacy in newly diagnosed adolescents

The aim of this study was to evaluate the efficacy and tolerability of levetiracetam (LEV) monotherapy in juvenile myoclonic epilepsy (JME). The study group consisted of 32 patients with epilepsy (20 males, 12 females) with a mean age of 13 years 3 months (SD 7y 11mo) at seizure onset. LEV was administered as the first drug; all patients were followed up at 6 and 12 months. The dose that achieved seizure control ranged from 1000 to 2500mg/daily. At 6‐month evaluation: 15 patients were seizure free; 14 patients were responders (>50% reduction in seizures); and three patients had marginal effects (<50% reduction of seizures). At 12‐month evaluation: 29 patients were seizure free; three patients were responders. No patients reported adverse events. These data provide preliminary evidence that LEV may be effective for treating patients with newly diagnosed JME.

Paroxysmal Tonic Upgaze: Physiopathological Considerations in Three Additional Cases

Paroxysmal tonic upgaze of childhood has been described as a benign distinctive syndrome of abnormal ocular movement, with or without concomitant ataxia. After the first observation of four children, a further 29 patients have been reported with a wide spectrum of neurologic abnormalities such as ataxia, unsteady of gait, learning disabilities and mental retardation at follow-up. Electroencephalograms were normal in all the subjects and magnetic resonance imaging showed deficient myelination in only one patient. Recently it has been suggested that paroxysmal tonic upgaze could be a heterogeneous syndrome, ranging from a simply age-dependent manifestation to a clinical appearance of a variety of disorders affecting the corticomesencephalic loop of vertical eye movement. Moreover, it also could be an early sign of more widespread neurologic dysfunction. We describe three patients who presented paroxysmal tonic upgaze; in one, ataxia was present; in the second child, ataxia and language disorder also were observed; and in the third patient paroxysmal tonic upgaze was associated with loss of muscle tone (drop-attack-like events). On magnetic resonance imaging, a pinealoma compressing the dorsal mesencephalic region was detected. On the basis of our observations, we suggest that any insult with periaqueductal mesencephalic gray-matter involvement could be considered the basic condition for this peculiar clinical manifestation. (J Child Neurol 2000;15:15-18).

Efficacy and safety of topiramate in refractory epilepsy of childhood : Long-term follow-up study

This study aimed to evaluate the long-term efficacy and safety of topiramate in treating children with drug-resistant epilepsy. A multicentric, retrospective, open-label, add-on study was undertaken of 277 children (mean age 8.4 years; range 12 months to 16 years) affected by drug-resistant epilepsy. The efficacy was rated according to the seizure types and epilepsy syndrome. After a mean period of 27.5 months of treatment (range 24—61 months), 11 patients (4%) were seizure free and 56 (20%) had more than 50% reduction in seizure frequency. The efficacy of topiramate treatment was noted in localization-related epilepsy and in generalized epilepsy. In addition, in a group of 114 patients, we compared the initial efficacy (evaluated after a mean of 9 months of follow-up) and the retention at a mean of 30 months of topiramate with regard to loss of efficacy (defined as the return to the baseline seizure frequency). Fifty-five (48%) of 114 patients were initial responders. The retention at a mean of 30 months was 23 of 114 patients (20%), 4 of whom (3.5%) were still seizure free. A loss of efficacy occurred in 32 of the 55 initial responders (58%). It was prominent in patients with generalized epilepsy, such as symptomatic infantile spasms and Lennox-Gastaut syndrome, as well as in those with Dravet syndrome. By contrast, a well-sustained topiramate efficacy was noted among patients with localization-related epilepsy. Globally, adverse events were observed in 161 patients (58%) and were mainly represented by weight loss, hyperthermia, sedation, and nervousness, which, in most cases, disappeared after slowing titration or reducing the dosage of the drug. In conclusion, the present long-term study confirms that topiramate represents a useful drug effective in a wide range of seizures and epilepsy syndromes. Moreover, preliminary data seem to suggest that the efficacy of topiramate, when evaluated in the long-term perspective, is more sustained in localization-related epilepsy than in generalized epilepsy. (J Child Neurol 2005;20:893—897).

Ophthalmological manifestations in segmental neurofibromatosis type 1

Aims: To study the ophthalmological manifestations in individuals with the typical features of neurofibromatosis type 1 (NF1) circumscribed to one or more body segments, usually referred to as segmental NF1. Methods: Visual acuity and colour tests, visual field examination, slit lamp biomicroscopy of the anterior segment, and a detailed examination of the retina by indirect ophthalmoscopy were performed at diagnosis and follow up in 72 consecutive subjects (29 males, 43 females; aged 1–64 years; mean age 14.6 years) seen at the university departments of paediatrics in Catania and Rome, Italy, during years 1990–2003, who had in restricted body areas: (1) typical pigmentary manifestations of NF1 (café au lait spots and freckling) only (n = 48); (2) NF1 pigmentary manifestations and neurofibromas alone (n = 2); (3) neurofibromas only (n = 15); and (4) plexiform neurofibromas only (n = 7). Results: None of the 72 patients had Lisch nodules in the iris irrespective of age at eye examination or hypertelorism (a “minor” NF1 feature) and none developed typical associated ophthalmological NF1 complications. An additional child had an isolated optic pathways glioma (OPG), which behaved both biologically and radiographically as an NF1 associated OPG. Conclusions: This represents the first systematic study reporting on eye involvement in the largest series of individuals at different ages having segmental NF1. As one of the postulated mechanisms to explain segmental NF1 is somatic mosaicism for the NF1 gene (so far demonstrated only in two patients) the present findings could be explained either by the fact that the eye is too far from the mutated area with NF1 lesions in most cases or by the NF1 (or other “predisposing” or “cooperating”) gene mutation restricted to too few cellular clones or to tissues embryologically different from the eye.