Effect of vigabatrin on seizure control and safety profile in different subgroups of children with epilepsy

Risk Assessment of Psychotropic Drugs on Mitochondrial Function Using In Vitro Assays

Mitochondria are potential targets responsible for some drug- and xenobiotic-induced organ toxicities. However, molecular mechanisms of drug-induced mitochondrial toxicities are mostly unknown. Here, multiple in vitro assays were used to investigate the effects of 22 psychotropic drugs on mitochondrial function. The acute extracellular flux assay identified inhibitors of the electron transport chain (ETC), i.e., aripiprazole, phenytoin, and fluoxetine, an uncoupler (reserpine), substrate inhibitors (quetiapine, carbamazepine, buspirone, and tianeptine), and cytotoxic compounds (chlorpromazine and valproic acid) in HepG2 cells. Using permeabilized HepG2 cells revealed minimum effective concentrations of 66.3, 6730, 44.5, and 72.1 µM for the inhibition of complex-I-linked respiration for quetiapine, valproic acid, buspirone, and fluoxetine, respectively. Assessing complex-II-linked respiration in isolated rat liver mitochondria revealed haloperidol is an ETC inhibitor, chlorpromazine is an uncoupler in basal respiration and an ETC inhibitor under uncoupled respiration (IC50 = 135 µM), while olanzapine causes a mild dissipation of the membrane potential at 50 µM. This research elucidates some mechanisms of drug toxicity and provides some insight into their safety profile for clinical drug decisions.

Anticonvulsant Classes and Possible Mechanism of Actions

Epilepsy is considered one of the most common neurological disorders worldwide; it needs long-term or life-long treatment. Despite the presence of several novel antiepileptic drugs, approximately 30% patients still suffer from drug-resistant epilepsy. Subsequently, searching for new anticonvulsants with lower toxicity and better efficacy is still in paramount demand. Using target-based studies in the discovery of novel antiepileptics is uncommon owing to the insufficient information on the molecular pathway of epilepsy and complex mode of action for most of known antiepileptic drugs. In this review, we investigated the properties of anticonvulsants, types of epileptic seizures, and mechanism of action for anticonvulsants.

Utilizing Infantile Spasm Seizure Activity as a Baseline Vital in the Setting of Acute Pseudomonas aeruginosa Pneumonia

The objective of this case report is to describe and document a decrease in seizure activity in a 16-year-old female with a past medical history of Aicardi syndrome (AS) and infantile spasms (IS) while being treated for acute Pseudomonas aeruginosa pneumonia with pleural effusion. This patient presented to the pediatric emergency department with a chief complaint of fever, tachycardia, increased nasal secretions, and oxygen requirement at home. She was admitted to the general pediatric medical floor for treatment of an adenovirus infection due to her having a complex medical history and her being medically unstable. On hospital admission day 1, she developed post-viral P. aeruginosa pneumonia. She subsequently had three days of complete clinical seizure cessation without changing her anti-epileptic medications. It was not until the symptomatology related to her pneumonia improved that her seizure activity returned to its baseline frequency. The treating team discovered that the decrease in her frequency of seizure activity related to periods of increased physiologic stress was not new. Her mother reported that she has used the relationship between her daughter's seizures and any acute illness to gauge how her daughter was "feeling" medically. Three weeks prior to this hospital admission, her mother reported that her daughter's seizures ceased for two days during a period in which it was determined that the patient was having renal colic and passed a renal stone. This phenomenon, the decrease in the frequency of seizure activity related to periods of increased physiologic stress, could help primary caretakers assess when significant, new comorbid conditions are present and could aid in the primary assessment of physical health in a particular patient population who are unable to verbalize their current medical status. Utilizing seizure activity as an at-home vital sign could help caretakers recognize when their patient is under an elevated physiologic stress condition. Recognizing the relationship between seizure frequency and acute illness could also help diagnostically, as ISs are difficult to both diagnose and manage. Also, future research on this possible association could explore more understanding of IS and pathophysiology of such phenomenon.

Pharmacologic and Dietary Treatments for Epilepsies in Children Aged 1-36 Months: A Systematic Review

BACKGROUND AND OBJECTIVES

Early life epilepsies are common and often debilitating, but no evidence-based management guidelines exist outside of those for infantile spasms. We conducted a systematic review of the effectiveness and harms of pharmacologic and dietary treatments for epilepsy in children aged 1-36 months without infantile spasms.

METHODS

We searched EMBASE, MEDLINE, PubMed, and the Cochrane Library for studies published from January 1, 1999, to August 19, 2021. Using prespecified criteria, we identified studies reporting data on children aged 1-36 months receiving pharmacologic or dietary treatments for epilepsy. We did not require that studies report etiology-specific data. We excluded studies of neonates, infantile spasms, and status epilepticus. We included studies administering 1 of 29 pharmacologic treatments and/or 1 of 5 dietary treatments reporting effectiveness outcomes at ≥ 12 weeks. We reviewed the full text to find any subgroup analyses of children aged 1-36 months.

RESULTS

Twenty-three studies met inclusion criteria (6 randomized studies, 2 nonrandomized comparative studies, and 15 prestudies/poststudies). All conclusions were rated low strength of evidence. Levetiracetam leads to seizure freedom in some infants (32% and 66% in studies reporting seizure freedom), but data on 6 other medications were insufficient to permit conclusions about effectiveness (topiramate, lamotrigine, phenytoin, vigabatrin, rufinamide, and stiripentol). Three medications (levetiracetam, topiramate, and lamotrigine) were rarely discontinued because of adverse effects, and severe events were rare. For diets, the ketogenic diet leads to seizure freedom in some infants (rates 12%-37%), and both the ketogenic diet and modified Atkins diet reduce average seizure frequency, but reductions are greater with the ketogenic diet (1 RCT reported a 71% frequency reduction at 6 months for ketogenic diet vs only a 28% reduction for the modified Atkins diet). Dietary harms were not well-reported.

DISCUSSION

Little high-quality evidence exists on pharmacologic and dietary treatments for early life epilepsies. Future research should isolate how treatments contribute to outcomes, conduct etiology-specific analyses, and report patient-centered outcomes such as hospitalization, neurodevelopment, functional performance, sleep quality, and patient and caregiver quality of life.

TRIAL REGISTRATION INFORMATION

This systematic review was registered in PROSPERO (CRD42021220352) on March 5, 2021.

Treatment of Epilepsy Associated with Common Chromosomal Developmental Diseases

Chromosomal diseases are heterogeneous conditions with complex phenotypes, which include also epileptic seizures. Each chromosomal syndrome has a range of specific characteristics regarding the type of seizures, EEG findings and specific response to antiepileptic drugs, significant in the context of the respective genetic etiology. Therefore, it is very important to know these particularities, in order to avoid an exacerbation of seizures or some side effects. In this paper we will present a review of the epileptic seizures and antiepileptic treatment in some of the most common chromosomal syndromes.

Update on Drug Management of Refractory Epilepsy in Tuberous Sclerosis Complex

Tuberous sclerosis complex (TSC) is a genetic neurocutaneous disorder with epilepsy as a common and early presenting symptom. The neurological phenotype, however, is variable and unpredictable. Early and refractory seizures, infantile spasms in particular, are associated with a poor neurological outcome. Preliminary data suggests early and aggressive seizure control may mitigate the detrimental neurodevelopmental effects of epilepsy. For infantile spasms, vigabatrin is the first line of treatment, and steroids and classic antiepileptic drugs (AEDs) are suitable for second line. Based on retrospective data, vigabatrin should be considered for other indications, especially in infants with focal seizures, as this may prevent infantile spasms, but also in children and adults with epileptic spasms and tonic seizures. Otherwise, for most seizure types, treatment is similar to that for patients without TSC, including the use of novel AEDs, although limited data are available. Three major developments are changing the field of epilepsy management in TSC. First, final recommendations on preventive treatment with vigabatrin will result from two multicenter trials in the US (PREVeNT, clinicaltrials.gov #NCT02849457) and Europe (EPISTOP, clinicaltrials.gov #NCT02098759). Second, treatment with everolimus, an inhibitor of the mechanistic target of rapamycin (mTOR), reduced seizures when compared to placebo. Further, mTOR inhibitors may have an overall disease-modifying effect. Third, the role of cannabidiol in the treatment of refractory seizures in TSC is yet to be established. With treatment recommendations in TSC, we keep an eye on the prize for the broader field of pediatric epilepsy: the lessons learned from TSC are likely applicable to other epileptic encephalopathies.

Epileptic spasms as the presenting seizure type in a patient with a new "O" of TORCH, congenital Zika virus infection

Congenital TORCH infections are a significant cause of epileptic spasms, an infantile epileptic encephalopathy, through disruptions to several pathways in neurodevelopment. Congenital Zika virus has a similar neurotropism to other TORCH agents, and leads to microcephaly, severe neurodevelopmental impairment, and high rates of early onset seizures. Here we report a child with confirmed congenital Zika virus who developed extensor epileptic spasms and hypsarrhythmia associated with a loss of early developmental milestones. Early treatment led to resolution of epileptic spasms and improved developmental trajectory, though the child continues to have ongoing focal seizures and prominent developmental impairment. Congenital Zika virus infection requires close monitoring as early identification of epileptic spasms is likely important in long term developmental outcome.

Pharmacokinetics and Drug Interaction of Antiepileptic Drugs in Children and Adolescents

Selecting the most appropriate antiepileptic drug (AED) or combination of drugs for each patient and identifying the most suitable therapeutic regimen for their needs is increasingly challenging, especially among pediatric populations. In fact, the pharmacokinetics of several drugs vary widely in children with epilepsy because of age-related factors, which can influence the absorption, distribution, metabolism, and elimination of the pharmacological agent. In addition, individual factors, such as seizure type, associated comorbidities, individual pharmacokinetics, and potential drug interactions, may contribute to large fluctuations in serum drug concentrations and, therefore, clinical response. Therapeutic drug concentration monitoring (TDM) is an essential tool to deal with this complexity, enabling the definition of individual therapeutic concentrations and adaptive control of dosing to minimize drug interactions and prevent loss of efficacy or toxicity. Moreover, pharmacokinetic/pharmacodynamic modelling integrated with dashboard systems have recently been tested in antiepileptic therapy, although more clinical trials are required to support their use in clinical practice. We review the mechanism of action, pharmacokinetics, drug-drug interactions, and safety/tolerability profiles of the main AEDs currently used in children and adolescents, paying particular regard to issues of relevance when treating this patient population. Indications for TDM are provided for each AED as useful support to the clinical management of pediatric patients with epilepsy by optimizing pharmacological therapy.

Safety and tolerability profile of new antiepileptic drug treatment in children with epilepsy

INTRODUCTION

Treatment of pediatric epilepsy requires a careful evaluation of the safety and tolerability profile of antiepileptic drugs (AEDs) to avoid or minimize as much as possible adverse events (AEs) on various organs, hematological parameters, and growth, pubertal, motor, cognitive and behavioral development.

AREAS COVERED

Treatment-emergent AEs (TEAEs) reported in the literature 2000-2018 regarding second- and third-generation AEDs used in the pediatric age, with exclusion of the neonatal period that exhibits specific peculiarities, have been described on the basis of their frequency, severity/tolerability, and particular association with a given AED.

EXPERT OPINION

Somnolence/sedation and behavioral changes, like irritability and nervousness, are among the most commonly observed TEAEs associated with almost all AEDs. Lamotrigine, Gabapentin, Oxcarbazepine, and Levetiracetam appear to be the best-tolerated AEDs with a ≤2% withdrawal rate, while Tiagabine and Everolimus are discontinued in up to >20% of the patients because of intolerable TEAEs. For some AEDs, literature data are scanty to draw a high-level evidence on their safety and tolerability profile. The reasons are: insufficient population size, short duration of treatments, or lack of controlled trials. A future goal is that of identifying clearer, easier, and more homogeneous methodological strategies to facilitate AED testing in pediatric populations.

Cognitive and Behavioral Comorbidities: An Unwanted Effect of Antiepileptic Drugs in Children

Epilepsy is one of the most common neurological disorders and, despite optimally chosen and dosed antiepileptic drugs (AEDs), approximately 20%-30% of patients will continue to have seizures. Behavior and cognition are negatively impacted by seizures, but AEDs are also a major contributor to behavioral and cognitive deficits. However, the cognitive and behavioral effect of AEDs in children is insufficiently emphasized in the literature. This review summarizes the cognitive and behavioral effects of AEDs in the pediatric population with the objective of helping pediatricians and pediatric neurologists to select the AEDs with the best profile for their individual patient's needs.