Childhood Epilepsy: an Update on Diagnosis and Management

American Journal of Neuroscience Review Childhood Epilepsy: An Update on Diagnosis and Management Khaled Saad Department of Pediatrics, Faculty of Medicine, University of Assiut, Assiut 71516, Egypt Article history Abstract: Within the past few years there is a rapid expansion in our Received: 23-10-2014 understanding of epilepsy. The development of new anti-epileptic drugs and Revised: 25-11-2014 refinements to epilepsy surgery are widening the therapeutic options for Accepted: 12-01-2015 epilepsy. In addition, the classification of the epilepsies continues to evolve based on an increased understanding of the molecular genetics of the condition and this includes the recognition of possible novel epilepsy syndromes. This review considers some of these exciting developments, as well as addressing the essential features of the diagnosis, investigations, management and impact of epilepsy in childhood. Keywords: Children, Epilepsy, Seizure, Anti-Epileptic Drugs Introduction guidelines for optimal practices, rational therapy and counseling (Aylwad, 2008; Tamber and Mountz, 2012; Epilepsy is a common heterogeneous neurological Sharma, 2013). problem in children. It exerts a significant physical, psychological, economic and social toll on children and Definitions their caregivers. Fifty million people have epilepsies A seizure is defined as an excessive burst of abnormal globally; more than half of them are children. In the synchronized neuronal activity affecting small or large USA; between 25,000 and 40,000 children will have a neuronal networks that results in clinical manifestations first non-febrile seizure each year. The problem is that are sudden, transient and usually brief. Epilepsy is further compounded in developing countries as they add defined as a disorder of the brain characterized by any of about 75-80% of new cases of epilepsy (Guerrini, 2006; the following conditions: (1) At least two unprovoked (or Tamber and Mountz, 2012; Sharma, 2013). The seizures reflex) seizures occurring >24 h apart, (2) One and epilepsies in children are extremely diverse, unprovoked (or reflex) seizure and a probability of further differing markedly in age of onset, seizure seizures similar to the general recurrence risk (at least characteristics, associated comorbidities, treatment and 60%) after two unprovoked seizures, occurring over the prognosis. Given that there is a shortage of pediatric next 10 years and 3) Diagnosis of an epilepsy syndrome epileptologists practicing around the world, it is (Hauser and Banerjee, 2008; Tamber and Mountz, 2012; impossible for all children with recurrent seizures to Fisher et al., 2014). Provoked seizure is a seizure that receive their care from subspecialists. Rather, such occurs in reaction to an acute, transient condition children often need to rely on pediatric neurologists, affecting the brain. Provoking factors include, but are not general pediatricians and/or family practitioners limited to, head trauma, stroke, intracranial infections, provide the care they need and deserve. Without a firm acute metabolic disruptions (e.g., hypoglycemia, anoxia) understanding of the complexities of childhood epilepsy, it may be not possible for such physicians to and acute drug or toxin poisoning (Hauser and Banerjee, always make an accurate diagnosis and plan an 2008; Tamber and Mountz, 2012). effective treatment strategy. So it is important for the Incidence general pediatrician to be aware of the evaluation and management of these patients (Tamber and Mountz, Epileptic seizures affect 1-2 % of the population and 2012; Sharma, 2013). Also, pediatricians and 4% of children. Developing countries have higher practitioners should have a role in preventing epilepsy by prevalence due to the poorer perinatal care and standards minimizing neurological insults in early infancy and of nutrition and public hygiene and the greater risk of childhood. In addition, there is a need to focus on brain injury, cerebral infection or other symptomatic primary health care providers by providing them cerebral conditions. Incidence of seizures is age © 2014 The Khaled Saad. This open access article is distributed under a Creative Commons Attribution (CC-BY) 3.0 license. Khaled Saad / American Journal of Neuroscience 2014, 5 (2): 36.51 DOI: 10.3844/amjnsp.2014.36.51 dependent. The highest incidence rate (100 per 100,000) defect(s) in which seizures are the core symptom of the is observed in the first year of life, declining to disorder. This attribution must be supported by specific approximately 20 cases per 100,000 per year in forms of evidence. The knowledge regarding the adolescence. Childhood epilepsy has a prevalence of genetic contributions may derive from specific approximately 0.5-0.8% and comprises a heterogeneous molecular genetic studies that have been well replicated group of disorders, including a variety of epilepsy and even become the basis of diagnostic tests (e.g., syndromes that range in severity from benign to SCN1A and Dravet syndrome) or the evidence for a progressive and catastrophic. Focal epilepsies predominate central role of a genetic component may come from (59-63%) than generalized epilepsy (12-29%). In about appropriately designed family studies. 20% classification may change on follow up (Hauser and Structural/Metabolic Banerjee, 2008; Sharma, 2013; Cross et al., 2013). There is a distinct other structural or metabolic ILAE Classifications of Seizures, Epilepsy condition or disease that has been demonstrated to be The ILAE Commission on Classification and associated with an increased risk of developing epilepsy. Terminology released a revision of the previous Structural lesions include acquired disorders such as system in 2010 (Berg et al., 2010). The report is not a stroke, trauma and infection. They may also be of new classification, but it organizes the current genetic origin (e.g., Tuberous sclerosis). knowledge (Table 1). Unknown Mode of Seizure Onset The nature of the underlying cause is as yet In the 2010 ILAE proposal, the mode of seizure unknown; it may have a genetic basis (e.g., A previously onset is divided into three basic groups based upon unrecognized channelopathy) or it may be the result of clinical and EEG data: Focal, generalized and unknown an unrecognized structural or metabolic disorder. (e.g., Epileptic spasms) (Berg et al., 2010): Epilepsies of unknown cause are those, which in the past were termed ‘‘cryptogenic’’. Generalized epileptic seizures are conceptualized as those that originating at some point within and Types of Seizures rapidly engaging, bilaterally distributed networks, Generalized Seizures which can be subcortical or cortical structures, but do not essentially, include the entire cortex. In Generalized seizures are seizures that rapidly addition, generalized seizures can be asymmetric engaging, bilaterally distributed networks, which can be (Berg et al., 2010; Berg and Scheffer, 2011) subcortical or cortical structures and in which The term focal has replaced partial epileptic consciousness is impaired from the onset. The seizures, which are conceptualized as originating previously used terminology of seizure classification, within one hemisphere. They may be localized or “secondary generalized” and “secondarily generalized,” widely distributed. Focal seizures may originate are no longer recognized in the ILAE classification, the in subcortical structures. No natural classification term changed to “focal seizure evolving to a bilateral, for focal seizures exists; focal seizures should be convulsive seizure. Generalized seizures are described according to their manifestations (e.g., subdivided into multiple types (Table 1) (Browne and dyscognitive, focal motor) (Berg et al., 2010; Holmes, 2008; Berg et al., 2010; Mikati, 2011; Berg and Scheffer, 2011) Tamber and Mountz, 2012; Piña-Garza and Fenichel, 2013; Rudzinski et al., 2013): Underlying Type of Cause (Etiology) Absence Seizures The terms idiopathic, symptomatic and Absence seizures are generalized seizures, cryptogenic, are now not used. Instead of the previous indicating bihemispheric involvement, clinically and on terms the following three terms (genetic, the EEG. Absence Seizures are characterized by a structural/metabolic and unknown) and their sudden onset behavioral arrest, a blank stare, associated concepts are recommended (Berg et al., unresponsiveness and sometimes a brief upward 2010; Berg and Scheffer, 2011): rotation of the eyes. The duration is typically a few Genetic seconds to half a minute. There is little to no postictal confusion and the patient typically resumes the activity The concept of genetic epilepsy is that the epilepsy is he/she was doing prior to the seizures. This seizure type the direct result of a known or presumed genetic is also referred to as simple typical absence. 37 Khaled Saad / American Journal of Neuroscience 2014, 5 (2): 36.51 DOI: 10.3844/amjnsp.2014.36.51 Table 1. ILAE classification of seizures* (Berg et al., 2010) consciousness and postictal confusion. The ictal EEG I. Generalized seizures pattern is characterized by brief generalized polyspikes 1. Tonic-clonic [in any combination]. or polyspikes and wave discharges which corresponds to 2. Absence: the myoclonic jerk (Tamber and Mountz, 2012; a. Typical. Rudzinski et al., 2013). b. Atypical. c. Absence with special features: Clonic Seizures Myoclonic absence. Eyelid myoclonia. Clonic Seizures are typically seen in neonates and 3. Myoclonic: young children. They are characterized by repetitive a. Myoclonic. rhythmic

Load more