Global Perspectives

Epilepsy is common in the pediatric population and can significantly affect the health and quality of life of the child and family. It is estimated that 0.5% to 1% of children have epilepsy1. As in the majority of epilepsy syndromes onset occurs during infancy or childhood, it becomes a challenging task of diagnosing, classifying, and managing epilepsy in the pediatric population. About 25% of children who are diagnosed with epilepsy remain refractory to traditional therapy in spite of the development of an improved classification system as well as recent advances in pharmacologic therapy. Hence the management of epilepsy in paediatric patients requires careful evaluation, appropriate classification and pharmacologic therapy. Lack of firm data outlining the appropriate use of new antiepileptic drugs (AEDs) in the pediatric population also limits the use of these agents in children.

Advances in the diagnosis and management of pediatric seizure disorders in the twentieth century

Several advances have been made in the past century in understanding and management of paediatric seizure disorders. These advances have been reviewed by Camfield P and Campfield C who and have discussed various aspects of diagnosis and treatment of pediatric seizures2.

Electroencephalography (EEG) has been used as a tool for assessing brain disorders since 1929. EEG has been improved with better amplifiers and filters. Video-EEG allows simultaneous analysis of the clinical and electrical event for better classification of seizures with localization of seizure onset when surgery is contemplated. But authors state that EEG has significant limits as it is observed that some children without seizures have “epileptiform” EEG whereas others with severe epilepsy have normal interictal EEG findings. All the same this test continues to supplement the clinical history and aids in diagnosis2.

Computed tomography and magnetic resonance imaging scanning have revolutionized our understanding of the cause of epilepsy for many children, especially those with partial epilepsies. Currently brain imaging is included in the assessment of most children with newly diagnosed epilepsy. A specific diagnosis from imaging is critical to treatment.

The development of antiepileptic drugs opened new avenues for the management of childhood epilepsies. Phenobarbital became the first satisfactory treatment for epilepsy. Bromides had been discovered earlier, but they were toxic and their spectrum of action did not rival the remarkable efficacy of phenobarbital. Phenobarbital has recently fallen from favor because of cognitive side effects, although some of the newer agents, particularly topiramate, probably have serious adverse effects on learning. Phenytoin was then introduced in the early 1940s. Carbamazepine was discovered in a search for better antipsychotic medications. Valproic acid remains the most effective drug for many childhood epilepsies despite some significant side effects such as frequent weight gain and very rare liver failure or pancreatitis. Since gamma-aminobutyric acid had emerged as the major cortical inhibitory neurotransmitter, drugs that looked like GABA were sought. Gabapentin was synthesized as a GABA analogue; it has anti-seizure properties but apparently not through the GABA system. Tiagabine blocks GABA reuptake and vigabatrin prevents its degradation by blocking GABA transaminase2.

Surgery is found to be helpful in a small number of children. There are continual advances in the patient selection technique, operative technique which result in improved results with surgery. Brain imaging, particularly magnetic resonance imaging, allows much better selection of surgical candidates and guides the surgical resection2.

The understanding of the biochemical mechanism for some inherited epilepsies is one of the most exciting advance in the past decade. Benign familial neonatal convulsions - an autosomal dominant disorder was shown to result from a defect in membrane potassium channels. These neonatal seizures are eventually outgrown. Nocturnal dominant frontal lobe epilepsy is also dominantly inherited and caused by a defect in the acetylcholine receptor. Generalized Epilepsy with Febrile Seizures Plus is a more complex clinical disorder with febrile seizures that persist beyond 5 years of age that are followed by generalized epilepsy in adolescence. This disorder appears to result from a defect in the sodium channel2.

The authors concluded that with the emerging advances in the evaluation and management of childhood epilepsy, the stage is now clear for a more rationalized approach in the management of epileptic seizures in children2.