You are in: eMedicine Specialties > Neurology > Pediatric Neurology First Seizure: Pediatric PerspectiveArticle Last Updated: Jun 20, 2008AUTHOR AND EDITOR INFORMATIONSection 1 of 12
  Author: Catherine J Chu-Shore, MD, Assistant in Neurology, Massachusetts General Hospital Catherine J Chu-Shore is a member of the following medical societies: American Academy of Neurology, American Academy of Pediatrics, Child Neurology Society, and Massachusetts Medical Society Coauthor(s): S Matthew Stead, MD, PhD, Assistant Professor of Neurology, Mayo Clinic College of Medicine; Consulting Staff, Division of Child and Adolescent Neurology, Department of Neurology, Mayo Clinic; Brian S Tseng, MD, PhD, Assistant Professor, Department of Neurology, Division of Pediatric Neurology, Harvard Medical School, Massachusetts General Hospital Editors: Ann M Neumeyer, MD, Clinic Director, Instructor, Departments of Neurology and Pediatrics, Massachusetts General Hospital, Harvard Medical School; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Kenneth J Mack, MD, PhD, Senior Associate Consultant, Department of Child and Adolescent Neurology, Mayo Clinic; Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital; Amy Kao, MD, Assistant Professor, Department of Neurology, Department of Pediatrics, Division of Pediatrics, Oregon Health and Science University; Consulting Staff, Shriners Hospital Author and Editor Disclosure Synonyms and related keywords: epilepsy, febrile seizure, childhood seizure, infantile spasm, petit mal epilepsy, benign rolandic epilepsy, juvenile myoclonic epilepsy, JME, meningitis, encephalitis, absence epilepsy, complex partial seizures BACKGROUNDSection 2 of 12
  The incidence of first unprovoked seizures in children younger than age 15 is estimated to be 124 per 100,000 person-years.1 Many children who experience a first seizure may never experience a second seizure. However, a seizure may be the initial presentation of a more serious medical condition. Epilepsy is a condition in which a child has 2 or more seizures without a proximal cause for the seizures. When evaluating a child who has experienced a first seizure, the clinician needs to address the following:
DIFFERENTIAL DIAGNOSISSection 3 of 12
Many disorders can mimic seizures in children and should be considered in the differential diagnosis of first seizure in a child. The most common nonepileptic paroxysmal disorders include the following:2
POTENTIAL ETIOLOGIESSection 4 of 12
Identification of the underlying seizure etiology helps identify potential treatment alternatives and the prognosis for that child. Some common childhood seizures are observed in the following situations:
Most children with a first afebrile seizure do not have a clear underlying etiology. In children who develop recurrent seizures, most are ultimately diagnosed with idiopathic or cryptogenic epilepsy.4
For more information regarding specific pediatric epilepsy syndromes, please refer to the International League Against Epilepsy. CLINICALSection 5 of 12
History Because medical personnel often do not witness the first seizure, the medical history becomes the most important part of the evaluation. Ask the person who has witnessed the seizure to describe the event from its start to finish, as this is helpful in the evaluation of the seizure. In the history, a description (eg, the patient was staring with his eyes up and to the right) is more useful than a label (eg, the patient had a petit mal seizure). An accurate description of seizure semiology is important because different anticonvulsant medications are indicated and contraindicated for specific seizure types. Physical
LABORATORY AND DIAGNOSTIC EVALUATIONSection 6 of 12
Initial laboratory evaluation of a first seizure can include serum studies for glucose, electrolytes, calcium, and magnesium and toxicology studies. The American Academy of Neurology (AAN) recommends that clinicians use their clinical judgment. Perform a CT scan if the patient has had a recent head trauma, significantly altered mental status, a significant headache, papilledema, or a bulging fontanelle. Consider a lumbar puncture (LP) in patients who have fever and a stiff neck or who have fever and are unconscious. If increased intracranial pressure is suspected, obtain noncontrast head CT prior to LP, as there may be a risk of inducing cerebral herniation with space-occupying lesions or obstructive hydrocephalus. The AAN recommends lumbar puncture be performed in any child younger than 6 months with persistent changes in mental status or any child with meningeal signs.5 If suspicion of CNS infection is high, appropriate empiric antibiotic and antiviral medications should begin promptly. Steroids are currently thought to improve outcome in some forms of CNS bacterial infection, in particular Haemophilus influenzae type b infection, and should be given before the antibiotics as a rapid infusion unless this would delay the initiation of antibiotic therapy. LP is best obtained prior to antibiotic administration, but LP can be obtained during or after, if technical factors would introduce a substantial treatment delay. Give particular attention to the laboratory evaluation of the neonate. Frequently, glucose and calcium abnormalities can be observed in the first week of life. When a metabolic abnormality is suspected in the neonate, also evaluate serum ammonia, serum lactate and pyruvate, serum for amino acids, and urine for organic acids. Ammonia levels greater than 200 µmol/L in neonates or 100 µmol/L in older patients are very suggestive of metabolic disease warranting emergent workup and treatment. ROLE OF EEG AFTER FIRST SEIZURESection 7 of 12
Electroencephalograms are an important tool in determining prognosis for future seizures and should be strongly considered for all children with a first seizure. If the child is clinically stable, it may not be necessary to perform the EEG on an emergent basis. An EEG does not determine whether or not the patient had a seizure, as this is a clinical diagnosis. In healthy individuals, 10% have an abnormal EEG, whereas 50% of patients with epilepsy have a normal first EEG. Repeating the EEG a second time may increase the sensitivity to 80-90%.6 EEGs may be helpful in classifying seizure types and identifying particular epilepsy syndromes, such as benign rolandic epilepsy or juvenile myoclonic epilepsy. This classification system can help both with prognosis and determining appropriate anticonvulsant therapy. For more information regarding EEG findings in specific childhood epilepsy syndromes, see EEG in Common Epilepsy Syndromes. ROLE OF NEUROIMAGING AFTER FIRST SEIZURESection 8 of 12
If the child has recent head trauma, recurrent seizures, focal or new neurologic deficits, and/or papilledema, neuroimaging should be obtained. Patients who have clearly defined epileptic syndromes, such as petit mal epilepsy or benign rolandic epilepsy, do not necessarily need a brain MRI. The role of neuroimaging in a child with new onset afebrile seizures is controversial. Without stratifying based on history and neurologic exam findings, a recent meta-analysis reports that emergent head CT resulted in a change in acute management in 3-8% of children presenting to an emergency department with a seizure.7 TREATMENTSection 9 of 12
The decision of whether or not to initiate anticonvulsant treatment after a first seizure must be based on the clinical scenario and risks and benefits determined for the individual patient. In general, anticonvulsant drugs are used to decrease the probability of recurrent seizures; however, they have not been found to prevent the development of epilepsy after first seizure.9 In patients presenting in status epilepticus or in acutely ill children (eg, seizures associated with encephalitis), in which the chance of a recurrent seizure is high, medications that can be administered quickly through IV access, such as benzodiazepines, fosphenytoin, phenobarbital, valproic acid, or more recently, levetiracetam, are useful. A prescription for rectal diazepam (Diastat) for use at home if patients have a recurrent prolonged seizure in the future may be useful. In some situations, such as simple febrile seizures, the risks and potential side effects of chronic anticonvulsant therapy are thought to outweigh the benefits, and treatment is not typically offered. The decision of whether or not to treat with chronic anticonvulsant therapy after an unprovoked seizure in a neurologically normal child requires consideration of the risks of medication side effects and psychological stigma against the risk of recurrent seizure on an individualized basis and should involve discussions with the patient and family. As a care guideline, most pediatric neurologists would not start chronic anticonvulsants after a first-time seizure unless prominent risk factors for epilepsy (eg, cerebral palsy, mental retardation, brain structural lesions, abnormal EEG) are known to exist.10, 11 Even if increased recurrence risk is determined, many neurologists would delay starting chronic anticonvulsants until a second seizure occurred, establishing adequate frequency of seizures to warrant medication. If anticonvulsant medications are initiated, the choice of medication should be made based on seizure type. Some medications have been shown to be highly efficacious for some types of seizures but worsen other types. For example, carbamazepine can be helpful against partial seizures but can exacerbate generalized absence seizures. LONG-TERM PROGNOSISSection 10 of 12
Giving a definitive prognosis after a single seizure is difficult, but some general rules do apply, based on epidemiological data. PATIENT EDUCATIONSection 11 of 12
Inform the patient's family about the following:
If a child has a second seizure, place the child in a lateral decubitus position to allow gravity to pull secretions and the tongue out of the airway. Attempt to keep the neck straight to keep the airway most open. Place no objects in the child's mouth. Most seizures last for less than 2 minutes; however, if a seizure lasts more than 5 minutes, the child should be transported to an emergency department for administration of medications to stop the seizures. If the seizure is the second unprovoked seizure (eg, no fever, drug exposure, or proximate head trauma), contact the patient's primary physician or neurologist because anticonvulsant therapy is frequently indicated. Children with the possibility of a having a second seizure should not engage in activities that are potentially harmful. They should not be allowed to take unsupervised baths (because of the risk of drowning) or to climb higher than 5 feet. Supervised swimming, bike riding (helmeted), and playing video games are considered by most neurologists to be safe activities. Driving age patients should refrain from driving until deemed safe and seizure-free, according to the laws of their state. For instance, in the State of Wisconsin, patients need to be seizure-free for 3 months before they can resume driving, whereas in Arkansas, patients need to be seizure-free for 1 year. After a single seizure, an appointment should be made with the child's primary care physician or a neurologist. This is useful to address any further questions the family has, review the need for further diagnostic testing, and discuss any further therapy. Families should also be encouraged to learn basic CPR. Direct families of patients to reliable sources of information. The Epilepsy Foundation of America provides comprehensive information. For excellent patient education resources, visit eMedicine's Brain and Nervous System Center. Also, see eMedicine's patient education article Epilepsy. REFERENCESSection 12 of 12
First Seizure: Pediatric Perspective excerpt Article Last Updated: Jun 20, 2008 |
