FEBRILE SEIZURES Febrile seizure – seizure occurring in healthy children ages 3 months to 6 years, with axillary temperature of 37.8 C or greater, without evidence of CNS infection. Seizures with fever in children with previous nonfebrile seizures, a previous diagnosis of neurologic insult or abnormality, and an abnormal neurologic examination are excluded. SIMPLE FEBRILE SEIZURE
A. DEFINITION DEFINITION Simple febrile seizure is seizure characterized as generalized (usually tonic-clonic), lasting for <15 minutes and which does not recur within the same febrile illness. B. TREATMENT TREATMENT The current recommendation is not to routinely treat children with simple febrile seizures with anticonvulsants. One should weigh the side effects of the drug versus therapeutic effects. The only medications effective in controlling seizures are benzodiazepines and valproic acid. For recurrent febrile seizures, one may opt to give diazepam 0.5mg/kg/dose q12 hrs to a maximum of 4 doses during febrile states of 38C and above. Summary of Recommendations Philippine Clinical practice Guidelines on first Febrile Seizure Philippine Pediatric Society-Child Neurology Society Philippines, Inc 1. Lumbar puncture puncture should should be performed in all all children below 18 m months onths for a first febrile seizure. For those children >/= 18 months of age, lumbar puncture should be performed in the presence of clinical signs of meningitis (eg. (+) meningeal signs, sensorial changes). 2. Neuroimaging Neuroimaging studies studies should not be routinely routinely performed performed in children for for a first simple febrile seizure. 3. Antipyretic Antipyretic drugs are used to lower lower the fever and should should not be relied upon upon to prevent the recurrence of febrile seizures. 4. The use of continuous continuous anticonvulsant anticonvulsants s is not recommended recommended in children after after a first simple febrile seizure. Although anticonvulsants can reduce the recurrence of febrile seizures, the adverse side effects of these do not warrant their use in this benign disorder. 5. The use of intermittent anticonvulsant (whether Phenobarbital or diazepam) is not recommended for the prevention of recurrent febrile seizures. 6. EEG should not be routinely requested in children with a first simple febrile seizure.
COMPLEX FEBRILE SEIZURE A. DEFINITION Complex febrile seizure with partial onset, prolonged duration (lasting >10 or >15 minutes, both have been used) and recurrent (more than 1 seizure in a single illness episode, generally in a 24-hour period). It occurs in 20-38% of all children with febrile seizures, 4-15% of children with complex febrile seizures develop epilepsy. B. TREATMENT Unlike simple febrile seizures, no guidelines have been proposed for the management of the first complex febrile seizure. The role of EEG, neuroimaging studies and treatment are still unclear. Based on some studies, majority of which are retrospective, the following may be considered: 1. Just like patients with the first simple febrile seizure, a child with the first complex febrile seizure <2 years old should undergo lumbar tap in order to rule out the presence of meningitis, unless a contraindication in doing the procedure is present such as signs of increased intracranial pressure. 2. Doing a routine EEG is not recommended. However, there are some predictive factors of abnormal EEGs in children with complex febrile seizures: Age > 3 years EEG performed between 7-10 days Abnormal neurological examination 3. No studies have shown that the presence of abnormality on CT scan/MRI could predict seizure recurrence in patients with the first complex febrile seizures. However, a study has shown that abnormal neuroimaging studies are more likely to be seen in patients with abnormal EEG findings. 4. In terms of epilepsy prevention, there are no studies yet showing that treatment of febrile seizure, whether simple or complex, can prevent epilepsy.
NEURODIAGNOSTIC EVALUATION IN PATIENTS WITH SEIZURES The extent of the laboratory work-up for patients with seizure problems is dependent on the suspected etiology of the seizures. The following are commonly requested laboratory tests: A. ELECTROENCEPHALOGRAM (EEG) To confirm clinical diagnosis of epilepsy, to accurately determine seizure type, and to determine focus of seizure (localization) Indicator of cerebral dysfunction and measure of severity disturbance Maturational pattern of background activity Monitoring of response to treatment •
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B. NEUROIMAGING Neuroimaging is done in evaluating patients suspected of having structural lesions 1.
CRANIAL ULTRASOUND is safe and easily available tool to check for hydrocephalus, complications of CNS infections such as subdural effusion/empyema and ventriculitis, acute intracranial bleed and cerebral edema in neonates and infants with open anterior fontanelle.
2.
SKULL X RAY has limited value in the evaluation of seizures.
3. CRANIAL CT (Computed Tomography) SCAN is the preferred imaging modality of choice if one is looking for calcifications (TORCH), acute bleed, acute infections. Contrast studies should always be requested unless contraindicated. 4. SPIRAL CT (3-D CT) is the preferred imaging for evaluating craniosynostosis
5. MAGNETIC RESONANCE IMAGING (MRI) is preferred over CT scan in evaluating for parenchymal anomalies and other malformation as in the ff: a. mesial temporal sclerosis b. cortical dysplasia and other migration disorders c. vascular malformations d. neoplasia e. posterior fossa lesions 6. MRA and ANGIOGRAPHY are usually reserved for patients suspected of vascular anomalies 7. SPECT (Single Photon Emission Computed Tomography) is used to measure cerebral blood flow and for presurgical evaluation patients with refractory seizures who arte candidates for epilepsy surgery
8. POSITRON EMISSION TOMOGRAPHY (PET) uses positron-emitting isotopes like fluorodeoxyglucose (FPG) which reflects alteration in metabolic demands of neurotransmitter activity. C. CSF ANALYSIS Contraindications: o Infection at site of puncture o Coagulopathies Increased intracranial pressure o Cervical cord lesions o Suspected or known intracranial mass o Severe cardiovascular compromise o
D.VIDEO EEG MONITORING Indications: Confirmation of clinical diagnosis of epilepsy in patients with o suspicion of pseudoseizures. Accurate determination of seizure type o Determination of sleep cycles. o
DRUG THERAPY Principles of drug therapy Objective: - To prevent recurrence by prescribing the appropriate anticonvulsant Drug of Choice In The Treatment of Seizure Seizure Type
First Choice
Second Choice
Carbamazepine Phenytoin Valproic Acid Oxacarbazepine Carbamazepine Phenytoin Valproic Acid Oxacarbazepine
Gabapentin Lamotrigine Phenobarbital Topiramate Gabapentine Lamotrigine Phenobarbital Topiramate
Myoclonic
Carbamazepine Phenytoin Valproic Acid Phenobarbital (phils) Ethosuximide Valproic Acid Valproic Acid
Clonic Tonic
Valproic acid Valproic acid
Atonic
Valproic acid
Gabapentin Lamotrigine Phenobarbital Topiramate Lamotrigine Topiramate Clonazepam Phenobarbital Phenobarbital Carbamazepine Lamotrigine Phenytoin Topiramate Lamotrigine Topiramate
Partial Simple Partial
Complex Partial
Generalized SZ GTC
Absence
