| Abstract: |
Background: Epilepsy is a serious brain disorder characterized by recurrent provoked or unprovoked seizures. Seizures are the most frequent clinical sign of neurological dysfunction in the neonate. The mechanisms of seizures in newborns are complex and not well understood, as a result theories of epileptogenesis are rapidly evolving. The immature brain of a newborn is likely more susceptible to seizures because of characteristics of the neurons, neurotransmitters, receptors, synapses, myelination, glia, cellular function and neuronal circuitry. The following factors were reported to be significant for seizures occurring in term infants within the first 48 hours of birth: nulliparity, hydramnios, post-term pregnancy, oxytocin augmentation of labor, fetal distress, prolonged second stage of labor, emergency cesarean section, assisted vaginal delivery, low Apgar score, resuscitation at delivery, and subsequent ventilatory support. Determination of etiology is highly critical because it affords the opportunity to treat specifically and also to make a meaningful prognostic statement. The primary causes are hypoxic ischemic insult, intracranial hemorrhage, cerebral infarction, meningitis and congenital abnormalities, other causes include: inborn error of metabolism, hypoglycemia and hypocalcemia, less common causes include: pyridoxine dependency, neonatal drug withdrawal, and benign familial neonatal seizures; however a small percentage is idiopathic. Neonatal seizures are classified as subtle, tonic, clonic or myoclonic. Diagnosis is made by laboratory study as serum glucose, serum calcium, magnesium, sodium, CSF analysis or TORCH screening and imaging study as cranial ultrasound, CT scan, MRI, EEG, cerebral function monitor and novel neuroimaging techniques as magnetic resonance spectroscopy. The initial goal of therapy is to control the seizures by treating the underlying etiology. This is often a difficult task, as in some cases the cause of seizure cannot be identified, there may be no known treatment or the seizures may not be controllable with aggressive therapy. Treatment choices may be corrective therapies as for hypoglycemia, hypocalcemia, hypomagnesemia, hyponatremia or hypernatremia, pyridoxine dependency and may be by antiepileptic medications. Antiepileptic medications include phenobarbitone as the first line treatment option, phenytoin (better fosphenytoin), benzodiazepines or new agents as topiramate, and other options under trial as bumetanide. For refractory cases, lidocaine and paraldehyde had been used.The range of outcome of neonatal seizures varies widely with the three major predictors of long-term outcome being: the underlying etiology, the electrographic features and the gestational age.Objectives: The aim of the work is to provide an updated review of neonatal seizures. All aspects of the problem will be covered in a recent comprehensive way to shed light on this critical neonatal problem. Recent diagnostic approaches and therapeutic interventions will be reviewed.
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