الفهرس 
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Abstract
Febrile seizures are defined as seizures that occur in association br with a fever in children 6 months to 5 years of age, but in whom there is br no evidence of a central nervous system infection or another definable br cause of seizure, and which are not preceded by a history of an afebrile br seizure (Alexander and lane, 2007). br Febrile seizures are the most common form of childhood seizures, br affecting approximately 2–5% of children. Usually occur between 3 br months and 5 years of age, with a-peak incidence at 18 months, Boys are br affected slightly more often than are girls (Millar, 2006). br Febrile seizures are usually categorized as either simple or br complex. A simple FS is defined as a self-limiting tonic-clonic seizure of br short duration (-lt;15 min) that does not usually recur within the next 24 h, br and that does not leave any postictal pathology. On the other hand, a br complex FS is defined as having, A focal onset or focal features during br the seizure, Prolonged duration (-gt;15 min), Recurrent seizures within the br same febrile illness over a 24-h period, Previous neurological br impairment, such as cerebral palsy or developmental delay (Fetveit, br 2008). br Risk factors include a first-degree relative with a history of a br febrile seizure, a neonatal nursery stay of more than 28 days, br developmental delay, and attendance at a day care center . Approximately br 30% to 40% of children who experience a febrile seizure will have a br recurrence, but less than 10% will have three or more recurrences. br Various risk factors for recurrences of febrile seizures have been br identified and include a younger age of onset (15 months), relatively br lower temperature at the time of the first febrile seizure, shorter interval br between the onset of fever and the initial seizure, epilepsy in a firstdegree br relative, febrile seizure in a first-degree relative, frequent febrile br -73- br illnesses (day care attendance), and a first febrile seizure that is complex . br The greater the number of risk factors, the higher is the rate of recurrence br (Alexander and lane, 2007). br The etiology and pathogenesis of febrile seizures have yet to be br fully elucidated, particularly at the molecular level. However, some br environmental aspects are already understood and believed to be essential br to development of the condition , The underlying cause of the infectious br process does not appear to be a determining factor of febrile seizures, br The presence of fever is of course essential, even though its mechanism br of action is unknown. Febrile seizures are also most common in the first br day of fever, and correlate more with peak temperature than with speed of br onset ( Luis Felipe , 2010). br There is a genetic predisposition to febrile seizures. The risk for br the development of a febrile seizure is approximately 20% when asibling br is affected, and the risk increases to 33% when both parents also are br affected , Recently, several mutations in the GABAA receptor _2 subunit br gene have been reported to be associated with febrile seizures (Kang et br al.). These receptors mediate the majority of fast synaptic inhibitions in br the brain (kang et al., 2006). br The seizure threshold varies between individuals. Children prone to br febrile seizures produce more proinflammatory cytokines in the central br nervous system, such as interleukin-1, which might induce seizures. br The type of infection plays a role in the pathogenesis. Roseola br infantum (exanthem subitum), caused by human herpesvirus 6, is an br important cause of first-time febrile seizures . Viral upper respiratory br tract infection, otitis media, pharyngitis, and gastroenteritis (especially br due to shigellosis) are other important causes of febrile seizures. br Influenza A infection is associated with a higher incidence of febrile br seizures and of recurrent seizures during the same febrile episode than are br -74- br infections with adenovirus or parainfluenza (Alexander and lane, br 2007). br Vaccination against diphtheria, tetanus, and pertussis is an.