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Eclampsia 1 de 19 Official reprint from UpToDate® Print | Back Eclampsia Author Errol R Norwitz, MD, PhD Section Editor Charles J Lockwood, MD Deputy Editor Vanessa A Barss, MD Last literature review for version 17.1: enero 1, 2009 | This topic last updated: noviembre 13, 2008 INTRODUCTION — Eclampsia refers to the occurrence of one or more generalized convulsions and/or coma in the setting of preeclampsia and in the absence of other neurologic conditions [1]. The clinical manifestations can appear anytime from the second trimester to the puerperium. In the past, eclampsia was thought to be the end result of preeclampsia (hence the nomenclature); however, it is now clear that seizures should be considered merely one of several clinical manifestations of severe preeclampsia (show table 1), rather than a separate disease. Despite advances in detection and management, preeclampsia/eclampsia remains a common cause of maternal death [2]. The diagnosis and management of eclampsia will be reviewed here. Issues related to preeclampsia are discussed separately. (See "Pathogenesis of preeclampsia", see "Clinical features, diagnosis, and long-term prognosis of preeclampsia", see "Management of preeclampsia", and see "Prevention of preeclampsia"). INCIDENCE AND EPIDEMIOLOGY — An eclamptic seizure occurs in approximately 0.5 percent of mildly preeclamptic women and 2 to 3 percent of severely preeclamptic women [3]. The incidence of eclampsia has been relatively stable at 4 to 6 cases per 10,000 live births in developed countries [4,5,53]. In developing countries, however, the incidence varies widely: from 6 to 100 cases per 10,000 live births [6]. Risk factors for eclampsia are similar to those for preeclampsia (show table 1A). Nonwhite, nulliparous women from lower socioeconomic backgrounds are the group at highest risk of developing eclampsia. Peak incidence is in the teenage years and low twenties, but there is also an increased incidence in women over 35 years of age. Timing in pregnancy — Eclampsia prior to 20 weeks of gestation is rare and should raise the possibility of an underlying molar pregnancy or antiphospholipid syndrome. (See "Gestational trophoblastic disease: Epidemiology, clinical manifestations and diagnosis" and see "Obstetrical manifestations of the antiphospholipid syndrome"). Approximately one-half of all cases of eclampsia occur prior to term, with more than one-fifth occurring before 31 weeks of gestation [4]. Just over one-third of cases occur at term, developing intrapartum or within 48 hours of delivery. Late postpartum eclampsia (ie, eclamptic seizures developing greater than 48 hours, but less than four weeks postpartum) accounts for the remainder (13 to 16 percent) and represents as many as one-quarter of all postpartum cases [7-9]. Looked at in another way, the timing and frequency of eclampsia is antepartum (38 to 55 percent), intrapartum (13 to 36 percent), less than or equal to 48 hours postpartum (5 to 39 percent), and greater than 48 hours postpartum (5 to 17 percent) [5,10]. PATHOGENESIS OF SEIZURES — The exact cause of seizures in women with eclampsia is not known. The following two hypotheses have been proposed [11]: Cerebral overregulation in response to high systemic blood pressure results in vasospasm of cerebral arteries, underperfusion of the brain, localized ischemia/infarction, and


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