Eclampsia, hippocampal sclerosis, and temporal lobe epilepsy: Accident or association?

The landscape of disparities in obstetric neurocritical care and a path forward

Health disparities in the obstetric population affect maternal morbidity and mortality. In the past years, there has been no significant improvement in disparities in care in the obstetric population. Patients who are pregnant are known to have a higher risk of pregnancy-associated neurologic conditions such as stroke and intracerebral hemorrhage. They can also experience concomitant neurocritical care disease states such as status epilepticus and traumatic brain injury. Studies exploring the disparities of care among pregnant patients who are neurotically ill are lacking. We aim to provide the landscape of disparities of care among the obstetric neurocritically-ill population and provide potential actionable opportunities to address these disparities in care.

Factors associated with anti-seizure medication utilization for eclamptic seizures: 1995-2015

OBJECTIVE

We sought to ascertain the drivers of the use of anti-seizure medications (ASMs) other than magnesium sulfate (MgSO4) in seizure management in a cohort of pregnant and postpartum women with eclamptic seizure.

METHODS

Cases of seizure activity attributed to eclampsia from 1995-2015 at 2 large urban academic medical centers were identified and reviewed by a neurologist and an obstetrician. Analyses focused on patterns of ASM utilization among women according to timing, recurrence, posterior reversible encephalopathy syndrome, and specialty consultation with additional sub-analysis focusing on recurrent seizures only.

RESULTS

93 cases of eclampsia were identified. 100% of subjects received MgSO4. 52% of women received an ASM in addition to MgSO4. Subjects with seizures occurring post-partum, with >1 seizure, or who had a formal neurology consult were more likely to receive an ASM in addition (risk ratio [RR] 3.05 [95% confidence interval [CI] [1.30-7.11], RR 3.01 [95% CI 1.29-7.02], and RR 6.29 [2.37, 16.71] respectively). Postpartum recurrent seizures or those receiving a neurology consult were also more likely to be treated with ASMs compared to recurrent or comanaged seizures occurring before delivery (RR 1.55 [1.02, 2.37] and 1.65 [1.02, 2.69]).

CONCLUSIONS

In this retrospective cohort, patients with atypical seizure presentation (e.g., postpartum and/or recurrent) and women who were comanaged with a neurologist were more likely to receive an ASM other than MgSO4.

Neuropathophysiology of preeclampsia and eclampsia: A review of cerebral hemodynamic principles in hypertensive disorders of pregnancy

Preeclampsia and eclampsia are hypertensive disorders of pregnancy associated with abnormal placental vascular development. The systemic angiogenic imbalance, endothelial dysfunction and proinflammatory state caused by abnormal placental development results in abnormalities in renal, hepatic, pulmonary and neurologic function. Neurosensory symptoms related to pregnancy induced hypertension (PIH), the most devastating of which are intracranial hemorrhage and seizure, are among the leading causes of maternal and perinatal morbidity and mortality globally, yet risk stratification strategies and targeted therapies remain elusive. Current treatment for preeclampsia with severe features is limited to delivery, antihypertensive therapy, and magnesium sulfate seizure prophylaxis. Magnesium sulfate reduces seizure rates among severe preeclamptics, but predisposes patients to weakness, uterine atony, pulmonary edema and respiratory depression. Therefore, this drug should ideally be administered only to the subset of preeclamptics who are at increased risk for neurologic complications. While there are no objective methods validated to predict eclampsia, we hypothesize that measurement of optic nerve sheath diameters, optic disc height and middle cerebral artery transcranial doppler resistance indices may be useful in identifying subclinical cerebral edema, potentially allowing us to recognize those patients at highest risk for seizures. This summary of the current literature provides an initial framework for developing more sophisticated and noninvasive methods for identifying, monitoring and treating parturients who are at highest risk for neurologic complications from preeclampsia.

Long-term seizure recurrence after eclampsia: A systematic review and meta-analysis

BACKGROUND

Seizure recurrence after a fit has implications for both individuals and healthcare providers guiding neurologic prognosis, treatment, and driving and work restrictions. A systematic review of long-term seizure recurrence after eclampsia will help to quantify recurrence risk in this setting.

OBJECTIVE

To evaluate the long-term recurrence of seizures after eclampsia.

SEARCH STRATEGY

After PROSPERO registration, Medline (Ovid), Embase, and Cochrane Library were searched by using the terms (eclampsia OR eclamp* OR eclamptic seizure* OR eclamptic fit*) AND (recur* OR recurrent fit* OR recurrent seizure*) for studies published up until December 2019.

SELECTION CRITERIA

Studies describing long-term seizure recurrence after a diagnosis of eclampsia were included.

DATA COLLECTION AND ANALYSIS

Data were extracted from studies independently by two authors. Pooled prevalence was calculated and weighted based on sample size with a 95% confidence interval (CI).

MAIN RESULTS

Initially, 1754 unique studies were identified and 4 were included in the final analysis. The studies involved 1896 women, of whom 7 (0.37%) were affected by a further seizure. The weighted pooled prevalence of seizure recurrence was 0.18% (95% CI, 0.03-1.02).

CONCLUSION

The absolute rate of long-term seizure recurrence after eclampsia is extremely low and within safe limits for driving.

Development of epilepsy after posterior reversible encephalopathy syndrome

PURPOSE

This study was intended to describe the risk of epilepsy subsequent to posterior reversible encephalopathy syndrome (PRES) and the clinical features of post-PRES epilepsy.

METHOD

We retrospectively identified all patients with PRES who were admitted to Severance Hospital and consulted with the Department of Neurology between 2001 and 2013 and the subgroup of these patients who subsequently developed epilepsy. We also describe clinical features of patients who were not treated with PRES as inpatients at our center but who presented later with post-PRES epilepsy during the study period. We studied clinical characteristics during the acute symptomatic phase of PRES and after the development of epilepsy.

RESULTS

During the study period 102 patients were treated at our center during the acute phase of PRES. Four of these patients (3.9%) subsequently developed epilepsy. Two additional patients with a history of PRES presented to our hospital after the acute phase of their illness with post-PRES epilepsy. During the acute phase, five of six patients had acute symptomatic seizures and four had convulsive or nonconvulsive status epilepticus (SE). Acute phase MRI showed cytotoxic edema in five patients, and follow-up MRI showed focal atrophic changes including hippocampal sclerosis in four. Presumptive epileptogenic foci were located in the left-side temporal, parietal and occipital lobes, corresponding to the regions that showed cytotoxic edema or severe vasogenic edema as well as with the location or lateralization of EEG abnormalities during the acute phase.

CONCLUSION

Our findings indicate a small but not insignificant risk for the development of epilepsy after PRES. The presence of cytotoxic edema and severe, acute symptomatic seizures, such as SE suggests irreversible brain damage and may predict the development of epilepsy.

Comparison of precipitating factors for mania and partial seizures: Indicative of shared pathophysiology?

OBJECTIVES

Mania in bipolar disorder (BD) and partial (focal) seizures (PS) arising from the temporal lobes, have a number of similarities. Typically, a chronic course of the disorders is punctuated by acute illness episodes. Common features of episodes may include sensory, perceptual, cognitive and affective changes. Both respond to anticonvulsant treatment. Common mechanisms imputed include neurotransmitters and kindling processes. Further investigation may improve understanding of the occurrence of both mania and PS, casting light on the relevance of temporal lobe mediated processes and pathology. One avenue of investigation is to compare aetiological factors and determine the extent of overlap which may indicate shared brain localization or pathophysiology. Aetiology includes predisposing, precipitating or perpetuating factors. This paper examines the literature on precipitating factors of mania, first or subsequent episode, and of PS in diagnosed epilepsy, which is the second or subsequent seizure, to identify the extent and nature of their overlap.

METHOD

Narrative review based on a literature search of PubMed and Google Scholar.

RESULTS

Precipitating factors for both mania and PS were stress, sleep deprivation, antidepressant medication and, tentatively, emotion. For mania alone, goal-attainment events, spring and summer season, postpartum, and drugs include steroids and stimulants. For PS alone, winter season, menstruation and specific triggers in complex reflex epilepsies. Those not substantiated include lunar phase and menopause. A wide range of chemicals may provoke isolated seizures but by definition epilepsy requires at least two seizures.

CONCLUSIONS

The overlap of precipitating factors in mania and PS imply that common brain processes may contribute to both, consistent with findings from neuroscience research.

Neurology of pregnancy

Pregnancy creates alterations in maternal physiology which predispose to unique neurologic disorders. Pre-eclampsia, eclampsia, certain types of ischemic and hemorrhagic stroke, reversible cerebral vasoconstriction syndrome, posterior reversible encephalopathy syndrome, and thunderclap headache all appear to share a common origin from vascular endothelial dysfunction, with overlapping clinical presentations. Multiple sclerosis often improves during pregnancy. Compression mononeuropathies may occur in the extremities. Myasthenia gravis may affect second stage labor. Various inflammatory peripheral neuropathies, dystrophies, myopathies may occur during pregnancy. The safety of specific immune suppressants is reviewed. Epilepsy does not have a significant effect upon the course of pregnancy, albeit there is a modest increase in the need for cesarean section. Certain antiepileptic drugs may produce fetal malformations, most notably valproic acid. Brain tumors are rare during pregnancy, but may increase in size due to activation of hormonal receptors on tumor cells surfaces, water retention, and engorged blood vessels.

The conundrum of eclampsia and fitness to drive

BACKGROUND

Australian Fitness to Drive guidelines suggest that anyone who has had a seizure of any kind in the context of a 'metabolic' disorder should avoid driving for a period of 6 months. The special case of eclampsia is not mentioned.

AIMS

In this study, we aimed to assess what advice healthcare professionals involved in the peripartum care of women provide to women who have an eclamptic seizure, what investigations they would conduct to exclude other causes of seizures and their level of awareness of whether eclampsia was addressed in the Australian Fitness to Drive guidelines.

MATERIALS AND METHODS

A survey of 165 healthcare professionals attending the 2012 Society of Obstetric Medicine of Australia and New Zealand annual scientific meeting. Participants included registered nurses, midwives, consultant obstetricians, consultant physicians, doctors in training and others, interested in medical disorders of pregnancy.

RESULTS

One hundred and nine conference attendees completed the survey (response rate 66.1%). 58 respondents (53.2%) had cared for 5 or more women with peripartum seizures, and 23 respondents (21.1%) had cared for 10 or more women with peripartum seizures. 46 respondents (42.2%) had never considered the issue of driving after an eclamptic seizure. For those who had considered the issue, advice ranged from no restriction (n = 5, 4.6%), no driving for 1-2 weeks (n = 14, 12.8%), no driving for 3 months (n = 20, 18.4%) or no driving for 6 months (n = 6, 5.5%).

CONCLUSIONS

Many healthcare professionals caring for women with peripartum seizures have not considered issues relating to fitness to drive after an eclamptic seizure. There is a wide range of advice provided. Better prospective data are required regarding the risk of subsequent seizure after eclampsia, to inform clear fitness to drive guidelines.

Occipital lobe epilepsy secondary to posterior reversible encephalopathy syndrome (PRES) during a post-partum eclampsia in Mali (West Africa)

Background

Eclampsia is known to cause posterior reversible encephalopathy syndrome (PRES) that is often associated with an extensive neurovascular damage affecting preferably posterior regions, often leading to reversible cortical blindness. In spite the magnitude of these lesions, post eclamptic symptomatic epilepsy is rare. We therefore report a case of symptomatic occipital lobe epilepsy secondary to PRES.

Case presentation

A 39-year-old female right handed teacher who presented with headache of progressive onset, phosphenes, rapid decline of visual acuity to blindness, vomiting, repeated generalized tonic-clonic seizures followed by altered consciousness and very high blood pressure (HBP) of 240/120 mmHg, all of which started about 12 hours following a normal delivery. Nine months later, the patient presented with paroxysmal visual symptoms predominating in the right visual field followed by partial tonic clonic seizures with secondary generalization and recurrence of partial occipital lobe seizures. The pathophysiologic mechanism of irreversible tissue damage during PRES syndrome could result from a combination of events including the delay for early treatment, inadequate antihypertensive drugs that could worsen the brain damage by hypo perfusion, inadequate or delayed treatment for seizures or status epilepticus.

Conclusion

Despite its high incidence in the third world, eclampsia is not a usual cause of epilepsy. Our case is the first description of post eclamptic occipital lobe epilepsy in Africa. With this report, we draw practitioners’ attention on this rare complication.

Posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is characterized by headache, altered mental status, visual disturbances, and seizures. Radiological features typically include edema of the posterior cerebral regions, especially of the parietooccipital lobes. Atypical imaging features, such as involvement of anterior cerebral regions, deep white matter, and the brain stem are also frequently seen. Vasoconstriction is common in vascular imaging. Different conditions have been associated with PRES, but toxemia of pregnancy, solid organ or bone marrow transplantation, immunosuppressive treatment, cancer chemotherapy, autoimmune diseases, and hypertension are most commonly described. The pathophysiology of PRES is unclear and different hypotheses are being discussed. Posterior reversible encephalopathy syndrome is best managed by monitoring and treatment in the setting of a neurointensive care unit. The prognosis is usually benign with complete reversal of clinical symptoms within several days, when adequate treatment is immediately initiated. Treatment of severe hypertension, seizures, and withdrawal of causative agents represent the hallmarks of specific therapy in PRES. Delay in diagnosis and treatment may lead to permanent neurological sequelae. Therefore, awareness of PRES is of crucial importance for the intensivist.

Neurologic complications of pre-eclampsia

Pre-eclampsia is mainly responsible for the world's large maternal mortality rates, mostly due to acute cerebral complications. This review provides insight into the pathogenesis of the neurologic complications of hypertensive disease in pregnancy. In addition, practical relevance for clinical care is highlighted. Pertaining to pregnancy, the blood pressure level at which cerebral autoregulation operates and possible deregulation occurs is unknown, but is likely to be variable. From clinical observation, eclampsia may occur despite a mild clinical picture and before the development of hypertension or proteinuria. Furthermore, failure of cerebrovascular autoregulatory mechanisms in response to either an acute and/or relatively large blood pressure increase may be more important than the absolute blood pressure value. It may be the acuity of the blood pressure rise in the setting of endothelial dysfunction that interrupts the delicate balance between capillary and cellular perfusion pressures that leads to the neurological complications of pre-eclampsia.

Eclampsia: a neurological perspective

Eclampsia is a poorly understood disorder characterized by seizures or unexplained coma in setting of gestational hypertension. Its neurological manifestations are varied and are an important cause of the morbidity and mortality associated. We present a comprehensive prospective study of forty women recruited over four years describing neurological symptoms and signs, neuroimaging and laboratory studies as well as prognosis including 3-6 months follow-up. The seizures occurred in the postpartum period in majority of women (55%), while 45% had seizures before labor, and the rest (5%) during labor. Interestingly, one third of the women suffered their first seizures more than 48 h postpartum (late postpartum eclampsia). A sizable minority suffered more than one seizure and some had documented partial seizures. Headache preceded seizures by more than a day and was described as throbbing or pounding pain by most. The visual symptoms in decreasing frequency were blurring, blindness, scotoma and visual processing deficits. The most common finding during the neurological exam was memory deficits, followed by increased deep tendon reflexes (asymmetric in some), visual perception deficits, visual information processing deficits, altered mental status and cranial nerve deficits. Intracranial or intraspinal pressure when examined was elevated. Among neuroimaging studies, MRI was more sensitive compared to CT scan. The MRI abnormalities included both white as well as gray matter and the most common location of abnormalities was high frontal/parietal lobe. The laboratory studies revealed proteinuria in majority, but not in all. The liver function tests were abnormal in many, while few patients had HELLP syndrome. The neurological deficits resolved by the time of discharge in all. At follow-up, some patients developed new neurological problems such as recurrent headaches or seizures.

Early seizures: causal events or predisposition to adult epilepsy?

Past studies have been unable to confirm whether early seizures predispose to epilepsy in adults. Seizures in infancy were classically thought to cause brain lesions that led to epilepsy in adulthood. However, these infants were not thought to have epilepsy, but acute events that included seizures. Accumulating evidence suggests that early seizures may be associated with, or cause, brain damage; or alternatively, they may be the first expression of a genetic or lesional predisposition to epilepsy. The course of early seizures ranges from transient to life-long, depending on epilepsy syndrome, causes, and treatment. The main factors that determine late or persisting epilepsy after the occurrence of early seizures are protracted seizures, tonic seizures, and involvement of mesial temporal structures. A developmental approach to seizure disorders will aid understanding of epilepsy in adults and improve the design of antiepileptic agents for children and adults.

Racial/ethnic disparities in the treatment of epilepsy: what do we know? What do we need to know?

We examine current understanding of the minority disadvantage in the clinical management of epilepsy. We performed an online literature search using several keywords (race, ethnicity, epilepsy, treatment, and quality of life) and identified additional literature through cross-referencing/manual search. The search produced 58 items published between 1977 and 2005. Of 49 original research studies, 38 were quantitative, 7 were qualitative, and 4 used mixed methods. Three or more articles were published in Epilepsia, Epilepsy &Behavior, Epilepsy Research, Neurology, and Seizure. Research concerning racial/ethnic differences in epilepsy treatment is scarce and limited by methodology, but suggests underutilization of state-of-the-art therapies by minorities. Racial/ethnic minorities also appear to have limited knowledge about epilepsy and its treatment, experience barriers to care, lack social support, and seek alternative therapies for epilepsy. We propose a framework to identify the array of disparities, points of intervention, and interventions.

Race/ethnicity: a predictor of temporal lobe epilepsy surgery outcome?

PURPOSE

The success of epilepsy surgery in temporal lobe epilepsy reaches a 64% rate of seizure freedom, based on a randomized control trial. Observational studies from epilepsy centers worldwide indicate seizure freedom rates up to 93% when the etiology is unilateral hippocampal sclerosis. Several risk factors are attributed to the recurrence of seizures following the surgical procedure. Nonetheless, whether race influences the outcome of temporal lobe surgery is unknown. The purpose of this study was to evaluate if race plays a role in outcome following surgery.

METHODS

Data were obtained from the discharge database of the University of Alabama at Birmingham video/EEG monitoring unit, between 1998 and 2003, as well as the clinical charts. Seizure recurrence was evaluated 1 year following surgery. The sample consisted of all patients with a primary diagnosis of mesial temporal sclerosis (MTS) who underwent anterior temporal lobectomy. Multiple logistic regression analysis was used to model the presence of seizure recurrence after anterior temporal lobectomy for MTS. Two sets of logistic regression models were estimated to generate odds ratios (ORs) for seizure recurrence after an anterior temporal lobectomy for African-Americans or other possible ethnic/racial group present relative to non-Hispanic Caucasians. The first model incorporated only ethnicity as the independent variable and generated unadjusted ORs for seizure recurrence following the surgical procedure. The second set included the independent variables: duration of epilepsy, history of febrile seizures, lateralization of epileptogenic focus, handedness, and age.

RESULTS

Seventy patients underwent surgical treatment and all of them had pathologic confirmation of MTS. Follow-up information for six was not available. Analysis of the remaining 64 patients revealed that African-Americans were more likely than non-Hispanic Caucasians to have seizure recurrence after surgery (OR=2.1, 95% CI=0.6-8.0). After potential confounders (duration of epilepsy, history of febrile seizures, lateralization of epileptogenic focus, handedness, and age) were controlled, this finding did not change (OR=1.7, 95% CI=0.3-10.7).

CONCLUSION

Our data suggest that race may be an important factor related to seizure outcome following temporal lobectomy.