Posterior reversible encephalopathy syndrome in preeclampsia and eclampsia: The role of hypomagnesemia

Posterior Reversible Encephalopathy Syndrome and Eclampsia in the Setting of Magnesium Toxicity: A Case Report

Posterior reversible encephalopathy syndrome (PRES) is a rare neurologic condition and a feared complication of eclampsia. It is evidenced by acute neurologic dysfunction secondary to cerebral edema and is typically reversible in nature. Although it is a relatively new diagnosis, an increasing amount of literature has described its occurrence, including an association with hypomagnesemia. We present a case wherein a 24-year-old parturient developed PRES and eclampsia in the setting of symptomatic hypermagnesemia, requiring management with lorazepam after seizures developed. Here we detail her clinical course, including the unique challenges of treating eclampsia and PRES in the setting of magnesium toxicity.

A Rare Association of Hypomagnesemia and Posterior Reversible Encephalopathy Syndrome (PRES)

Posterior reversible encephalopathy syndrome (PRES) is a rare neurologic disorder that presents with variable symptoms and symmetrical abnormal white matter signaling most commonly of the occipital and parietal lobes on magnetic resonance imaging (MRI). PRES, also known as reversible posterior leukoencephalopathy syndrome (RPLS) is commonly associated with hypertension. Hypomagnesemia's association with PRES has been rarely reported. Here, we report a patient with severe hypomagnesemia that presented with PRES syndrome that improved with magnesium replacement. Hypomagnesemia should be considered an underlying etiology in patients presenting with PRES syndrome and should be promptly treated. The presentation can often be concerning for acute cerebrovascular accidents with symptoms of dysarthria and upper motor neuron symptoms, such as facial droop, dysarthria, and gait instability. Differential diagnosis of PRES often includes rostral brainstem infarction, transient ischemic attack, infectious encephalopathy, and metabolic/toxic encephalopathy, which is evaluated in the description of the case. The most common presentation of RPLS/PRES includes altered mental status, drowsiness, seizure, vomiting, alterations in speech including dysarthria, and visual disturbance. The first signs noted are commonly lethargy and somnolence. In this case, the patient presented notably with initial symptoms of dysarthria of speech and facial droop, with serum hypomagnesemia in which symptoms corrected rapidly with the administration of intravenous magnesium sulfate.

Status epilepticus in pregnancy

Status epilepticus is a frequent neurological emergency associated with a case fatality of about 10-15% depending on age, cause, and other factors, and a high burden for patients, caregivers, and society. In pregnancy, it can occur in two different clinical constellations: (1) In women with a history of epilepsy and (2) as new onset status epilepticus in pregnancy (NOSEP). Both entities are relatively rare but differ in terms of etiology. Here we describe the epidemiology, etiologies, diagnosis, clinical course with the maternal and fetal outcome, and the suggested management strategies for either manifestation. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Posterior Reversible Encephalopathy Syndrome: A Review of the Literature

Posterior reversible encephalopathy syndrome (PRES) is a group of clinical syndromes typically characterized by bilateral reversible vasogenic edema of the subcortical white matter in the parieto-occipital region on neuroimaging that causes a wide variety of acute or subacute neurological symptoms, including headache, mental status alteration, seizures, and visual dysfunction. PRES is classically suspected in patients with severe hypertension, renal failure, autoimmune disorders, eclampsia, or immunosuppressant medications. Frequent neurological evaluations and neuroimaging examinations by computed tomography or magnetic resonance imaging are required for both the diagnosis and assessment of the condition. Early detection of the disease is key for a rapid recovery and good prognosis.

Serum Neurofilament Light: a Potential Diagnostic and Prognostic Biomarker in Obstetric Posterior Reversible Encephalopathy Syndrome

Obstetric posterior reversible encephalopathy syndrome (PRES), caused by preeclampsia (PE) or eclampsia, is a clinical imaging syndrome and a critical maternal complication, with vasogenic edema in white matter as a typical imaging characteristic. Serum neurofilament light (NFL) is a marker of neuroaxonal injury. Therefore, we performed this study to explore the diagnostic and prognostic role of NFL in obstetric PRES. We used stored serum samples and clinical data obtained from 2148 PE or eclampsia patients from the Guangzhou Medical Centre for Critical Pregnant Women from January 2015 to January 2020. The serum NFL concentration was measured by Simoa assay. Patients without complete data and MRI examinations were excluded. All patients were grouped into the PRES and non-PRES groups based on the PRES diagnostic criteria. In total, 222 patients met the inclusion criteria and were grouped into the PRES (n = 123) and non-PRES (n = 99) groups. The NFL level was significantly higher in the PRES group than in the non-PRES group (p < 0.0001). The discriminatory accuracy of diagnostic panels (headaches + NFL, NFL) in receiver operating characteristic curve analysis (area under the curve) was 0.9338 and 0.7664. Importantly, the NFL level was significantly correlated with edema severity (Spearman's correlation, p < 0.0001), and a poorer pregnancy outcome was observed in the PRES group. In conclusion, an increased NFL level can add predictive value for diagnosing obstetric PRES, and its level is associated with both clinical severity and pregnancy outcome, suggesting that NFL could serve as a diagnostic and prognostic biomarker for obstetric PRES.

Neurology of Preeclampsia and Related Disorders: an Update in Neuro-obstetrics

PURPOSE OF REVIEW

Preeclampsia and related hypertensive disorders of pregnancy affect up to 10% of pregnancies. Neurological complications are common and neurologists often become involved in the care of obstetric patients with preeclampsia. Here, we review the definition(s), epidemiology, clinical features, and pathophysiology of preeclampsia, focusing on maternal neurological complications and headache as a common presenting symptom of preeclampsia.

RECENT FINDINGS

Neurological symptoms are early and disease-defining features of preeclampsia. Neurological complications of preeclampsia may include headaches, visual symptoms, cerebral edema, seizures, or acute cerebrovascular disorders such as intracerebral hemorrhage or reversible cerebral vasoconstriction syndrome. A history of migraine is an independent risk factor for vascular diseases during pregnancy, including preeclampsia and maternal stroke. The pathophysiology of both preeclampsia and migraine is complex, and the mechanisms linking the two are not fully understood. Overlapping clinical and pathophysiological features of migraine and preeclampsia include inflammation, vascular endothelial dysfunction, and changes in vasoreactivity. Neurological complications are recognized as a major contributor to maternal morbidity and mortality. Pregnant and postpartum women commonly present with headache, and red flags in the clinical history and examination should prompt urgent neuroimaging and laboratory evaluation. A focused headache history should be elicited from patients as part of routine obstetrical care to identify patients at an increased risk of preeclampsia and related hypertensive disorders of pregnancy. Collaborative models of care and scientific investigation in the emerging field of neuro-obstetrics have the common goal of reducing the risk of maternal neurological morbidity and mortality from preeclampsia.

Magnesium and Hypertension in Old Age

Hypertension is a complex condition in which various actors and mechanisms combine, resulting in cardiovascular and cerebrovascular complications that today represent the most frequent causes of mortality, morbidity, disability, and health expenses worldwide. In the last decades, there has been an exceptional amount of experimental, epidemiological, and clinical studies confirming a close relationship between magnesium deficit and high blood pressure. Multiple mechanisms may help to explain the bulk of evidence supporting a protective effect of magnesium against hypertension and its complications. Hypertension increases sharply with advancing age, hence older persons are those most affected by its negative consequences. They are also more frequently at risk of magnesium deficiency by multiple mechanisms, which may, at least in part, explain the higher frequency of hypertension and its long-term complications. The evidence for a favorable effect of magnesium on hypertension risk emphasizes the importance of broadly encouraging the intake of foods such as vegetables, nuts, whole cereals and legumes, optimal dietary sources of magnesium, avoiding processed food, which are very poor in magnesium and other fundamental nutrients, in order to prevent hypertension. In some cases, when diet is not enough to maintain an adequate magnesium status, magnesium supplementation may be of benefit and has been shown to be well tolerated.