Dramatic Amelioration in Serial Magnetic Resonance Imaging in an "Isolated Brainstem" Reversible Encephalopathy Syndrome Case

Posterior reversible encephalopathy syndrome (PRES) is characterized by transient vasogenic edema predominantly in supratentorial areas within the posterior circulation regions. Although PRES with only brainstem involvement is quite rare, accurate diagnosis is important because prompt antihypertensive therapy contributes to a favorable outcome. Herein, we report a case with isolated brainstem PRES showing dramatical improvement in an apparent diffusion coefficient (ADC) value of the lesion in magnetic resonance imaging (MRI) after clinical remission. The present case suggests the association between favorable clinical course and complete amelioration on MRI.

A Rare Case of Postoperative Encephalopathy in Twin

The clinical picture of encephalopathy invites a broad differential with multiple etiologies. It is with judicious history, hospital course, lab testing, and imaging that the ultimate cause is identified. We present a unique case of identical twins who share a similar clinical presentation of postoperative encephalopathy. The striking similarities in both twins suggest a genetic component requiring further research to identify patients who are genetically predisposed.

Improving diagnostic approaches to cerebrovascular disorders in patients with hypertensive encephalopathy

BACKGROUND

Modern research today proves an increase in the incidence of ischemic stroke. Risk factors for vascular disease have become more common among young people. Clinical studies have shown that hypertension, dyslipidemia, and diabetes are traditional risk factors among the elderly. The aim of the study was to improve diagnostic approaches to cerebrovascular disorders in patients with hypertensive encephalopathy (НE) by clarifying the development of pathogenesis mechanisms, based on a comprehensive clinical study.

MATERIALS AND METHODS

This qualitative study was carried by clinical and neurological examination; neuropsychological examination (Mini-Mental State Examination, abbreviated multifactorial personality questionnaire, Beck depression scale, Spielberger scale).

RESULTS

The study was examined 351 patients (150 men, 201 women) with НE in hypertension of 2 degrees. The clinical examination was performed according to a two-stage method, which involves the establishment or exclusion of symptomatic hypertension. The study did not include patients with secondary hypertension, diabetes mellitus, cardiac arrhythmias, and conduction disorders, heart failure who suffered from acute cerebrovascular accident and myocardial infarction.

CONCLUSION

The necessity of obligatory examination by a neurologist of patients with arterial hypertension for detection of manifestations of НE with the use of modern research methods, which allows to prevent damage to target organs, and first of all - brain damage, has been proved.

Hyperglycemia Followed by an Abrupt Decrease of Blood Glucose Is a Rare Cause of Posterior Reversible Encephalopathy Syndrome (PRES)

Introduction

Posterior Reversible Encephalopathic Syndrome (PRES) is a clinical syndrome of headache, confusion or decreased level of consciousness, visual changes, seizures and focal neurologic signs associated with characteristic neuroimaging findings of posterior cerebral white matter edema. In most cases, PRES is precipitated by sudden increase in blood pressure; however, in the case presented here, the etiology was different as it was secondary to extreme changes in glucose levels.

Case Presentation

A 49-year-old female with a past medical history of hypertension and diabetes mellitus, type 2 was brought to the emergency room with a chief complaint of visual changes for 1 hour in duration. She described that the visual changes, like blurred vision in both eyes, happened after an abrupt decrease of blood glucose (BG) from 700 to 75 mg/dl. This abrupt drop in BG led to PRES in this patient, which is an uncommon presentation. Magnetic resonance imaging (MRI) of the brain was obtained, which was consistent with demyelinating lesions present in bilateral occipital lobes, suggestive of PRES. Fortunately, the patient's symptoms improved after avoidance of further abrupt fluctuations in BG. PRES commonly resolves within days if diagnosed and treated early. Prompt management can reduce morbidity and mortality.

Conclusion

A diagnosis of PRES can be difficult, especially if it was caused by rare etiology. In this case we highlight the cause and explain the hypothesis behind it.

Circulating microRNAs May Serve as Biomarkers for Hypertensive Emergency End-Organ Injuries and Address Underlying Pathways in an Animal Model

There is an incomplete understanding of the underlying pathophysiology in hypertensive emergencies, where severely elevated blood pressure causes acute end-organ injuries, as opposed to the long-term manifestations of chronic hypertension. Furthermore, current biomarkers are unable to detect early end-organ injuries like hypertensive encephalopathy and renal thrombotic microangiopathy. We hypothesized that circulating microRNAs (c-miRs) could identify acute and chronic complications of severe hypertension, and that combinations of c-miRs could elucidate important pathways involved. We studied the diagnostic accuracy of 145 c-miRs in Dahl salt-sensitive rats fed either a low-salt (N = 20: 0.3% NaCl) or a high-salt (N = 60: 8% NaCl) diet. Subclinical hypertensive encephalopathy and thrombotic microangiopathy were diagnosed by histopathology. In addition, heart failure with preserved ejection fraction was evaluated with echocardiography and N-terminal pro-brain natriuretic peptide; and endothelial dysfunction was studied using acetylcholine-induced aorta ring relaxation. Systolic blood pressure increased severely in animals on a high-salt diet (high-salt 205 ± 20 mm Hg vs. low-salt 152 ± 18 mm Hg, p < 0.001). Partial least squares discriminant analysis revealed 68 c-miRs discriminating between animals with and without hypertensive emergency complications. Twenty-nine c-miRs were strongly associated with hypertensive encephalopathy, 24 c-miRs with thrombotic microangiopathy, 30 c-miRs with heart failure with preserved ejection fraction, and 28 c-miRs with endothelial dysfunction. Hypertensive encephalopathy, thrombotic microangiopathy and heart failure with preserved ejection fraction were associated with deviations in many of the same c-miRs, whereas endothelial dysfunction was associated with a different set of c-miRs. Several of these c-miRs demonstrated fair to good diagnostic accuracy for a composite outcome of hypertensive encephalopathy, thrombotic microangiopathy and heart failure with preserved ejection fraction in receiver-operating-curve analyses (area-under-curve 0.75–0.88). Target prediction revealed an enrichment of genes related to several pathways relevant for cardiovascular disease (e.g., mucin type O-glycan biosynthesis, MAPK, Wnt, Hippo, and TGF-beta signaling). C-miRs could potentially serve as biomarkers of severe hypertensive end-organ injuries and elucidate important pathways involved.

[Posterior reversible encephalopathy syndrome and arterial hypertension]

OBJECTIVE

To identify a correlation between systolicdiastolic blood pressure (BP) and severity of clinical/radiological presentations in patients with posterior reversible encephalopathy syndrome (PRES).

MATERIAL AND METHODS

Clinical and paraclinic data of patients with PRES hospitalized in the Republican Clinical Hospital, Kazan in 2010-2018 were analyzed. Nineteen patients were found, all of them were women, aged 18-67 years, mean age 33.50±15.03 years. Clinical and paraclinic data included anamnesis, neurological examination, neuroimaging, first measurements of systolic and diastolic BP after symptoms'onset.

RESULTS AND CONCLUSION

Diastolic BP values can be associated with the incidence of depression of consciousness, systolic BP values - with the number of damaged structures. In total, BP is the significant factor implemented in the presence of endothelial dysfunction that defines the severity of encephalopathy.

Posterior Reversible Encephalopathy Syndrome in Clinical Toxicology: A Systematic Review of Published Case Reports

Background: Posterior reversible encephalopathy syndrome (PRES) is a rare clinical and radiological entity characterized by a typical brain edema. Although several case reports have described PRES in a context of poisoning, to our knowledge, a comprehensive assessment has not been performed. The aim of this systematic review was to raise awareness on poisoning-specific PRES features and to encourage consistent and detailed reporting of substance abuse–and drug overdose–associated PRES.

Methods: Medline/PubMed, Web of Science, and PsycINFO were screened through May 31, 2019, to systematically identify case reports and case series describing PRES associated with poisoning (i.e., alcohol, drugs, illicit drugs, natural toxins, chemical substances) in accidental context, intentional overdose, and substance abuse. The methodological quality of eligible case reports/series was assessed. Patients and exposure characteristics were recorded; relevant toxicological, radiological, and clinical data were extracted.

Results: Forty-one case reports and one case series reporting 42 unique cases were included. The median time to PRES onset from the start of exposure was 3 days (IQR 2–10). Acute high blood pressure, visual disturbance, and seizure were reported in 70, 55, and 50% of patients, respectively. The initial clinical presentation was alertness disorders in 64% of patients. Nine patients (21%) required mechanical ventilation. One-third of patients had at least one risk factor for PRES such as chronic hypertension (17%) or acute/chronic kidney failure (24%). The main imaging pattern (67%) was the combination of classical parieto-occipital edema with another anatomical region (e.g., frontal, basal ganglia, posterior fossa involvement). Vasogenic edema was found in 86% of patients. Intracranial hemorrhage occurred in 14% of patients. Both brain infarction and reversible cerebral vasoconstriction syndrome were diagnosed in 5% of patients. Three patients (12%, 3/25) had non-reversible lesions on follow-up magnetic resonance imaging. The median time required to hospital discharge was 14 days (IQR 7–18). Mortality and neurological recurrence rate were null.

Conclusions: Comorbidities such as chronic hypertension and kidney failure were less frequent than in patients with other PRES etiologies. Imaging analysis did not highlight a specific pattern for poisoning-induced PRES. Although less described, PRES in the context of poisoning, which shares most of the clinical and radiological characteristics of other etiologies, is not to be ignored.

Posterior reversible encephalopathy syndrome in eclampsia

Posterior reversible encephalopathy syndrome is characterized by acute headache, visual impairment, seizures, and altered mental status; neuroimaging may show cerebral edema affecting the parietal and occipital lobes of the brain. The objective of this article is to review the current understanding of posterior reversible encephalopathy syndrome in eclampsia. Literature was searched from PubMed, Scopus, and Google Scholar databases. The search terms included "eclampsia", "eclampsia and posterior reversible encephalopathy syndrome", and "pregnancy and posterior reversible encephalopathy syndrome". We reviewed all published original articles with the search term "posterior reversible encephalopathy syndrome". Up to 100% of eclamptic patients may have reversible posterior leukoencephalopathy syndrome. Two putative mechanisms - "vasogenic" and "vasospasm" - are considered to be responsible. Cerebral edema and petechial cortical hemorrhages are common autopsy findings. Clinical and neuroimaging manifestations are reversible in the majority of patients. Prompt correction of increased blood pressure and treatment of seizures are the cornerstones of treatment. Magnesium sulfate is the drug of choice for seizures. Some survivors may have permanent vision loss and other disabling sequelae. In conclusion, posterior reversible encephalopathy is a devastating complication of eclampsia. Early recognition helps in preventing some of its devastating sequelae.

HYPERTENSIVE HEART DISEASE AND ENCEPHALOPATHY IN A CENTRAL BEARDED DRAGON (POGONA VITTICEPS) WITH SEVERE ATHEROSCLEROSIS AND FIRST-DEGREE ATRIOVENTRICULAR BLOCK

A 0.5 kg, 5-yr-old male bearded dragon (Pogona vitticeps) presented with a 2-mo history of lethargy, anorexia, and impaired locomotion. Upon physical examination, bradyarrhythmia (heart rate: 20 beats/min) and balance disorders were noted. Electrocardiography revealed a first-degree atrioventricular block (P-R interval: 360 ms). On echocardiography, all cardiac chambers were slightly above normal ranges. Complete blood count, blood biochemistry, and T4 were unremarkable except for mildly elevated aspartate aminotransferase. Adenovirus testing was negative by polymerase chain reaction. Following euthanasia, necropsy revealed marked thickening of the arterial trunks and histopathology confirmed multifocal atherosclerosis of efferent heart vessels, arteriosclerosis of cerebral arterioles, and multifocal spongiosis of brain tissue, more pronounced in the optic chiasma. Owing to its severity, atherosclerosis may have contributed to chronic arterial hypertension with damages to the heart, brain vessels, and brain tissue-optic chiasma.

Status epilepticus in black African patients with hypertensive encephalopathy: a rare entity that must not be underrated

The severity of a blood pressure spike is more closely associated with serious organ dysfunction, which can be life-threatening in the short term, than with the blood pressure level itself. A hypertensive emergency is defined as the presence of high blood pressure associated with acute organ dysfunction. The specific nature of high blood pressure in black patients may cause more frequent hypertensive emergencies. In this retrospective case study, we report our experience and highlight the specific prognosis for black African patients. We examined three patients, aged 27, 47, and 59 years, admitted to intensive care for a hypertensive emergency with neurological distress, and all in status epilepticus. Average blood pressure was 171 mm HG. Treatment included intubation, ventilation, and induction of a barbiturate coma, plus antihypertensive treatment. The outcome was favorable, with an average stay of 5 days. The frequency of hypertensive emergencies varies according to age, ethnic origin, and period studied. Black patients often suffer from more severe forms of high blood pressure, arising at an earlier age. Hypertensive encephalopathy can occur in patients with or without chronic hypertension. Without treatment, the encephalopathy induces a coma that can quickly become fatal. Its spontaneous course is catastrophic (10-20% survival at one year), but more favorable with adequate treatment (60-80% survival at five years).

[Case of posterior reversible encephalopathy syndrome caused by Fisher syndrome]

This report presents a case of a 71-year-old woman with Fisher syndrome who had posterior reversible encephalopathy syndrome (PRES) before the initiation of intravenous immunoglobulin (IVIg) treatment. She had symptoms of common cold 2 weeks before the onset of PRES. On the day of the onset, she began to stagger while walking. On day 2, she developed hypertension, vision impairment, and limb weakness and was admitted to the hospital. On day 3, she was provided steroid pulse therapy. On day 4, she developed convulsions and right imperfection single paralysis and was transferred to the our hospital. During the transfer, the patient was conscious. Her blood pressure was high at 198/107 mmHg. She had mild weakness in her limbs and face, light perception in both eyes, dilation of both pupils, total external ophthalmoplegia, no tendon reflexes, and limb and trunk ataxia. We diagnosed PRES because of the high signal intensities observed on T₂-weighted MRI on both sides of the parietal and occipital lobes. We also diagnosed Fisher syndrome because of a positive anti-GQ1b immunoglobulin G antibody test and albuminocytologic dissociation in the cerebrospinal fluid. PRES showed prompt improvement with antihypertensive therapy, whereas Fisher syndrome slowly improved over a course of 2 months. This case is the first report of PRES without IVIg suggesting that Fisher syndrome induces hypertension and causes PRES.

Hypertensive Encephalopathy: A Case of a Male Who Bit Off His Fingers

Although altered consciousness and other neurologic manifestations are frequently seen in hypertensive encephalopathy, behavioral and psychotic symptoms are rarely seen. We describe a patient with no previous psychiatric history who was admitted for hypertensive crisis. A few days after admission, his blood pressure remained uncontrolled and he started to exhibit episodes of confusion, agitation, and psychosis. During one particular episode, he overcame multiple staff members and physical restraints to bite off two of his fingers without any signs of pain. Brain computed tomography (CT) was notable for possible posterior cerebral and cerebellar edema. His confusion and agitation gradually resolved with successful blood pressure management. This is the first reported case of extreme, agitated behaviors and auditory hallucinations in a patient with hypertensive crisis.

Posterior reversible encephalopathy in the intensive care unit

Posterior reversible encephalopathy syndrome (PRES) is increasingly diagnosed in the emergency department, and medical and surgical intensive care units. PRES is characterized by acute onset of neurologic symptoms in the setting of blood pressure fluctuations, eclampsia, autoimmune disease, transplantation, renal failure, or exposure to immunosuppressive or cytotoxic drugs, triggers known to admit patients to the intensive care unit (ICU). Although the exact pathophysiology remains unknown, there is growing consensus that PRES results from endothelial dysfunction. Because of the heterogeneous nature of the disorder, it is probable that different mechanisms of endothelial injury are etiologically important in different clinical situations. The presence of bilateral vasogenic edema on brain imaging, particularly in parieto-occipital regions, is of great diagnostic utility but PRES remains a clinical diagnosis. Although largely reversible, PRES can result in irreversible neurologic injury and even death. The range of clinical and radiographic manifestations of the syndrome is probably broader than previously thought, and it is imperative that clinicians become familiar with the full spectrum of the disorder, as prompt recognition and elimination of an inciting factor improve outcome. PRES may be the most frequent toxic-metabolic encephalopathy seen in the ICU.

Duloxetine-related posterior reversible encephalopathy syndrome: A case report

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) has well-established links with several drugs. Whether a link also exists with serotonin-norepinephrine reuptake inhibitor such as duloxetine is unclear.

METHODS

We report on a patient who developed PRES with a coma and myoclonus related to hypertensive encephalopathy a few days after starting duloxetine treatment. Magnetic resonance imaging was performed and catecholamine metabolites assayed.

RESULTS

The patient achieved a full recovery after aggressive antihypertensive therapy and intravenous anticonvulsant therapy.

CONCLUSIONS

The clinical history, blood and urinary catecholamine and serotonin levels, and response to treatment strongly suggest that PRES was induced by duloxetine. Duloxetine should be added to the list of causes of PRES.

Predictors of poor outcome in patients with posterior reversible encephalopathy syndrome

PURPOSE

Posterior reversible encephalopathy syndrome (PRES) is an acute neurotoxic syndrome that, although characteristically reversible, can be fatal or result in long-term disability in a subset of patients. Our aim was to identify factors associated with poor discharge outcome in PRES patients.

MATERIALS AND METHODS

We retrospectively reviewed the clinical and radiological records of all patients with PRES admitted at our tertiary care medical center from 2007 to 2014. They were divided based their modified Rankin Score at discharge and compared for their baseline variables, clinical, laboratory and imaging features. Poor outcome was defined by a modified Rankin scale 2-6 and was subdivided based on the primary mechanism that led to poor outcome.

RESULTS

Out of 100 PRES subjects, 36% had poor discharge outcomes. Factors associated with poor outcomes on univariate analysis were history of diabetes mellitus, coma, high Charlson comorbidity index, post-transplantation, autoimmune condition, lack of systolic or diastolic hypertension, elevated blood urea nitrogen and involvement of the corpus callosum. On multivariate analysis, only prior diabetes mellitus odd ratio (OR) = 6.8 (95% CI 1.1-42.1, p = 0.04), corpus callosum involvement (OR = 11.7; 95% CI 2.4-57.4, p = 0.00) were associated with poor outcome. Poor outcome also correlated with increased length of hospital stay (OR = 7.9; 95% CI 1.3-49.7, p = 0.03).

CONCLUSION

Large prospective studies incorporating serial blood glucose values and advanced imaging studies are required to validate these findings.

Risk of Stroke After the International Classification of Diseases-Ninth Revision Discharge Code Diagnosis of Hypertensive Encephalopathy

BACKGROUND AND PURPOSE

Although chronic hypertension is a well-established risk factor for stroke, little is known about stroke risk after hypertensive encephalopathy (HE), when neurologic sequelae of hypertension become evident. Therefore, we evaluated the risk of stroke after a diagnosis of HE.

METHODS

We identified all patients discharged from California, New York, and Florida emergency departments and acute care hospitals between 2005 and 2012 with a primary International Classification of Diseases, Ninth Edition, Clinical Modification discharge diagnosis of HE (437.2). Patients discharged with a primary diagnosis of seizure (345.x) served as negative controls, whereas patients with a primary diagnosis of transient ischemic attack (435.x) were positive controls. Our primary outcome was the composite of subsequent ischemic stroke or intracerebral hemorrhage. Kaplan-Meier survival statistics were used to calculate cumulative outcome rates, and Cox proportional hazard analysis was used to examine the association between index disease types and outcomes while adjusting for vascular risk factors.

RESULTS

We identified 8233 patients with HE, 191 091 with seizure, and 308 680 with transient ischemic attack. The 1-year cumulative rate of ischemic stroke or intracerebral hemorrhage after HE was 4.90% (95% confidence interval [CI], 4.45-5.40) when compared with 0.92% (95% CI, 0.88-0.97) after seizure and 4.49% (95% CI, 4.42-4.57) after transient ischemic attack. The risk of intracerebral hemorrhage was significantly elevated in those with HE (hazard ratio, 2.0; 95% CI, 1.7-2.5) but not in those with transient ischemic attack (hazard ratio, 1.0; 95% CI, 0.9-1.1), when compared with seizure patients.

CONCLUSIONS

Patients discharged with a diagnosis of HE face a high risk of future cerebrovascular events, particularly intracerebral hemorrhage.

Rhazes and an Early Case With Possible Hypertensive or Reversible Encephalopathy

In one of Rhazes' medical treatises, Tales and Stories of Patients, descriptions, medical manifestations, and treatment approaches of 34 patients were mentioned. Among those, an epileptic patient with a florid face and congested veins was cured by performing venesection on his saphenous and basilic veins. Signs and symptoms of the case might correspond to hypertensive or reversible encephalopathy.

Discharge status and in-hospital mortality in posterior reversible encephalopathy syndrome

BACKGROUND

Posterior reversible encephalopathy syndrome is a serious and increasingly recognized disorder, but data from observational studies on outcome and mortality in posterior reversible encephalopathy syndrome (PRES) are scarce. We aimed to determine the frequency and associations of in-hospital death and discharge status in a large cohort of patients with PRES.

METHOD

We retrospectively reviewed the radiological report databases of our university hospitals between January 1999 and March 2011 for patients with PRES. Patients fulfilling the criteria for PRES after detailed investigation of clinical charts and imaging studies were included. Clinical charts, paraclinical and brain imaging data at onset as well as available data on in-hospital mortality and discharge status were analyzed.

RESULTS

A total of 103 patients were included. Five (4.8%) patients died during hospital stay, 27 (26.2%) remained hospitalized after discharge. In univariate analyses, significant differences were found between patients discharged home from hospital and patients referred to rehabilitation or who died in hospital for the following variables: severe edema (P = 0.013), etiology of PRES (P = 0.001), altered mental state at onset (P = 0.003), altered coagulation (P = 0.004), and length of hospital stay >30 days (P < 0.001).

CONCLUSION

Features of a severe course of PRES such as severe edema and altered mental state are significantly more frequent in patients who were referred to inpatient rehabilitation or died in hospital. Prospective studies are warranted to establish factors that are associated with unfavorable outcome in PRES.

Bilateral papillopathy as a presenting sign of pheochromocytoma associated with von Hippel-Lindau disease

A 7-year-old girl presented with decreased vision in both eyes for 1 month. Examination showed visual acuity of 20/50 and 20/60, no afferent pupillary defect, cecocentral scotomas, and bilateral optic disc edema with extensive peripapillary and macular exudates. Magnetic resonance imaging showed multiple cortical and subcortical white matter lesions. Both the laboratory workup and the systemic examination were unrevealing. However, on follow-up, the patient showed episodic elevations of blood pressure as high as 240/160. Further workup revealed elevated urine catecholamines and a right supra-adrenal mass proven to be a pheochromocytoma by histopathologic analysis. The paroxysmal hypertension resolved, and the visual acuity, visual fields, fundus exam, and neuroimaging improved. The patient was lost to follow-up until age 18 when she developed shortness of breath and was found to have multiple pulmonary metastases identified as pheochromocytoma by biopsy. Genetic testing identified a 3p25-26 (c.482 G>A) VHL gene chromosomal mutation consistent with von Hippel–Lindau disease genotype. Multiple peripheral retinal vascular dilations and small retinal capillary hemangioblastomas were also found. This case highlights the importance of recognizing the lability of blood pressure often seen with pheochromocytomas, which may mask the underlying cause of hypertensive papillopathy and retinopathy, a diagnosis of low clinical suspicion in the pediatric population. The case also underscores the importance of thorough systemic workup, including genotyping to detect conditions where pheochromocytoma may be the presenting sign of the disease, such as multiple endocrine neoplasia 2A and 2B, von Hippel–Lindau disease, von Recklinghausen disease, tuberous sclerosis, and Sturge–Weber syndrome.

Lithium toxicity and PRES: a novel association

We report two cases of posterior reversible encephalopathy syndrome (PRES) occurring in association with supra-therapeutic serum lithium levels. Although the neurologic manifestations of lithium toxicity are well known, this is, to our knowledge, the first report describing a link between lithium toxicity and PRES. We discuss the current understanding of the pathogenesis of PRES and suggest mechanisms by which lithium may play a role in its development.

Hypertension and hypertensive encephalopathy

The definition of hypertension has continuously evolved over the last 50 years. Hypertension is currently defined as a blood pressure greater than 140/90mmHg. One in every four people in the US has been diagnosed with hypertension. The prevalence of hypertension increases further with age, affecting 75% of people over the age of 70. Hypertension is by far the most common risk factor identified in stroke patients. Hypertension causes pathologic changes in the walls of small (diameter<300 microns) arteries and arterioles usually at short branches of major arteries, which may result in either ischemic stroke or intracerebral hemorrhage. Reduction of blood pressure with diuretics, β-blockers, calcium channel blockers, and angiotensin-converting enzyme (ACE) inhibitors have all been shown to markedly reduce the incidence of stroke. Hypertensive emergency is defined as a blood pressure greater than 180/120mmHg with end organ dysfunction, such as chest pain, shortness of breath, encephalopathy, or focal neurologic deficits. Hypertensive encephalopathy is believed to be caused by acute failure of cerebrovascular autoregulation. Hypertensive emergency is treated with intravenous antihypertensive agents to reduce blood pressure by 25% within the first hour. Selective inhibition of cerebrovascular blood vessel permeability for the treatment of hypertensive emergency is beginning early clinical trials.

Posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is a recently proposed cliniconeuroradiologic entity with several well-known causes, such as hypertensive encephalopathy, eclampsia, and the use of cytotoxic and immunosuppressive drugs, as well as some causes more recently described. PRES is characterized by neuroimaging findings of reversible vasogenic subcortical edema without infarction. The pathogenesis is incompletely understood. Two opposing hypotheses are commonly cited, but the issue is controversial: (1) the current more popular theory suggests that severe hypertension exceeds the limits of autoregulation, leading to breakthrough brain edema; (2) the earlier original theory suggests that hypertension leads to cerebral autoregulatory vasoconstriction, ischemia, and subsequent brain edema. The clinical syndrome of PRES typically involves headache, encephalopathy, visual symptoms, and seizures. The clinical presentation is often nonspecific, and therefore the diagnosis of PRES has come to increasingly rely on magnetic resonance imaging (MRI) abnormalities consistent with PRES with documented recovery clinically and on repeated neuroimaging. The diagnosis has important therapeutic and prognostic implications because the reversibility of the clinical and radiologic abnormalities is contingent on the prompt control of blood pressure and/or discontinuing the offending drug.

Hypertensive brainstem encephalopathy involving deep supratentorial regions: does only blood pressure matter?

We report on a 42-year-old female patient who presented with high arterial blood pressure of 245/150 mmHg and hypertensive brainstem encephalopathy that involved the brainstem and extensive supratentorial deep gray and white matter. The lesions were nearly completely resolved several days after stabilization of the arterial blood pressure. Normal diffusion-weighted imaging findings and high apparent diffusion coefficient values suggested that the main pathomechanism was vasogenic edema owing to severe hypertension. On the basis of a literature review, the absolute value of blood pressure or whether the patient can control his/her blood pressure seems not to be associated with the degree of the lesions evident on magnetic resonance imaging. It remains to be determined if the acceleration rate and the duration of elevated arterial blood pressure might play a key role in the development of the hypertensive encephalopathy pattern.

Clinical review: the management of hypertensive crises

Hypertension is an extremely common clinical problem, affecting approximately 50 million people in the USA and approximately 1 billion individuals worldwide. Approximately 1% of these patients will develop acute elevations in blood pressure at some point in their lifetime. A number of terms have been applied to severe hypertension, including hypertensive crises, emergencies, and urgencies. By definition, acute elevations in blood pressure that are associated with end-organ damage are called hypertensive crises. Immediate reduction in blood pressure is required only in patients with acute end-organ damage. This article reviews current concepts, and common misconceptions and pitfalls in the diagnosis and management of patients with acutely elevated blood pressure.