[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.

COVID-19-Associated Bifacial Weakness with Paresthesia Subtype of Guillain-Barré Syndrome

We report a case of bifacial weakness with paresthesia, a recognized Guillain-Barré syndrome subtype characterized by rapidly progressive facial weakness and paresthesia without ataxia or other cranial neuropathies, which was temporally associated with antecedent coronavirus 2019 (COVID-19). This case highlights a potentially novel but critically important neurologic association of the COVID-19 disease process. Herein, we detail the clinicoradiologic work-up and diagnosis, clinical course, and multidisciplinary medical management of this patient with COVID-19. This case is illustrative of the increasingly recognized but potentially underreported neurologic manifestations of COVID-19, which must be considered and further investigated in this pandemic disease.

Posterior reversible encephalopathy syndrome (PRES): presentation, diagnosis and treatment

Posterior reversible encephalopathy syndrome (PRES) is a neurological disorder which is characterised by variable symptoms, which include visual disturbances, headache, vomiting, seizures and altered consciousness. The exact pathophysiology of PRES has not been completely explained, but hypertension and endothelial injury seem to be almost always present. Vasoconstriction resulting in vasogenic and cytotoxic edema is suspected to be responsible for the clinical symptoms as well as the neuro-radiological presentation. On imaging studies, Symmetrical white matter abnormalities suggestive of edema are seen in the computer tomography (CT) and magnetic resonance imaging (MRI) scans, commonly but not exclusively in the posterior parieto-occipital regions of the cerebral hemispheres. The management is chiefly concerned with stabilization of the patient, adequate and prompt control of blood pressure, prevention of seizures and timely caesarean section in obstetric cases with pre-eclampsia/eclampsia. In conclusion, persistently elevated blood pressures remain the chief culprit for the clinical symptoms as well as the neurological deficits. Early diagnosis by diffusion weighted MRI scans, and differentiation from other causes of altered sensorium i.e. seizures, meningitis and psychosis, is extremely important to initiate treatment and prevent further complications. Although most cases resolve successfully and carry a favorable prognosis, patients with inadequate therapeutic support or delay in treatment may not project a positive outcome.

A novel heterozygous mutation in the HMBS gene in a patient with acute intermittent porphyria and posterior reversible encephalopathy syndrome

Acute intermittent porphyria (AIP) is a rare inherited disorder, which is caused by the partial deficiency of hydroxymethylbilane synthase (HMBS), an enzyme of the heme biosynthetic pathway. Abdominal pain, neuropsychiatric disturbance and neuropathy are the typical manifestations of the disease. Complications such as posterior reversible encephalopathy syndrome (PRES), a rare type of brain lesion present on MRI, are also observed in patients with AIP. The present study reports on the case of a 36‑year‑old Chinese female patient with AIP and PRES. Genomic DNA were obtained from peripheral blood leukocytes and genomic regions of the HMBS gene were amplified as 2 fragments, which together contained all the exons and flanking intronic regions. Sanger sequencing of the amplified DNA fragments from the patient and the patient's family revealed a novel frameshift deletion (c.405‑406delAA) in exon 8 of the HMBS gene. This mutation leads to a subsequent truncated protein (p.Glu135AspfsX74). The recombinant mutant protein had 62% activity relative to the wild‑type protein but similar thermostability. It was confirmed that this novel mutation was the cause of AIP. Accumulation of D‑aminolevulinic acid (ALA) due to HMBS dysfunction is a potential mechanism of PRES. The manifestation of PRES may be associated with ALA‑induced cytotoxicity and the destruction of the blood‑brain barrier. In summary, in the present study, a novel pathogenic HMBS mutation was identified, expanding on the molecular heterogeneity of AIP.

Posterior reversible encephalopathy syndrome: A rare neurotoxicity after capecitabine

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a condition characterized by seizures, headache, visual disturbances, paresis, nausea and altered mental status. Risk factors include hypertension, eclampsia/pre-eclampsia, infection/sepsis, transplantation (allograft, bone marrow and solid organ) and immunosuppression, especially in association with autoimmune disorders and use of cyclosporine or chemotherapy.

CASE REPORT

A few days after starting the first cycle of treatment with capecitabine, a 50-year-old female with metastatic breast cancer experienced serious adverse events consisting of severe hematological, gastrointestinal and neurological toxicity. A brain magnetic resonance imaging, performed because of the severe state of confusion of the patient, confirmed PRES.

MANAGEMENT AND OUTCOME

The patient was admitted to the hospital; capecitabine was stopped and treatment was started with antibiotics, growth factor therapy and blood and platelet transfusions. Her clinical conditions slowly improved and the PRES resolved. A dihydropyrimidine dehydrogenase deficiency was identified.

DISCUSSION

The patient had previously been treated with another fluoropyrimidine, 5-fluorouracil, but without toxicity. A literature search was performed, and only six cases of PRES associated with capecitabine were found. Our case suggests that capecitabine differs from 5-fluorouracil in its mechanism of action and that at least one of the metabolites of capecitabine has the ability to cross the blood-brain barrier, causing neurotoxicity. We believe that it is useful to test for dihydropyrimidine dehydrogenase deficiency before using fluoropyrimidines and would encourage the reporting of such cases of PRES to gain a better overall picture of its incidence in this setting.

NARANJO SCORE

7.

Clinical and MRI Features of Posterior Reversible Encephalopathy Syndrome With Atypical Regions: A Descriptive Study With a Large Sample Size

Background: Accurate diagnosis and timely treatment for posterior reversible encephalopathy syndrome (PRES) with atypical regions are very important in clinical practice. However, until now, little has been known about the clinical and MRI manifestations of this disease. Therefore, the aim of this study is to investigate the clinical and MRI features of PRES to promote clinical management and deepen our understanding of this disease. Materials and Methods: Data from six PRES patients with atypical regions were collected from our hospital. Data from another 550 cases were obtained by searching the PubMed, EMBASE and Web of Science databases with the keywords "posterior reversible encephalopathy syndrome" "PRES" "reversible posterior leukoencephalopathy" "RPLS" "hypertensive encephalopathy" "hyperperfusion encephalopathy" or "reversible posterior cerebral edema encephalopathy." The clinical and MRI features of these 556 cases were analyzed together. Results: A total of 305 patients were female, and 248 were male, with a median age of 34 years. The information on sex and age of three patients was not available. The most common symptom was headache (282/556, 50.7%), followed by altered mental status (243/556, 43.7%), seizures (233/556, 41.9%), visual disturbances (194/556, 34.9%), nausea/vomiting (130/556, 23.4%), and focal neurological deficits (101/556, 18.2%). Hypertension (425/556, 76.4%), renal diseases (152/556, 27.3%), immunosuppressant drugs (79/556, 14.2%), and chemotherapy/chemoradiotherapy (59/556, 10.6%) were the major predisposing factors. The atypical regions of the lesions were the cerebellum (331/556, 59.5%), basal ganglia (135/556, 24.3%), periventricular/deep white matter (125/556, 22.5%), pons (124/556, 22.3%), brainstem (115/556, 20.7%), thalamus (114/556, 20.5%), midbrain (48/556, 8.6%), spinal cord (33/556, 5.9%), and medulla (29/556, 5.2%). Additionally, the following typical regions were observed: occipital (278/556, 50.0%), parietal (234/556, 42.1%), frontal (150/556, 27.0%), and temporal (124/556, 22.3%) lobes. The major treatments were antihypertensives (358/515, 69.5%), antiepileptics/sedation (126/515, 24.5%), discontinuation/switching agents (67/515, 13.0%), and steroids (54/515, 10.5%). The median time of the clinical state improved and abnormal neuroimaging resolved is 2-3 weeks after appropriate treatment. Conclusion: The common symptoms of PRES with atypical regions include headaches, altered mental status, seizures, visual disturbances, nausea or vomiting, and focal neurological deficits. The frequent predisposing factors include hypertension, renal diseases, immunosuppressant drugs and chemotherapy/chemoradiotherapy. MRI features are mainly characterized by vasogenic edema in central zones always accompanied by typical regions. Most cases can be reversed in 2-3 weeks when promptly recognized and properly treated.

Clinical, Etiological and Imaging Profile of Posterior Reversible Encephalopathy Syndrome: A Prospective and Follow-Up Study

Background:

Although first described more than two decades ago, posterior reversible encephalopathy syndrome (PRES) continues to be enigmatic. We prospectively followed consecutive patients of PRES both clinically and radiologically for a better understanding of natural history, symptomatology, and prognosis of this not so uncommon entity.

Patients and Methods:

The current study included 22 consecutive patients of PRES who were followed both clinically as well as radiologically at a tertiary care institute in Northern India from December 2014 to June 2016.

Results:

Mean age was 30.68 ± 12.68 years. The most common symptoms included altered sensorium (77.3%), headache (72.7%), seizures (63.6%), vomiting (36.4%), and visual disturbances (22.7%). About 94.5% of patients had parieto-occipital signal changes on neuroimaging. Magnetic resonance imaging (MRI) (n = 20) revealed involvement of sites considered atypical for PRES in 95% (frontal [55%], temporal [40%], cerebellum [40%], basal ganglia [15%], deep white matter [10%] and brainstem [10%]). Diffusion restriction, haemorrhage, and contrast enhancement were seen in 30%, 22.2%, and 25% of patients. At 3 months follow-up, modified Rankin scale was 0 in 19 patients and 1 in 1 patient. Two (9.1%) patients died. Eight (36.4%) patients had eclampsia, 5 (22.7%) each had chronic kidney disease and essential hypertension whereas 2 (9.1%) each had immune-mediated disorders and drug-induced PRES. None of the clinical or imaging features predicted outcome in PRES.

Conclusion:

Atypical MRI presentations of PRES are common, and there is a need to keep a strong index of suspicion for the diagnosis of PRES. The prognosis of PRES is good, and most cases show excellent recovery, particularly if underlying etiology can be treated satisfactorily.

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: Clinical Features and Outcome

Background: Posterior reversible encephalopathy syndrome (PRES) is an acute neurotoxic syndrome that is characterized by a spectrum neurological and radiological feature from various risk factors. Common neurological symptoms includes headache, impairment in level of consciousness, seizures, visual disturbances, and focal neurological deficits. Common triggering factors include blood pressure fluctuations, renal failure, eclampsia, exposure to immunosuppressive or cytotoxic agents and autoimmune disorders. The classic radiographic findings include bilateral subcortical vasogenic edema predominantly affecting the parieto-occipital regions but atypical features include involvement of other regions, cortical involvement, restricted diffusion, hemorrhage, contrast enhancement. This review is aimed to summarize the updated knowledge on the typical and atypical clinical and imaging features, prognostic markers and identify gaps in literature for future research.

Methods: Systematic literature review using PUBMED search from 1990 to 2019 was performed using terms PRES was performed.

Results: While clinical and radiographic reversibility is common, long-standing morbidity and mortality can occur in severe forms. In patients with malignant forms of PRES, aggressive care has markedly reduced mortality and improved functional outcomes. Although seizures were common, epilepsy is rare. Various factors that have been associated with poor outcome include altered sensorium, hypertensive etiology, hyperglycemia, longer time to control the causative factor, elevated C reactive protein, coagulopathy, extensive cerebral edema, and hemorrhage on imaging.

Conclusion: Large prospective studies that accurately predict factors that are associated with poor outcomes, determine the pathophysiology, and targeted therapy are required.

Posterior Reversible Encephalopathy Syndrome and Reversible Cerebral Vasoconstriction Syndrome: Clinical and Radiological Considerations

Posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS) are relatively uncommon neurological disorders, but their detection has been increasing mainly due to clinical awareness and spreading of magnetic resonance imaging (MRI). Because these syndromes share some common clinical and radiologic features and occasionally occur in the same patient, misdiagnosis may occur. PRES is characterized by varied neurological symptoms including headache, impaired visual acuity or visual field deficit, confusion, disorders of consciousness, seizures, and motor deficits often associated to peculiar neuroradiological pattern even if uncommon localization and ischemic or hemorrhagic lesions were described. RCVS is a group of diseases typically associated with severe headaches and reversible segmental vasoconstriction of cerebral arteries, often complicated by ischemic or hemorrhagic stroke. Pathophysiological basis of PRES and RCVS are still debated but, because they share some risk factors and clinical features, a possible common origin has been supposed. Clinical course is usually self-limiting, but prognosis may fluctuate from complete recovery to death due to complications of ischemic stroke or intracranial hemorrhage. Neuroradiological techniques such as digital angiography and MRI are helpful in the diagnostic pathway and a possible prognostic role of MRI has been suggested. This review will serve to summarize clinical, neuroradiological features and controversies underlying both syndromes that may mislead the diagnostic pathway and their possible relationship with pathophysiology, clinical course, and prognosis.

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

PURPOSE

Posterior reversible encephalopathy syndrome (PRES), defined by its clinical and imaging manifestations, is a critical maternal complication. The specific pathophysiological mechanism of PRES has not been fully elucidated and remains controversial. Recently, several case studies reported that hypomagnesemia is present in the acute phase of PRES regardless of its etiology. Moreover, magnesium sulfate is a conventional treatment for preeclampsia (PE) and eclampsia; therefore, we hypothesized that hypomagnesemia might play an important role in the cascades involved in PRES in PE or eclampsia.

METHOD

We consecutively collected PE and eclampsia patients who were examined via magnetic resonance imaging (MRI) and tested for magnesium levels between January 2013 and January 2017. All patients were grouped into PRES and non-PRES groups based on MRI results. Demographic data, magnesium levels and imaging features were collected retrospectively.

RESULTS

A total of 72 patients met the inclusion criteria; these participants were sorted into PRES (n = 38) and non-PRES (n = 34) groups. Twenty-four patients (63%) in the PRES group and 2 patients (6%) in the non-PRES group presented hypomagnesemia. Moreover, magnesium levels were significantly lower in the PRES group during both the acute phase (p < 0.001) and the post-phase (p = 0.04) than in the non-PRES group. However, there was no correlation between magnesium levels and edema severity during the acute phase.

CONCLUSIONS

These results demonstrate that hypomagnesemia frequently occurs in the acute phase of obstetric PRES and suggest a potential relationship between them. Such a connection would support the application of magnesium sulfate in PE and eclampsia patients to prevent PRES. However, additional randomized trials are needed.

Childhood Posterior Reversible Encephalopathy Syndrome: Clinicoradiological Characteristics, Managements, and Outcome

Posterior reversible encephalopathy syndrome (PRES) is a novel clinicoradiological syndrome characterized by convulsions, headache, altered mentality, and impaired vision, which are usually accompanied by hypertension. As its nomination, PRES is usually diagnosed according to the presence of typical neuroimage showing vasogenic edema predominately involving the posterior brain area. With the widespread utilization of magnetic resonance imaging (MRI), PRES is becoming more perceptible in different medical fields. Compared to adult cases, childhood PRES seems to have a broader clinical and neuroradiological spectrum. PRES can be associated with various underlying comorbidities, medication use, and therapeutic modalities in children with diverse neurological manifestations. Moreover, pediatric patients with PRES have a more significant propensity for atypical MRI findings beyond the typically posterior cerebral areas. The knowledge of typical and atypical presentations in children is essential to avoid misdiagnosing or missing PRES, which is a potentially treatable entity. Early supportive care is the mainstay of treatment, with particular attention to the treatment of hypertension with rigorous attention to all body systems. Prompt identification and symptom-directed management are imperative to achieve a reversible prognosis in childhood PRES. Future studies specially designed for the child population are required to determine potential outcome predictors, and further, to develop novel strategies of neuroprotection in childhood PRES.

Childhood Posterior Reversible Encephalopathy Syndrome: Clinicoradiological Characteristics, Managements, and Outcome

Posterior reversible encephalopathy syndrome (PRES) is a novel clinicoradiological syndrome characterized by convulsions, headache, altered mentality, and impaired vision, which are usually accompanied by hypertension. As its nomination, PRES is usually diagnosed according to the presence of typical neuroimage showing vasogenic edema predominately involving the posterior brain area. With the widespread utilization of magnetic resonance imaging (MRI), PRES is becoming more perceptible in different medical fields. Compared to adult cases, childhood PRES seems to have a broader clinical and neuroradiological spectrum. PRES can be associated with various underlying comorbidities, medication use, and therapeutic modalities in children with diverse neurological manifestations. Moreover, pediatric patients with PRES have a more significant propensity for atypical MRI findings beyond the typically posterior cerebral areas. The knowledge of typical and atypical presentations in children is essential to avoid misdiagnosing or missing PRES, which is a potentially treatable entity. Early supportive care is the mainstay of treatment, with particular attention to the treatment of hypertension with rigorous attention to all body systems. Prompt identification and symptom-directed management are imperative to achieve a reversible prognosis in childhood PRES. Future studies specially designed for the child population are required to determine potential outcome predictors, and further, to develop novel strategies of neuroprotection in childhood PRES.

Blood-Brain Barrier Disruption as a Potential Target for Therapy in Posterior Reversible Encephalopathy Syndrome: Evidence From Multimodal MRI in Rats

Background: To explore blood-brain barrier disruption in hypertensive posterior reversible encephalopathy syndrome. Methods: The hypertension rat models were successfully established and scanned on 7T micro-MRI. MRI parameter maps including apparent diffusion coefficient, T1 value, and perfusion metrics such as cerebral blood volume, cerebral blood flow, mean transit time and time to peak maps, were calculated. Results: The ADC values of the experimental group were higher than those of the control group both in cortical (P < 0.01) and subcortical (P < 0.05) regions. Voxel-wise analysis of ADC maps localized vasogenic edema primarily to the posterior portion of the brain. The increase in cerebral blood volume and cerebral blood flow values were found in the cortical and subcortical regions of rats with acute hypertension. No correlation was found between perfusion metrics and mean arterial pressure. The Evans blue dye content was higher in the posterior brain region than the anterior one (P < 0.05). Conclusions: Cerebral vasogenic edema resulting from acute hypertension supports the hypothesis of posterior reversible encephalopathy syndrome as the result of blood-brain barrier disruption, which maybe the potential therapeutic target for intervention.

Analysis of Clinical Symptoms and Brain MRI of Heat Stroke: 2 Case Reports and a Literature Review

INTRODUCTION

Heat stroke is defined as high body temperature causing multiple organ failure, psychological change, seizure, and consciousness disturbance, which lead to its high mortality rate. However, the involvement of brain injury is rare, and heat-stroke has only been reported in a few case reports or case series. The purpose of this case study was to evaluate the clinical symptoms and radiological features of heat stroke.

METHODS

We reviewed our hospital records and previously published reports to find cases of heat stroke. We excluded those with unknown clinical features or radiological findings.

RESULTS

We retrieved 2 cases of heat stroke from our hospital, which presented as extensive lesions on brain imaging that led to disseminated intravascular coagulation and death within a few days. In 21 previously reported cases of heat stroke, similar brain lesions were noted. These were classified as infarction/posterior reversible encephalopathy syndrome (PRES)-like lesions. The patients who developed PRES-like lesions and survived often developed cerebellar sequelae.

CONCLUSION

The mechanism of heat stroke is presumed to be multifactorial. Ischemic-like lesions result from hypovolemia and unusual coagulation, whereas PRES-like lesions are caused by direct heat and vasogenic edema due to hypercytokinemia. We need to consider the above mentioned conditions when evaluating heat stroke.

New-onset seizure activity in a transplant patient on immunosuppressive therapy

The evaluation of new-onset seizure activity must raise a much broader differential than just epilepsy. This case study highlights that broad differential and identifies an important, but less common, cause of seizure activity in specific patient populations. Information is summarized from recent primary research, case series, literature reviews, and meta-analyses. In the appropriate clinical context, the diagnosis of posterior reversible encephalopathy syndrome (PRES) should be considered as a cause of seizures. Posterior reversible encephalopathy syndrome is a neurotoxic syndrome characterized by posterior cerebral edema on imaging and triggered by a variety of inciting or predisposing factors. This article reviews suggestions for the identification and management of PRES. Because of the myriad factors, nurse practitioners should be familiar with PRES and may encounter it through primary care, emergency or urgent care, hospitalist medicine, or a variety of specialty roles.

Porphyria-induced posterior reversible encephalopathy syndrome and central nervous system dysfunction

BACKGROUND AND AIM

An association between neuropsychiatric manifestations and neuroimaging suggestive of posterior reversible encephalopathy syndrome (PRES) during porphyric attacks has been described in numerous case reports. We aimed to systematically review clinical-radiological features and likely pathogenic mechanisms of PRES in patients with acute hepatic porphyrias (AHP) and porphyric attacks.

METHODS

PubMed, Scopus, Ovid MEDLINE, and Google Scholar were searched (July 30, 2019). We included articles describing patients with convincing evidence of an AHP, confirmed porphyric attacks, and PRES in neuroimaging.

RESULTS

Forty-three out of 269 articles were included, which reported on 46 patients. Thirty-nine (84.8%) patients were women. The median age was 24 ± 13.8 years. 52.2% had unspecified AHP, 41.3% acute intermittent porphyria, 4.3% hereditary coproporphyria, and 2.2% variegate porphyria. 70.2% had systemic arterial hypertension. Seizures, mental changes, arterial hypertension, and hyponatremia occurred more frequently than expected for porphyric attacks (p < .001). Seizures and hyponatremia were also more frequent than expected for PRES. The most common distributions of brain lesions were occipital (81.4%), parietal (65.1%), frontal (60.5%), subcortical (40%), and cortical (32.5%). Cerebral vasoconstriction was demonstrated in 41.7% of the patients who underwent angiography. 19.6% of the patients had ischemic lesions, and 4.3% developed long-term sequelae (cognitive decline and focal neurological deficits).

CONCLUSIONS

Brain edema, vasoconstriction, and ischemia in the context of PRES likely account for central nervous symptoms in some porphyric attacks.

Posterior reversible encephalopathy syndrome

PURPOSE OF REVIEW

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological syndrome characterized by acute cerebral endotheliopathy with consecutive disruption of the blood-brain barrier and vasogenic edema. Since its first description in 1996, PRES is increasingly recognized. However, many aspects of this syndrome with its wide spectrum of clinical and radiological features are still incompletely understood. In this review, possible pathophysiological mechanisms, approaches to diagnosis, recent study results on outcome, and future directions of research are described.

RECENT FINDINGS

Clinical manifestations of PRES include seizures, headache, visual disturbances, altered mental state, and more rarely hemiparesis or aphasia. Vasogenic edema predominantly occurs in the parieto-occipital region, but lesions affecting formerly called 'atypical' regions such as frontal lobe, cerebellum, or basal ganglia are common. If treated early and adequately, that is by removal of the underlying cause, PRES has a favorable prognosis, but neurological residual symptoms and even mortality can occur, particularly in patients with complications such as intracranial hemorrhage.

SUMMARY

In summary, validated diagnostic criteria and algorithms are warranted to standardize the diagnosis of PRES. This is essential for further research and future prospective studies that should investigate risk factors for unfavorable outcome and identify the roles of imaging features, clinical symptoms, and other biomarkers in predicting outcome.

Acute radiological pattern and outcome in posterior reversible encephalopathy syndrome patients

OBJECTIVE

Posterior reversible encephalopathy syndrome (PRES) is a neurological disorder of acute or subacute onset characterized by varied neurological symptoms including headache, impaired visual acuity or visual field deficits, confusion, disorders of consciousness, seizures, and motor neurological deficits. Even if recognition of severe forms of PRES has improved, mainly due to magnetic resonance imaging, pathogenesis is still unclear and management of these patients remains challenging. Moreover, prognosis is unpredictable varying from complete recovery to death and factors related to prognosis are still lacking. We studied early magnetic resonance imaging characteristics and their relationships with prognosis.

PATIENTS AND METHODS

We performed a retrospective analysis in patients with clinical and neuroradiological charateristics of PRES performing magnetic resonance of the brain within 2 days of symptoms onset.

RESULTS

After reviewing site database of magnetic resonance imaging and clinical records compatible with PRES, 157 patients were selected. After imaging reviewing, 25 patients with clinical and neuroradiological diagnosis of PRES were enrolled, 22 (88%) females. Mean age of enrolled patients at presentation was 44.4+18.4 years (range, 21-84 years). Patients were classified according to neuroradiological characteristics such as ischemic lesions, distribution and severity of edema, hemorrhage and contrast enhancement. In our group 23 patients (92%) showed an almost complete recovery but 2 patients (8%) died during hospitalization. Outcome was significantly related with hypointensity on ADC (p = 0.002) and CE (p < 0.001).

CONCLUSION

Early MR features may be helpful in suggesting prognosis. Moreover, neuroimaging at the early stage of PRES may give new insights in pathophysiological mechanisms underlying brain damage and neurological impairment.

Statin-Associated Necrotizing Autoimmune Myositis Complicated by an Uncommon Adverse Effect to Treatment

Statin-associated necrotizing autoimmune myositis (NAM) is an autoimmune condition characterized by severe acute-onset proximal muscle weakness, a very high creatinine kinase (CK) level, and prominent myofiber necrosis and minimal lymphocytic infiltration on muscle biopsy. Unlike self-limited statin myopathy, this condition usually requires aggressive immunomodulation therapy to assist recovery and prevent future disability. In this case report, we present a patient who developed progressive muscle weakness after taking atorvastatin for one year. At initial presentation, her CK level was 28,000 U/L. She was diagnosed with statin-associated NAM and started on high-dose intravenous solumedrol, mycophenolate, and intravenous immunoglobulin (IVIG) therapy. However, she subsequently developed acute bilateral vision loss and right side hemineglect; she was diagnosed with posterior reversible encephalopathy syndrome (PRES), thought to be a possible delayed adverse reaction to IVIG. IVIG was discontinued, and the patient was treated with supportive therapy. At six-month follow-up, she had significant improvement in muscle strength and vision.

[Differential diagnosis of strokes, the traps to avoid]

Strokes are a significant issue in geriatric medicine as more than half occur in patients over the age of 75. However, not all the symptoms of a focal neurological deficit in the elderly are indicative of a stroke. There are a number of differential diagnoses and only a detailed examination of the patient can enable an accurate diagnosis to be established. However, in no case must this delay the urgent treatment of the patient suspected of having a stroke.

Posterior Reversible Encephalopathy Syndrome Caused by Fioricet (Butalbital-Acetaminophen-Caffeine)

A common side effect of Fioricet (butalbital-acetaminophen-caffeine) is high blood pressure caused by the caffeine content. We report a case of a 54-year-old female who developed the worst headache of her life after taking 2 tablets of butalbital-acetaminophen-caffeine every six hours for three days before presenting to the emergency department, where her blood pressure was 178/87 mmHg. A brain MRI showed edema in the subcortical white matter of the right occipital lobe, right parietal lobe, and left occipital lobe. Posterior reversible encephalopathy syndrome (PRES) was diagnosed. The patient returned within the week with severe headaches, visual hallucinations, and a blood pressure of 150/80 mmHg. Repeat brain MRI showed slight improvement of edema. Her brain imaging studies completely normalized at 10 months after diagnosis. Although the patient received appropriate treatment, she was unable to make full recovery. Due to her inability to work and the constant pain, the patient continues to struggle with depression.

"CHOICES": An acronym to aid in delineating potential causes of non-metabolic, non-infectious acute toxic leukoencephalopathy

•

Recognition the etiologies of ATL is important due to its potentially reversible nature after treatment or removal of the toxin.

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“CHOICES” is useful to memorize etiologies associated with PVWM injury in non-metabolic and non-infectious ATL patients.

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Reduced diffusion is an early and important imaging finding to evaluate patients with non-metabolic and non-infectious ATL patients.

Purpose

To describe non-metabolic, non-infectious etiologies of acute toxic leukoencephalopathy (ATL) on DWI MRI, and provide a useful acronym to remember them.

Material and Methods

Our PACS archive was reviewed, yielding 185 patients with suspected ATL per MRI reports and clinical follow up; infectious or metabolic causes were excluded.

Result/Discussion

The 87 included non-infectious, non-metabolic ATL patients' etiologies are represented by the acronym 'CHOICES': chemotherapy ('C',n = 34); heroin-induced ('H',n = 6), opioid analogues ('O',n = 14); immunosuppressant ('I',n = 11) or imidazole (n = 2); cocaine ('C',n = 1); environmental or ethanol abuse ('E',n = 5), splenial lesions ('S',n = 9), and 'other' (n = 5).

Conclusion

The "CHOICES" acronym delineates various toxic etiologies of ATL.

Arginine Vasopressin and Posterior Reversible Encephalopathy Syndrome Pathophysiology: the Missing Link?

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological entity characterized by a typical brain edema. Its pathogenesis is still debated through hypoperfusion and hyperperfusion theories, which have many limitations. As PRES occurs almost exclusively in clinical situations with arginine vasopressin (AVP) hypersecretion, such as eclampsia and sepsis, we hypothesize that AVP plays a central pathophysiologic role. In this review, we discuss the genesis of PRES and its symptoms through this novel approach. We theorize that AVP axis stimulation precipitates PRES development through an increase in AVP secretion or AVP receptor density. Activation of vasopressin V_1a receptors leads to cerebral vasoconstriction, causing endothelial dysfunction and cerebral ischemia. This promotes cytotoxic edema through hydromineral transglial flux dysfunction and may increase endothelial permeability, leading to subsequent vasogenic brain edema. If our hypothesis is confirmed, it opens new perspectives for better patient monitoring and therapies targeting the AVP axis in PRES.

Transfusion-Transmitted Zika Virus Infection in Pregnant Mice Leads to Broad Tissue Tropism With Severe Placental Damage and Fetal Demise

Zika virus (ZIKV) infection during pregnancy can cause significant problems, particularly congenital Zika syndrome. Nevertheless, the potential deleterious consequences and associated mechanisms of transfusion-transmitted ZIKV infection on pregnant individuals and their fetuses and babies have not been investigated. Here we examined transmissibility of ZIKV through blood transfusion in ZIKV-susceptible pregnant A129 mice. Our data showed that transfused-transmitted ZIKV at the early infection stage led to significant viremia and broad tissue tropism in the pregnant recipient mice, which were not seen in those transfused with ZIKV-positive (ZIKV⁺) plasma at later infection stages. Importantly, pregnant mice transfused with early-stage, but not later stages, ZIKV⁺ plasma also exhibited severe placental infection with vascular damage and apoptosis, fetal infection and fetal damage, accompanied by fetal and pup death. Overall, this study suggests that transfusion-related transmission of ZIKV during initial stage of infection, which harbors high plasma viral titers, can cause serious adverse complications in the pregnant recipients and their fetuses and babies.

Association of Infants Exposed to Prenatal Zika Virus Infection With Their Clinical, Neurologic, and Developmental Status Evaluated via the General Movement Assessment Tool

IMPORTANCE

There is an urgent need to assess neurodevelopment in Zika virus (ZIKV)-exposed infants.

OBJECTIVES

To perform general movement assessment (GMA) at 9 to 20 weeks' postterm age and to evaluate whether the findings are associated with neurodevelopmental outcomes at age 12 months in infants prenatally exposed to acute maternal illness with rash in Brazil during the ZIKV outbreak and in age-matched controls.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study, infants prenatally exposed to acute maternal illness with rash were recruited at medical institutions in Rio de Janeiro and Belo Horizonte, Brazil, from February 1, 2016, to April 30, 2017, while infants without any exposure to maternal illness originated from the Graz University Audiovisual Research Database for the Interdisciplinary Analysis of Neurodevelopment. Participants were 444 infants, including 76 infants without congenital microcephaly, 35 infants with microcephaly, and 333 neurotypical children matched for sex, gestational age at birth, and age at GMA.

MAIN OUTCOMES AND MEASURES

General movement assessment performed at 9 to 20 weeks' postterm age, with negative predictive value, positive predictive value, sensitivity, and specificity generated, as well as clinical, neurologic, and developmental status (Bayley Scales of Infant and Toddler Development, Third Edition [Bayley-III] scores) at age 12 months. Motor Optimality Scores were generated based on the overall quality of the motor repertoire. Adverse outcomes were defined as a Bayley-III score less than 2 SD in at least 1 domain, a score less than 1 SD in at least 2 domains, and/or atypical neurologic findings.

RESULTS

A total of 444 infants were enrolled, including 111 children prenatally exposed to a maternal illness with rash and 333 children without any prenatal exposure to maternal illness (57.7% male and mean [SD] age, 14 [2] weeks for both groups); 82.1% (46 of 56) of ZIKV-exposed infants without congenital microcephaly were healthy at age 12 months. Forty-four of 46 infants were correctly identified by GMA at 3 months, with a negative predictive value of 94% (95% CI, 85%-97%). Seven of 10 ZIKV-exposed children without microcephaly with adverse neurodevelopmental outcomes were identified by GMA. The GMA positive predictive value was 78% (95% CI, 46%-94%), sensitivity was 70% (95% CI, 35%-93%), specificity was 96% (95% CI, 85%-99%), and accuracy was 91% (95% CI, 80%-97%). Children with microcephaly had bilateral spastic cerebral palsy; none had normal movements. The Motor Optimality Score differentiated outcomes: the median Motor Optimality Score was 23 (interquartile range [IQR], 21-26) in children with normal development, 12 (IQR, 8-19) in children with adverse outcomes, and 5 (IQR, 5-6) in children with microcephaly, a significant difference (P = .001).

CONCLUSIONS AND RELEVANCE

This study suggests that although a large proportion of ZIKV-exposed infants without microcephaly develop normally, many do not. The GMA should be incorporated into routine infant assessments to enable early entry into targeted treatment programs.

Posterior reversible encephalopathy syndrome (PRES) and infection: a systematic review of the literature

Posterior reversible encephalopathy syndrome (PRES) is an encephalopathy characterized by a rapid onset of symptoms including headache, seizures, confusion, blurred vision, and nausea associated with a typical magnetic resonance imaging appearance of reversible subcortical vasogenic edema prominent and not exclusive of parieto-occipital lobes. Vasogenic edema is caused by a blood-brain barrier leak induced by endothelial damage or a severe arterial hypertension exceeding the limits of cerebral blood flow autoregulation. Although the exact pathophysiological mechanism is still unclear, frequent conditions that may induce PRES include severe hypertension, eclampsia/pre-eclampsia, acute kidney diseases and failure, immunosuppressive therapy, solid organ, or bone marrow transplantation. Conversely to other conditions, which may induce PRES, the link between severe infection or sepsis and PRES, often associated with gram-positive bacteria, is still poorly understood and less well known. Clinicians from multiple disciplines, such as neurologists and internists, may encounter during their profession patients with severe infection or sepsis and should consider the possible association between PRES and these conditions. We systematically reviewed the literature about this association in order to provide a helpful clinical insight of such complex pathophysiological mechanism, highlighting the importance of recognizing PRES in such a complex clinical scenario.

Cerebrospinal Fluid in Posterior Reversible Encephalopathy Syndrome: Implications of Elevated Protein and Pleocytosis

Background and Purpose

Patients with posterior reversible encephalopathy syndrome (PRES) sometimes undergo analysis of cerebrospinal fluid (CSF) to exclude alternative diagnoses. This study's objectives were to describe the CSF characteristics in patients with PRES and to identify clinical and radiologic findings associated with distinct CSF abnormalities.

Methods

We identified a retrospective cohort of patients with PRES. We compared clinical and radiographic characteristics of those who did versus did not undergo lumbar puncture, described the observed range of CSF findings, and analyzed clinical and radiographic features associated with specific CSF abnormalities.

Results

A total of 188 patients were included. Patients with (n = 77) and without (n = 111) CSF analysis had similar clinical and radiographic characteristics. Cerebrospinal fluid protein was elevated in 46 (60%) of 77, with median CSF protein 53 mg/dL (upper limit of normal 45 mg/dL). Protein elevation was significantly associated with radiographic severity (P = .0058) but not with seizure, time from symptom onset, radiographic evidence of diffusion restriction, or contrast enhancement. Five (7%) patients had elevated CSF white blood cells, all of whom had infarction and/or hemorrhage on neuroimaging, and 4 of whom had eclampsia.

Conclusion

The CSF of most patients with PRES shows a mild protein elevation commensurate with radiographic severity. Cerebrospinal fluid pleocytosis may mark a distinct subtype of PRES with predisposition toward infarction and/or hemorrhage. These findings help clinicians interpret CSF findings in these patients and generate new hypotheses about the pathophysiology of this syndrome.

Diagnostic challenges in rapidly progressive dementia

INTRODUCTION

Rapidly progressive dementia is a syndrome caused by numerous disease entities. Accurate diagnosis is crucial as substantial proportion of these diseases is highly treatable. Others might implicate specific hygienic problems. Still, differential diagnosis remains challenging because of a huge overlap of clinical presentations. Areas covered: The paper reviews PubMed-listed research articles with a focus on diagnosis and treatment of diseases showing rapid cognitive decline such as inflammatory diseases, rapidly progressive neurodegenerative diseases, toxic-metabolic encephalopathies and prion diseases. The literature was interpreted in the light of experience in clinically differentiating rapid progressing dementia in the framework of Creutzfeldt-Jakob-Disease (CJD) surveillance activities. An overview of relevant differential diagnoses and diagnostic pitfalls as well as therapeutic protocols is presented. Expert commentary: Over the last years, more and more neurologic disorders causing cognitive symptoms, in particular various types of immune-mediated diseases have been discovered. To identify treatable conditions and to enhance knowledge of differential diagnosis and epidemiology, we suggest an extended diagnostic work up in cases with rapidly progressing dementia. Besides standard methods, this should include the search for neoplasia as well as atypical encephalitis. High-dose steroid therapy should be considered in certain clinical situations even when no evidence for inflammation is present.

Risk factors for poor outcome in posterior reversible encephalopathy syndrome: systematic review and meta-analysis

Background

The roles of clinical etiology and symptoms, imaging findings and biochemical parameters in predicting the prognosis of posterior reversible encephalopathy syndrome (PRES) have not been well-characterized. We perform a meta-analysis of all published studies to assess the value of various risk factors in predicting the prognosis of PRES.

Methods

Searches of the PubMed, EMBASE, Cochrane Library, and Web of Science databases were performed to identify the eligible studies. The odds ratios (ORs) with their corresponding 95% confidence interval (CI) for related risk factors were used to calculate the pooled estimates of the outcomes.

Results

Six studies with 448 cases were included in the meta-analysis. Hemorrhage was associated with high risk for poor outcome in patients with PRES. Toxemia of pregnancy (pre-eclampsia/eclampsia) was associated with improved outcome in PRES patients. Cytotoxic edema was noted to be related to poor outcome, but did not show statistical significance. The pooled OR for hemorrhage, pre-eclampsia/eclampsia, cytotoxic edema was 4.93 (95% CI: 3.94-6.17; P<0.00001), 0.24 (95% CI: 0.15-0.40; P<0.00001) and 2.59 (95% CI: 0.84-7.99; P=0.10), respectively.

Conclusions

PRES patients with hemorrhage or cytotoxic edema are likely to have poor outcomes. Pre-eclampsia/eclampsia is associated with reduced risk of poor outcome in patients with PRES.

New Developments in Hypertensive Encephalopathy

PURPOSE OF REVIEW

This review summarizes the latest science on hypertensive encephalopathy and posterior reversible encephalopathy syndrome (PRES). We review the epidemiology and pathophysiology of these overlapping syndromes and discuss best practices for diagnosis and management.

RECENT FINDINGS

Diagnosis of hypertensive encephalopathy largely relies on exclusion of other neurological emergencies. We review the extensive causes of PRES and its imaging characteristics. Management strategies have not changed substantially in the past decade, though newer calcium channel blockers simplify the approach to blood pressure reduction. While this alone may be sufficient for treatment of hypertensive encephalopathy in most cases, management of PRES also depends on modification of other precipitating factors. Hypertensive encephalopathy and PRES are overlapping disorders for which intensive blood pressure lowering is critical. Further research is indicated to both in diagnosis and additional management strategies for these critical conditions.

Cytotoxic Edema in Posterior Reversible Encephalopathy Syndrome: Correlation of MRI Features with Serum Albumin Levels

BACKGROUND AND PURPOSE

Posterior reversible encephalopathy syndrome is a clinicoradiologic entity with typical MR imaging showing predominant vasogenic and occasional cytotoxic edema. It is unclear whether MR imaging correlates with levels of serum albumin. We determined potential risk factors for development of cytotoxic edema in posterior reversible encephalopathy syndrome.

MATERIALS AND METHODS

Seventy-nine cases with typical clinical symptoms and characteristic neuroradiologic findings conformed to posterior reversible encephalopathy syndrome diagnostic criteria and were included in this study. FLAIR, DWI, and ADC maps were interpreted to evaluate the severity and type of edema. MR imaging was correlated with the levels of serum albumin, and cytotoxic edema was compared with the location and severity of brain edema.

RESULTS

Pure vasogenic edema was found in 53 cases (67.09%), and vasogenic edema complicated with cytotoxic components, in 26 patients (32.91%). There was no difference in serum albumin levels between patients with cytotoxic components and those with vasogenic edema (P = .983). There was a significant difference in the edema scale scores between patients with cytotoxic edema and those with vasogenic edema (P = .006). The percentage of cytotoxic edema located in the area with higher scale scores of edema was significantly larger than that in areas with lower scale scores of edema (P = .002).

CONCLUSIONS

Serum albumin may contribute to the development of edema in PRES but is not a decisive factor for edema type. Cytotoxic edema in posterior reversible encephalopathy syndrome is probably related to regional decreased perfusion and arteriolopathy. Further work should be undertaken to discover the pathophysiologic mechanisms involved.