Posterior reversible encephalopathy syndrome after solid organ transplantation

Posterior reversible leukoencephalopathy syndrome (PRES) after kidney transplantation: a case report

INTRODUCTION

Posterior reversible leukoencephalopathy syndrome (PRES) was first described by Hinchey in 1996. The syndrome is characterized by altered level of consciousness, headache, visual changes, and seizures associated with a vasogenic edema of the white matter that occurs predominantly in the occipital and parietal lobes. Imaging tests such as computed tomography (CT) and especially magnetic resonance imaging (MRI) support the diagnosis.

CASE REPORT

We report a case of a 48-year-old female patient who underwent a deceased donor kidney transplant and received tacrolimus as a part of the immunosuppressive regimen. Five weeks after transplantation she was admitted to the emergency due to sudden onset of confusion, disorientation, visual disturbances, and major headache. PRES was suspected and the diagnosis confirmed by brain MRI. Tacrolimus was withdrawn and rapid improvement of the neurological signs occurred leading to the conclusion that this drug triggered the syndrome.

CONCLUSION

PRES is an unusual complication after organ transplantation and should be considered in the appropriate clinical setting. Physicians must be aware of this condition in order to provide early detection and appropriate treatment since delay in removing the cause may lead to permanent sequelae.

Clinical and Imaging Findings in Childhood Posterior Reversible Encephalopathy Syndrome

OBJECTIVE

Posterior reversible encephalopathy syndrome (PRES) is characterized by typical radiologic findings in the posterior regions of the cerebral hemispheres and cerebellum. The symptoms include headache, nausea, vomiting, visual disturbances, focal neurologic deficits, and seizures. The aim of this study is to evaluate the clinical and radiological features of PRES in children and to emphasize the recognition of atypical features.

MATERIALS & METHODS

We retrospectively examined 23 children with PRES from Mar 2010-Apr 2015 in Inonu University Turgut Ozal Medical Center in Turkey. We compared the clinical features and cranial MRI findings between underlying diseases of PRES.

RESULTS

The most common precipitating factors were hypertension (78.2%) and medications, namely immunosuppressive and antineoplastic agents (60.8%). Manifestations included mental changes (100%), seizures (95.6%), headache (60.8%), and visual disturbances (21.7%) of mean 3.6 (range 1-10) days' duration. Cranial magnetic resonance imaging (MRI) showed bilateral occipital lesions in all patients, associated in 82.6% with less typical distribution of lesions in frontal, temporal or parietal lobes, cerebellum, corpus callosum, basal ganglia, thalamus, and brain stem. Frontal involvement was predominant, observed in 56.5% of patients. Clinical recovery was followed by radiologic resolution in all patients.

CONCLUSION

PRES is often unsuspected by the clinician, thus radiologists may be the first to suggest this diagnosis on an MRI obtained for seizures or encephalopathy. Atypical MRI finding is seen quite often. Rapid diagnosis and treatment are required to avoid a devastating outcome.

Posterior Reversible Encephalopathy Syndrome After Orthotopic Heart Transplantation: A Case Report

BACKGROUND Calcineurin inhibitor-induced posterior reversible encephalopathy syndrome (PRES) is well described in liver and kidney transplant patients, but there is a paucity of data in heart transplant patients. PRES syndrome in the setting of heart transplantation can occur as early as 5 days following transplantation. CASE REPORT A 32-year-old woman who had recently undergone orthotopic heart transplantation developed headaches, visual disturbances, and generalized tonic clonic seizures 5 days after initiating anti-rejection therapy (tacrolimus, mycophenolate, and prednisone). No focal neurological deficits were noted on physical exam. Multifocal subcortical fluid attenuation inversion recovery (FLAIR) hyperintensity signals and areas of diffusion restriction with postcontrast enhancement, diagnostic of PRES, were found on MRI brain. Her symptoms resolved 2 days after tacrolimus was switched to cyclosporine. A follow-up MRI after 6 weeks demonstrated complete resolution of areas of flair hyperintensity signal. She was sent home on a short course of seizure prophylaxis, which was discontinued after the resolution of radiological findings. She had no further episodes of seizures for 6 months following discontinuation of her anti-epileptic regimen. CONCLUSIONS Tacrolimus-induced PRES can occur as early as 5 days after orthotopic heart transplantation. Early recognition of symptoms and management can prevent permanent neurological sequelae.

Neurological Complications of Respiratory Disease

The respiratory and central nervous systems are intimately connected. Ventilatory control is strictly regulated by central mechanisms in a complex process that involves central and peripheral chemoreceptors, baroreceptors, the cardiovascular system, and specific areas of the brain responsible for autonomic control. Disorders of the lung and respiratory system can interfere with these mechanisms and temporarily or permanently disrupt this complex network resulting in mild to severe neurological sequelae. This article explores the wide variety of neurological problems resulting from respiratory dysfunction, with emphasis on its pathophysiology, clinical features, prognosis, and long-term outcome.

Posterior reversible encephalopathy syndrome

The posterior reversible encephalopathy syndrome (PRES) is a neurological disorder of (sub)acute onset characterized by varied neurological symptoms, which may include headache, impaired visual acuity or visual field deficits, disorders of consciousness, confusion, seizures, and focal neurological deficits. In a majority of patients the clinical presentation includes elevated arterial blood pressure up to hypertensive emergencies. Neuroimaging, in particular magnetic resonance imaging, frequently shows a distinctive parieto-occipital pattern with a symmetric distribution of changes reflecting vasogenic edema. PRES frequently develops in the context of cytotoxic medication, (pre)eclampsia, sepsis, renal disease or autoimmune disorders. The treatment is symptomatic and is determined by the underlying condition. The overall prognosis is favorable, since clinical symptoms as well as imaging lesions are reversible in most patients. However, neurological sequelae including long-term epilepsy may persist in individual cases.

Neurologic complications of transplantation

Major neurologic morbidity, such as seizures and encephalopathy, complicates 20-30% of organ and stem cell transplantation procedures. The majority of these disorders occur in the early posttransplant period, but recipients remain at risk for opportunistic infections and other nervous system disorders for many years. These long-term risks may be increasing as acute survival increases, and a greater number of "sicker" patients are exposed to long-term immunosuppression. Drug neurotoxicity accounts for a significant proportion of complications, with posterior reversible leukoencephalopathy syndrome, primarily associated with calcineurin inhibitors (i.e., cyclosporine and tacrolimus), being prominent as a cause of seizures and neurologic deficits. A thorough evaluation of any patient who develops neurologic symptoms after transplantation is mandatory, since reversible and treatable conditions could be found, and important prognostic information can be obtained.

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.

Reversible posterior leukoencephalopathy associated with chronic graft-versus-host disease: A case report

The present study describes the clinical manifestations, magnetic resonance imaging (MRI) features and treatments of a 22-year-old male patient diagnosed with reversible posterior leukoencephalopathy syndrome (RPLS) associated with graft-versus-host disease (GVHD) 7 months after a haploid hematopoietic stem cell transplantation. The patient was admitted to hospital after falling unconscious. Head MRI demonstrated abnormal signals in the bilateral, frontal, parietal, temporal and occipital lobes, consistent with reversible posterior leukoencephalopathy syndrome (RPLS). Based on a detailed diagnosis, the response to treatment and follow-up, it was concluded that RPLS was closely associated with chronic graft-versus-host disease in the patient. The present case report is described in order to increase the awareness of RPLS.

[Posterior reversible encephalopathy syndrome]

Posterior reversible encephalopathy syndrome refers to a neurological disorder characterized by headache, disorders of consciousness, visual disturbances, epileptic seizures, and subcortical vasogenic edema. About two thirds of patients develop neurological symptoms, which are associated with blood pressure fluctuations. One hypothesis is that hypertensive episodes cause autoregulatory failure, and values above the upper limit of cerebral autoregulation result in a breakthrough followed by hyperperfusion and blood-brain barrier dysfunction. In another hypothesis, endothelial dysfunction triggered by numerous factors including preeclampsia, immunosuppressive agents, chemotherapeutics, sepsis, or autoimmune disorders is thought to be the key pathomechanism. Endo- or exogenic toxic agents including pharmacological substances, cytokines, or bacterial toxins are supposed to trigger endothelial activation and dysfunction resulting in the release of vasoconstrictors, pro-inflammatory mediators, and vascular leakage. Diagnosis is usually based on clinical and neuroimaging findings that frequently show a bilateral, symmetric, and parietooccipital pattern. However, the diagnosis can often only be confirmed during the course of disease after excluding important differential diagnoses. Currently, there is no specific treatment available. Lowering of arterial blood pressure and eliminating the underlying cause usually leads to an improvement of clinical and neuroradiological findings. Admission to a critical care unit is required in about 40 % of patients due to complicating conditions including status epilepticus, cerebral vasoconstriction, ischemia, or intracerebral hemorrhage. Prognosis is favorable; in the majority of patients neurological deficits and imaging findings resolve completely.

Posterior reversible encephalopathy syndrome after pediatric heart transplantation: Increased risk for children with preexisting Glenn/Fontan physiology

Identification of risk factors for PRES after organ transplant can improve early detection and avoid permanent neurological injury. High calcineurin-inhibitor levels and hypertension are recognized risk factors for PRES in adult transplant recipients. Limited data exist regarding PRES after pediatric HTx, with studies limited to case reports. We performed a retrospective review of 128 pediatric HTx recipients to identify risk factors for PRES. Seven of 128 (5.5%) recipients developed PRES at a median of 10 days (5-57) after HTx. The median age of recipients with PRES was 10.0 yr (5.7-19.0), compared to 1.4 yr (0.0-19.8) for recipients without PRES (p = 0.010). Fewer than half of recipients with PRES had elevated post-transplant calcineurin-inhibitor levels (n = 3) and/or preceding severe hypertension (n = 3). Four of seven who developed PRES (57%) had pretransplant Glenn or Fontan physiology (G/F). G/F was a significant risk factor for PRES (RR 4.99, 95% CI: 1.19-21.0, p = 0.036). Two recipients (29%), both with severe PRES, had residual neurological symptoms. In summary, PRES occurred in 5.5% of pediatric HTx recipients and presented early after HTx. All recipients with PRES were > 5 yr. Patients with pretransplant G/F were at increased risk, a risks factor not previously described.

Calcineurin Inhibitors Associated Posterior Reversible Encephalopathy Syndrome in Solid Organ Transplantation: Report of 2 Cases and Literature Review

Posterior reversible encephalopathy syndrome (PRES) is a rare neurologic side effect of calcineurin inhibitors (CNIs) with poorly understood clinical features.We report cases of 2 patients with PRES developing after kidney transplantation and summarize PRES clinical features through a literature review.The 1st case was a 28-year-old man who received a kidney transplant from a deceased donor. Initial immunosuppressive therapy consisted of tacrolimus/mycophenolate mofetil/prednisolone. He developed headache and blurred vision with visual field loss15 days after transplantation and generalized seizures 4 days later. The 2nd case was a 34-year-old man who received a living kidney transplant. His initial immunosuppressive therapy comprised tacrolimus/mycophenolate mofetil/prednisolone. Two months after transplantation, he developed seizures. Both patients were diagnosed with PRES based on neurological symptoms and magnetic resonance imaging (MRI) findings; they recovered after switching from tacrolimus to either a cyclosporine or a lower tacrolimus dose. CNI-associated PRES is an acute neurological syndrome with seizures, encephalopathy, visual abnormalities, headache, focal neurological deficits, and nausea/vomiting. It is always accompanied by hypertension. A fluid-attenuated inversion recovery signal MRI scan typically shows reversible subcortical white matter changes in the posterior cerebral hemisphere that usually occur within the 1st month after transplantation. CNI-associated PRES has a generally favorable prognosis with early diagnosis and prompt treatment including alternating or discontinuing CNIs and blood pressure control.CNI-associated PRES should be considered in patients exhibiting acute neurological symptoms after transplantation. Early diagnosis and immediate treatment are critical for a favorable prognosis.

Posterior reversible encephalopathy syndrome after kidney transplantation in pediatric recipients: Two cases

PRES is a neuro-clinical and radiological syndrome that can result as a consequence of several different conditions including hypertension, fluid overload, and immunosuppressive treatment. Herein, we report two children who received kidney and combined liver-kidney transplantation as treatment for renal hypodysplasia associated with bilateral vesico-ureteral reflux and methylmalonic acidemia, respectively. Early after surgery (seven and 10 days), both patients presented with hypertension and seizures. The patients' immunosuppressive regimen included steroid and calcineurin inhibitors (tacrolimus and cyclosporine, respectively) and basiliximab and one with anti-IL2 receptor. In both cases, the imaging strongly supported the diagnosis of PRES. In details, the CT scan showed hypodensities in the posterior areas of the brain, and brain MRI demonstrated parieto-occipital alterations indicative of vasogenic edema. Treatment with calcineurin inhibitors was temporally discontinued and restarted at lower dosage; arterial hypertension was treated with Ca-channel blockers. Both children fully recovered without any neurological sequels. In conclusion, in children undergoing solid organ transplantation, who develop neurological symptoms PRES, should be carefully considered in the differential diagnosis and once the diagnosis is ruled in, we recommend strict arterial blood pressure control and adjustment or withholding of calcineurin inhibitor therapy should be considered based upon blood levels.

Posterior Reversible Encephalopathy Syndrome as an Overlooked Complication of Induced Hypertension for Cerebral Vasospasm

Background and Purpose—

Delayed cerebral ischemia associated with cerebral vasospasm is a common cause of secondary neurological decline after aneurysmal subarachnoid hemorrhage (SAH). Triple-H therapy, induced hypertension, hypervolemia, and hemodilution, is often used to treat cerebral vasospasm. However, hypertensive treatment may carry significant medical morbidity, including cardiopulmonary, renal, and intracranial complications. Posterior reversible encephalopathy syndrome (PRES) is a reversible intracranial complication that has rarely been reported in the setting of induced hypertension.

Methods—

We present an illustrative case of PRES in a patient with induced hypertension for SAH-related cerebral vasospasm and performed a systematic review. Furthermore, the electronic database MEDLINE was searched for additional data in published studies of PRES after induced hypertension.

Results—

Overall, 7 case reports presenting 10 patients who developed PRES secondary to induced hypertension were found. Eighty-two percent of the patients were women. In all cases, the clinical symptoms were attributed to cerebral vasospasm before the diagnosis of PRES. The time from onset of induced hypertension to the development of PRES was 7.8±3.8 days. After the diagnosis of PRES and careful taper down of the blood pressure, the neurological symptoms resolved almost completely within a few days in all patients.

Conclusions—

PRES in the setting of SAH is an overlooked complication of hypertensive therapy for the treatment of vasospasm. However, the diagnosis of this phenomenon is crucial given the necessity to reverse hypertensive therapy, which is contrary to the usual management of patients with vasospasm.

The Critically Ill Kidney Transplant Recipient: A Narrative Review

Kidney transplantation is the most common solid organ transplantation performed worldwide. Up to 6% of kidney transplant recipients experience a life-threatening complication that requires ICU admission, chiefly in the late posttransplantation period (≥ 6 months). Acute respiratory failure and septic shock are the main reasons for ICU admission. Cardiac pulmonary edema, bacterial pneumonia, acute graft pyelonephritis, and bloodstream infections account for the vast majority of diagnoses in the ICU. Pneumocystis jirovecii pneumonia is the most common opportunistic infection, and one-half of the patients so infected require mechanical ventilation. The incidence of cytomegalovirus visceral infections in the era of preemptive therapy has dramatically decreased. Drug-related neutropenia, sirolimus-related pneumonitis, and posterior reversible encephalopathy syndrome are among the most common immunosuppression-associated toxic effects. Importantly, the impact of critical illness on graft function is worrisome. Throughout the ICU stay, acute kidney injury is common, and about 40% of the recipients require renal replacement therapy. One-half of the patients are discharged alive and free from dialysis. Hospital mortality can reach 30% and correlates with acute illness severity and reason for ICU admission. Transplant characteristics are not predictors of short-term survival. Graft survival depends on pre-ICU graft function, disease severity, and renal toxicity of ICU investigations and treatments.

Posterior Reversible Encephalopathy Syndrome After Transplantation: a Review

Posterior reversible encephalopathy syndrome (PRES) is a rare neurological disease. Recently, an increase in the number of transplantations has led to more cases being associated with PRES than what was previously reported. Calcineurin inhibitors (CNIs) are major risk factors for PRES in posttransplantation patients. The mechanisms of the development of PRES remain to be unclear. The typical clinical symptoms of PRES include seizures, acute encephalopathy syndrome, and visual symptoms. The hyperintense signal on fluid-attenuated inversion recovery image is the characteristic of the imaging appearance in these patients. In addition, other abnormal signals distributed in multiple locations are also reported in some atypical cases. Unfortunately, PRES is often not recognized or diagnosed too late due to complicated differential diagnoses, such as ischemic stroke, progressive multifocal leukoencephalopathy, and neurodegenerative diseases. Thus, this review emphasizes the importance of considering the possibility of PRES when neurological disturbances appear after solid organ transplantation or hematopoietic cell transplantation. Moreover, this review demonstrates the molecular mechanisms of PRES associated with CNIs after transplantation, which aims to help clinicians further understand PRES in the transplantation era.

Posterior reversible encephalopathy syndrome in lung transplantation: 5 case reports

Posterior reversible encephalopathy syndrome (PRES) is a cliniconeuroradiologic entity characterized by typical neurologic symptoms with characteristic cerebral image alterations. It has been reported in solid organ transplantations, especially related to the use of calcineurin inhibitors. The incidence of PRES in lung transplantation is unknown and probably under-reported in the literature. Here we describe 5 cases of PRES after bilateral lung transplantation. One of the reported cases was the first in the literature in which the neurologic onset precluded the introduction of calcineurin inhibitor. Therefore, although calcineurin inhibitors are known to play an important role in the development of PRES in the setting of lung transplantation, other causes seems to be involved in the physiopathology of this syndrome.

Immunosuppression based on everolimus in liver transplant recipients with severe early post-transplantation neurotoxicity

The immunosuppressive management of liver transplant recipients suffering early calcineurin inhibitor-induced neurotoxicity is a challenge in daily clinical practice. We have assessed the use of everolimus as the main immunosuppressant in patients presenting severe neurotoxicity in the early post-transplantation period. From October 1988 to October 2012, 10 patients in our center received everolimus because of severe neurotoxicity in the 1st 3 months after transplantation. We analyzed several variables associated with this treatment, including patient characteristics, time from liver transplantation to conversion to everolimus, immunosuppression regimens before and after conversion, treatment efficacy, adverse events, and discontinuation after conversion. Median follow-up after conversion to everolimus was 27 months (range, 1-63 mo). Neurotoxic events were: akinetic mutism in 4 patients, repeated convulsions in 3, cerebrovascular accident in 1, Guillain-Barré syndrome in 1, and disabling tremor in 1. Treatment with calcineurin inhibitors was discontinued in all patients. Post-conversion regimens consisted of everolimus plus mycophenolate mofetil (MMF) plus steroids in 7 patients, everolimus plus MMF in 1, everolimus plus steroids in 1, and everolimus alone in 1. Liver function was maintained for ≥1 month in all patients except 1, who presented a severe rejection that was treated with steroid bolus and Neoral cyclosporine. Neurologic function was fully recovered in 8 patients. In 1 patient with akinetic mutism and another with convulsions, tacrolimus was reintroduced at 2 months and 1 month, respectively, after resolution of the neurotoxic event. Everolimus is feasible and effective as the main immunosuppressant in patients suffering severe neurotoxicity during the 1st 3 months after transplantation. It allows neurologic function to be recovered while maintaining adequate liver function.

PRES in Children Undergoing Hematopoietic Stem Cell or Solid Organ Transplantation

Posterior reversible encephalopathy syndrome (PRES) is a clinical neuroradiologic entity that is becoming increasingly well known and documented in pediatrics. It is characterized by a variable association of seizures, headache, vomiting, altered mental status, visual disturbances, and seizures, as well as imaging suggesting white-gray matter edema involving the posterior regions of the central nervous system in most cases. The pathophysiology of PRES remains unclear. Although PRES has been associated with a widespread range of clinical conditions, namely infections, adverse drug events, autoimmune diseases, and many others, its onset after hematopoietic stem cell and solid organ transplantation remains the most commonly reported. Historically, PRES has proved to be generally reversible and associated with good clinical outcomes; however, severe complications, sometimes life-threatening, can also occur. Most reported cases of childhood PRES after hematopoietic stem cell or solid organ transplantation have been case reports or series across a broad spectrum of different transplant settings, and no clear consensus exists regarding how best to manage the syndrome. Thus, in this article, we provide a comprehensive review of the pathophysiological, clinical, and diagnostic aspects of PRES in children, with a specific focus on the transplant scenario. Differential diagnoses with other neurologic complications after pediatric transplantation are reviewed, and crucial issues in the management of PRES and the development of future research are ultimately addressed.

Posterior reversible encephalopathy syndrome in end-stage kidney disease: not strictly posterior or reversible

Posterior reversible encephalopathy syndrome (PRES) is an uncommon clinico-radiological condition that can result in severe brain injury. The pathogenesis of cerebral vasogenic edema, the hallmark of PRES, is not fully understood. Despite its name, there is substantial heterogeneity both in terms of imaging findings and outcome. Relatively little is known about PRES in kidney disease despite the clustering of risk factors including hypertension, autoimmune disease and immunosuppression. In a retrospective observational study of incident end-stage kidney disease patients in Southwest Ireland over a ten year period, we discovered five cases of PRES representing an incidence of 0.84% in this patient population. These five cases highlight the variability in clinical presentation and the potentially life-threatening nature of this condition. We provide an in-depth review of the existing literature regarding PRES in terms of its pathogenesis and heterogeneity, as well as the experience of PRES in ESKD patients. PRES appears to be rare in the ESKD population but could be under-recognized. Marked hypertension is a cardinal risk factor in this population, associated with extracellular fluid volume expansion. Neuroimaging findings can be diverse involving both anterior and posterior circulation territories. Three of the five patients described had commenced haemodialysis within four weeks of their presentation. These patients may be particularly vulnerable to microvascular brain injury, which can be devastating. This emphasises the need for clinicians to pay meticulous attention to extracellular fluid volume control during this potentially hazardous period.

A unique case of rituximab-related posterior reversible encephalopathy syndrome in a heart transplant recipient with posttransplant lymphoproliferative disorder

Rituximab is commonly used as a first line therapy to treat posttransplant lymphoproliferative disorders (PTLDs). It has also proved useful in the management of refractory antibody mediated graft rejection. We report an unusual case in which a heart transplant recipient being treated with rituximab for PTLD developed altered mental status, hallucinations and visual symptoms and magnetic resonance imaging (MRI) findings of symmetrical enhancement suggestive of posterior reversible leukoencephalopathy syndrome (PRES). Resolution of these clinical symptoms and radiological findings after discontinuation of therapy confirmed the diagnosis. This is the first case of PRES seen due to rituximab in a heart transplant recipient. Another unique feature of the case is the development of PRES after second cycle of rituximab as compared to prior reports in nonheart transplant patients in which the syndrome developed after first dose administration. The objective of this case report is to increase the awareness of this rare entity amongst immunocompromised transplant patients.

Metabolische Störungen

Im folgenden Kapitel werden die verschiedenen metabolischen Störungen betrachtet. Zunächst wird auf die allgemeinen und spezifischen neurologischen Komplikationen bei Organtransplantation eingegangen. Dann geht es um die metabolischen Enzephalopathien: Störungen der Gehirntätigkeit bei angeborenen und erworbenen Stoffwechselerkrankungen im engeren Sinn, Elektrolytstörungen, Hypovitaminosen, zerebrale Folgen einzelner Organdysfunktionen, zerebrale Hypoxien, Endotheliopathien und Mitochondropathien. Anschließend werden das Alkoholdelir und die Wernicke-Enzephalopathie erörtert. Bei zahlreichen akuten Erkrankungen von Gehirn, Rückenmark und peripherem Nervensystem treten typische Störungen vegetativer Systeme auf, deren Erkennung und Therapie insbesondere bei Intensivpatienten eine vitale Bedeutung haben kann: die autonomen Störungen. Bei der zentralen pontinen Myelinolyse kommt es zu einer akuten, vorwiegend fokal-symmetrischen Demyelinisierung im Hirnparenchym. Auch Basalganglienerkrankungen können intensivmedizinisch relevant werden. Und schließlich wird die akute Stressreaktion betrachtet, die aufgrund der vielfältigen metabolischen und endokrinen Veränderungen bei kritischen Erkrankungen entsteht. Gerade das RCVS als neuere Krankheitsentität und wichtige Differenzialdiagnose zur Vaskulitis des ZNS verdient einen eigenen Platz, in diesem Unterkapitel werden ebenfalls verwandte Syndrome wie die hypertensive Enzephalopathie und das PRES abgehandelt.

Prolonged pentobarbital-induced coma for the treatment of severe seizures related to posterior reversible encephalopathy syndrome

In this report, we describe a case of posterior reversible encephalopathy syndrome in a female patient after deceased donor liver transplantation. She developed posterior reversible encephalopathy syndrome on postoperative day 3 and did not improve despite adjustments in immunosuppressive therapy. The patient had symptoms of severe brain edema requiring maximal therapy, which included cooling, mannitol, 3% saline, and a pentobarbital infusion. Attempts to lighten the level of sedation failed because of recurring intractable seizure activity. Reductions in therapeutic support were ultimately successful after 62 days of continuous pentobarbital therapy. The patient awoke neurologically intact and was discharged to a rehabilitation center in good condition.

A study on clinical and radiological features and outcome in patients with posterior reversible encephalopathy syndrome (PRES)

Posterior reversible encephalopathy syndrome (PRES) is characterized clinically by headaches, seizures, vomiting, nausea, visual abnormalities, and altered mental function and is often (but not invariably) accompanied by parieto-occipital imaging features. The aim of this study is to describe the clinical and radiological features and outcome following PRES in a paediatric cohort. From a retrospectively identified cohort, case records were studied to confirm a diagnosis of PRES. Neuroimaging was reviewed again to assign to recently described radiological subtypes parieto-occipital pattern, holohemispheric watershed pattern, dominant superior frontal sulcus pattern, and asymmetrical or partial expression of the three primary patterns (A/P). Patient outcome was measured by the modified Rankin scale (mRS) scores. Nine boys and three girls with mean age of 12 were identified. Hypertensive episodes (n = 11), tacrolimus toxicity (n = 4), and autoimmunity (n = 1) were identified as potential risk factors/etiologies. Their median mRS at the peak of illness was 2 (range 2-5); three children required intensive care support. After mean follow-up of 35 months (median 37 months; range 3-60 months), all patients improved significantly with mean mRS of 1 (median 1; range 0-1).

CONCLUSION

PRES is easily recognizable by the clinical and radiological features. Although severe at presentation, the outcome from this condition is favorable.

Blood-brain barrier breakdown in reduced uterine perfusion pressure: a possible model of posterior reversible encephalopathy syndrome

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a clinical entity characterized by headaches, altered mental status, seizures, and visual disturbances and is associated with white matter vasogenic edema. There are no experimental models to study PRES brain changes.

METHODS

Twenty-eight pregnant Wistar rats were divided into 4 groups of 7: (1) pregnant-control; (2) reduced uterine perfusion pressure (RUPP); (3) invasive blood pressure (IBP); and (4) reduced uterine perfusion pressure plus invasive blood pressure (RUPP-IBP). The RUPP and RUPP-IBP groups were submitted to a reduction of uterine perfusion pressure at pregnancy days 13 to 15. The invasive mean arterial pressure of the IBP and RUPP-IBP groups was measured on day 20. The blood-brain barriers (BBBs) of all groups were analyzed using 2% Evans Blue dye on day 21.

RESULTS

RUPP rats had higher blood pressures and increased BBB permeability to Evans Blue dye compared with the control animals. Brain staining occurred in 11 of 14 RUPP rats and in none of the control groups (P < .0001).

CONCLUSIONS

The physiopathology of PRES remains unclear. Here, we described the use of RUPP rats as a potential model to better comprehend this syndrome.

Plasma levels of S100B in preeclampsia and association with possible central nervous system effects

BACKGROUND

S100B is supposed to be a peripheral biomarker of central nervous system (CNS) injury. The purpose of this study was to compare levels of S100B in women with preeclampsia with levels in healthy pregnant control subjects and furthermore to analyze levels of S100B in relation to possible CNS effects.

METHODS

A cross-sectional case–control study in antenatal care centers in Uppsala, Sweden, was performed. Fifty-three women with preeclampsia and 58 healthy pregnant women were recruited at similar gestational length; women with preeclampsia were recruited at time of diagnosis, and control subjects were recruited during their routine visit to an antenatal clinic. Plasma samples were collected, and levels of S100B were analyzed with an enzyme-linked immunosorbent assay. Information about demographic and clinical characteristics, including symptoms related to CNS affection, was collected from the medical records. The main outcome measures were plasma levels of S100B and possible CNS effects.

RESULTS

Levels of S100B were significantly higher among women with preeclampsia than among control subjects (0.12 µg/L vs. 0.07 µg/L; P < 0.001). In preeclampsia, there was a significant association between high levels of S100B and visual disturbances (P < 0.05).

CONCLUSIONS

S100B is increased among women with preeclampsia, and high levels of S100B associate with visual disturbances, which might reflect CNS affection in women with preeclampsia.

Posterior reversible encephalopathy syndrome in a child with steroid-resistant nephrotic syndrome: a case report and review of literature

Posterior reversible encephalopathy syndrome (PRES) is a rare and serious syndrome of central nervous system that can develop in both adults and children. It is characterized by acute onset of headache, confusion, seizures or focal neurological deficits along with radiological findings of white matter abnormalities in the parietal and occipital lobes. In the past ten years, this syndrome has been described mainly in adults, rare in children. Here, we report a case of PRES presenting in a 12-year-old girl with steroid-resistant nephrotic syndrome. Her neurological symptom was rapidly recovered after control of hypertension without discontinuation of cyclosporine A.

Central nervous system syndromes in solid organ transplant recipients

Solid organ transplant recipients have a high incidence of central nervous system (CNS) complications, including both focal and diffuse neurologic deficits. In the immunocompromised host, the initial clinical evaluation must focus on both life-threatening CNS infections and vascular or anatomic lesions. The clinical signs and symptoms of CNS processes are modified by the immunosuppression required to prevent graft rejection. In this population, these etiologies often coexist with drug toxicities and metabolic abnormalities that complicate the development of a specific approach to clinical management. This review assesses the multiple risk factors for CNS processes in solid organ transplant recipients and establishes a timeline to assist in the evaluation and management of these complex patients.

Posterior reversible encephalopathy syndrome: differences between pregnant and non-pregnant patients

Posterior reversible encephalopathy syndrome (PRES) is a clinical-radiologic entity not yet understood, that presents with transient neurologic symptoms and particular radiological findings. Few papers show the differences between pregnant and non-pregnant patients. We review the cases of 38 women diagnosed with PRES, in order to find significant differences between pregnant (18) and non-pregnant (20) patients. We found differences among the age of patients (25.83 years old in pregnant and 29.31 years old in non pregnant; P=0.001); in the mean of highest systolic blood pressure, that was higher in non-pregnant group (185:162 mmHg; P=0.121); and in creatinine levels that was higher in non-pregnant group (3.47:1.04 mg/dL; P=0.001). To our knowledge, just a few papers analyzed whether PRES syndrome presented in the same way in pregnant and non-pregnant patients. The differences and the possible pathophisiology of this syndrome still remain enigmatic.

Alternative tacrolimus and sirolimus regimen associated with rapid resolution of posterior reversible encephalopathy syndrome after lung transplantation

BACKGROUND

Neurotoxicity is a significant complication of calcineurin inhibitor use, and posterior reversible encephalopathy syndrome has been reported. Limited data exist on the use of alternative immunosuppression regimens in the management of posterior reversible encephalopathy syndrome in transplant recipients.

METHODS

We present the immunosuppression management strategy of a girl who underwent bilateral lung transplantation for cystic fibrosis 6 months earlier, then suddenly developed a grand mal seizure due to posterior reversible encephalopathy syndrome diagnosed by magnetic resonance imaging of the brain. In an effort to reduce her tacrolimus dose, an alternative immunosuppressant regimen combining tacrolimus and sirolimus was used.

RESULTS

After the modification of her immunosuppressant regimen, there was rapid clinical improvement with no further seizures. Her brain findings had resolved on magnetic resonance imaging 2 months later. Over the next 6 months, allograft function remained stable and surveillance transbronchial biopsies found no allograft rejection on the combined sirolimus and tacrolimus therapy.

CONCLUSIONS

Tacrolimus-associated neurotoxicity resolved in a lung transplant recipient with a combined tacrolimus and sirolimus regimen. This combined therapy appears to be an effective alternative for lung transplant recipients that allow them to receive the benefits of both drugs but at lower doses, which reduces the risk for adverse effects.

Neurologic aspects of multiple organ transplantation

Complex multiorgan failure may require simultaneous transplantation of several organs, including heart-lung, kidney-pancreas, or multivisceral transplantation. Solid organ transplantation can also be combined with hematopoietic stem cell transplantation to modulate immunologic response to a solid organ allograft. Combined multiorgan transplantation may offer a lower rate of allograft rejection and lower immunosuppression needs. In recent years, intestinal and multivisceral transplantations became viable as a rescue treatment for patients with irreversible intestinal failure who can no longer tolerate total parenteral nutrition with 70% survival after 5 years which is comparable to other types of solid organ allografts. Post-transplant neurologic complications were reported in up to 86% of allograft recipients and greatly overlap in intestinal and multivisceral allograft recipients, without a significant effect on the outcome of transplantation. Other common organ combinations in multiorgan transplantation include kidney-pancreas, which is mostly used for patients with renal failure and uncontrolled diabetes, and heart-lung for patients with congenital heart disease and idiopathic pulmonary arterial hypertension. Kidney-pancreas transplantation frequently results in an improvement of diabetic complications, including diabetic neuropathy. Heart-lung allograft recipients have very similar clinical course and spectrum of neurologic complications to lung transplant recipients. At this time there are no reports of an increased risk of graft-versus-host disease with combined transplantation of solid organ allograft and hematopoietic stem cells. Chronic immunosuppression and complex toxic-metabolic disturbances after multiorgan transplantation create a permissive environment for development of a wide spectrum of neurologic complications which largely resemble complications after transplantations of individual components of complex multiorgan allografts.

Neurologic complications of pancreas and small bowel transplantation

In the past decade, substantial improvements in patient and graft survival for pancreas and small bowel transplants have been achieved. Despite this progress, many patients still develop neurologic complications in the course of their illness. Small bowel transplants produce more neurologic complications because of the complex metabolic environment in which the procedure is performed and because of the intense immune suppression necessitated by the greater immunogenicity of the intestinal mucosa. Pancreas transplants stabilize and/or improve the signs and symptoms of diabetic neuropathy over time. Because transplantation of the pancreas is often coupled with a kidney transplant and small intestine with liver, neurologic complications in these patients sometimes reflect problems involving the organ partner or both organs. The spectrum of neurologic complications for pancreas and small bowel transplant recipients is similar to other organ transplants but their frequency varies depending on the type of transplant performed.

Neurologic complications in renal transplantation

Neurologic complications following kidney transplant are more common than in the general population with the reported incidence around 10-21%. Need for multiple drugs, decreased cellular immunity, accelerated atherosclerotic disease, and frequency of metabolic abnormalities are the most common predisposing factors for neurologic abnormalities. Neurologic side-effects of calcineurin inhibitors range from mild tremors to paraplegia or posterior reversible encephalopathy syndrome (PRES) and are generally reversible by lowering the dose or complete discontinuation of the drug when possible. Clinical presentation of central nervous system infection in transplant recipients can be different from the normal population as the anti-inflammatory effects of immunosuppressive therapy may obscure signs of meningeal inflammation and changes in the level of consciousness may be subtle. Bacterial infections remain the most common infections but unusual pathogens figure prominently in the differential diagnosis. The most frequent malignancies of the brain are lymphomas and metastatic tumors which are for the most part, de novo malignancies from immunosuppression. Decreasing immunosuppression is almost always a part of treating malignancy. The prevalence of stroke is reported to be around 8% with age>40 years, diabetic nephropathy as the underlying cause of end-stage kidney disease, and peripheral vascular disease being the strongest predictors.

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.

Tacrolimus-related cerebral microbleeds after lung transplantation

Posterior reversible encephalopathy syndrome is a well-known complication of treatment by tacrolimus. We report 2 cases of lung transplant recipients treated with tacrolimus who developed cerebral microbleeds on T2∗-weighted sequences in the acute setting of posterior reversible encephalopathy syndrome. Cerebral microbleeds may be a marker of tacrolimus-induced vasculopathy that may be detected earlier by neuropsychological and magnetic resonance imaging monitoring in transplant recipients treated with tacrolimus.

Posterior reversible encephalopathy syndrome in pediatric patients undergoing treatment for hemophagocytic lymphohistiocytosis: clinical outcomes and putative risk factors

Background

Hemophagocytic lymphohistiocytosis (HLH) is a rare multiorgan disease of toxic immune activation caused by the interaction of cytotoxic T cells and innate immune cells and frequently involves the central nervous system (CNS). Posterior reversible encephalopathy syndrome (PRES) might develop during treatment with the HLH-2004 protocol from the Histiocyte Society. The aims of this study were to evaluate clinical outcomes and putative risk factors for prediction of PRES related to HLH.

Methods

We reviewed the medical records of 28 patients with HLH who were treated between April 2005 and April 2012. We compared various clinical and laboratory parameters in patients without or with PRES to evaluate putative risk factors related to development of PRES.

Results

Six (21.4%) of the patients experienced PRES during treatment with the HLH-2004 protocol. Clinical and laboratory manifestations were not different compared with other conditions causing PRES. The main mechanism of PRES may be related to the HLH-2004 protocol and a high pro-inflammatory state. Most patients recovered quickly from neurologic manifestations without significant long-term sequelae. Preceding hypertension, an increase in ferritin level >50% compared with 1 week before development of PRES and hyponatremia were statistically significant factors.

Conclusion

PRES is clinically reversible and has a favorable outcome in patients with HLH. Awareness of PRES and a differential diagnosis of other causes of neurologic complications, including CNS involvement of HLH, can help avoid unnecessary treatment or delayed management. Patients with preceding hypertension, hyponatremia, and rising ferritin levels during HLH treatment should be closely monitored for PRES.

Biotic acts of antibiotics

Biological functions of antibiotics are not limited to killing. The most likely function of antibiotics in natural microbial ecosystems is signaling. Does this signaling function of antibiotics also extend to the eukaryotic – in particular mammalian – cells? In this review, the host modulating properties of three classes of antibiotics (macrolides, tetracyclines, and β-lactams) will be briefly discussed. Antibiotics can be effective in treatment of a broad spectrum of diseases and pathological conditions other than those of infectious etiology and, in this capacity, may find widespread applications beyond the intended antimicrobial use. This use, however, should not compromise the primary function antibiotics are used for. The biological background for this inter-kingdom signaling is also discussed.

Toxic leukoencephalopathies

Leukoencephalopathy is a syndrome of neurologic deficits, including alteration of mental status, caused by pathologic changes in the cerebral white matter. The term, toxic leukoencephalopathy, encompasses a wide variety of exposures and clinical presentations. The diagnosis in these Frontiers in Clinical Neurotoxicology syndromes is made by careful attention to the history, clinical features, and radiologic findings. This article details three of the best-defined toxic leukoencephalopathies: delayed posthypoxic leukoencephalopathy, including delayed neurologic sequelae after carbon monoxide poisoning; heroin inhalation leukoencephalopathy; and posterior reversible encephalopathy syndrome.