Spectrum and Potential Pathogenesis of Reversible Posterior Leukoencephalopathy Syndrome

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.

Posterior Reversible Encephalopathy Syndrome due to High Dose Corticosteroids for an MS Relapse

Increased blood pressure is a known adverse effect associated with corticosteroids but little is published regarding the risk with the high doses used in multiple sclerosis (MS). A 53-year-old female with known relapsing remitting MS presented with a new brainstem relapse. Standard of care treatment for an acute MS relapse, 1250 mg of oral prednisone for 5 days, was initiated. She developed an occipital headache and dizziness and felt generally unwell. These symptoms persisted after treatment was complete. On presentation to medical attention, her blood pressure was 199/110 mmHg, although she had no history of hypertension. MRI changes were consistent with posterior reversible encephalopathy syndrome (PRES), demonstrating abnormal T2 signal in both thalami, the posterior occipital and posterior parietal white matter with mild sulcal effacement. As her pressure normalized with medication, her symptoms resolved and the MRI changes improved. No secondary cause of hypertension was found. This is the first reported case of PRES secondary to high dose corticosteroid use for an MS relapse without a history of hypertension and with no other secondary cause of hypertension identified. This rare complication should be considered in MS patients presenting with a headache or other neurological symptoms during treatment for a relapse.

Magnetic resonance imaging appearance of hypertensive encephalopathy in a dog

A 16-year-old female spayed English Staffordshire terrier was presented for evaluation of a 10-month history of intermittent myoclonic episodes, and a one weeks history of short episodes of altered mentation, ataxia and collapse. Magnetic resonance imaging identified subcortical oedema, predominately in the parietal and temporal lobes and multiple cerebral microbleeds.

Serum biochemistry, indirect blood pressure measurements and magnetic resonance imaging abnormalities were consistent with hypertensive encephalopathy secondary to chronic kidney disease.

Seizures in children treated for a primary brain tumor: risk factors, evaluation and management

ABSTRACT 

Seizures may be a presenting symptom of a brain tumor in childhood or can occur as a complication of treatment or subsequent effect occurring years after completion of therapy. Seizures create a number of therapeutic challenges and represent a significant comorbidity that results in decreased quality of life. Treatment options may be limited by interactions with chemotherapy and/or increased susceptibility to side effects. Moreover, seizures in this patient population may be less responsive to the traditional therapies typically effective for nontumor related epilepsy. While the pathophysiology of tumor-related epilepsy remains unclear, advances are being made in our understanding of the possible mechanisms involved. Newer anticonvulsants and improved diagnostic tools with refined surgical techniques show promise for future treatment approaches.

Blood-retina-barrier disruption accompanying blood-brain-barrier dysfunction in posterior reversible encephalopathy syndrome

Blood-brain-barrier dysfunction is well known to accompany hypertensive posterior reversible encephalopathy syndrome (PRES) and is considered as the culprit of vasogenic edema and cerebral hemorrhage observed as part of this syndrome. An 84-year-old female was admitted with a diagnosis of PRES in the setting of malignant hypertension. The clinical course was further complicated by ischemic stroke and seizures. Contrast enhanced fluid attenuated inversion recovery (FLAIR) studies revealed diffuse enhancement within the subarachnoid space extending to regions without evidence of cytotoxic or vasogenic edema. These findings suggestive of increased permeability were not only confined to the blood-brain-barrier, but also involved the blood-retina-barrier interface. Our observations suggest that pathologic conditions that disrupt the integrity of blood-brain-barrier might concomitantly affect retinal microcirculation, which highly resembles cerebral microcirculation both anatomically and functionally. Imaging modalities sensitive for detection of blood-brain-barrier dysfunction, such as contrast enhanced FLAIR, might be helpful in identifying these abnormalities.

Refractory intracranial hypertension in posterior reversible encephalopathy syndrome

INTRODUCTION

Posterior reversible encephalopathy syndrome (PRES) is a largely reversible disease with long-term favorable outcome. A minority of patients, however, may develop progressive cerebral edema and ischemia resulting in severe disability or death. We report a case of severe intracranial hypertension associated with PRES that was successfully treated according to intracranial pressure (ICP)- and cerebral perfusion pressure (CPP)-driven therapy.

METHODS

Case report.

RESULTS

A 42-year-old woman underwent bilateral lung transplantation for severe bronchiectasis. Her immunosuppressive regimen consisted of azathioprine, prednisone, and tacrolimus. She acutely developed an aggressive form of PRES that rapidly resulted in severe refractory intracranial hypertension despite discontinuation of potentially causative medications and adequate supportive therapy. Accordingly, second-tier therapies, including barbiturate infusion, were instituted and immunosuppression was switched to anti-thymocyte globulin followed by mycophenolate mofetil. Within 10 h of barbiturate administration, ICP dropped to 20 mmHg. Thiopental was administered for two days and then rapidly tapered because of severe urosepsis. Six months after discharge from the intensive care unit the patient returned to near-normal life, her only complaint being short-term amnesia.

CONCLUSIONS

The decision to undertake ICP monitoring in medical conditions in which no clear recommendations exist greatly relies on physicians' judgment. This case suggests that ICP monitoring may be considered in the setting of acute PRES among selected patients, when severe intracranial hypertension is suspected, provided that a multidisciplinary team of neurocritical care specialists is readily available.

Posterior reversible encephalopathy syndrome after depletive lumbar puncture: a case report

Introduction

Posterior reversible encephalopathy syndrome is a rare entity. Its pathophysiology is still poorly understood.

Case presentation

We report the case of a 69-year-old White European woman who presented complete and proportional right hemiplegia, confusion, deviation of her head and eyes to the right, cortical blindness, and generalized tonic-clonic seizure 12 hours following a depletive lumbar puncture. Emergency cerebral magnetic resonance imaging showed bioccipital and left-side basal ganglia hyperintensities in the fluid attenuated inversion recovery and the diffusion-weighted images suggesting a radiological diagnosis of posterior reversible encephalopathy syndrome.

Conclusions

The diagnosis is established on clinical and radiological signs. This is the first report of this kind in the literature. We present a case of posterior reversible encephalopathy syndrome after depletive lumbar puncture and we discuss the pathophysiology.

Posterior reversible encephalopathy syndrome resulting from repeat bortezomib usage

Bortezomib is a chemotherapeutic agent that acts via proteasome inhibition resulting in cellular apoptosis and inhibition of angiogenesis. Although widely accepted as treatment of multiple myeloma and non-Hodgkin's lymphoma, it has also been shown to be efficacious in a variety of solid tumours such as pancreatic and colonic. Posterior reversible encephalopathy syndrome (PRES) is a neuroradiological syndrome characterised by vasogenic oedema involving the postero-occipital cortical and subcortical white matter resulting in visual disturbances, seizures and altered mental status. Although in most cases PRES is reversible with removal of the provoking condition or drug, if not appropriately recognised and treated it may lead to permanent and life-threatening sequelae such as intracerebral haemorrhage and ischaemic infarction. We report a case of PRES associated with bortezomib therapy and contrast it with four other previously reported cases. Recognition of this potentially severe neurological complication is important with the increasingly widespread use of bortezomib.

Hypertensive encephalopathy and cerebral infarction

Introduction

Hypertensive encephalopathy is one cause of posterior reversible encephalopathy syndrome. Hypertensive encephalopathy and cerebral infarction have only been reported in a few individual case reports.

Case description

A 51-year-old woman presented with hypertensive encephalopathy. T2-weighted images from magnetic resonance imaging showed hyperintense lesions in both occipital and parietal lobes. Diffusion-weighted imaging showed that this represented cytotoxic oedema and perfusion magnetic resonance imaging revealed reduced blood volume and flow. The magnetic resonance imaging was repeated 5 months later and subtotal regression of theT2-hyperintensity had occurred. However, small bilateral infarcts were seen on T1-weighted images. Perfusion magnetic resonance imaging presented reduced blood volume and flow on the right side.

Discussion and evaluation

The patient in this report had posterior reversible encephalopathy syndrome caused by hypertensive encephalopathy. Magnetic resonance imaging of the brain showed bilateral cytotoxic oedema that partially resolved and resulted in small infarcts. The imaging findings are compatible with posterior reversible encephalopathy syndrome with subtotal resolution and infarct evolution.

Conclusion

The case report suggests that the presence of hypertensive encephalopathy and posterior reversible encephalopathy syndrome should alert clinicians and lead to prompt treatment in order to prevent cerebral damage.

Takayasu's arteritis and posterior reversible encephalopathy syndrome: a case-based review

Autoimmune vasculitides can have diverse neurological manifestations, including posterior reversible encephalopathy syndrome (PRES). Takayasu's arteritis (TA) is an uncommon vasculitis rarely associated with PRES. Common clinical features of TA include hypertension, audible arterial bruits, absence of peripheral pulses, claudication of the extremities, reduced blood pressure in one or both arms, and angiographic abnormalities. PRES has been mostly associated with severe hypertension, endothelial injury, and conditions such as renal disease, immunosuppressive medication use, and rheumatologic diseases. Headaches, seizures, and altered mental status are the main clinical features as well as characteristic findings in magnetic resonance imaging. TA frequently presents with hypertension and is associated with endothelial injury, making this entity an ideal setting for the development of PRES. We report the case of a 17-year-old female who presented to the emergency department with severe hypertension, headache, and seizures. Magnetic resonance imaging findings were suggestive of PRES. She had absent pulses in the right upper extremity, abdominal bruits, and angiographic findings included subclavian and renal artery stenoses. The diagnosis of TA was made, and she responded well to treatment. We found ten additional cases of TA and PRES in the literature. All patients were females under the age of 40, had renovascular hypertension, and presented with headaches and seizures. Current literature relevant to this rare association is presented and discussed.