Watershed imaging features and clinical vascular injury in cyclosporin A neurotoxicity

Posterior Reversible Encephalopathy Syndrome (PRES) and its relation with COPD

Introduction

and importance: PRES is a neurological disorder which is usually seen in adult females with symptoms like headache, altered mental status, seizures, impairment of vision. It is a radiographic diagnosis and can present with complications like status epilepticus, hemorrhagic and ischemic brain strokes.It can be associated with many clinical entities, COPD being one. Treatment is symptomatic.

Case presentation

We present a case of a 68 years female, presenting with clinical pictures of PRES in an episode of Acute Exacerbation of COPD, who has been diagnosed with PRES based on her CT head and MRI head findings. Treated by treating the infection and other symptomatic measures.

Clinical discussion

Our case had similar association with COPD as mentioned in few other articles.

Conclusion

Although rare, PRES is sometimes associated with exacerbation of COPD, and thus should not be ignored.

Current perspectives on neuroimaging techniques used to identify stroke mimics in clinical practice

INTRODUCTION

Urgent clinical assessment and brain imaging are essential for differentiating stroke mimics from stroke and to avoid unnecessary initiation of reperfusion and other therapies in stroke mimic patients.

AREAS COVERED

In this article, the authors will review acute stroke imaging and then the imaging patterns of the most common stroke mimics. The authors have focused our review on brain CT scan, and more specifically CT perfusion, as this is the most commonly available and emerging tool in emergency settings. The authors also provide information on acute brain MRI and MR perfusion.

EXPERT OPINION

Imaging can contribute to the detection and diagnosis of acute stroke mimics. Knowledge of imaging findings in different stroke mimics can help distinguish these from patients with stroke who require timely reperfusion therapy. CT and MRI perfusion and diffusion-weighted imaging (DWI) MRI are useful imaging modalities for the assessment of acute stroke patients as they provide more accurate information than plain CT scan. Some of these modalities should be available in the emergency setting. The authors recommended CT perfusion as a useful tool for stroke management and differentiation with stroke mimics.

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.

Fishing in muddy waters- co-existing dual intracranial pathology in PRES: A case series and review of literature

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state often characterized by altered mental state and is seen in various clinical settings. Although it is often reversible, it may result in long term sequelae. The typical and atypical neuroimaging findings seen in PRES have been previously well-described in the literature. However, the presence of other co-existing intracranial lesions along with PRES can occasionally confound the imaging findings and poses a diagnostic challenge. Herein, the authors report four cases of PRES with etiologically different co-existing intracranial lesions confounding the clinical and imaging manifestations. When presented with atypical imaging findings in PRES, the possibility of a co-existing intracranial pathology with superimposed imaging findings should be considered.

Predictors of intensive care unit utilization in patients with posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is an acute neurological syndrome that requires prompt, aggressive management to improve outcomes. Our aim was to identify factors that would necessitate care in the intensive care unit (ICU) in patients with PRES and the outcomes on discharge following ICU stay. We retrospectively reviewed the medical records and radiological data of adult PRES patients admitted to our tertiary care medical center. We dichotomized them into two groups based on their need for ICU care and compared their clinical, laboratory, imaging characteristics and discharge outcomes. Outcomes were defined using the modified Rankin Score (mRS) and Glasgow Outcome Score (GOS) on discharge. Out of 100 patients, 67 % required admission to the ICU. On univariate analysis, factors associated with ICU admission were atrial fibrillation (19.4 vs 0 %; p ≤ 0.05), encephalopathy from PRES (89.6 vs 66.7 %; p < 0.05), low Glasgow Coma Score (GCS) (11 ± 4 vs 14 ± 2; p = 0.01) and cortical involvement on imaging (89.6 vs 72.7 %, p = 0.03). On multivariate logistic regression analysis, encephalopathy (odds ratio 10.22; 95 % CI (1.14-91.55; p = 0.04) was the sole predictor of ICU utilization. This correlated with a GCS <12 (odds ratio 5.53; 95 % CI (1.05-29.22; p = 0.04). Despite worse functional outcomes following ICU care based on mRS (2.3 ± 2.1 vs 1.3 ± 1.4, p = 0.02) and GOS (3.9 ± 1.3 vs 4.6 ± 0.7, p ≤ 0.05), only a borderline increase in mortality was observed (10.4 vs 0 %, p = 0.05). The presence of PRES-related encephalopathy might aid in prompt identification of patients who require ICU care.

Posterior Reversible Encephalopathy Syndrome: Local Experience From Saudi Arabia

OBJECTIVES

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological syndrome characterized by headache, altered mental status, seizures, or loss of vision. In this study, we report the largest series of PRES coming from Saudi Arabia and explore the etiology, clinical presentation, and outcome. We also report new imaging findings associated with this condition.

METHODS

We performed a retrospective study of all cases of PRES admitted to King Abdulaziz Medical City, Jeddah, Saudi Arabia, between the years 2005 and 2015. A neurologist reviewed all charts and analyzed the clinical presentations, etiological factors, and outcomes, and a neuroradiologist reviewed the imaging studies. Only patients with clinical and imaging features consistent with PRES were included in the study.

RESULTS

We collected 31 patients who had clinical and radiological features consistent with PRES. Females were more affected than males (18 females and 13 males), and patients' age ranged from 6 to 95 years, with a mean of 38.3 years. Patients were treated by removing the precipitating causes and treating the underlying conditions. Resolution of neurologic signs occurred within 2 to 3 weeks in all patients.

CONCLUSION

In our opinion, PRES itself is usually a benign condition with complete recovery if the condition is recognized early and managed appropriately. Although clinical signs are nonspecific, the constellation of symptoms including headache, visual problems, seizures, and altered level of consciousness should suggest the possibility of PRES, especially in high-risk group. Abnormalities on magnetic resonance imaging are often characteristic and may be the first clue to the diagnosis.

Predictors of seizures in patients with posterior reversible encephalopathy syndrome

PURPOSE

Although seizures are common in patients with posterior reversible encephalopathy syndrome (PRES), epilepsy is rare. Our objective was to identify predictors and impact of seizures in patients with PRES.

METHODS

A retrospective review of the clinical and radiological parameters of all patients diagnosed with PRES from 2007 to 2014 was performed. Patients were divided into two groups based on the occurrence of PRES-related seizures at presentation or during their hospital course. Univariate and multivariate analyses were performed to determine factors associated with the occurrence of PRES-related seizures.

RESULTS

Of 100 patients, 70% experienced at least one seizure from PRES. On univariate analysis, the factors associated with seizures were the following: high Charlson comorbidity index (4.16±2.89 vs. 2.87±2.20, p=0.03), systemic malignancy (41.4% vs. 16.7%, p=0.02), occipital lobe involvement (97.1% vs. 83.3%, p=0.02), more lobes involved (4.6±1.48 vs. 3.9±1.32, p=0.03) but less likely in patients with visual disturbances (15.7% vs. 46.7%, p=0.005), and facial droop (12.9% vs. 16.7%, p=0.002). On multivariate analysis, only occipital lobe involvement was significantly (odds ratio: 9.63, 95% CI: 1.45-64.10, p=0.02) associated with the occurrence of PRES-related seizures. Despite the occurrence of seizures, they were less likely to require a nursing home placement upon hospital discharge (odds ratio: 0.17, 95% CI: 0.03-0.91, p=0.04).

CONCLUSION

We conclude that seizures are common in patients with occipital lobe involvement from PRES.

Predictors of poor outcome in patients with posterior reversible encephalopathy syndrome

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Childhood posterior reversible encephalopathy syndrome: Magnetic resonance imaging findings with emphasis on increased leptomeningeal FLAIR signal

PURPOSE

Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiologic syndrome characterized clinically by headache, seizures, and altered sensorium and radiological changes which are usually reversible. The purpose of this study was to describe the spectrum of magnetic resonance imaging (MRI) findings in childhood PRES, to determine the common etiologies for childhood PRES, and to have an insight into the pathophysiology of PRES.

METHODS

The MRI results of 20 clinically diagnosed cases of PRES between July 2011 and June 2013 were reviewed. The final diagnosis of PRES was based on the clinical presentation and the MRI features at the time of presentation, which resolved on the follow-up imaging. The medical records of the patients were reviewed to determine the underlying medical disease.

RESULTS

Eight out of the 20 patients included in the study were on cyclosporine or tacrolimus based immunosuppressant therapy for kidney transplant. Four patients had severe hypertension at presentation. The most common MRI finding was high T2-fluid-attenuated inversion recovery (FLAIR) signal in the cortex and subcortical white matter of both cerebral hemispheres, particularly in the parietal and occipital lobes (n=16). The second most common MRI finding was increased leptomeningeal FLAIR signal (n=7). Out of seven patients with leptomeningeal signal, five demonstrated leptomeningeal enhancement as well. Four out of these seven patients had no other parenchymal findings.

CONCLUSION

Childhood PRES is commonly seen in the setting of immunosuppressant therapy for kidney transplant, severe hypertension and cancer treatment. There was high incidence of increased leptomeningeal FLAIR signal and leptomeningeal enhancement in our study. It supports the current theory of endothelial injury with increased microvascular permeability as the potential pathophysiology of PRES. Also, absence of elevated blood pressure in majority of the patients in our study supports the theory of direct endothelial injury by some agents leading to vasogenic edema.

Etiologic Subtypes of Watershed Infarcts

BACKGROUND

Two types of watershed infarcts (WI) are recognized. Internal WI are usually attributed to either severe stenosis in large arteries or acute hypotensive events, whereas external WI are thought to be caused by embolism. The aim of this study was to determine the etiologic background and prognosis of external and internal WI in our patients.

METHODS

We reviewed the medical records and diffusion-weighted images of the patients who were admitted to our stroke unit with acute ischemic stroke between January 2012 and November 2014. The demographics, clinical features, radiologic investigations, and other etiologic tests of the patients with internal or external WI were recorded. We determined etiologic stroke subtypes according to the automated Causative Classification System.

RESULTS

Fifty-three patients with WI were detected in our registry. Twenty-two (41.5%) of them were women. The mean age was 69 ± 12.8 (33-98) years. Twenty-one (39.6%) patients had external WI: 7 (33.3%) of them had large-artery atherosclerosis (LAA), 8 (38.1%) patients had cardioembolism, 3 (14.3%) patients had stroke due to other causes (vasculitis; n = 3), and etiologic subtype was undetermined in 3 patients (14.3%). Thirty-two (60.4%) patients had internal WI: 21 (65.6.%) of them had LAA, 5 (15.6%) patients had cardioembolism, 3 (9.4%) patients had stroke due to other causes (aneurysm; n = 1, hypercoagulability due to chronic myeloid leukemia; n = 1, vasculitis; n = 1), and etiologic subtype of 3 (9.4%) patients remained cryptogenic. LAA was significantly associated with internal WI (P = .024). Hypertension was more common in patients with internal WI (P = .035).

CONCLUSIONS

In this series, cardioembolism was the most common etiologic subtype in the patients with external WI, whereas internal WI were significantly associated with LAA. Uncommon causes should also be investigated in cryptogenic 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.

Longitudinal brain white matter alterations in minimal hepatic encephalopathy before and after liver transplantation

Cerebral edema is the common pathogenic mechanism for cognitive impairment in minimal hepatic encephalopathy. Whether complete reversibility of brain edema, cognitive deficits, and their associated imaging can be achieved after liver transplantation remains an open question. To characterize white matter integrity before and after liver transplantation in patients with minimal hepatic encephalopathy, multiple diffusivity indices acquired via diffusion tensor imaging was applied. Twenty-eight patients and thirty age- and sex-matched healthy volunteers were included. Multiple diffusivity indices were obtained from diffusion tensor images, including mean diffusivity, fractional anisotropy, axial diffusivity and radial diffusivity. The assessment was repeated 6–12 month after transplantation. Differences in white matter integrity between groups, as well as longitudinal changes, were evaluated using tract-based spatial statistical analysis. Correlation analyses were performed to identify first scan before transplantation and interval changes among the neuropsychiatric tests, clinical laboratory tests, and diffusion tensor imaging indices. After transplantation, decreased water diffusivity without fractional anisotropy change indicating reversible cerebral edema was found in the left anterior cingulate, claustrum, postcentral gyrus, and right corpus callosum. However, a progressive decrease in fractional anisotropy and an increase in radial diffusivity suggesting demyelination were noted in temporal lobe. Improved pre-transplantation albumin levels and interval changes were associated with better recoveries of diffusion tensor imaging indices. Improvements in interval diffusion tensor imaging indices in the right postcentral gyrus were correlated with visuospatial function score correction. In conclusion, longitudinal voxel-wise analysis of multiple diffusion tensor imaging indices demonstrated different white matter changes in minimal hepatic encephalopathy patients. Transplantation improved extracellular cerebral edema and the results of associated cognition tests. However, white matter demyelination may advance in temporal lobe.

Posterior reversible encephalopathy syndrome in pediatric acute leukemia: Case series and literature review

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state coupled with a unique radio imaging appearance. We describe this rare, mostly reversible condition in five cases undergoing similar treatment under preset protocol (MCP-841) for acute lymphoblastic leukemia (ALL) at our centre. Hypertension is a well-known adverse effect of high-dose corticosteroid therapy primarily mediated by its effects on the mineralocorticoid receptor especially in pediatric population and we hypothesize that this may be the etiology of PRES in two of these patients.

Sickle cell disease and posterior reversible leukoencephalopathy

Sickle cell disease can present with neurological manifestations. One such presentation is with posterior reversible leukoencephalopathy also known as reversible posterior leukoencephalopathy. The condition is classically described as reversible over time; it commonly presents with oedematous changes involving the white matter of the occipital and parietal regions. Only a few patients with the association between sickle cell disease and posterior reversible leukoencephalopathy have been described in the adult literature. We present two patients from our institutions to emphasise the association between the two conditions and summarise the published cases in the literature.

Neurotoxicity of commonly used hepatic drugs

Neurologic complications are common side-effects of immunosuppressive medications used in the prevention of graft rejection after organ transplantation. The medications most commonly encountered include the calcineurin inhibitors and mycophenolate mofetil. Depression is the most commonly encountered neurotoxicity; however, severe but rare adverse neurological effects related to these therapies have been reported. Interferons, ribavirin, and protease inhibitors are therapeutic options commonly encountered in the treatment of hepatitis. Nucleoside analogs such as adefovir dipivoxil and entecavir carry significant risks for the development of lactic acidosis and hepatic dysfunction; however, most common adverse effects to these therapies in general are mild. While the mechanisms of action are poorly elucidated, they are discussed along with treatment strategies.

Calcineurin-inhibitor pain syndrome

BACKGROUND

There has been increased recognition of calcineurin, a phosphoprotein serine/threonine phosphatase enzyme, in the regulation of many physiologic systems. Calcineurin mediates activation of lymphocytes, which play a role in immune response. Widely distributed in the central nervous system, calcinuerin also plays an important role in sensory neural function, via its role in the regulation of newly discovered 2-pore potassium channels, which greatly influence neuronal resting membrane potentials. Calcinuerin inhibition is the mechanism of action of immunomodulatory drugs such as cyclosporine and tacrolimus, which are widely used in transplantation medicine to prevent rejection. While important for immunosuppression, the use of calcineurin inhibitors has been associated with the development of a new pain syndrome called the calcineurin pain syndrome, which appears to be an untoward complication of the interruption of the physiologic function of calcineurin.

METHODS

This is a narrative review focusing on the epidemiology, pathophysiology, characterization of a newly recognized pain syndrome associated with the use of calcineurin inhibitors.

RESULTS

The use of immunosuppressants however is associated with several well-known toxicities to which the calcineurin pain syndrome can be added. The development of this syndrome most likely involves altered nociceptive processing due to the effect of calcineurin inhibition on neuronal firing, as well as effects of calcineurin on vascular tone. The most striking aspect of the treatment of this syndrome is the response to calcium channel blockers, which suggest that the effects of calcineurin inhibition on vascular tone play an important role in the development of the calcineurin pain syndrome.

CONCLUSION

The calcineurin syndrome is a newly recognized complication associated with the use of calcineurin inhibitors. There is no standard therapy at this time but anecdotal reports suggest the effectiveness of calcium channel blockers.

Relationships between edema degree and clinical and biochemical parameters in posterior reversible encephalopathy syndrome: a preliminary study

The objective of the study was to investigate the associations between the degree of edema with the clinical and biochemical parameters such as serum lactate dehydrogenase (LDH), albumin (ALB) in posterior reversible encephalopathy syndrome (PRES) patients. Forty-nine patients with typical clinical symptoms and characteristic MR imaging findings of PRES were included in this study. Lactate dehydrogenase and ALB were analyzed with the immunoluminometric assays. Fluid-attenuated inversion recovery images were used to evaluate the distribution of the extent or severity of vasogenic edema by two observers. Correlation analysis between the scores of brain edema and the blood pressures, clinical conditions and biochemical parameters was performed. No significant difference of brain edema score was found between patients with eclampsia, chronic renal failure and other clinical condition (P > 0.05). Both mean arterial pressures and LDH level were moderately correlated with the scores of brain edema distribution (Spearman's ρ test, r = 0.405 and 0.497, respectively, P < 0.01). Serum ALB level was not correlated with the scores of brain edema distribution (P > 0.05). Larger and more diffuse lesions may be predicted by higher LDH level and blood pressure. The overall severity of the systemic process might be predicted by the degree of edema expression in PRES.

[Posterior reversible encephalopathy syndrome]

Posterior reversible encephalopathy syndrome (PRES) is a clinically and radiologically defined syndrome characterized by seizures, headaches, visual disturbances, and altered mental status or focal neurological deficits. Imaging frequently shows abnormalities in the posterior brain regions, especially the occipital and the parietal lobes. PRES has been described in association with a wide spectrum of underlying causes. The most common conditions include hypertension, renal disease, preeclampsia/eclampsia, or status post transplantation. The pathophysiology of PRES has not been sufficiently elucidated as yet; however, endothelial damage caused by different mechanisms possibly plays a central role. The prognosis of PRES is usually benign when intensive care and withdrawal of the causative agent is instituted early. Delay in diagnosis and treatment may lead to complications and permanent neurological deficits. The clinical and radiological landmarks of this syndrome as well as causes, pathophysiological hypotheses, and the basic therapeutic principles of PRES are the subject of the present review.

Border zone infarcts: pathophysiologic and imaging characteristics

Border zone or watershed infarcts are ischemic lesions that occur in characteristic locations at the junction between two main arterial territories. These lesions constitute approximately 10% of all brain infarcts and are well described in the literature. Their pathophysiology has not yet been fully elucidated, but a commonly accepted hypothesis holds that decreased perfusion in the distal regions of the vascular territories leaves them vulnerable to infarction. Two types of border zone infarcts are recognized: external (cortical) and internal (subcortical). To select the most appropriate methods for managing these infarcts, it is important to understand the underlying causal mechanisms. Internal border zone infarcts are caused mainly by hemodynamic compromise, whereas external border zone infarcts are believed to result from embolism but not always with associated hypoperfusion. Various imaging modalities have been used to determine the presence and extent of hemodynamic compromise or misery perfusion in association with border zone infarcts, and some findings (eg, multiple small internal infarcts) have proved to be independent predictors of subsequent ischemic stroke. A combination of several advanced techniques (eg, diffusion and perfusion magnetic resonance imaging and computed tomography, positron emission tomography, transcranial Doppler ultrasonography) can be useful for identifying the pathophysiologic process, making an early clinical diagnosis, guiding management, and predicting the outcome.

Toxic agents causing cerebellar ataxias

The cerebellum is particularly vulnerable to intoxication and poisoning, especially so the cerebellar cortex and Purkinje neurons. In humans, the most common cause of a toxic lesion to the cerebellar circuitry is alcohol related, but the cerebellum is also a main target of drug exposure (such as anticonvulsants, antineoplastics, lithium salts, calcineurin inhibitors), drug abuse and addiction (such as cocaine, heroin, phencyclidine), and environmental toxins (such as mercury, lead, manganese, toluene/benzene derivatives). Although data for the prevalence and incidence of cerebellar lesions related to intoxication and poisoning are still unknown in many cases, clinicians should keep in mind the list of agents that may cause cerebellar deficits, since toxin-induced cerebellar ataxias are not rare in daily practice. Moreover, the patient's status may require immediate therapies when the intoxication is life-threatening.

Posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is characterized by headache, altered mental status, visual disturbances, and seizures. Radiological features typically include edema of the posterior cerebral regions, especially of the parietooccipital lobes. Atypical imaging features, such as involvement of anterior cerebral regions, deep white matter, and the brain stem are also frequently seen. Vasoconstriction is common in vascular imaging. Different conditions have been associated with PRES, but toxemia of pregnancy, solid organ or bone marrow transplantation, immunosuppressive treatment, cancer chemotherapy, autoimmune diseases, and hypertension are most commonly described. The pathophysiology of PRES is unclear and different hypotheses are being discussed. Posterior reversible encephalopathy syndrome is best managed by monitoring and treatment in the setting of a neurointensive care unit. The prognosis is usually benign with complete reversal of clinical symptoms within several days, when adequate treatment is immediately initiated. Treatment of severe hypertension, seizures, and withdrawal of causative agents represent the hallmarks of specific therapy in PRES. Delay in diagnosis and treatment may lead to permanent neurological sequelae. Therefore, awareness of PRES is of crucial importance for the intensivist.

Vasospasm is a significant factor in cyclosporine-induced neurotoxicity: case report

BACKGROUND

The aetiology of central nervous system lesions observed in cerebral cyclosporine neurotoxicity remains controversial.

CASE PRESENTATION

We report a 48-year-old woman with a non-severe aplastic anaemia who presented with stroke-like episodes while on cyclosporine treatment.Transcranial Doppler ultrasound revealed severely elevated flow velocities in several cerebral vessels, consistent with vasospasm. Immediately after reducing the cyclosporine dose, the stroke-like episodes disappeared. Only after cyclosporine withdrawal the transcranial Doppler ultrasound abnormalities fully resolved.

CONCLUSIONS

This case demonstrates a significant role of vasospasm in the pathway of cyclosporine-induced neurotoxicity. Transcranial Doppler ultrasound is an effective tool for the diagnosis and follow-up of cyclosporine-induced vasospasm.

Neurocognitive-neurological complications of liver transplantation: a review

Neurological complications are common after liver transplantation (LT) and they are associated with a significant morbidity. Long-term effects of LT on cognitive and psychological outcomes are not clear. The objective of this study was to summarize the present knowledge on the neurological and cognitive complications of LT, resulting from a systematic review of the literature in the last 10 years. Several studies have investigated the incidence and the pathophysiology of neurological complications; in contrast, the knowledge of cognitive and psychological status after LT is poor. Currently, the effect of LT on mental performance is debated. Some studies have shown an improvement of cognitive function after OLTX and, at the same time, a persistence of different cognitive deficits. In addition, the quality of life (QoL) and the psychological status after LT seem to improve but LT recipients have significant deficiencies in most QoL domains. Consequently, future studies are necessary in order to investigate cognitive alterations and QoL in LT recipients.

Hemorrhage in posterior reversible encephalopathy syndrome: imaging and clinical features

BACKGROUND AND PURPOSE

Hemorrhage is known to occur in posterior reversible encephalopathy syndrome (PRES), but the characteristics have not been analyzed in detail. The purpose of this study was to evaluate the imaging and clinical features of hemorrhage in PRES.

MATERIALS AND METHODS

Retrospective assessment of 151 patients with PRES was performed, and 23 patients were identified who had intracranial hemorrhage at toxicity. Hemorrhage types were identified and tabulated, including minute focal hemorrhages (<5 mm), sulcal subarachnoid hemorrhage, and focal hematoma. Clinical features of hemorrhage and nonhemorrhage PRES groups were evaluated, including toxicity blood pressure, coagulation profile/platelet counts, coagulation-altering medication, and clinical conditions associated with PRES. Toxicity mean arterial pressure (MAP) groups were defined as normal (<106 mm Hg), mildly hypertensive (106-116 mm Hg), or severely hypertensive (>116 mm Hg).

RESULTS

The overall incidence of hemorrhage was 15.2%, with borderline statistical significance noted between the observed clinical associations (P = .07). Hemorrhage was significantly more common (P = .02) after allogeneic bone marrow transplantation (allo-BMT) than after solid-organ transplantation. The 3 hemorrhage types were noted with equal frequency. A single hemorrhage type was found in 16 patients, with multiple types noted in 7. Patients undergoing therapeutic anticoagulation were statistically more likely to develop hemorrhage (P = .04). No difference in hemorrhage incidence was found among the 3 blood pressure subgroups (range, 14.9%-15.9%).

CONCLUSIONS

Three distinct types of hemorrhage (minute hemorrhage, sulcal subarachnoid hemorrhage, hematoma) were identified in PRES with equal frequency. The greatest hemorrhage frequency was seen after allo-BMT and in patients undergoing therapeutic anticoagulation. Hemorrhage rate was independent of the toxicity blood pressure.

Posterior reversible encephalopathy syndrome, part 1: fundamental imaging and clinical features

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state coupled with a unique CT or MR imaging appearance. Recognized in the setting of a number of complex conditions (preeclampsia/eclampsia, allogeneic bone marrow transplantation, organ transplantation, autoimmune disease and high dose chemotherapy) the imaging, clinical and laboratory features of this toxic state are becoming better elucidated. This review summarizes the basic and advanced imaging features of PRES, along with pertinent features of the clinical and laboratory presentation and available histopathology. Many common imaging/clinical/laboratory observations are present among these patients, despite the perception of widely different associated clinical conditions.

Posterior reversible encephalopathy syndrome, part 2: controversies surrounding pathophysiology of vasogenic edema

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state accompanied by a unique brain imaging pattern typically associated with a number of complex clinical conditions including: preeclampsia/eclampsia, allogeneic bone marrow transplantation, solid organ transplantation, autoimmune diseases and high dose cancer chemotherapy. The mechanism behind the developing vasogenic edema and CT or MR imaging appearance of PRES is not known. Two theories have historically been proposed: 1) Severe hypertension leads to failed auto-regulation, subsequent hyperperfusion, with endothelial injury/vasogenic edema and; 2) vasoconstriction and hypoperfusion leads to brain ischemia and subsequent vasogenic edema. The strengths/weaknesses of these hypotheses are reviewed in a translational fashion including supporting evidence and current available imaging/clinical data related to the conditions that develop PRES. While the hypertension/hyperperfusion theory has been most popular, the conditions associated with PRES have a similar immune challenge present and develop a similar state of T-cell/endothelial cell activation that may be the basis of leukocyte trafficking and systemic/cerebral vasoconstriction. These systemic features along with current vascular and perfusion imaging features in PRES appear to render strong support for the older theory of vasoconstriction coupled with hypoperfusion as the mechanism.

Posterior reversible encephalopathy syndrome after solid organ transplantation

BACKGROUND AND PURPOSE

Posterior reversible encephalopathy syndrome (PRES) is known to occur after solid organ transplantation (SOT), potentially associated with cyclosporine and tacrolimus. In this study, we assess the frequency and clinical and imaging characteristics of PRES after SOT.

MATERIALS AND METHODS

We identified 27 patients (13 men and 14 women; age range, 22-72 years) who developed PRES after SOT. Features noted included SOT subtype, incidence and timing of PRES, infection and rejection, mean arterial pressure (MAP), and toxicity brain edema.

RESULTS

PRES developed in 21 (0.49%) of 4222 patients who underwent transplantation within the study period (no significant difference among SOT subtypes). Transplantation was performed in 5 patients before the study period, and 1 patient underwent transplantation elsewhere. In consideration of all 27 patients, PRES typically developed in the first 2 months in patients who had SOT of the liver (9 of 10 patients) and was associated with cytomegalovirus (CMV), mild rejection, or systemic bacterial infection. PRES also typically developed after 1 year in patients who had SOT of the kidney (8 of 9 patients) and was associated with moderate rejection or bacterial infection. Toxicity MAP was significantly lower (P < .001) in liver transplants (average MAP, 104.8 +/- 16 mm Hg) compared with that in kidney transplants (average MAP, 143 +/- 20 mm Hg). Toxicity brain edema was significantly greater (P < .001) in patients who had liver transplants and developed PRES compared with patients who had undergone kidney transplants despite severe hypertension in those who had the kidney transplants.

CONCLUSION

Patients who had undergone SOTs have a similar low incidence of developing PRES. Differences between those who have had liver and kidney transplants included time after transplant, toxicity MAP, and PRES vasogenic edema noted at presentation. In patients who have undergone kidney transplants, severely elevated MAP was associated with reduced, not greater, brain edema.

Catheter angiography, MR angiography, and MR perfusion in posterior reversible encephalopathy syndrome

BACKGROUND AND PURPOSE

The cause of posterior reversible encephalopathy syndrome (PRES) is unknown. Two primary hypotheses exist: 1) hypertension exceeding auto-regulatory limits leading to forced hyper-perfusion and 2) vasoconstriction and hypo-perfusion leading to ischemia with resultant edema. The purpose of this study was to evaluate the catheter angiography (CA), MR angiography (MRA), and MR perfusion (MRP) features in PRES in order to render further insight into its mechanism of origin.

MATERIALS AND METHODS

In 47 patients with PRES, 9 CAs and 43 MRAs were evaluated for evidence of vasculopathy (vasoconstriction and vasodilation), and 15 MRP studies were evaluated for altered relative cerebral blood volume (rCBV) in PRES lesions and regions. Visualization of vessels on MRA and toxicity blood pressures were compared with the extent of hemispheric vasogenic edema.

RESULTS

Vasculopathy was present in 8 of 9 patients on CA (direct correlation to MRA in 3/6 patients). At MRA, moderate to severe vessel irregularity consistent with vasoconstriction and vasodilation was present in 30 of 43 patients and vessel pruning or irregularity in 7 patients, with follow-up MRA demonstrating reversal of vasoconstriction or vasodilation in 9 of 11 patients. Vasogenic edema was less in patients with hypertension compared with patients who were normotensive. Preserved normal length of the posterior cerebral artery (PCA) was commonly seen in patients with severe hypertension despite diffuse or focal vasoconstriction or vasodilation. In these patients, lengthier visualization of the distal PCA correlated with a lower grade of hemispheric edema (P = .002). Cortical rCBV was significantly reduced in 51 of 59 PRES lesions and regions compared with a healthy reference cortex (average 61% of reference cortex) with mild decrease in the remainder.

CONCLUSION

Vasculopathy was a common finding on CA and MRA in our patients with PRES, and MRP demonstrated reduced cortical rCBV in PRES lesions. Vasogenic edema was reduced in patients with hypertension, and superior distal PCA visualization correlated with reduced hemispheric edema in patients with PRES and severe hypertension.

Distinct imaging patterns and lesion distribution in posterior reversible encephalopathy syndrome

BACKGROUND AND PURPOSE

Although the term posterior reversible encephalopathy syndrome (PRES) was popularized because of the typical presence of vasogenic edema in the parietal and occipital lobes, other regions of the brain are also frequently affected. We evaluated lesion distribution with CT and MR in a large cohort of patients who experienced PRES to comprehensively assess the imaging patterns identified.

MATERIALS AND METHODS

The locations of the PRES lesion at toxicity were comprehensively identified and tabulated in 136 patients by CT (22 patients) and MR (114 patients) imaging including the hemispheric, basal ganglial, and infratentorial locations. Clinical associations along with presentation at toxicity including blood pressure were assessed.

RESULTS

Vasogenic edema was consistently present in the parietal or occipital regions (98%), but other locations were common including the frontal lobes (68%), inferior temporal lobes (40%), and cerebellar hemispheres (30%). Involvement of the basal ganglia (14%), brain stem (13%), and deep white matter (18%) including the splenium (10%) was not rare. Three major patterns of PRES were noted: the holohemispheric watershed (23%), superior frontal sulcal (27%), and dominant parietal-occipital (22%), with additional common partial or asymmetric expression of these primary PRES patterns (28%).

CONCLUSION

Involvement of the frontal lobe, temporal lobe, and cerebellar hemispheres is common in PRES, along with the occasional presence of lesions in the brain stem, basal ganglia, deep white matter, and splenium. Three primary PRES patterns are noted in the cerebral hemispheres, along with frequent partial or asymmetric expression of these PRES patterns. Awareness of these patterns and variations is important to recognize PRES neurotoxicity more accurately when present.

Cerebellar atrophy in Schimke-immuno-osseous dysplasia

Schimke-immuno-osseous dysplasia is an autosomal-recessive multisystem disorder with the prominent clinical features disproportionate growth failure, progressive renal failure, and T-cell immunodeficiency. Neurological symptoms caused by transient ischemic attacks (TIAs) and strokes are a typical clinical finding in severe SIOD. Cerebral ischemia and white matter changes, moyamoya phenomena and absence of a cerebellar hemisphere and partial absence of the cerebellar vermis have been described in patients with severe SIOD. We present three SIOD patients with atrophy of the caudal parts of the cerebellar vermis (posterior lobule) and of the cerebellar hemispheres. We hypothesize that these cerebellar abnormalities are a continuum of the ongoing vascular disease in severe SIOD.

"Recurrent" posterior reversible encephalopathy syndrome: report of 3 cases--PRES can strike twice!

In a retrospective review, 3 (3.8%) of 78 patients developed recurrent posterior reversible encephalopathy syndrome. Underlying clinical conditions included sickle cell disease, antibody-positive autoimmune disease, and allogeneic bone marrow transplantation. Infection (bacterial/viral) was suspected or documented in both episodes in all 3 patients. Evidence of endothelial injury (schistocyte formation and increased lactate dehydrogenase) was documented in all patients, and multiple organ dysfunction syndrome developed during the hospital course of all admissions.

Cyclosporine-Associated Leukoencephalopathy in Organ Transplant Recipients: Experience of Three Clinical Cases

Leukoencephalopathy is a structural alteration of cerebral white matter mainly involving damage to myelin. Several reports have linked cyclosporine (CsA) with this alteration. The clinical features vary from qualitative alterations of consciousness to neurological deficits. Magnetic resonance imaging (MRI) of the brain demonstrates the damage to the white matter, which is essential for the differential diagnosis. We describe three clinical cases of leukoencephalopathy. The first case is a 43-year-old man received a cadaveric kidney transplant using immunosuppression with of mycophenolate mofetil, prednisone, and CsA. Four months later he developed meningism and bilateral sixth nerve palsy. The second case is a 50-year-old man with a cadaveric kidney transplant received immunosuppressive treatment with azathioprine and prednisone. As a result of gouty arthritis of the ankle, azathioprine was replaced with CsA to allow addition of allopurinol. Two weeks later he developed confusion and personality changes. The third case is a 16-year-old man received a orthotopic liver transplant. Postoperatively he suffered generalized tonic-clonic seizures. In all patients the CsA levels were toxic and signs of neurological alterations were present on MRI. All patients recovered rapidly after CsA withdrawal.

Variable incidence of cyclosporine and FK-506 neurotoxicity in hematopoeitic malignancies and marrow conditions after allogeneic bone marrow transplantation

INTRODUCTION

This study examines whether malignant disease under treatment influences the incidence of cyclosporine or FK-506 neurotoxicity after myeloablative conditioning and allogeneic bone marrow transplantation (allo-BMT).

METHODS

Review of 290 patients who received myeloablative conditioning prior to allo-BMT and cyclosporine/FK-506 identified 21 (7.2%) patients with neurotoxicity confirmed by computed tomography or magnetic resonance. Underlying malignancy necessitating allo-BMT included leukemias (67%), lymphoma (10%), myelodysplastic syndrome (10%), and multiple myeloma (MM). Frequency of neurotoxicity by disease was compared.

RESULTS

The highest incidence of neurotoxicity was present with MM (25%), whereas the lowest incidence was present with lymphoma (2.7%). Other diseases demonstrated intermediate incidence, including acute leukemias (10%), myelodysplastic syndrome (6.4%), and chronic myelogenous leukemia (4.9%).

CONCLUSION

Cyclosporine/FK-506 neurotoxicity varied according to the underlying malignancy. The variable susceptibility to the development of neurotoxicity in this population may depend on the interaction of host vasculature with disease specific factors. Understanding the cause of neurotoxicity could improve survival after allo-BMT.

Characteristics and correlates of cognitive functioning following bone marrow transplantation

Patients who undergo bone marrow transplantation (BMT) often report cognitive problems following treatment. This study used cognitive tests and a self-report measure of subjective cognitive complaints to determine (1) the rate of objective cognitive impairment in a sample of 65 BMT patients, and (2) the correspondence of patients' cognitive complaints to their actual cognitive performance. At 6 months following BMT, patients were assessed in seven cognitive domains--attention, verbal learning, verbal memory, visual memory, simple executive function, complex executive function, and psychomotor speed. Cognitive complaints were likewise assessed. In all, 51% had at least mild impairment (-1 standard deviation (s.d.) below published norms) in one or more cognitive domains, with 28% demonstrating moderate-to-severe impairment (-2 s.d.). Older patients and patients with lower IQ were more likely to score in the impaired range on objective cognitive tests, with males and the less educated showing trends toward scores in the impaired range. Younger patients made significantly more cognitive complaints. Total cognitive complaints were unrelated to average cognitive performance, and complaints in specific cognitive domains were largely unrelated to objective performance on corresponding domains. Findings suggest that patients who complain about their cognitive performance following BMT differ from those who experience actual deficits.

Non-infectious manifestations of stem cell transplantation

Stem cell transplantation (SCT) is now commonplace within medical practice. With growth in transplant activities, outcomes are likely to continue to improve. Increasing numbers of the population now face life after transplantation. The aetiology of post transplant complications is multifactorial. Background knowledge of SCT and common, radiographically detectable, non-infective complications are important in everyday clinical practice. A review of these complications using a variety of imaging modalities is presented and the process of SCT briefly described. Tumour recurrence is outside the remit of this review.

High-fat diets impede the lowering effect of cyclosporine a on rat brain lipids and interact with the expression of apolipoproteins E and J

Cyclosporine A (CsA), a common immunosuppressive agent, produces hyperlipidemia and apolipoprotein profile alterations in plasma as well as neurological and psychiatric complications. In rats, 10 mg CsA/kg/d treatments for 3 wk induce alterations of the electroencephalogram, and of the blood and brain lipids. Using this model, we evaluated whether triacylglycerol (TG)- and lecithin (PC)-enriched diets, reported to decrease epileptic episodes (TG) and to improve memory, could modify the effects of CsA treatment on brain lipids and possibly change apolipoprotein (apo) E and apoJ gene expression. To evaluate this hypothesis, three groups of rats were treated for 3 wk with CsA and received a low-fat, PC, or TG diet. Three other groups were fed the above-mentioned diets and were treated with the CsA solvent. As a control, one group was fed only the low-fat diet. The CsA-mediated decreases in brain cholesterol and PC contents, under a low-fat diet, were eliminated by the TG and PC diets. These high-fat diets induced a global increase in hippocampal transcriptional activity, as revealed by elevated polyadenylated RNA levels. The apoE and apoJ mRNA levels in the cortex and hippocampus of rats receiving the solvent were not statistically different between the TG- and PC-enriched diets but showed important variations compared with the low-fat diet solvent-treated group. A differential effect between the two high-fat diets was observed in the hippocampus, resulting in a significant increase of the apoE to apoJ ratio with the PC diet. The balance between apoE and apoJ is presumed to be important in encephalopathic mechanisms, by its involvement through low levels of brain cholesterol and PC, that might be associated with mental disorders. Our results therefore suggest that diet enrichment with polyunsaturated fat might be beneficial during CsA therapy. However, if the high levels in PC used here are more beneficial on CsA peripheral side effects than similar enrichment in TG, this does not seem to be the case in the brain. Thus, lower levels in PC should be tested.

Neuropsychologic changes from before transplantation to 1 year in patients receiving myeloablative allogeneic hematopoietic cell transplant

Research indicates that myeloablative hematopoietic cell transplantation (HCT) impairs neurocognitive function. However, prospective studies on long-term effects are lacking. This longitudinal study examined neurocognitive changes over the first year in 142 adult recipients of allogeneic HC transplants who received neuropsychologic testing before transplantation and again after 80 days and 1 year. Age-, sex-, and education-adjusted population-based standardized scores were used for normative comparisons. Performance on all tests declined from before transplantation to 80 days (P &lt; .05) and improved by 1 year (P &lt; .05), returning to pretransplantation levels on all tests except for grip strength and motor dexterity. Although verbal fluency and memory recovered by 1 year, both were below norms at all 3 testing times (P &lt; .01). Logistic regressions indicated that patients without chemotherapy, other than hydroxyurea, previous to HCT and patients not receiving chronic graft-versus-host disease (GVHD) medication at 1 year had lower risk of impaired function (P &lt; .05). In conclusion, HCT was associated with significant generalized decline in neurocognitive performance at 80 days, with subsequent recovery to pretransplantation levels by 1 year for most survivors, except on motor tasks. Results indicate that long-term cognitive decrements, as distinct from motor disabilities, infrequently derive directly from HCT. (Blood. 2004;104:3386-3392)

Diffusion-weighted MRI and ADC mapping in FK506 neurotoxicity

FK506 is a newly developed potent immunosuppressant for preventing rejection after organ transplantation. However, FK506 can induce central nervous system toxicity. Until now the pathogenic mechanism of FK506 neurotoxicity was unclear. We report the findings of diffusion-weighted MRI and apparent diffusion coefficient (ADC) mapping of a FK506 neurotoxicity patient who showed increased signal intensities in both parieto-occipital lobes on T(2) weighted images, diffusion-weighted images and ADC maps. These findings suggest that a vasogenic oedema rather than a cytotoxic oedema may play a pivotal role in FK506 neurotoxicity pathogenesis.

Long-term outcomes of allogeneic stem cell transplant recipients after calcineurin inhibitor-induced neurotoxicity

Calcineurin inhibitor-induced central nervous system toxicities are uncommon and often resolve after discontinuation of the offending drug. The long-term outcome of these patients is, however, unknown. Resolution of symptoms occurred in 70% of 30 allografted recipients who developed calcineurin inhibitor-induced neurotoxicity. When patients were rechallenged with the same or a different calcineurin inhibitor, symptoms recurred in 41%, leading to permanent discontinuation of the drug. De novo or progressive acute graft-versus-host disease (GVHD) was observed in 54% of patients at a median of 7 d (range 1-70 d) after initial onset of neurotoxicity. The prognosis was grim, with 24 (80%) of these patients dying a median 33 d after the onset of neurotoxicity (range 2-594 d). GVHD and/or infection occurred in 54% and were the most common primary causes of death. We conclude that calcineurin inhibitor-induced neurotoxicity is frequently reversible but associated with a poor prognosis.

Effects of cyclosporine-A on brain lipids and apolipoprotein E, J gene expression in rats

Cyclosporine-A, an immunosuppressive agent, is known to produce complications such as seizures and encephalopathies. It alters peripheral lipid metabolism, but its effect on brain lipid metabolism is unknown. Alterations in brain cholesterol and phosphatidylcholine levels, as well as in apolipoproteine E and J gene expression, are reportedly involved in epilepsy and Alzheimer's disease (AD) and were here evaluated in rats following administration of cyclosporine-A for 3 weeks. Unesterified cholesterol and phospholipid brain levels were decreased by cyclosporine whereas apolipoprotein E and J mRNA levels were not altered in hippocampus or in cortex. These alterations in brain lipid metabolism are not similar to that reported in epilepsy or AD and exclude the involvement of apolipoprotein E and J over-expression in cyclosporine-mediated neurological disorders.

Blindness after liver transplant

A 58-year-old woman developed a generalized seizure 12 days after undergoing liver transplantation and awakened with persistent hand motions vision binocularly. Cyclosporine levels were normal and blood pressure was only mildly elevated. The ophthalmic and neurologic examinations were otherwise normal. Brain MRI revealed bilateral parieto-occipital white matter signal abnormalities consistent with vasogenic edema. The cyclosporine was abruptly replaced with tacrolimus and the patient recovered normal vision within 48 hours. A subsequent brain MRI taken 30 days later showed that the patient had reverted to normal. This is an example of posterior leukoencephalopathy owing to cyclosporine toxicity. It points out that visual loss may be an isolated or most prominent clinical manifestation, cyclosporine and blood pressure levels may be normal, deficits are reversible if cyclosporine is promptly discontinued, and tacrolimus, a similar immunosuppressive agent, may be a safe substitute.

Clinical findings and magnetic resonance imaging in severe cyclosporine-related neurotoxicity after allogeneic bone marrow transplantation

OBJECTIVES

Severe neurotoxicity is a recognized complication of cyclosporin A (cyclosporine, CSA). Neuroimaging studies typically show reversible brain lesions, predominantly confined to the white matter. Our aim was to delineate clinical characteristics and to specify results of magnetic resonance imaging (MRI) and computerised tomography (CT) scan findings.

METHODS

Cases of severe cyclosporine-related neurotoxicity (SNCT) were identified among a series of 129 consecutive allogeneic transplant recipients. Clinical features were analysed, including CSA levels, electrolytes, cholesterolemia and magnesemia. MRI and/or CT scans were obtained within 24 h to 4 d after the onset of neurotoxicity.

RESULTS

Six patients (4.6%) developed a prodromal phase (headache and/or hypertension), followed by SCNT, including generalized seizures (n = 5), occipital blindness (n = 1) and hemiparesis (n = 1). There was no correlation between the laboratory findings and the onset of SNCT. All patients were on corticosteroid treatment. MRI studies showed hyperintensity lesions, predominantly in the posterior cerebrum, with both subcortical and cortical involvement in 4 out of 5 patients. Cerebellar involvement (n = 4) was also a frequent finding. The signal abnormalities, corresponding to the anastomotic border zones between major cerebral and cerebellar arteries, were limited to the respective cortical areas.

CONCLUSION

Association of corticosteroids is a trigger in the development of SCNT. MRI is recommended for the early identification of the transient brain lesions in patients with a prodromal phase. The more specific distribution of the lesions in the anastomotic border zones suggests vascular injury as a contributing factor in the pathology of SNCT.

Cyclosporin A-related cerebral vasculopathy

The use of cyclosporin A has been associated with several side-effects, including neurotoxicity. The mechanism of toxicity is not well known. We report two patients treated with cyclosporin A who developed lesions in the cerebral white matter associated with abnormally elevated cerebral blood flow velocities on transcranial doppler ultrasound and abnormal vascular appearance on magnetic resonance angiography. Bone Marrow Transplantation (2000) 26, 801-804.