Reversible posterior leukoencephalopathy following organ transplantation. Description of two cases

Posterior reversible encephalopathy syndrome in stroke-prone spontaneously hypertensive rats on high-salt diet

Stroke-prone spontaneously hypertensive rats (SHRSP) on high-salt diet are characterized by extremely high arterial pressures, and have been endorsed as a model for hypertensive small vessel disease and vascular cognitive impairment. However, rapidly developing malignant hypertension is a well-known cause of posterior reversible encephalopathy syndrome (PRES) in humans, associated with acute neurological deficits, seizures, vasogenic cerebral edema and microhemorrhages. In this study, we aimed to examine the overlap between human PRES and SHRSP on high-salt diet. In SHRSP, arterial blood pressure progressively increased after the onset of high-salt diet and seizure-like signs emerged within three to five weeks. MRI revealed progressive T2-hyperintense lesions suggestive of vasogenic edema predominantly in the cortical watershed and white matter regions. Histopathology confirmed severe blood-brain barrier disruption, white matter vacuolization and microbleeds that were more severe posteriorly. Hematological data suggested a thrombotic microangiopathy as a potential underlying mechanism. Unilateral common carotid artery occlusion protected the ipsilateral hemisphere from neuropathological abnormalities. Notably, all MRI and histopathological abnormalities were acutely reversible upon switching to regular diet and starting antihypertensive treatment. Altogether our data suggest that SHRSP on high-salt diet recapitulates the neurological, histopathological and imaging features of human PRES rather than chronic progressive small vessel disease.

PRES: Review of Histological Features

Posterior reversible encephalopathy syndrome was described in 1996 as a clinical-neuroimaging entity characterized by parieto-occipital watershed-region edema without overt infarction. It has been linked to hypertension, eclampsia, immunosuppressive therapies, infections, and autoimmune disorders. The condition usually has an acute onset, presents with seizures, and ameliorates within days. There have been few neuropathological studies, but in some cases, tissue damage may be more permanent.

Reversible Posterior Leukoencephalopathy Syndrome following Sunitinib Therapy: A Case Report and Review of the Literature

Sunitinib is one of the standard targeted therapies used in metastatic renal cell carcinoma. It is generally a reasonably tolerated oral systemic therapy but can be occasionally associated with life-threatening toxicities. We present a case of reversible posterior encephalopathy, which is a rare but recognised side effect of the treatment.

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.

Clinical outcomes and risk factors for posterior reversible encephalopathy syndrome in systemic lupus erythematosus: a multicentric case-control study

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a well-known but rare complication in patients (<1%) with systemic lupus erythematosus (SLE). However, current epidemiological data are quite scant. The aim of the present study was to describe potentially unrecognised risk factors.

PATIENTS AND METHODS

We performed a multicentre, retrospective case-control study in Mexico between 1999 and 2014. We included a total of 168 patients who accounted for 77 episodes of PRES, as follows: SLE/PRES, 43 patients with 48 episodes; SLE without PRES, 96 patients; and PRES without SLE, 29 patients. SLE diagnosis was considered when patients fulfilled ≥4 American College of Rheumatology criteria. PRES was defined by reversible neurological manifestations and MRI changes.

RESULTS

Patients with SLE/PRES were younger, presented with seizures as the most common manifestation (81%) and 18% had the typical occipital MRI finding. Hypertension (OR=16.3, 95% CI 4.03 to 65.8), renal dysfunction (OR=6.65, 95% CI 1.24 to 35.6), lymphopenia (OR=5.76, 95% CI 1.36 to 24.4), Systemic Lupus Erythematosus Activity Index ≥ 6 points (OR=1.11, 95% CI 1.01 to 1.22) and younger age (OR=0.86, 95% CI 0.81 to 0.91, p<0.001) were independent risk factors for development of PRES in SLE. Furthermore, dyslipidemia also characterised the association between PRES and SLE (OR=10.6, 95% CI 1.17 to 96.4).

CONCLUSIONS

This is the largest reported series of patients with SLE and PRES. We were able to corroborate the known risk factors for of PRES, and found two previously undescribed factors (lymphopenia and dyslipidemia), which suggests that endothelial dysfunction is a key element in PRES pathogenesis in lupus patients.

A case of posterior reversible encephalopathy syndrome associated with acute pancreatitis and chronic alcoholism

Posterior reversible encephalopathy syndrome (PRES) is known to be caused by a variety of clinical disorders. The authors encountered a case of PRES associated with acute pancreatitis and chronic alcoholism. A 49-year-old man presented with altered mental status. Magnetic resonance imaging (MRI) displayed vasogenic edema at the bilateral posterior temporal and parieto-occipital lobes and cerebellum. Laboratory tests and abdominal computed tomography (CT) revealed acute pancreatitis. The patient recovered completely, and follow-up brain MRI and abdominal CT exhibited resolution of the previous lesions. We suggest that acute pancreatitis might be an etiology of PRES.

An unusual cause of altered mental status: the importance of monitoring a patient's blood pressure

A 73-year-old man presented to the emergency room for acute onset altered mental status. The initial work-up yielded no definitive cause. An MRI demonstrated lesions in the bilateral posterior occipital lobes (not noted on an earlier MRI obtained from an outside institution) that were suggestive of posterior reversible encephalopathy syndrome (PRES). He had a history of Parkinson's disease complicated by autonomic instability (wide blood pressure fluctuations) that was medically controlled in the outpatient setting. During the early course of his hospitalisation, he again displayed wide blood pressure fluctuations. After his blood pressure stabilised, his mental status eventually improved to baseline. A repeat MRI obtained demonstrated near-complete resolution of the previously noted lesions and confirmed the diagnosis of PRES.

Posterior reversible encephalopathy syndrome in a patient with a Chiari I malformation

Background:

The authors describe a unique case of a patient who developed posterior reversible encephalopathy syndrome (PRES) following postoperative treatment of a Chiari I malformation.

Case Decsription:

A 25-year-old female presented with complaints of left upper and lower extremity paresthesias and gait disturbances. A magnetic resonance imaging (MRI) of the brain and cervical spine showed a Chiari I malformation with tonsillar descent beyond the level of the C1 lamina. She underwent a suboccipital craniectomy and C1 laminectomy with cerebellar tonsillar cauterization and duraplasty. Postoperatively, an MRI showed bilateral acute infarcts of the cerebellar vermis. She was initially treated for cerebellar ischemia with hypertensive therapy with a subsequent decline in her neurologic status and generalized tonic–clonic seizure. Further workup showed evidence of PRES. After weaning pressors, the patient had a significant progressive improvement in her mental status.

Conclusion:

Although the mechanism of PRES remains controversial given its diverse clinical presentation, several theories implicate hypertension and steroid use as causative agents.

De novo malignancies after adult-to-adult living-donor liver transplantation with a malignancy surveillance program: comparison with a Japanese population-based study

BACKGROUND

Organ transplant recipients have an increased incidence of malignancy. Race differences in a variety of malignancies are observed among the general population, but de novo malignancies after adult-to-adult living-donor liver transplantation (LDLT) have not been compared with those from a Japanese population-based study.

METHODS

The subjects were 360 adult LDLT recipients who survived more than 1 year after transplantation. An annual medical checkup and screening examinations were performed as follows: abdominal computed tomography or magnetic resonance imaging, upper gastrointestinal endoscopy, and total colonoscopy and immunochemical fecal occult blood test every 1 to 2 years. Complete blood count, liver function tests, and several tumor markers were checked every 1 to 3 months after LDLT.

RESULTS

Mean follow-up period was 7.5±3.4 years. During the follow-up period, 27 de novo malignancies were diagnosed in 26 recipients. Colorectal cancer was the most commonly detected malignancy. The overall mortality of the recipients with de novo malignancies was similar to the findings of the Japanese general population-based study (standardized mortality ratio=0.9). Overall, the incidence of cancer was significantly higher in transplant recipients than in the Japanese general population (standardized incidence ratio=1.8). The 5-year estimated survival rate of recipients with de novo malignancies was 81% and those of recipients without malignancies was 93% (P<0.0001).

CONCLUSIONS

Colorectal malignancies predominated in Japanese liver transplant recipients. Although de novo malignancies correlated with a poor prognosis, the standardized mortality ratio was 0.9 compared with that of subjects of a Japanese population-based study.

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.

Posterior reversible encephalopathy syndrome could be an underestimated variant of "reversible neurological deficits" in Systemic Lupus Erythematosus

Background

Posterior reversible encephalopathy syndrome (PRES) has been increasingly identified in patients with systemic lupus erythematosus (SLE) owing to the advance in neuroimaging techniques. Prompt diagnosis is pivotal to improve its outcome. To analyze the clinical and radiographic profile of PRES in patients with SLE and search for the appropriate treatment strategy PRES in SLE.

Methods

SLE patients who fulfilled the diagnostic criteria for PRES from August 2008 to January 2011 were evaluated at baseline, and followed to determine clinical outcomes. Data were analysis on clinical characteristics, laboratory abnormalities, treatment details, and outcomes.

Results

Ten episodes of PRES in patients with SLE were identified. All patients were female, mean age of onset was 22.93 ± 2.48 years, and SLEDAI at the onset of PRES were 25.8 ± 5.7. All cases had acute onset of headache, altered mental status, stupor, vomiting, cortical blindness and seizures. Neurological symptoms were the initial manifestation of SLE in three cases. Head magnetic resonance imaging (MRI) demonstrated posterior white matter edema involving the parietal, temporal and occipital lobes, which were more conspicuous on T2 weighted spin echo and diffusion-weighted MR imaging (DWI) than on computed tomography (CT) scan. Complete clinical and radiographic recovery was observed in 8 patients after prompt treatment with corticosteroids.

Conclusions

PRES might be due to lupus per se besides other traditional causative factors such as hypertension. PRES might be an underestimated variant of “reversible neurological deficits” in SLE. Prompt recognition and timely management is important to prevent permanent neurological deficits.

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.

MR imaging findings of medulla oblongata involvement in posterior reversible encephalopathy syndrome secondary to hypertension

Although the combination of MR imaging findings and clinical evidence of hypertension may suggest the diagnosis of posterior reversible encephalopathy syndrome (PRES), MR imaging findings with only involvement of the medulla oblongata pose a diagnostic dilemma. In the cases presented here, we demonstrated MR imaging findings of a presumed brain stem (medulla oblongata) variant of PRES and emphasized the diagnostic value of diffusion-weighted imaging (DWI).

Reversible encephalopathy after cardiac transplantation: histologic evidence of endothelial activation, T-cell specific trafficking, and vascular endothelial growth factor expression

Reversible encephalopathy after transplantation is well recognized. The condition is commonly thought to be related to immune suppression, and a characteristic brain imaging pattern is typically recognized with vasogenic edema in the parietal and occipital regions, typically termed posterior reversible encephalopathy syndrome (PRES). We report the case of a patient with reversible encephalopathy after cardiac transplantation with brain biopsy evidence of endothelial activation, selective intravascular/perivascular T-cell trafficking, and VEGF expression in astrocytes, neurons, and the endothelium.

[Brainstem variant of reversible posterior leukoencephalopathy syndrome with a prolonged clinical course: a case report]

A 38-year-old man gradually developed gait instability, dysarthria, and dysphagia over two months associated with an elevated blood pressure after starting hemodialysis therapy for diabetic nephropathy. Brain MRI studies indicated vasogenic edema in the brainstem, extending from the lower midbrain to the upper medulla oblongata. The patient's high blood pressure was refractory to treatment, and his neurological disabilities and MRI abnormalities progressed. FDG-PET, MR spectroscopy, and cerebrospinal fluid studies did not suggest neoplastic pathologies. The patient was diagnosed with a brainstem variant of reversible posterior leukoencephalopathy syndrome, and received three courses of steroid pulse therapy. After the pulse therapy, the clinical manifestations and MR findings improved. By maintaining strict management of blood pressure and body water balance during hemodialysis, he did not experience any further clinical exacerbation, and the lesion on MR images continued to regress. Ten months after the pulse therapy, T1-weighted images showed slightly hyperintense signal. This case suggests that reversible posterior leukoencephalopathy syndrome (RPLS) may take a chronic clinical course without acute onset.

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.

Reversible posterior encephalopathy syndrome in systemic lupus erythematosus and lupus nephritis

Reversible posterior encephalopathy syndrome (RPES) is a clinical entity characterized with headache, nausea, vomiting, seizures, consciousness disturbance, and frequently visual disorders associated with neuroradiological findings, predominantly white matter abnormalities of the parieto-occipital lobes. The central nervous system manifestations of systemic lupus erythematosus (SLE) are highly diverse. However, SLE-associated RPES has been seldom reported. Here, we report a case with RPES in SLE and lupus nephritis with exclusive involvement of parietal and occipital cortices. A systematic review of the literature on the pathogenesis and treatment of SLE-associated RPES is included.

An autopsy case of drug-induced diffuse cerebral axonopathic leukoencephalopathy: the pathogenesis in relation to reversible posterior leukoencephalopathy syndrome

An autopsy case of diffuse axonopathic leukoencephalopathy induced by drug treatment is reported. A 70-year-old woman with multiple myeloma developed encephalopathy several days after completing a course of intravenous human immunoglobulin (IVIg) and granulocyte-colony stimulating factor (G-CSF), and died within I month. T2-weighted MRI demonstrated multifocal high-signal areas in the bilateral cerebral white matter, especially in the right frontal lobe. Neuropathologically, multifocal hydropic axonal swelling with a poor glial reaction was recognized diffusely in the bilateral deep cerebral white matter, being especially marked in the frontal lobe. The cortex, subcortical U-fibers, corpus callosum, and anterior commissure were spared. The cerebellar white matter also showed similar changes, albeit less marked, but the brainstem was spared. Microscopically, the myeloma involvement of the CNS was limited to the dura, and the cerebral arteries showed slight atherosclerosis, but neither thrombi nor angitis. This case, although ultimately fatal, neurologically and neuroradiologically resembled reversible posterior leukoencephalopathy syndrome (RPLS) induced by IVIg and/or G-CSF, and the nature and selective distribution of the neuropathological changes suggested that the pathogenesis involved vasospasm of the bilateral internal carotid artery and the main trunks of the cerebral arteries, due to unknown cause, inducing ischemia in the deep white matter, which is supplied by long nutrient arteries.

48 year old male with sudden onset of right sided weakness

This 48 year-old male presented with sudden right sided weakness and hypertension, and on CT was found to have a deep left hemispheric intracerebral hematoma. There were accompanying bilateral hypointensities in the occipital lobes, unchanged 1 day later, when expansion of the hematoma and uncal herniation resulted in death. The past medical history included liver transplantation followed by long term cyclosporin, features of thrombotic thrombocytopenic purpura (TTP) attributed to cyclosporin, type 1 diabetes mellitus and acute renal failure attributed to diabetic nephropathy. There was a 2-month history of hypertension poorly responsive to therapy. The occipital lobes at autopsy showed focal cortical hemorrhages with bilateral discoloration of white matter sparing subcortical zones. Microscopy showed white matter pallor with parenchymal cysts, enlarged perivascular spaces and focal acute hemorrhages consistent with edema secondary to acute hypertension. Cortical hemorrhages were associated with intravascular thrombi and fibrin exudates, as well as an accompanying microinfarct, attributed to TTP. The occipital pathology reflects the posterior leukoencephalopathy syndrome (PLS) combined with cortical lesions of TTP. PLS is usually diagnosed radiologically by occipital hypointensities, and is reversible, so that autopsy pathology is rarely examined. TTP may predispose to the development of the PLS in certain cases.

Reversible Posterior Leukoencephalopathy in Patients with Systemic Lupus Erythematosus

BACKGROUND

The development of central nervous system (CNS) symptoms in patients with preexisting systemic lupus erythematosus (SLE) evokes a wide differential diagnosis. Reversible posterior leukoencephalopathy (RPLE) is a rapidly evolving neurologic syndrome with characteristic clinical and radiographic features. Conditions commonly associated with RPLE include hypertensive encephalopathy, eclampsia, immunosuppressive drugs, and inflammatory disorders.

OBJECTIVES

To describe our experience with RPLE in patients with concomitant SLE and review the literature.

METHODS

The details of 5 novel cases and a MEDLINE review of the literature concerning the development of RPLE in association with SLE are presented.

RESULTS

All cases included patients with SLE who developed the acute onset of headache, altered mental status, visual changes, and seizures. Neuroimaging demonstrated posterior white matter edema involving the parietal, temporal, and occipital lobes. Complete clinical and radiographic recovery occurred with prompt antihypertensive treatment and supportive care. Literature review identified 16 additional cases of RPLE occurring in patients with active SLE; the majority of these reports was similar in presentation and outcome to our experience.

CONCLUSIONS

It is likely that the clinical manifestations and neuroimages in these lupus patients were the result of the RPLE syndrome. Fortunately, this cause of "secondary" CNS symptoms in patients with SLE is readily reversible when diagnosed early and treated with blood pressure control and supportive care.

Reversible posterior leukoencephalopathy syndrome: report of 2 simultaneous cases in children

Reversible posterior leukoencephalopathy syndrome (RPLS) is a rare complication of cancer chemotherapy. We have recently observed two cases occurred simultaneously in children receiving different chemotherapy regimens, for hepatoblastoma and acute lymphoblastic leukaemia, respectively. Both children presented with altered mental status, severe visual disturbances, headache, seizures, backpain and hypertension. Magnetic resonance imaging showed cortical and subcortical lesions especially in the occipital and parietal regions, strongly consistent with RPLS. Both patients completely recovered from their neuropsychologic deficits in about ten days only with anticonvulsant and antihypertensive therapy, and chemotherapy regimen was promptly restarted according to the planned protocol, without any neuropsychological sequela. A mild left midriasis was the only neurologic defect that persisted in the patient with acute lymphoblastic leukemia.

The use of cyclosporine in a boy with a prior episode of posterior encephalopathy

We report the case of a 12- year-old Japanese boy who was receiving cyclosporine (Cs A) for steroid-dependent nephrotic syndrome despite a prior episode of Cs A-associated posterior encephalopathy. At the third relapsing of nephrotic syndrome, Cs A was initiated. Eight days after the Cs A therapy, the boy was admitted to the University Hospital of Tsukuba because of generalized convulsion. Magnetic resonance imaging (MRI) showed hyperintense lesions involving the bilateral parieto-occipital region. Cs A was discontinued, and cyclophosphamide was started. The boy had a 6-month drug-free period after the cyclophosphamide treatment and then relapsed three more times in the following 5 months. As the prednisolone dosage could not be decreased to less than 2 mg/kg/48 h, the patient was re-challenged with Cs A 1 1/2 years later. Blood pressure and serum Cs A levels were measured frequently, an anti-hypertensive drug was given, and MRI was done four times to detect hyperintense lesions. He has been receiving Cs A for 9 months, and MRI has revealed no abnormalities. At the latest follow-up, dated 12 April 2004, he was in a remissive state of nephrotic syndrome. This is the first report of giving Cs A to a nephrotic child who had a previous history of Cs A-associated posterior encephalopathy.

Implications of post-gadolinium MRI results in 13 cases with posterior reversible encephalopathy syndrome

BACKGROUND

There is a relative lack of definitive information about the contrast-enhancement characteristics of lesions in posterior reversible encephalopathy syndrome (PRES).

OBJECTIVE

Evaluation of contrast-enhanced MRI findings in PRES with a special emphasis on pathophysiology of post-gadolinium behavior of these lesions.

MATERIALS AND METHODS

Contrast-enhanced 1.5 T MRI findings and relevant clinical data of the patients were retrospectively reviewed on 13 cases (six males, seven females; age range: 22-78; mean age 47). Although fluid attenuated inversion recovery (FLAIR) and diffusion-weighted MR images were considered for identification of the entity, primarily post-contrast T1-weighted MR images were searched for traces of enhancement in the lesions.

RESULTS

No definitely enhancing lesion was identified in the MR images obtained in 6-48 h after onset of symptoms (mostly headaches, seizures and cortical visual field deficits) in this series. Severity of disease indicated by small hemorrhages, confluence of lesions or progression to cytotoxic edema did not seem to alter this result. Typical lesion characteristics were consistent with vasogenic edema on FLAIR and diffusion MR images. Acute elevation of blood pressure on chronic hypertensive background was responsible in four, eclampsia in three, uremia with blood pressure fluctuations in three, and cyclosporine-toxicity in three cases.

CONCLUSION

Although occasional enhancing brain lesions have been reported in the literature on PRES, contrast-enhancement of lesions may be a factor of scan timing and underlying etiology. Prospective studies with larger series on PRES are required for better evaluation of contrast-enhancement in MRI with respect to scan timing, which in turn may help understand its pathophysiology better.

Reversible posterior leukoencephalopathy syndrome: a misnomer reviewed

Reversible posterior leukoencephalopathy is a syndrome of headache, seizures and visual loss, often associated with an abrupt increase in blood pressure. Prompt diagnosis and therapy with antihypertensives, anticonvulsants, removal of any offending medication and treatment of associated disorders is essential since early treatment might prevent progression to irreversible brain damage. We present six illustrative cases presenting to Christchurch Hospital and review the condition. All were hypertensive, two were receiving immunosuppressant therapy after transplantation and one chemotherapy. Only three made a full recovery. The term reversible posterior leukoencephalopathy is a misnomer as the condition is not always reversible, is not necessarily confined to the posterior regions of the brain and can affect both white and grey matter. Magnetic resonance imaging findings of increased T2 and fluid attenuated inversion recovery signal predominantly involving the posterior regions of the cerebral hemispheres should alert the clinician to the possibility of this diagnosis.

Cortical blindness: Clinical and radiologic findings in reversible posterior leukoencephalopathy syndrome

PURPOSE

To alert ophthalmologists to the recognition of cortical visual loss as the presenting feature in patients with reversible posterior leukoencephalopathy syndrome (RPLES). Unique radiologic findings are paramount to the diagnosis.

DESIGN

Interventional case report.

METHODS

A patient was seen with perioperative bilateral cerebral visual loss that was misinterpreted initially as an irreversible ischemic event. Further detailed analysis of the radiologic findings and clinical history led to the correct diagnosis.

MAIN OUTCOME MEASURES

Visual acuity and magnetic resonance imaging (MRI) of the brain.

RESULTS

Recognition of the correct diagnosis of RPLES led to the institution of antihypertensive therapy and recovery of normal vision.

CONCLUSIONS

The diagnosis of RPLES should be considered in all patients with acute cerebral visual loss, especially in the setting of recent surgery, blood transfusion, chemotherapy, immunosuppressant use, hypertension, eclampsia, or seizures. Prompt diagnosis requires close collaboration with a radiologist and an emergent MRI study, which ideally should include diffusion-weighted imaging with calculation of an apparent diffusion coefficient map. Differentiation from acute cerebral ischemia is important in order to avoid permanent visual loss by prompt and vigorous treatment of exacerbating factors such as intermittent hypertension. Prompt diagnosis will also help to avoid potentially dangerous invasive procedures such as thrombolytic therapy.

Reversible Leukoencephalopathy Syndrome Associated to Leukopenia in a Chronic Hemodialysis Patient

Reversible leukoencephalopathy syndrome (RLS) is a rare brain disorder, characterized by diffuse attenuation of cerebral white matter, which has been most commonly observed in transplant patients receiving calcineurin inhibitors or in patients with severe hypertension. We report an episode of RLS in a 22-year-old male patient on chronic hemodialysis with well-controlled moderate hypertension who presented with de novo headache and generalized seizures. Cranial magnetic resonance image (MRI) revealed multiple areas of increased signal intensity in the white matter on T2-weighed images which resolved spontaneously at subsequent MRIs. White blood cell count showed leucopenia with normal CD4 count at flow cytometry. A viral etiology could not be demonstrated. Reversible leukoencephaolopathy syndrome symptoms remitted within 72 h but leukopenia persisted over 10 months. The patient received a kidney transplant 15 months after RLS onset and has received cyclosporine since the second post-transplant day. No recurrence of RLS symptoms has been observed. The etiology of the MRI changes in the present case seemed not to be either vasogenic or cytotoxic.

Central and extrapontine myelinolysis following allogeneic peripheral haematopoietic progenitor cell transplantation. Favourable outcome in a patient with chronic myeloid leukaemia

A 48-year-old-man in the first chronic phase of chronic myeloid leukaemia developed a central nervous system complication on day +57 after HLA-identical peripheral blood progenitor cell (PBPC) transplantation. The clinical picture evolved to a reversible pseudobulbar palsy requiring mechanical ventilation. MRI examination disclosed lesions typical of central and extrapontine myelinolysis (CEPM), which disappeared on a repeat examination 20 days later. The patient had received cyclosporine A (CsA) as GVHD prophylaxis and severe hyponatremia was detected 7 days after the first neurological sign. CEPM has been described in alcohol-induced liver disease, following rapidly corrected hyponatremia and associated with CsA in orthotopic liver transplantation. This is the first reported case of CEPM in PBPC transplantation, and CsA seems to have played a role in the development of this very serious complication.

Sindrome de encefalopatia posterior reversível: relato de caso

A encefalopatia posterior reversível é uma síndrome aguda / subaguda geralmente causada pela encefalopatia hipertensiva, eclâmpsia, neurotoxicidade a ciclosporina-A, encefalopatia urêmica e púrpura trombocitopênica trombótica.. A maioria dos pacientes apresenta elevação acentuada dos níveis tensionais outros, níveis moderados ou normais. Os sintomas são progressivos e compreendem cefaléia, diminuição do nível de consciência, crises epilépticas e distúrbios visuais. A sintomatologia regride completamente se corrigidas em tempo as causas determinantes, caso contrário, podem instalar-se danos irreversíveis como a cegueira cortical e morte. A tomografia computadorizada (TC) e, sobretudo, a ressonância magnética (RM) contribuem para o diagnóstico. Tais métodos evidenciam edema da substância branca e cinzenta, principalmente das regiões parieto-occipitais. Os achados podem apresentar dificuldade no diagnóstico, hoje superado em parte, com a técnica de difusão pela RM, capaz de diferenciar edema citotóxico de vasogênico. Apresentamos um caso de encefalopatia posterior reversível decorrente de encefalopatia hipertensiva estudada com TC e RM.

Contrasting the neurologic complications of cardiac transplantation in adults and children

The objective of this study was to evaluate neurologic complications associated with cardiac transplantation and compare the neurologic complications seen in adults and children. As advances in immunology have led to longer survival times for cardiac transplant recipients (1- and 5-year survival rates have improved to 86% and 65%, respectively), a number of neurologic complications have emerged. We performed a 14-year retrospective review of all adults and children (<18 years old) who had orthotopic cardiac transplantation at either Indiana University Hospital or James Whitcomb Riley Hospital for Children. The rates of neurologic complications involving the central and peripheral nervous systems in adults and children were assessed for differences using the chi-square test and Fisher's exact test where appropriate. A total of 191 orthotopic cardiac transplants were performed from 1986 to 2000, with follow-up available for 184, including 107 adults and 77 children. Thirty-two of 107 (30%) adults experienced a total of 47 complications, with peripheral neuropathies being the most frequent complication. Eighteen of 77 (23%) children experienced a total of 22 complications, with seizures being the most frequent complication. Other complications occurring in both groups were cerebrovascular, infectious, encephalopathies, neoplasms, and "other." Neurologic complications in children and adults after orthotopic cardiac transplantation are similar in both incidence and type. However, peripheral neuropathies tend to occur more frequently in adults than in children (P = .04), and the types of complications in the immediate post-transplant period seem to differ.

Neurotoxicity of immunosuppressive drugs

The clinical profile of neurotoxicity caused by immunosuppression has changed. When toxic levels are reached, both cyclosporine and tacrolimus may produce a clinical spectrum that varies from tremor and acute confusional state to status epilepticus and major speech or language abnormalities. Coma has become an unusual manifestation. Magnetic resonance imaging has been better defined, and abnormalities may be more widespread than those in the posterior lobes. These white matter lesions are caused by vasogenic edema, but may lead to apoptosis and cytotoxic edema if exposure is prolonged. Recent evidence suggests inhibition of a drug-efflux pump and dysfunction of the blood-brain barrier by enhanced nitric oxide production.

Reversible posterior leucoencephalopathy syndrome associated with bone marrow transplantation

Reversible posterior leucoencephalopathy syndrome (RPLS) has previously been described in patients who have renal insufficiency, eclampsia, hypertensive encephalopathy and patients receiving immunosuppressive therapy. The mechanism by which immunosuppressive agents can cause this syndrome is not clear, but it is probably related with cytotoxic effects of these agents on the vascular endothelium. We report eight patients who received cyclosporine A (CSA) after allogeneic bone marrow transplantation or as treatment for severe aplastic anemia (SSA) who developed posterior leucoencephalopathy. The most common signs and symptoms were seizures and headache. Neurological dysfunction occurred preceded by or concomitant with high blood pressure and some degree of acute renal failure in six patients. Computerized tomography studies showed low-density white matter lesions involving the posterior areas of cerebral hemispheres. Symptoms and neuroimaging abnormalities were reversible and improvement occurred in all patients when given lower doses of CSA or when the drug was withdrawn. RPLS may be considered an expression of CSA neurotoxicity.

Posterior leukoencephalopathy syndrome

Posterior leukoencephalopathy syndrome is a newly recognised brain disorder that predominantly affects the cerebral white matter. Oedematous lesions particularly involve the posterior parietal and occipital lobes, and may spread to basal ganglia, brain stem, and cerebellum. This rapidly evolving neurological condition is clinically characterised by headache, nausea and vomiting, seizures, visual disturbances, altered sensorium, and occasionally focal neurological deficit. Posterior leukoencephalopathy syndrome is often associated with an abrupt increase in blood pressure and is usually seen in patients with eclampsia, renal disease, and hypertensive encephalopathy. It is also seen in the patients treated with cytotoxic and immunosuppressive drugs such as cyclosporin, tacrolimus, and interferon alfa. The lesions of posterior leukoencephalopathy are best visualised with magnetic resonance (MR) imaging. T2 weighted MR images, at the height of symptoms, characteristically show diffuse hyperintensity selectively involving the parieto-occipital white matter. Occasionally the lesions also involve the grey matter. Computed tomography can also be used satisfactorily to detect hypodense lesions of posterior leukoencephalopathy. Early recognition of this condition is of paramount importance because prompt control of blood pressure or withdrawal of immunosuppressive agents will cause reversal of the syndrome. Delay in the diagnosis and treatment can result in permanent damage to affected brain tissues.

Immunosuppressive-associated leukoencephalopathy in organ transplant recipients

Immunosuppressive-associated leukoencephalopathy is a significant complication of cyclosporine (CsA) or tacrolimus therapy. However, the precise time of onset, role of putative risk factors, differences, if any, in presentation in various types of organ transplantation and outcome of this entity, remain poorly defined. Fifty cases of immunosuppressive-associated leukoencephalopathy reported in the literature in organ transplant recipients, were reviewed. Of 50 cases, 31 occurred in liver, 8 in renal, 6 in lung, and 5 in heart transplant recipients. Median time to onset was 28 days (range 3-1512 days); 82% occurred within 90 days of transplantation. Lesions tended to occur earlier in the liver transplant recipients, compared with other organ transplant recipients (median 9 vs. 29 days, P=.19). Seizures 74%, altered mental status 50%, and visual abnormalities 28% were the most frequently presenting features. Ten percent of the patients had fever with no documented source of infection. Systemic hypertension (P=.001), and lesions in the presence of therapeutic drug levels (P=.11) were more likely to occur with CsA than tacrolimus. Neuroimaging and clinical abnormalities were reversible on cessation or reduction of CsA or tacrolimus in all but two cases. Resolution of neurologic signs/symptoms occurred a median of 4 days and neuroimaging abnormalities in a median of 20 days on reduction/cessation of the drug. Immunosuppressive-associated leukoencephalopathy is a unique entity that can usually be diagnosed on the basis of its distinctive time of onset, and clinical and neuroimaging characteristics, and it is potentially reversible if promptly diagnosed. Despite identical clinical presentation of this syndrome in the recipients of CsA and tacrolimus, above noted variations in risk factors suggest that a difference in pathophysiologic mechanism may exist.