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Cortisol dysregulation, neuroinflammation, and cerebrovascular dysfunction are biological processes that have been separately shown to be affected in Alzheimer's disease (AD). Here, we aimed to identify biomarker signatures reflecting these pathways in 108 memory clinic patients with subjective cognitive decline (SCD, N = 40), mild cognitive impairment (MCI, N = 39), and AD (N = 29). Participants were from the well-characterized Cortisol and Stress in Alzheimer's Disease (Co-STAR) cohort, recruited at Karolinska University Hospital. Salivary diurnal cortisol measures and 41 CSF proteins were analyzed. Principal component analysis was applied to identify combined biosignatures related to AD pathology, synaptic loss, and neuropsychological assessments, in linear regressions adjusted for confounders, such as age, sex, education and diagnosis. We found increased CSF levels of C-reactive protein (CRP), interferon γ-inducible protein (IP-10), thymus and activation-regulated chemokine (TARC), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in MCI patients. Further, markers of cortisol dysregulation (flattened salivary cortisol awakening response and flattened cortisol slope) correlated with increased levels of placental growth factor (PlGF), IP-10, and chitinase 3-like 1 (YKL-40) in the total cohort. A biosignature composed of cortisol awakening response, cortisol slope, and CSF IL-6 was downregulated in AD patients. Moreover, biomarker signatures reflecting overlapping pathophysiological processes of neuroinflammation and vascular injury were associated with AD pathology, synaptic loss, and worsened processing speed. Our findings suggest an early dysregulation of immune and cerebrovascular processes during the MCI stage and provide insights into the interrelationship of chronic stress and neuroinflammation in AD., (© 2024. The Author(s).)

The purpose of this study was to investigate whether the co-existence of global small vessel disease (SVD) burdens and Alzheimer's disease (AD) pathologies change hippocampal volume (HV) and cognitive function of mild cognitive impairment (MCI) subjects. We obtained MRI images, cerebrospinal fluid biomarkers (Aβ 1-42 and p-tau), and neuropsychological tests of 310 MCI subjects from ADNI. The global SVD score was assessed. We used linear regression and linear mixing effect to analyze the effects of global SVD burdens, AD pathologies, and their interactions (SVD*AD) on baseline and longitudinal HV and cognition respectively. We used simple mediation effect to analyze the influencing pathways. After adjusting for global SVD and SVD*AD, Aβ remained independently correlated with baseline and longitudinal HV (std β = 0.294, p = .007; std β = 0.292, p < .001), indicating that global SVD did not affect the correlation between Aβ and HV. Global SVD score was correlated with longitudinal but not baseline HV (std β = 0.470, p = .050), suggesting that global SVD may be more representative of long-term permanent impairment. Global SVD, AD pathologies, and SVD*AD were independently correlated with baseline and longitudinal cognitions, in which the association of Aβ (B = 0.005, 95% CI: 0.005; 0.024) and p-tau (B = -0.002, 95% CI: -0.004; -0.000) with cognition were mediated by HV, suggesting that HV is more likely to explain the progression caused by AD pathology than SVD. The co-existence of global SVD and AD pathologies did not affect the individual association of Aβ on HV; HV played a more important role in the influence of AD pathology on cognition than in SVD., (© 2023 Wiley Periodicals LLC.)

Background and Purpose: Case series indicating cerebrovascular disorders in coronavirus disease 2019 (COVID-19) have been published. Comprehensive workups, including clinical characteristics, laboratory, electroencephalography, neuroimaging, and cerebrospinal fluid findings, are needed to understand the mechanisms., Methods: We evaluated 32 consecutive critically ill patients with COVID-19 treated at a tertiary care center from March 9 to April 3, 2020, for concomitant severe central nervous system involvement. Patients identified underwent computed tomography, magnetic resonance imaging, electroencephalography, cerebrospinal fluid analysis, and autopsy in case of death., Results: Of 32 critically ill patients with COVID-19, 8 (25%) had severe central nervous system involvement. Two presented with lacunar ischemic stroke in the early phase and 6 with prolonged impaired consciousness after termination of analgosedation. In all but one with delayed wake-up, neuroimaging or autopsy showed multiple cerebral microbleeds, in 3 with additional subarachnoid hemorrhage and in 2 with additional small ischemic lesions. In 3 patients, intracranial vessel wall sequence magnetic resonance imaging was performed for the first time to our knowledge. All showed contrast enhancement of vessel walls in large cerebral arteries, suggesting vascular wall pathologies with an inflammatory component. Reverse transcription-polymerase chain reactions for SARS-CoV-2 in cerebrospinal fluid were all negative. No intrathecal SARS-CoV-2-specific IgG synthesis was detectable., Conclusions: Different mechanisms of cerebrovascular disorders might be involved in COVID-19. Acute ischemic stroke might occur early. In a later phase, microinfarctions and vessel wall contrast enhancement occur, indicating small and large cerebral vessels involvement. Central nervous system disorders associated with COVID-19 may lead to long-term disabilities. Mechanisms should be urgently investigated to develop neuroprotective strategies.

Background: The diagnostic workup of idiopathic normal pressure hydrocephalus (iNPH) can be challenging due to an overlap in symptoms and neuroimaging features with other disorders. Despite a growing interest, a cerebrospinal fluid (CSF) biomarker profile in iNPH has not yet been identified., Objective: To determine the CSF biomarkers with the greatest evidence for differentiating iNPH from the most common differential diagnoses, Alzheimer's disease (AD) and subcortical ischemic vascular disease (SIVD)., Methods: A systematic literature search was conducted in PubMed to identify relevant articles up to July 2018 using the following MESH-terms: "Cerebrospinal fluid", "diagnos*", "hydrocephalus, normal pressure". Relevant data were extracted to assess the risk of bias in the included studies., Results: Twenty-five studies including 664 patients with iNPH, 502 with AD, 57 with SIVD, 81 with other disorders, and 338 healthy controls (HC) were included. They investigated the diagnostic value of 92 CSF biomarkers. Most evidence existed for amyloid-β 42 (Aβ42), phosphorylated tau (p-tau), and total tau (t-tau) in iNPH versus AD and HC: Aβ42 did not differ between iNPH and AD, but was lower than in HC subjects. T-tau and p-tau were lower in iNPH versus AD on a level comparable to HC subjects. There was moderate or limited evidence for 62 and 88 biomarkers, respectively. Several plausible biases characterize the literature including small sample sizes and inconsistent diagnostic criteria., Conclusion: T-tau and p-tau may differentiate iNPH from AD and Aβ42 from HC. A combination of these biomarkers may improve the diagnostic accuracy in iNPH.

Introduction: Blood-brain barrier (BBB) breakdown is observed in older versus younger adults and in late-onset Alzheimer's disease versus age-matched controls, but its causes and consequences in aging are unclear. We tested the hypothesis that BBB breakdown is associated with cognitive decline and inflammation in nondemented elders., Methods: Cerebrospinal fluid and serum inflammatory markers were measured using sandwich immunoassays in 120 subjects. Least Absolute Shrinkage and Selection Operator-logistic regression selected cerebrospinal fluid and serum signatures that best classified BBB impairment defined by the cerebrospinal fluid albumin index ≥9. Linear regression examined changes in Clinical Dementia Rating sum of boxes as a function of BBB integrity at baseline., Results: Mean age was 70 years, mean Mini–Mental State Examination was 27, and BBB impairment was recorded in 13.5%. BBB breakdown was associated with cognitive decline (P = .015). Cerebrospinal fluid intercellular adhesion molecule-1, vascular endothelial growth factor, interleukin-8, serum amyloid A, macrophage derived chemokine, and gender generated an area under the curve of 0.95 for BBB impairment, and serum IL-16, VEGF-D, IL-15, and other variables generated an AUC of 0.92 for BBB impairment., Discussion: BBB breakdown is associated with more rapid cognitive decline. Inflammatory mechanisms, including cell adhesion, neutrophil migration, lipid metabolism, and angiogenesis may be implicated., (Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.)

Background: One of the crucial challenges for the future of therapeutic approaches to Alzheimer's disease (AD) is to target the main pathological processes responsible for disability and dependency. However, a progressive cognitive impairment occurring after the age of 70, the main population affected by dementia, is often related to mixed lesions of neurodegenerative and vascular origins. Whereas young patients are mostly affected by pure lesions, ageing favours the occurrence of co-lesions of AD, cerebrovascular disease (CVD) and Lewy body dementia (LBD). Most of clinical studies report on functional and clinical disabilities in patients with presumed pure pathologies. But, the weight of co-morbid processes involved in the transition from an independent functional status to disability in the elderly with co-lesions still remains to be elucidated. Neuropathological examination often performed at late stages cannot answer this question at mild or moderate stages of cognitive disorders. Brain MRI, Single Photon Emission Computed Tomography (SPECT) with DaTscan®, amyloid Positron Emission Tomography (PET) and CerebroSpinal Fluid (CSF) AD biomarkers routinely help in performing the diagnosis of underlying lesions. The combination of these measures seems to be of incremental value for the diagnosis of mixed profiles of AD, CVD and LBD. The aim is to determine the clinical, neuropsychological, neuroradiological and biological features the most predictive of cognitive, behavioral and functional impairment at 2 years in patients with co-existing lesions., Methods: A multicentre and prospective cohort study with clinical, neuro-imaging and biological markers assessment will recruit 214 patients over 70 years old with a cognitive disorder of AD, cerebrovascular and Lewy body type or with coexisting lesions of two or three of these pathologies and fulfilling the diagnostic criteria for dementia at a mild to moderate stage. Patients will be followed every 6 months (clinical, neuropsychological and imaging examination and collection of cognitive, behavioural and functional impairment) for 24 months., Discussion: This study aims at identifying the best combination of markers (clinical, neuropsychological, MRI, SPECT-DaTscan®, PET and CSF) to predict disability progression in elderly patients presenting coexisting patterns., Trial Registration: NCT02052947 .

Objective: To develop, replicate, and validate an MRI-based quantitative measure of both cerebrovascular and neurodegeneration in Alzheimer disease (AD) for clinical and potentially research purposes., Methods: We used data from a cross-sectional and longitudinal community-based study of Medicare-eligible residents in northern Manhattan followed every 18-24 months (n = 1,175, mean age 78 years). White matter hyperintensities, infarcts, hippocampal volumes, and cortical thicknesses were quantified from MRI and combined to generate an MRI measure associated with episodic memory. The combined MRI measure was replicated and validated using autopsy data, clinical diagnoses, and CSF biomarkers and amyloid PET from the Alzheimer's Disease Neuroimaging Initiative., Results: The quantitative MRI measure was developed in a group of community participants (n = 690) and replicated in a similar second group (n = 485). Compared with healthy controls, the quantitative MRI measure was lower in patients with mild cognitive impairment and lower still in those with clinically diagnosed AD. The quantitative MRI measure correlated with neurofibrillary tangles, neuronal loss, atrophy, and infarcts at postmortem in an autopsy subset and was also associated with PET amyloid imaging and CSF levels of total tau, phosphorylated tau, and β-amyloid 42. The MRI measure predicted conversion to MCI and clinical AD among healthy controls., Conclusion: We developed, replicated, and validated an MRI measure of cerebrovascular and neurodegenerative pathologies that are associated with clinical and neuropathologic diagnosis of AD and related to established biomarkers., (© 2018 American Academy of Neurology.)

Objective: To measure CSF levels of biomarkers reflecting microglia and astrocytes activation, neuroinflammation, and cerebrovascular changes and study their associations with the core biomarkers of Alzheimer disease (AD) pathology (β-amyloid [Aβ] and tau), structural imaging correlates, and clinical disease progression over time., Methods: The study included cognitively unimpaired elderly (n = 508), patients with mild cognitive impairment (MCI, n = 256), and patients with AD dementia (n = 57) from the longitudinal Swedish BioFINDER cohort. CSF samples were analyzed for YKL-40, interleukin (IL)-6, IL-7, IL-8, IL-15, IP-10, monocyte chemoattractant protein 1, intercellular adhesion molecule 1 (ICAM-1), vascular adhesion molecule 1 (VCAM-1), placental growth factor, and fms-related tyrosine kinase 1 (Flt-1). MRI data were available from 677 study participants. Longitudinal clinical assessments were conducted in control individuals and patients with MCI (mean follow-up 3 years, range 1-6 years)., Results: CSF levels of YKL-40, ICAM-1, VCAM-1, IL-15, and Flt-1 were increased during the preclinical, prodromal, and dementia stages of AD. High levels of these biomarkers were associated with increased CSF levels of total tau, with the associations, especially for YKL-40, being stronger in Aβ-positive individuals. The results were similar for associations between phosphorylated tau and YKL-40, ICAM-1, and VCAM-1. High levels of the biomarkers were also associated with cortical thinning (primarily in the precuneus and superior parietal regions) and with subsequent cognitive deterioration in patients without dementia as measured with Mini-Mental State Examination (YKL-40) and Clinical Dementia Rating Sum of Boxes (YKL-40, ICAM-1, VCAM-1 and IL-15). Finally, higher levels of CSF YKL-40, ICAM-1, and Flt-1 increased risk of development of AD dementia in patients without dementia., Conclusions: Neuroinflammation and cerebrovascular dysfunction are early events occurring already at presymptomatic stages of AD and contribute to disease progression., (Copyright © 2018 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)

Purpose of Review: Alzheimer's disease and cerebrovascular disease (CVD) commonly co-occur. Whether CVD promotes the progression of Alzheimer's disease pathology remains a source of great interest. Recent technological developments have enabled us to examine their inter-relationship using quantifiable, biomarker-based approaches. We provide an overview of advances in understanding the relationship between vascular and Alzheimer's disease pathologies, with particular emphasis on β-amyloid and tau as measured by positron emission tomography and cerebrospinal fluid (CSF) concentration, and magnetic resonance imaging markers of small vessel disease (SVD)., Recent Findings: The relationship between cerebral β-amyloid and various markers of SVD has been widely studied, albeit with somewhat mixed results. Significant associations have been elucidated, particularly between β-amyloid burden and white matter hyperintensities (WMH), as well as lobar cerebral microbleeds (CMB), with additive effects on cognition. There is preliminary evidence for an association between SVD and tau burden in vivo, although compared with β-amyloid, fewer studies have examined this relationship., Summary: The overlap between Alzheimer's disease and cerebrovascular pathologies is now being increasingly supported by imaging and CSF biomarkers, indicating a synergistic effect of these co-pathologies on cognition. The association of WMH and CMB with Alzheimer's disease pathology does not establish direction of causality, for which long-term longitudinal studies are needed.

Background: Alzheimer's disease (AD) pathology and hypertension (HTN) are risk factors for development of white matter (WM) alterations and might be independently associated with these alterations in older adults., Objective: To evaluate the independent and synergistic effects of HTN and AD pathology on WM alterations., Methods: Clinical measures of cerebrovascular disease risk were collected from 62 participants in University of Kentucky Alzheimer's Disease Center studies who also had cerebrospinal fluid (CSF) sampling and MRI brain scans. CSF Aβ1-42 levels were measured as a marker of AD, and fluid-attenuated inversion recovery imaging and diffusion tensor imaging were obtained to assess WM macro- and microstructural properties. Linear regression analyses were used to assess the relationships among WM alterations, cerebrovascular disease risk, and AD pathology. Voxelwise analyses were performed to examine spatial patterns of WM alteration associated with each pathology., Results: HTN and CSF Aβ1-42 levels were each associated with white matter hyperintensities (WMH). Also, CSF Aβ1-42 levels were associated with alterations in normal appearing white matter fractional anisotropy (NAWM-FA), whereas HTN was marginally associated with alterations in NAWM-FA. Linear regression analyses demonstrated significant main effects of HTN and CSF Aβ1-42 on WMH volume, but no significant HTN×CSF Aβ1-42 interaction. Furthermore, voxelwise analyses showed unique patterns of WM alteration associated with hypertension and CSF Aβ1-42., Conclusion: Associations of HTN and lower CSF Aβ1-42 with WM alteration were statistically and spatially distinct, suggesting independent rather than synergistic effects. Considering such spatial distributions may improve diagnostic accuracy to address each underlying pathology.

Background: Adipokines bearing the potential to cross the blood-brain barrier (BBB) are promising candidates for the endocrine regulation of central nervous processes and of a postulated fat-brain axis. Resistin and progranulin concentrations in paired serum and cerebrospinal fluid (CSF) samples of patients undergoing neurological evaluation and spinal puncture were investigated., Materials and Methods: Samples of n = 270 consecutive patients with various neurological diseases were collected without prior selection. Adipokine serum and CSF concentrations were measured by enzyme-linked immunosorbent assay and serum and CSF routine parameters by standard procedures. Anthropometric data, medication and patient history were available., Results: Serum levels of resistin and progranulin were positively correlated among each other, with respective CSF levels, low-density lipoprotein cholesterol levels and markers of systemic inflammation. CSF resistin concentrations were generally low. Progranulin CSF concentrations and CSF/serum progranulin ratio were significantly higher in patients with infectious diseases, with disturbed BBB function and with elevated CSF cell count and presence of oligoclonal bands. Both adipokines are able to cross the BBB depending on a differing patency that increases with increasing grade of barrier dysfunction. Whereas resistin represents a systemic marker of inflammation, CSF progranulin levels strongly depend on the underlying disease and dysfunction of blood-CSF barrier., Conclusions: Resistin and progranulin represent novel and putative regulators of the fat-brain axis by their ability to cross the BBB under physiological and pathophysiological conditions. The presented data provide insight into the characteristics of BBB function regarding progranulin and resistin and the basis for future establishment of normal values for CSF concentrations and CSF/serum ratios., (© 2015 Stichting European Society for Clinical Investigation Journal Foundation.)

Understanding inflammatory mechanisms in vascular dementia (VD) is pivotal for achieving better insights into changes in brain metabolism. We performed cytokine profiling and measured levels of the cellular prion protein (PrP(C)) in serum and cerebrospinal fluid (CSF) samples from patients with VD and with vascular encephalopathy (VE). Significant changes were observed for interleukin (IL)-1β, IL-4, IL-5, tumor necrosis factor alpha, interferon gamma, granulocyte-colony stimulating factor, monocyte chemotactic protein 1, and macrophage inflammatory protein 1 beta in serum and for IL-6 and granulocyte macrophage colony-stimulating factor in CSF of VD and VE patients, suggesting that most of immune markers depend on vascular lesions, while only IL-6 was related to dementia. In VD patients, the severity of dementia as defined by the Mini-Mental Status Test or Cambridge Cognitive Examination battery test was significantly correlated with the levels of IL-8 (CSF) and macrophage inflammatory protein 1 beta (serum and CSF). Additionally, in CSF of VD patients, our data revealed a correlation between immune and neurodegenerative marker proteins. Both indicate an association of neuroinflammation and cognitive decline. Levels of PrP(C) were regulated differentially in VD and VE patients compared with Alzheimer's disease patients and controls. Moreover, we observed a significant negative correlation between cytokine levels and PrP(C) in VD patients in CSF and serum, as well as a correlation between PrP(C) expression with levels of neurodegenerative marker proteins in CSF (in VD and VE patients). Our data suggest that immunological modifiers play a role in VD and VE patients and provide evidence for an association of PrP(C) with immune and neurodegenerative markers., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Reversible cerebral vasoconstriction syndrome (RCVS) is a disease of unclear incidence frequently affecting middle aged women and is usually associated with use of adrenergic or serotoninergic substances. The exclusion of relevant differential diagnoses, such as aneurysmal subarachnoid hemorrhage, primary cerebral angiitis, posterior reversible encephalopathy syndrome and carotid artery dissection is critical in terms of time and significance. Thunderclap headache as well as multiple and multilocular vasospasms with direct or indirect angiography without substantial findings in cerebrospinal fluid diagnostics are typical symptoms. The necessity for intensive care treatment is often justified by initial acute impairment of vital functions and possible development of cerebral or extracerebral complications. Because the exact pathophysiology remains unknown, a specific therapy does not exist. This poses significant challenges in intensive care medicine, which are illustrated on the basis of the case study presented.

Objective: Preclinical and post-mortem studies suggest that Alzheimer disease (AD) causes cerebrovascular dysfunction, and therefore may enhance susceptibility to cerebrovascular disease (CVD). The objective of this study was to investigate this association in a memory clinic population., Methods: The AD biomarkers CSF amyloid β42, amyloid β40 and APOE-ε4 status have all been linked to increased CVD risk in AD, and therefore the first aim of this study was to analyze the association between these biomarkers and CVD. In 92 memory clinic patients the cross-sectional association between AD biomarkersand the severity of CVD was investigated with linear regression analysis. Additionally, we studied whether AD biomarkers modified the relation between vascular risk factors and CVD. CVD was assessed on MRI through a visual rating scale.Analyses were adjusted for age. The second aim of this study was to investigate the association between clinical AD and CVD, where 'clinical AD' was defined as follows: impairment in episodic memory, hippocampal atrophy and an aberrant concentration of cerebrospinal fluid (CSF) biomarkers. 47 of the 92 patients had AD., Results: No association between CSF amyloid β42, amyloid β40 or APOE-ε4 status and CVD severity was found, nor did these AD biomarkers modify the relation between vascular risk factors and CVD. Clinical AD was not associated with CVD severity (p=0.83). Patients with more vascular risk factors had more CVD, but this relationship was not convincingly modified by AD (p=0.06)., Conclusions: In this memory clinic population, CVD in patients with AD was related to vascular risk factors and age, comparable to patients without AD. Therefore, in our study, the preclinical and post-mortem evidence that AD would predispose to CVD could not be translated clinically. Further work, including replication of this work in a different and larger sample, is warranted.

The neurochemical abnormalities underlying vascular parkinsonism (VP) have not been well characterised. A better understanding may help to optimize pharmacological interventions. Since VP patients generally have a poorer response to l-Dopa than Parkinson's disease (PD) patients, we investigated whether levels of relevant CSF neurotransmitter metabolites may be differentially altered in VP and PD and assessed the potential of neurotransmitter metabolites as biomarkers. We compared CSF levels of homovanillic acid (HVA), 5-hydroxyindolacetic acid, and 3-methoxy-4-hydroxyphenylethyleneglycol, in 16 VP patients, 57 PD patients and 60 non-neurological controls. We found that levels of HVA were reduced in PD compared with both VP and controls but did not differ significantly between VP and controls indicating that dopamine deficiency was less pronounced in VP.

Importance: Cerebrovascular disease and Alzheimer disease (AD) frequently co-occur and seem to act through different pathways in producing dementia., Objective: To examine cerebrovascular disease and AD markers in relation to brain glucose metabolism in patients with mild cognitive impairment., Design and Setting: Cohort study among the Alzheimer Disease Neuroimaging Initiative clinical sites in the United States and Canada., Participants: Two hundred three patients having amnestic mild cognitive impairment (74 of whom converted to AD) with serial imaging during a 3-year follow-up period., Main Outcomes and Measures: Quantified white matter hyperintensities (WMHs) represented cerebrovascular disease, and cerebrospinal fluid β-amyloid represented AD pathology. Brain glucose metabolism in temporoparietal and frontal brain regions was measured using positron emission tomography with fluorodeoxyglucose F18., Results: In converters, greater WMHs were associated with decreased frontal metabolism (-0.048; 95% CI, -0.067 to -0.029) but not temporoparietal metabolism (0.010; 95% CI, -0.010 to 0.030). Greater cerebrospinal fluid β-amyloid (per 10-pg/mL increase) was associated with increased temporoparietal metabolism (0.005; 95% CI, 0.000-0.010) but not frontal metabolism (0.002; 95% CI, -0.004 to 0.007) in the same patients. In nonconverters, similar relationships were observed except for a positive association of greater WMHs with increased temporoparietal metabolism (0.051; 95% CI, 0.027-0.076)., Conclusions and Relevance: The dissociation of WMHs and cerebrospinal fluid β-amyloid in relation to regional glucose metabolism suggests that these pathologic conditions operate through different and independent pathways in AD that reflect dysfunction in different brain systems. The positive association of greater WMHs with temporoparietal metabolism suggests that these pathologic processes do not co-occur in nonconverters.

Cerebrospinal fluid (CSF) flow dynamics, which supposedly have a strong relationship with chronic cerebrospinal venous insufficiency (CCSVI), might be expected to be affected in multiple sclerosis (MS) patients. In this study, CSF flow at the level of the cerebral aqueduct was evaluated quantitatively by phase contrast magnetic resonance imaging (PC-MRI) to determine whether CSF flow dynamics are affected in MS patients. We studied 40 MS patients and 40 healthy controls using PC-MRI. We found significantly higher caudocranial (p=0.010) and craniocaudal CSF flow volumes (p=0.015) and stroke volume (p=0.010) in the MS patients compared with the controls. These findings may support the venous occlusion theory, but may also be explained by atrophy-dependent ventricular dilatation independent of the venous theory in MS patients.

Authors report a case of a 35-year-old male with right-sided mild paresis, incontinence, dysexecutive syndrome, short-term memory loss and behavioral changes. Bilateral cerebral infarcts in the region of the caudate nuclei and the adjacent white matter were proved by brain MRI and multiple stenoses of the branches of Willis-circle were confirmed by MR angiography. Elevated protein level and pleocytosis were found in the cerebrospinal fluid with intrathecal IgG synthesis. Serum rapid plasma reagin, Treponema pallidum Particle Agglutination test, Treponema pallidum ELISA, liquor Venereal Disease Research Laboratory tests were positive. Meningovascular neurosyphilis was diagnosed. 24M U/day intravenous penicillin-G treatment was given for 14 days. The patient has vascular dementia due to the bilateral strategic infarcts disconnecting the prefrontal circuits; his symptoms are similar to general paresis. Laboratory and radiologic improvement was observed. Still, the patient have severe residual cognitive decline.

Background: Reversible cerebral vasoconstriction syndrome is characterized by thunderclap headache associated with multifocal vasoconstriction of cerebral arteries in patients without aneurysmal subarachnoid hemorrhage (SAH). The vasoconstriction reverts within three months. We report a 44-year-old man who had a thunderclap headache during sexual intercourse. A similar episode occurred at rest 36 hours later. The patient had already experienced a thunderclap headache 10 years earlier, during coitus. There were no abnormalities on examination. His brain computed tomography scan was normal and cerebrospinal fluid analysis showed no xanthochromia, 15 WBC/mm³ and 10 RBC/mm³. Lumbar puncture was repeated two days later (WBC = 3/mm³ and RBC = 43/mm³). An initial digital cerebral angiography showed a diffuse segmental intracerebral vasospasm. A new angiography after 15 days was normal. He remains headache-free after twenty six months. In conclusion, patients who have thunderclap headache with normal brain CT and cerebrospinal fluid without xantochromia should be investigated for this syndrome.

Based on the data on the current literature, the authors present the basic physiological and pathophysiological aspects of measurement of intracranial pressure and discuss indications for its monitoring and clinical value.

Chronic cerebrospinal venous insufficiency (CCSVI) is a vascular picture that shows a strong association with multiple sclerosis (MS). The aim of this study was to investigate the relationship between a Doppler cerebral venous hemodynamic insufficiency severity score (VHISS) and cerebrospinal fluid (CSF) flow dynamics in 16 patients presenting with CCSVI and relapsing-remitting MS (CCSVI-MS) and in eight healthy controls (HCs). The two groups (patients and controls) were evaluated using validated echo-Doppler and advanced 3T-MRI CSF flow measures. Compared with the HCs, the CCSVI-MS patients showed a significantly lower net CSF flow (p=0.027) which was highly associated with the VHISS (r=0.8280, r2=0.6855; p=0.0001). This study demonstrates that venous outflow disturbances in the form of CCSVI significantly impact on CSF pathophysiology in patients with MS.

We report a series of four patients with Susac's syndrome, which is characterized by the triad of visual loss due to branch retinal artery occlusions, sensorineural hearing loss due to cochlear involvement, and encephalopathy due to cerebral microangiopathy. However, as we describe in this series, the clinical triad may not be apparent for years, resulting in delays in diagnosis. We also report the variable cerebrospinal fluid and brain magnetic resonance imaging findings, and treatment using a combination of steroids and intravenous immunoglobulin, followed by mycophenolate mofetil.

Background: Varicella zoster virus (VZV) vasculopathy produces stroke secondary to viral infection of cerebral arteries. Not all patients have rash before cerebral ischemia or stroke. Furthermore, other vasculitides produce similar clinical features and comparable imaging, angiographic, and CSF abnormalities., Methods: We review our 23 published cases and 7 unpublished cases of VZV vasculopathy. All CSFs were tested for VZV DNA by PCR and anti-VZV IgG antibody and were positive for either or both., Results: Among 30 patients, rash occurred in 19 (63%), CSF pleocytosis in 20 (67%), and imaging abnormalities in 29 (97%). Angiography in 23 patients revealed abnormalities in 16 (70%). Large and small arteries were involved in 15 (50%), small arteries in 11 (37%), and large arteries in only 4 (13%) of 30 patients. Average time from rash to neurologic symptoms and signs was 4.1 months, and from neurologic symptoms and signs to CSF virologic analysis was 4.2 months. CSF of 9 (30%) patients contained VZV DNA while 28 (93%) had anti-VZV IgG antibody in CSF; in each of these patients, reduced serum/CSF ratio of VZV IgG confirmed intrathecal synthesis., Conclusions: Rash or CSF pleocytosis is not required to diagnose varicella zoster virus (VZV) vasculopathy, whereas MRI/CT abnormalities are seen in almost all patients. Most patients had mixed large and small artery involvement. Detection of anti-VZV IgG antibody in CSF was a more sensitive indicator of VZV vasculopathy than detection of VZV DNA (p < 0.001). Determination of optimal antiviral treatment and benefit of concurrent steroid therapy awaits studies with larger case numbers.

Blood-based tests for the differential diagnosis of Alzheimer's disease (AD) are under intensive investigation and have shown promising results with regard to Abeta40 and Abeta42 peptide species in incipient AD. Moreover, plasma Abeta40 was suggested as an independent cerebrovascular risk factor candidate. These considerations prompted us to analyse a total of 72 plasma samples in vascular dementias (VAD, n = 15), AD with cerebrovascular disease (AD with CVD, n = 7), AD (n = 15), Parkinson's disease and Parkinson's disease dementia (PD/PDD, n = 20) and 15 patients with depression that served as controls (DC) for distinct plasma amyloid-beta (Abeta) peptide patterns. For the analysis of plasma we used immunoprecipitation followed by the quantitative Abeta-SDS-PAGE/immunoblot. For comparison, CSF tau and Abeta1-42 analyses were performed. The major outcome was an increase in Abeta1-40 in plasma of VAD paralleled by a decrease in the ratio of Abeta1-38/Abeta1-40. The ratio Abeta1-38/Abeta1-40 in plasma enabled contrasts of beyond 85% and 80% for discriminating VAD from DC and all other patients, respectively. In CSF, we confirmed the typical CSF biomarker constellation of increased tau and diminished Abeta1-42 levels for AD. The diagnostic accuracy of plasma Abeta1-38/Abeta1-40 for VAD resembled the accuracy of CSF biomarkers for AD. From the presented results, we consider the ratio of plasma Abeta1-38/Abeta1-40 peptides to be a blood-based biomarker candidate for VAD.

Objective: To analyze a putative relationship between white matter lesions (WMLs), risk factors for WMLs, and Alzheimer disease (AD) as measured with the surrogate marker CSF Abeta42., Methods: The authors analyzed effects of acquired risk factors for cerebrovascular disease and WMLs on AD as measured with an intermediate marker, CSF Abeta42. A total of 127 consecutive patients with subjective memory impairment (mean age 66 years; 57 women) investigated at a university-based memory clinic had brain MRI scans. WMLs were rated on a 12-point scale with a semiquantitative procedure. They used path analysis with established and possible risk factors for WMLs and for reduced CSF Abeta42 (age, hypertension, hyperhomocysteinemia, hypercholesterolemia, APOE-epsilon4) as variables., Results: The WML score was 1.5 points higher (p < 0.05) in hypertensive than in nonhypertensive patients and 1.9 points higher (p < 0.05) in patients with hyperhomocysteinemia than in those with normal homocysteine levels. Hypercholesterolemia increased the probability of low CSF Abeta42 levels by 0.2 (p < 0.05). For each point increase in WML score, the probability of low CSF Abeta42 levels increased by 0.03 (p < 0.05). APOE-epsilon4 was associated with reduced CSF Abeta42 (p < 0.01)., Conclusion: Both hypercholesterolemia and white matter lesions may contribute to low CSF Abeta42 by independent mechanisms.

The contents of some trace elements such as zinc, copper, iron and cadmium in cerebrospinal fluid (CSF) of normal persons and the patients who suffered cerebral hemorrhage or infarction were determined directly by atomic absorption spectrometry. The method is simple and convenient with a recovery ratio by standard addition being 97.6% to 104.8%, and a relative standard deviation (RSD) is lower than 5%. The test showed that except for the content copper lower than normal, the patients suffering cerebrovascular disease have much higher contents of zinc, iron and cadmium. The result provides useful data for studying the relation between the contents of these trace elements and cerebrovascular disease, as well as diagnosing, treating and preventing this disease.

We present a case report of encephalopathy associated with Salmonella urbana infection in a child. A 5-year-old boy was admitted to our clinic with convulsions and coma. Cerebrospinal fluid (CSF) interleukin-6 (IL-6) and IL-8 were elevated at onset and were decreased within normal limit on the fifth day. Residual neurological deficits included severe mental deficits and spastic tetraplegia. High levels of CSF proinflammatory cytokines might be related to central nervous system (CNS) disease activity. Although encephalopathy is a rare complication of non-typhi Salmonella infection, it should be borne in mind as an occasionally serious and potentially lethal disease.

Aim: To evaluate S-100 and neuro specific enolase (NSE) levels in cerebrospinal fluid (CSF) from patients with differents neurological disorders in order to study possible differences in their protein concentrations., Material and Methods: We analysed samples of CSF taked by spinal puncture in subjects either from of the Casualty Department or from the Department of Neurology. Patients displaying neurological symptoms capable of being diagnostically tested. The total number of patients-samples examined was 43 (23 males and 20 females; mean age 43 y, range 1-78 y). Five patients groups were studied: a control group, meningitis, dementia, polyneuropathy-motorneuron disease, and acute cerebral infarction group (ACV). S-100 and NSE concentrations were measured by immunoradiometric procedures., Results: Highest S-100 median levels in CSF were found in dementia and ACV group, with elevate concentrations in meningitis groups. The increased S-100 levels in these groups was significant compared with control group (Mann-Withney U test). For NSE concentrations, there is a significant differences between dementia group and control group. No other significant differences were found between groups. There were positive correlation between S-100 levels and total protein., Conclusion: Our results suggest that S-100 and NSE can be a sensitive marker of brain damage in different neurological disorders. However, levels must be considered individually, since these concentrations depend on several factors, such as age, severity of brain damage or interval between the onset of brain damage and the taking of the sample.

Background: This article reports the results of research into the activities of lactic acid concentrations in the body fluids of children with progressive encephalopathies (PE) in comparison to patients with non-progressive encephalopathies (NPE) and those with non-progressive encephalopathies with concomitant epilepsy (NPEE). The study was designed to determine whether there is difference between the serum and CSF lactic acid concentrations in children with progressive encephalopathies (PE), static (non-progressive) encephalopathies (NPE) and non progressive encephalopathies with concomitant epilepsy (NPEE), and whether the clinical status correlates with the concentration of these biochemical markers in children with PE., Material/methods: The assessment involved 138 children of both sexes, whose age ranged between 8 months and 15 years, diagnosed and treated in the Neurology Department at the Pediatric Clinic of the Silesian Medical Academy in Katowice between 1995 and 1997. Lactate concentrations were determined in serum and cerebro-spinal fluid and analyzed statistically., Results: The findings showed higher serum and CSF concentrations in children with PE than in patients who manifested non-progressive forms of encephalopathy. The degree of clinical symptom aggravation in PE children was likewise analyzed and compared to the values of lactate concentrations in body fluids; however, no correlation was found between these parameters., Conclusions: Children with progressive encephalopathies present higher lactate concentrations in serum and cerebrospinal fluid than patients with static (non-progressive) encephalopathy.

Tau protein (tau) is primarily localised in neurons, and after brain parenchymal damage its release into cerebrospinal fluid (CSF) is increased. The particular influences of blood-CSF barrier function and of disease topography on CSF tau levels have not been studied yet. CSF tau concentrations determined by enzyme-immunoassay in various neurological diseases (n = 61) were not dependent upon blood-CSF barrier dysfunction. Significant elevation of tau levels in patients with meningoencephalitis and cerebral hemorrhage indicates brain parenchymal damage. In contrast, tau levels remained normal in patients with bacterial meningitis if encephalitic complications did not occur. In patients with Guillain-Barré syndrome tau levels were low. Increased tau levels in active multiple sclerosis compared to clinically nonactive states indicate axonal pathology in active disease.

Background and Purpose: Although activation of the N-methyl-D-aspartate (NMDA) receptor is thought to contribute to altered cerebrovascular regulation after traumatic brain injury, the effects of such injury on the vascular response to NMDA itself has been less well appreciated. The newly described opioid nociceptin/orphanin FQ (NOC/oFQ) elicits pial artery dilation, at least in part, in a prostaglandin-dependent manner and is released into cerebrospinal fluid after fluid percussion brain injury (FPI). Generation of superoxide anion (O(2)(-)) occurs after FPI, and a byproduct of cyclooxygenase metabolism is the generation of O(2)(-). This study was designed to determine whether NOC/oFQ generates O(2)(-), which in turn could link NOC/oFQ release to impaired NMDA-induced pial artery dilation after FPI., Methods: Injury of moderate severity (1.9 to 2.1 atm) was produced by the lateral FPI technique in anesthetized newborn pigs equipped with a closed cranial window. Superoxide dismutase-inhibitable nitroblue tetrazolium (NBT) reduction was determined as an index of O(2)(-) generation., Results: Under non-brain injury conditions, topical NOC/oFQ (10(-)(10) mol/L, the concentration present in cerebrospinal fluid after FPI) increased superoxide dismutase-inhibitable NBT reduction from 1+/-1 to 20+/-3 pmol/mm(2) but had no effect itself on pial artery diameter. Indomethacin (5 mg/kg IV) blunted such NBT reduction (1+/-1 to 6+/-2 pmol/mm(2)), whereas the NOC/oFQ receptor antagonist [F/G] NOC/oFQ (1-13) NH(2) (10(-)(6) mol/L) blocked NBT reduction. [F/G] NOC/oFQ (1-13) NH(2) and indomethacin also blunted the NBT reduction observed after FPI (1+/-1 to 15+/-1 versus 1+/-1 to 4+/-1 versus 1+/-1 to 4+/-1 pmol/mm(2) for sham, NOC/oFQ antagonist, and indomethacin-treated animals, respectively). NMDA (10(-)(8) and 10(-)(6) mol/L)-induced pial artery dilation was reversed to vasoconstriction after FPI, and [F/G] NOC/oFQ (1-13) NH(2) attenuated such vasoconstriction (sham 9+/-1% and 16+/-1% versus FPI -7+/-1% and -12+/-1% versus FPI-[F/G] NOC/oFQ (1-13) NH(2)-pretreated animals -2+/-1% and -3+/-1%). Indomethacin and the free radical scavengers polyethylene glycol superoxide dismutase and catalase also partially restored NMDA-induced vasodilation., Conclusions: These data show that NOC/oFQ, in concentrations present in cerebrospinal fluid after FPI, increased O(2)(-) production in a cyclooxygenase-dependent manner and contributes to such production after FPI. These data show that NOC/oFQ contributes to impaired NMDA-induced pial artery dilation after FPI. Therefore, these data suggest that cyclooxygenase-dependent O(2)(-) generation links NOC/oFQ release to impaired NMDA-induced cerebrovasodilation after brain injury.

Objective: The intravenous administration of tromethamine (INN, trometamol) lowers the intracranial pressure in patients with brain edema. One postulated mechanism of action is the increase of the pH of the cerebrospinal fluid., Methods: To study tromethamine kinetics in serum and cerebrospinal fluid, nine patients with external ventriculostomies and normal serum creatinine values received 60 mmol intravenous tromethamine (Tris 36.34%, pH 11) over 30 minutes. Serum and cerebrospinal fluid were drawn repeatedly, and concentrations were determined by HPLC., Results: Maximum serum concentrations (Cmax) ranged from 211 to 426 mg/L (median, 302 mg/L). The volume of distribution was 0.34 to 0.86 L/kg body weight (median, 0.53 L/kg), and the elimination half-life in serum (t1/2beta) 3.22 to 8.44 hours (median, 4.53 hours). Cerebrospinal fluid Cmax values ranging from 0.68 to 34.14 mg/L (median, 3.88 mg/L) were observed 1 to 12 hours after the end of the tromethamine infusion (median, 2 hours). AUC(CSF)/AUC(S) as a measure of overall cerebrospinal fluid penetration was 0.015 to 0.46 (median, 0.068). Cerebrospinal fluid Cmax and AUC(CSF)/AUC(S) depended on the function of the blood-cerebrospinal fluid barrier. Cerebrospinal fluid t1/2 (8.52 to 14.2 hours; median, 11.2 hours) was substantially longer than the t1/2beta in serum. In vitro, cerebrospinal fluid concentrations < or =30 mg/L did not influence cerebrospinal fluid pH., Conclusion: Tromethamine cerebrospinal fluid concentrations will be high enough to increase the pH of the cerebrospinal fluid only at large doses and in patients with a pronounced disruption of the blood-cerebrospinal fluid barrier.

Acetylcholinesterase (AChE), choline, monoamine and its metabolite, amino acid and superoxide dismutase (SOD) levels were measured in cerebrospinal fluid (CSF) in patients with cerebrovascular diseases. Patients were classified into the following four groups; controls: normal subjects without neurological disease, group A: cerebral hemorrhage, group B: cerebral infarction, group C: patients with mental impairment, including those in groups A and B, and a low score on Hasegawa's Dementia Rating Scale. CSF AChE level of groups A, B and C was decreased significantly, while choline concentration from patients showed a increase compared with that of control cases. CSF alanine concentration showed a tendency to increase, while glycine and glutamate tended to decrease. CSF epinephrine, norepinephrine or 3-methoxy-4-hydroxyphenylethylen glycol concentrations of groups A, B and C did not exhibit a significant difference from that in control cases. Some cases with cerebrovascular diseases showed low concentrations of both CSF 5-hydroxyindole acetic acid and homovanillic acid. However, dihydroxyphenyl acetic acid concentration was higher than in control cases. The CSF SOD level was not significantly from that in control cases. The changes in neurochemical substances in the CSF support their use as markers of cerebrovascular disease-related change.

Background and Purpose: The neuronal death that accompanies an ischemic stroke has previously been attributed to a necrotic process. However, numerous studies in experimental models of ischemia have recently indicated that programmed cell death, also called apoptosis, may contribute to neuronal death. The aim of the present study was to investigate the intrathecal levels of proteins regulating apoptosis in acute stroke and to relate these levels to brain damage and to production of proinflammatory and anti-inflammatory cytokines., Methods: Thirty stroke patients were studied prospectively on days 0 to 4, 7 to 9, 21 to 26, and after day 90 with clinical evaluation, radiological assessment, and analysis of cerebrospinal fluid (CSF) levels of soluble (s) Fas/APO-1 and sbcl-2, 2 proteins that regulate apoptosis. In addition, analysis of the intrathecal levels of cytokines interleukin (IL)-1beta, IL-6, IL-8, IL-10, granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor-alpha was performed. Nineteen CSF samples from healthy subjects were used for control purposes. The patients were examined with MRI 1 to 3 months after stroke onset for measurement of infarct volume, Results: Significantly decreased CSF levels of sFas/APO-1 were observed during the entire observation period, with a maximal decrease on day 21 after the onset of stroke. The intrathecal levels of sFas/APO-1 were significantly negatively correlated with the volume of brain infarct and with the neurological deficit 3 weeks and 3 months after the onset of the stroke. In addition, the intrathecal levels of sFas/APO-1 were significantly correlated with the levels of IL-1beta, IL-6, IL-10, and GM-CSF 3 weeks after the onset of the disease. The intrathecal levels of sbcl-2 were significantly decreased during the first 3 days after stroke onset and at the same time were positively correlated with the levels of IL-6 and tumor necrosis factor-alpha., Conclusions: Our study demonstrates decreased intrathecal levels of proteins with antiapoptotic properties, suggesting that patients with acute stroke display a propensity toward apoptosis. Control of factors regulating apoptosis may lead to decreased delayed brain damage in stroke.

Inflammation of multiple sclerosis (MS) brain and spinal cord tissue consists of macrophages, T lymphocytes and cytokines as well as B lymphocytes and immunoglobulins (IgGs). IgG can be detected in high concentrations in both central nervous system tissue and cerebrospinal fluid (CSF). Using a sensitive radioimmunoassay (RIA), autoantibodies to myelin basic protein (anti-MBP) can be detected in the CSF of 90-95% of MS patients with active disease. The purpose of the present report was to determine whether these same autoantibodies can be reliably detected in non-MS patients. Between 1978 and 1998, CSF was collected from 1,968 control non-MS patients with psychiatric, inflammatory and noninflammatory neurological diseases as well as nonneurological systemic diseases, and anti-MBP were measured by the same RIA used to detect anti-MBP in MS CSF. Anti-MBP were undetectable in 98% of CSF samples from non-MS controls. In the remaining 2% of control samples, CSF IgGs capable of binding to MBP in vitro were unpredictably detected. This latter group included 1% of patients with miscellaneous diseases such as encephalomyelitis, 5 siblings with familial spastic paraparesis, rare patients with strokes, Wernicke-Korsakoff's syndrome, inherited leukodystrophy, motor neuron disease and some patients with miscellaneous spinal cord diseases. An additional 1% of patients included a group with neurological symptoms suggestive of early or predisseminated MS. The high prevalence of free and/or bound anti-MBP in the CSF of MS patients and the rare and unpredictable occurrence in the CSF of non-MS patients suggest that autoimmunity to MBP may be operative in the demyelination of MS. Molecular clones of anti-MBP with specificity towards variable surface or cryptic MBP epitopes in vivo may determine whether or not they are involved in the demyelinating process, and this variability may also be present within the MS population. Potential mechanisms of anti-MBP-mediated demyelination in MS patients are discussed.

Tau protein levels in cerebrospinal fluid (CSF-tau) were determined in 29 patients with old cerebrovascular disease (CVD, 21 demented and eight non-demented), 69 patients with Alzheimer's disease (AD) and 17 age-matched normal controls. The CSF-tau level in the vascular dementia (VD) group (24.0 +/- 17.0 pg/ml) was significantly lower (P < 0.0001) than that in the AD group (90.0 +/- 45.3 pg/ml), but not significantly different from that in the non-demented patients with CVD (18.1 +/- 10.2 pg/ml) or controls (20.3 +/- 13.0 pg/ml). Among the VD patients, 1/21 exceeded a cut-off value (mean +/- 2 SD of controls), whereas 8/69 of the AD patients had CSF-tau levels below this value. These findings suggest that VD constitutes a group of dementias that can be separated from AD by normal CSF-tau levels. CSF-tau determinations in combination with other clinical findings may provide another diagnostic aid in the differential diagnosis between VD and AD.

Magnesium concentration in blood serum and cerebrospinal fluid (CSF) was determined in 131 patients aged from 21 to 91 years, with RIND, complete stroke, cerebral haemorrhage and control group. Magnesium was estimated by the use of colorimetry and the method of Mann and Yoe. The results are presented in figures. Statistical evaluations revealed significant decrease of magnesium concentrations in blood serum and CSF in ischaemic stroke compared with control group. In complete stroke significantly lower concentrations of magnesium in blood serum and CSF were found compared with RIND. In ischaemic stroke higher MgSER/MgCSF index was found compared with control group. Magnesium concentration in blood serum was not statistically different within 2 weeks of the disease. No relationships were found between blood serum or CSF Mg concentrations and gender or age.

A 55-year-old woman, who had two episodes of difficulty in putting a key into a keyhole probably due to optic ataxia at age 52 and 54 years old, developed speaking errors and was admitted to our hospital. She was 152.5 cm in height and 52.5 kg in weight. Neurological examination revealed right homonymous hemianopsia and sensory aphasia. A CSF examination revealed lymphocytic pleocytosis of 88/microliter. Serum lactate and pyruvate were remarkably increased after an aerobic exercise test. A few ragged-red fibers were present in the biopsied brachial biceps muscle. Brain MRI by FLAIR method showed scattered high signal lesions in the left temporal lobe, bilateral parieto-occipital lobes, left insular cortex and left thalamus. The left superficial temporal lesion was enhanced by gadolinium-DTPA. The proton MRS demonstrated the lactic acid peak as well as the decrease of NAA/choline ratio (0.38) in the left parieto-occipital region. Thus, she was diagnosed as a case of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) and successfully treated with ubidecarenone (150 mg/day). Six months later, she again developed seizure, right hemiparesis and deterioration of aphasia and presented again CSF lymphocytic pleocytoses of 15/microliter. Brain MRI demonstrated new lesions in the left temporoparietal lobes, left insular cortex and left corona radiata. Therefore, CSF pleocytosis appeared to be associated with stroke-like episodes in this case. Although the mechanism of CSF pleocytosis remains to be elucidated, it may involve the breakdown of blood-brain barrier caused by mitochondrial dysfunction. Otherwise, an inflammatory process similar to that in cases of Leber disease, who developed multiple sclerosis-like additional lesions in the central nervous system, may also take place in MELAS.

We have determined ammonia in cerebrospinal fluid (CSF) with the indophenol direct method. The results were compared with an enzymatic method. The method is very simple, and precision (coefficient of variation 1.6%) and linearity (r = 0.9999, p < 0.001) of the method are excellent. The recoveries of the method are very good (within-sample recovery: range 88-93, median 93%; between-sample recovery: 88-93, median 91%). In a population of 23 neurological patients not suffering from liver disease, the reference values ranged from 8 to 26, median 18 microM. Males and females did not differ (p = 0.5). The values obtained with the indophenol method were equal to the enzymatic method (range 9-28, median 18 microM, p = 0.6). On storage in the deep freeze (-20 degrees C), there was no change in CSF ammonia concentration for at least 1 mo. When stored at 4 degrees C (refrigerator), ammonia determinations have to be performed within 2 d. CSF storage at room temperature results in artificially elevated ammonia levels and should be avoided.

Background: We have recently described the induction of anti-cytokine autoantibodies during bacterial infections and autoimmune diseases as a mechanism for cytokine regulation., Methods: Herein, we study the occurrence of autoantibodies to pro- and anti-inflammatory cytokines in cerebrospinal fluid and plasma from patients with multiple sclerosis, aseptic meningitis and stroke., Results: Increased levels of autoantibodies to interferon gamma, tumour necrosis factor alpha, interleukin 4 and interleukin 10 were detected in both compartments of multiple sclerosis and aseptic meningitis patients. Interestingly, in cerebrospinal fluid from stroke patients, only autoantibodies to interleukin 4 and interleukin 10, but not interferon alpha or tumour necrosis factor alpha were detected. No significant autoantibody levels were registered in plasma from stroke patients against all four cytokines compared with healthy control subjects. The latter revealed very low autoantibody levels in plasma and no detectable autoantibodies in cerebrospinal fluid., Conclusions: Our data show for the first time the occurrence of cytokine autoantibodies in these diseases, but their biological significance is unclear.

To investigate the role of erythropoietin (EPO) in the central nervous systems, we assayed EPO concentrations in the cerebrospinal fluid (CSF) of patients with depression or old cerebrovascular injuries and controls. Concentrations of EPO in the CSF were significantly higher in 13 patients with depression (3.21+/-0.46 mU/mL) than in 10 patients with old cerebrovascular diseases (1.80+/-0.32 mU/mL, P < 0.01), and in 10 healthy controls (0.98+/-0.26 mU/mL, P < 0.01). Serum EPO concentrations did not differ among these three groups. In the patients with depression, 5 months of treatment with imipramine and/or nortriptyline significantly reduced EPO concentrations in the CSF (1.56+/-0.34 mU/ mL, P < 0.01). Results suggest that the brain of patients with depression may be in an hypoxic state, and that the increased EPO in the CSF may act to limit hypoxia-induced damage to neurons in these patients.

A growing body of evidence points out the potential role of inflammatory mechanisms in the pathophysiology of ischaemic brain damage. We have recently demonstrated that stroke patients display an intrathecal production of proinflammatory cytokines, such as IL-1beta and IL-6 already within the first 24 h after the beginning of symptoms (Tarkowski et al., 1995). The aim of the present study was to investigate patterns of local inflammatory responses as a consequence of acute stroke. Thirty stroke patients were studied prospectively on days 0-3, 7-9, 21-26 and after day 90 with clinical evaluations, radiological assessments and analysis of cerebrospinal fluid (CSF) cytokine levels. In addition, 15 healthy control CSF samples were used. Significantly increased CSF levels of IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-10 were observed early during the stroke with a peak on day 2 for the proinflammatory cytokines IL-8 and GM-CSF, and on day 3 for the immunoregulatory cytokine IL-10. Patients with a brain infarct predominantly located in the white matter showed significantly higher levels of IL-8 in CSF than patients with an infarct mainly located in the grey matter. Also, high levels of intrathecal tumour necrosis factor-alpha (TNF-alpha) were associated with the presence of white matter disease. Our study demonstrates an intrathecal production of proinflammatory and immunoregulatory cytokines in patients with stroke, supporting the notion of localized immune response to the acute brain lesion. A better understanding of the inflammatory response in stroke may lead to new treatment strategies.

Background and Purpose: Endothelin 1 (ET-1), a highly potent endogenous vasoactive peptide, exerts a sustained vasoconstrictive effect on cerebral vessels. Elevation of ET-1 in plasma has been reported 1 to 3 days after ischemic stroke. Since we assumed that a much faster and more intense response may be observed in the cerebrospinal fluid (CSF) and since an increase in concentration of ET-1 in the CSF may cause constriction of cerebral vessels and eventually influence the neurological outcome, we measured ET-1 values in the CSF within 18 hours of stroke onset and compared the values with those in the plasma., Methods: Twenty-six consecutive patients with acute stroke were clinically evaluated according to the modified Matthew Scale and underwent two repeat CT scans. Within 5 to 18 hours of stroke onset, lumbar puncture and blood samples were concomitantly obtained and tested; ET-1 levels in CSF and plasma of these patients were analyzed by radioimmunoassay and compared with the levels of a control group of patients with no neurological disease., Results: The mean CSF concentration of ET-1 in the CSF of stroke patients was 16.06 +/- 4.9 pg/mL, compared with 5.51 +/- 1.47 pg/mL in the control group (P < .001). It was significantly higher in cortical infarcts (mean, 17.7 +/- 4.1 pg/mL) than in subcortical lesions (mean, 10.77 +/- 4.1 pg/mL) (P < .001) and significantly correlated with the volume of the lesion (P = .003). The correlation between ET-1 levels in the CSF and the Matthew Scale score was less significant (P = .05). Plasma ET-1 level was not elevated in any group., Conclusions: ET-1 is found to be significantly elevated in the CSF of stroke patients during the 18 hours after stroke. No elevation was demonstrated in plasma at this time period. ET-1 may be used as an additional indicator of ischemic vascular events in the early diagnosis of stroke. The dissimilarity between the CSF and plasma ET-1 concentrations may lead also to an hypothesis that there is a vasoconstrictive effect on the cerebral vessels or a neuronal effect caused by ET-1 in the mechanism of the progression of brain ischemia.

The aim of the study was to evaluate gangliosides and sulfatide in cerebrospinal fluid (CSF) as markers for neuronal degeneration, gliosis, and demyelination in leukoaraiosis (LA). Lumbar CSF samples were taken from 37 elderly subjects with LA on computed tomography (CT). Patients with other pathology than LA or infarction on CT were excluded. In addition, CSF samples were collected from 16 elderly reference subjects without any neurological disease. Gangliosides GM1, GD1a, GD1b, GT1b, GD3, and sulfatide were determined. This concentration of the individual gangliosides and sulfatide showed no correlation with age. Gangliosides GD1b, GT1b, and GD3 were elevated in patients with mild LA compared to controls and patients with moderate or severe LA. GD1a was elevated in patients with mild LA compared to those with moderate LA. The concentration of sulfatide did not differ between the groups. When the patients were grouped in accordance to whether they had had cerebral infarction or not, differences between the groups were not found in the concentrations of any gangliosides and sulfatide. In conclusion, the analysis of CSF markers suggests that neuronal degeneration and gliosis predominate in the early stage of LA.

Background and Purpose: High levels of glutamate in plasma and cerebrospinal fluid (CSF) have been demonstrated in patients with acute ischemic stroke. The duration of this excitatory amino acid release has not been studied, and therefore the window of opportunity of treatment with glutamate antagonists is unknown. The aim of this investigation was to study the duration of the glutamate increase in patients with stable and progressing ischemic stroke., Methods: Glutamate in CSF was measured by high-performance liquid chromatography in 184 patients with an acute cerebral infarction of less than 24 hours' duration and in 43 control subjects., Results: Among the 120 patients with stable ischemic stroke, median glutamate levels were significantly lower- and within the reference range of control subjects-in those patients studied 6 to 24 hours from onset of symptoms than in patients studied in the first 6 hours (3 [range, 2 to 10] versus 5 mumol/L [range, 2 to 17]; P < .0001). In 64 patients with progressing ischemic stroke, glutamate concentrations measured at any time interval during the first 24 hours from onset were significantly higher than in the stable stroke and control groups., Conclusions: The presence of glutamate increase in the CSF cannot be documented for greater than 6 hours in stable ischemic stroke. The sustained elevation of glutamate observed in progressing stroke suggests that the window to prevent neurological deterioration may be wider.

Previous studies have shown that the levels of the microtubule-associated protein tau in the CSF of patients with Alzheimer's disease (AD) are elevated compared with age-matched controls. In spite of these findings, the nature of tau in CSF has not been well documented. In the present study, tau was immunoprecipitated from CSF of patients with AD or acute stroke, as well as normal elderly controls, followed by immunoblot analysis. In all cases, CSF tau consisted primarily of a band migrating at 26-28 kDa. In AD and stroke patients, several smaller tau fragments were also detected. No intact tau was detected in any of the CSF samples examined. Further immunoprecipitation studies showed that the majority of the tau fragments contained the amino terminus of the molecule. Treatment of CSF tau with alkaline phosphatase did not alter the electrophoretic properties of the fragments. These studies clearly demonstrate that CSF tau is truncated rather than intact.