Background: A low cerebrospinal fluid (CSF) white-blood cell count (WBC) has been identified as an independent risk factor for adverse outcome in adults with bacterial meningitis. Whereas a low CSF WBC indicates the presence of sepsis with early meningitis in patients with meningococcal infections, the relation between CSF WBC and outcome in patients with pneumococcal meningitis is not understood.
Methods: We examined the relation between CSF WBC, bacteraemia and sepsis in a prospective cohort study that included 352 episodes of pneumococcal meningitis, confirmed by CSF culture, occurring in patients aged >16 years.
Objectives: To describe clinical features of bacterial meningitis in older people.
Design: Cohort study.
Setting: Hospitals in the Netherlands.
We study interfacial phenomena in a colloidal dispersion of sterically stabilized gibbsite platelets, exhibiting coexisting isotropic and nematic phases separated by a sharp horizontal interface. The nematic phase wets a vertical glass wall and polarized light micrographs reveal homeotropic surface anchoring both at the free isotropic-nematic interface and at the wall. On the basis of complete wetting of the wall by the nematic phase, as found in our density functional calculations and computer simulations, we analyze the balance between Frank elasticity and surface anchoring near the contact line.
View Article and Find Full Text PDFPhilos Trans A Math Phys Eng Sci
October 2006
Gelation is a common effect in aqueous suspensions of charged colloidal clay platelets at concentrations as low as 1 wt%. However, in systems of charged gibbsite [Al(OH)3] platelets, gelation can be delayed to concentrations as high as 50 wt% depending on the ionic strength. We investigated the phase behaviour of this system approaching the state of gelation in the delicate region between attractive and repulsive states that originate from competition between Coulomb repulsion and van der Waals attraction.
View Article and Find Full Text PDFObjective: This follow-up study of the European Dexamethasone Study was designed to examine the potential harmful effect of adjunctive dexamethasone treatment on long-term neuropsychological outcome in adults with bacterial meningitis.
Methods: Neurological, audiological, and neuropsychological examinations were performed in adults who survived pneumococcal or meningococcal meningitis.
Results: Eighty-seven of 99 (88%) eligible patients were included in the follow-up study; 46 (53%) were treated with dexamethasone and 41 (47%) with placebo.
Nat Clin Pract Neurol
September 2006
Despite the availability of effective antibiotics, mortality and morbidity rates associated with bacterial meningitis are high. Studies in animals have shown that bacterial lysis, induced by treatment with antibiotics, leads to inflammation in the subarachnoid space, which might contribute to an unfavorable outcome. The management of adults with bacterial meningitis can be complex, and common complications include meningoencephalitis, systemic compromise, stroke and raised intracranial pressure.
View Article and Find Full Text PDFObjective: To evaluate whether soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) in CSF can serve as a biomarker for the presence of bacterial meningitis and outcome in patients with this disease.
Design: Retrospective study of diagnostic accuracy.
Setting And Patients: CSF was collected from 92 adults with community-acquired bacterial meningitis who participated in the prospective Dutch Meningitis Cohort Study; 8 patients with viral meningitis and 9 healthy control subjects.
Phys Rev E Stat Nonlin Soft Matter Phys
April 2006
The magnetic-field-induced orientational order in the isotropic phase of colloidal gibbsite [Al(OH)3] platelets is studied by means of optical birefringence and small-angle x-ray scattering (SAXS) techniques. The suspensions display field-induced ordering at moderate field strengths (a few Tesla), which increases with increasing particle concentration. The gibbsite particles align their normals perpendicular to the magnetic field and hence possess a negative anisotropy of their diamagnetic susceptibility Delta(chi).
View Article and Find Full Text PDFBacterial meningitis in adults is a severe disease with high fatality and morbidity rates. Experimental studies have shown that the inflammatory response in the subarachnoid space is associated with an unfavourable outcome. In these experiments, corticosteroids, and in particular dexamethasone, were able to reduce the inflammatory cascades in the subarachnoid space.
View Article and Find Full Text PDFBackground: Although the coexistence of bacterial meningitis and arthritis has been noted in several studies, it remains unclear how often both conditions occur simultaneously.
Methods: We evaluated the presence of arthritis in a prospective nationwide cohort of 696 episodes of community-acquired bacterial meningitis, confirmed by culture of cerebrospinal fluid, which occurred in patients aged >16 years. The diagnosis of arthritis was based upon the judgment of the treating physician.
Since the virtual eradication of meningitis due to Haemophilus influenzae type B by vaccination in the developed world, pneumococcal meningitis has become the leading cause of bacterial meningitis beyond the neonatal period. Clinical and experimental research has increased our knowledge about the pathophysiology and pathogenesis of the disease over the past decades. Despite the availability of effective antibiotics, supportive care facilities, and recent advances in adjunctive strategies-ie, adjunctive dexamethasone-mortality and morbidity rates associated with pneumococcal meningitis remain unacceptably high.
View Article and Find Full Text PDFEur J Clin Microbiol Infect Dis
February 2006
In experimental meningitis, adjunctive treatment with steroids reduces cerebrospinal fluid inflammation and thereby improves neurological outcome. On the basis of these findings, several clinical trials have assessed treatment with adjunctive steroids in bacterial meningitis, with conflicting results. Recently, the results of the European Dexamethasone Study showed a beneficial effect of adjunctive dexamethasone in adults with bacterial meningitis.
View Article and Find Full Text PDFBackground: Bacterial meningitis is a grave disease of high incidence, especially in less developed countries. Here, we describe its clinical presentation, spectrum of complications, prognostic factors, and outcome in adults with pneumococcal meningitis.
Methods: From October, 1998, to April, 2002, we assessed 352 episodes of community-acquired pneumococcal meningitis, confirmed by culture of cerebrospinal fluid (CSF), which occurred in patients older than 16 years.
Objective: To determine the effect of dexamethasone on prognostic factors in adults with bacterial meningitis.
Design And Setting: A post hoc multivariate analysis of the European Dexamethasone Study.
Patients And Participants: Dexamethasone-treated patients in the European Dexamethasone Study.
We study the competition between sedimentation, gelation, and liquid crystal formation in suspensions of colloidal gibbsite platelets of five different sizes at three ionic strengths. For large particles (with diameters of 350, 420, and 570 nm) sedimentation is initially the most important factor determining the macroscopic behavior. Only after the main part of the sample has sedimented in an amorphous phase, phase separation takes place.
View Article and Find Full Text PDFObjectives: To assess cognitive outcome and quality of life in patients with moderate disability after bacterial meningitis as compared to patients with good recovery.
Methods: Neuropsychological evaluation was performed in 40 adults after pneumococcal meningitis; 20 patients with moderate disability at discharge on the glasgow outcome scale (GOS score 4) and 20 with good recovery (GOS score 5).
Results: Patients with GOS score 4 had similar test results as compared to patients with GOS score 5 for the neuropsychological domains 'intelligence', 'memory' and 'attention and executive functioning'.
Association of a 16-fold excess of a monodisperse telechelic oligo(THF) (Mw = 1270 g/mol) containing two end groups that selectively bind to the 32 binding sites of a fifth generation dendritic host (Mw = 18,511 g/mol and radius R(h) = 2.4 nm) results in the formation of reversible and dynamic supramolecular complexes. The structure of these complexes in solution depends strongly on the concentration.
View Article and Find Full Text PDFWe report the observation of a new type of columnar liquid crystal phase, which is formed by thin hard colloidal disks in a dense suspension. High-resolution small-angle x-ray diffraction reveals a combination of long-range bond-orientational order and short-range translational order between the columns, the hallmark of the hexatic phase. Our results imply that geometric frustration related to the size polydispersity of the particles destroys long-range translational order and therefore promotes the formation of this novel phase.
View Article and Find Full Text PDFBacterial meningitis is a complex disorder in which neurologic injury is caused, in part, by the causative organism and, in part, by the host's own inflammatory response. In studies of experimental bacterial meningitis, adjuvant treatment with corticosteroids, specifically dexamethasone, has beneficial effects. On the basis of these experimental studies, several clinical trials were undertaken to determine the effects of adjunctive corticosteroids in patients with bacterial meningitis.
View Article and Find Full Text PDFWe report Small-Angle X-ray Scattering (SAXS) measurements of the columnar phase of hard colloidal gibbsite platelets. We have been able to create large oriented domains of the columnar phase both perpendicular and parallel to the sample wall, varying the volume fraction of platelets and adding non-adsorbing polymer to the dispersion. In conjunction with the increased resolution of the SAXS setup, this allowed a detailed analysis of the columnar phase, providing unambiguous evidence for the hexagonal nature of the phase.
View Article and Find Full Text PDFBackground: We conducted a nationwide study in the Netherlands to determine clinical features and prognostic factors in adults with community-acquired acute bacterial meningitis.
Methods: From October 1998 to April 2002, all Dutch patients with community-acquired acute bacterial meningitis, confirmed by cerebrospinal fluid cultures, were prospectively evaluated. All patients underwent a neurologic examination on admission and at discharge, and outcomes were classified as unfavorable (defined by a Glasgow Outcome Scale score of 1 to 4 points at discharge) or favorable (a score of 5).
The liquid crystal phase behavior of a suspension of charged gibbsite [Al(OH)3] platelets is investigated. By variation of the ionic strength, we are able to tune the effective thickness-to-diameter ratio of the platelets in suspension. This enables us to experimentally test the liquid crystal phase transition scenario that was first predicted a decade ago by computer simulations for hard platelets (Veerman, J.
View Article and Find Full Text PDFThe influence of gravity on a suspension of sterically stabilized colloidal gibbsite platelets is studied. An initially isotropic-nematic biphasic sample of such a suspension develops a columnar phase on the bottom on prolonged standing. This phenomenon is described using a simple osmotic compression model.
View Article and Find Full Text PDF