Comparison of C Reactive Protein and Procalcitonin Levels in Cerebrospinal Fluid and Serum to Differentiate Bacterial from Viral Meningitis

GOALS

It is unclear whether C reactive protein (CRP) and procalcitonin (PCT) levels in cerebrospinal fluid (CSF) improve the accuracy compared to their serum levels for the differential diagnosis of infectious meningitis. The aim of this study was to compare the accuracy of CRP and PCT levels in CSF and serum in order to differentiate between bacterial and viral meningitis.

PROCEDURES

CRP and PCT levels were measured in CSF and serum from patients with bacterial or viral meningitis. The diagnostic accuracy was determined using receiver operating characteristic curves (ROC), calculating the area under the ROC curve (AUC).

RESULTS

Thirty patients were included in this study, 18 of whom had bacterial meningitis and 12 viral meningitis. The AUCs to differentiate bacterial from viral meningitis using serum CRP, CSF CRP, serum PCT and CSF PCT were 0.926; 0.898; 0.963; and 0.694 respectively. Serum CRP and PCT exhibited 100% and 88.9% sensitivity, 83.3% and 100% specificity with a cut-off =14.0 mg/L and 0.18 μg/L respectively.

CONCLUSIONS

Levels of CRP and PCT in CSF did not present greater accuracy in differentiating bacterial from viral meningitis compared to serum levels. Serum CRP and PCT showed a high diagnostic accuracy, therefore its quantification is recommended in all patients with suspected infectious meningitis.

Blood-Brain Barrier and Intrathecal Immune Response in patients with neuroinfections

Cerebrospinal fluid/serum albumin ratio is one of the most informative parameters for blood-brain barrier (BBB) integrity in cases of central nervous system (CNS) infectious diseases. Normally, CNS albumin concentration is a function of diffusion processes along with CSF drainage and resorption. In pathological processes CSF albumin levels are dependent only on the rate of CSF drainage resulting in non-linear reciprocal changes of albumin quotient (Qalb). IgG, IgA and IgM concentrations both in CSF and serum can be compared to Qalb, thus determining the intrathecal immune response. The aim of the study was to detect BBB permeability impairment and the intrathecal immune response in patients with CNS infections with various etiologies. CSF/serum ratios were calculated and related to IgG IgA and IgM concentrations in CSF and blood serum. The results were integrated and presented by Reibergrams. The results demonstrated typical patterns which prove albumin to be the main modulator of protein dynamics and at the same time explicates the complex pathophysiological mechanisms involved in BBB disruption and intrathecal immune response in CNS infections. The diagnostic model presented in our study seeks to explain the observations of meningitis and meningoencephalitis pathophysiology and points out the mandatory cooperation between clinicians and laboratory for accurate diagnosis and proper treatment.

Diagnostic value of lactate, procalcitonin, ferritin, serum-C-reactive protein, and other biomarkers in bacterial and viral meningitis: A cross-sectional study

There are many difficulties distinguishing bacterial from viral meningitis that could be reasonably solved using biomarkers. The aim of this study was to evaluate lactate, procalcitonin (PCT), ferritin, serum-CRP (C-reactive protein), and other known biomarkers in differentiating bacterial meningitis from viral meningitis in children.All children aged 28 days to 14 years with suspected meningitis who were admitted to Mofid Children's Hospital, Tehran, between October 2012 and November 2013, were enrolled in this prospective cross-sectional study. Children were divided into 2 groups of bacterial and viral meningitis, based on the results of cerebrospinal fluid (CSF) culture, polymerase chain reaction, and cytochemical profile. Diagnostic values of CSF parameters (ferritin, PCT, absolute neutrophil count [ANC], white blood cell count, and lactate) and serum parameters (PCT, ferritin, CRP, and erythrocyte sedimentation rate [ESR]) were evaluated.Among 50 patients with meningitis, 12 were diagnosed with bacterial meningitis. Concentrations of all markers were significantly different between bacterial and viral meningitis, except for serum (P = .389) and CSF (P = .136) PCT. The best rates of area under the receiver operating characteristic (ROC) curve (AUC) were achieved by lactate (AUC = 0.923) and serum-CRP (AUC = 0.889). The best negative predictive values (NPV) for bacterial meningitis were attained by ANC (100%) and lactate (97.1%).The results of our study suggest that ferritin and PCT are not strong predictive biomarkers. A combination of low CSF lactate, ANC, ESR, and serum-CRP could reasonably rule out the bacterial meningitis.

With a little help from a computer: discriminating between bacterial and viral meningitis based on dominance-based rough set approach analysis

Differential Diagnosis of bacterial and viral meningitis remains an important clinical problem. A number of methods to assist in the diagnoses of meningitis have been developed, but none of them have been found to have high specificity with 100% sensitivity.We conducted a retrospective analysis of the medical records of 148 children hospitalized in St. Joseph Children's Hospital in Poznań. In this study, we applied for the first time the original methodology of dominance-based rough set approach (DRSA) to diagnostic patterns of meningitis data and represented them by decision rules useful in discriminating between bacterial and viral meningitis. The induction algorithm is called VC-DomLEM; it has been implemented as software package called jMAF (http://www.cs.put.poznan.pl/jblaszczynski/Site/jRS.html), based on java Rough Set (jRS) library.In the studied group, there were 148 patients (78 boys and 70 girls), and the mean age was 85 months. We analyzed 14 attributes, of which only 4 were used to generate the 6 rules, with C-reactive protein (CRP) being the most valuable.Factors associated with bacterial meningitis were: CRP level ≥86 mg/L, number of leukocytes in cerebrospinal fluid (CSF) ≥4481 μL, symptoms duration no longer than 2 days, or age less than 1 month. Factors associated with viral meningitis were CRP level not higher than 19 mg/L, or CRP level not higher than 84 mg/L in a patient older than 11 months with no more than 1100 μL leukocytes in CSF.We established the minimum set of attributes significant for classification of patients with meningitis. This is new set of rules, which, although intuitively anticipated by some clinicians, has not been formally demonstrated until now.

Age-specific application of neutrophil-to-lymphocyte ratio in meningitis: a nationwide study

Cerebrospinal fluid (CSF) neutrophil counts and neutrophil-to-lymphocyte ratio (NLR) are useful in distinguishing bacterial and viral meningitis. Given that meningitis is clinically heterogeneous with regard to age, here we investigated the validity of the CSF NLR and neutrophil assay according to age group. Data from the nationwide referral of >4,000 meningitis cases to the Hellenic Meningitis Reference Laboratory between 2006 and 2013 were examined. CSF NLR and neutrophil counts were stratified according to age, and assay performance was determined using previous cut-off values of 2 and 287 cells/μl for CSF NLR and neutrophils respectively. The distribution of bacterial versus viral meningitis was heterogenous across age groups, with a low proportion of bacterial meningitis in patients aged 5-14. CSF neutrophil count and NLR were significantly more discriminatory for bacterial meningitis in patients aged over 14 years than those aged 0-14. The odds ratio (OR), sensitivity, specificity and positive predictive value (PPV) were significantly higher in older patients for both biomarkers. When combined, the false-positive and false-negative detection of bacterial meningitis was 3.9 and 8.5% respectively, and the OR of 262.2 was 2.5-fold greater than expected from a multiplicative effect alone in patients aged >14 years. Care is required when applying diagnostic tests for meningitis in different age groups because of patient heterogeneity. This is the first description of the age distribution of meningitis cases in Greece, and knowledge of the age-related distribution of neutrophils and NLR in meningitis cases could help towards developing age-specific meningitis diagnostic assays.

Usefulness of blood and cerebrospinal fluid laboratory testing to predict bacterial meningitis in the emergency department

INTRODUCTION

The classic clinical presentation of bacterial meningitis (BM) is observed in less than half of the cases in adults, and symptoms are less specific in children, the elderly or immunocompromised, and other chronic patients. The usual signs and symptoms do not provide optimal sensitivity and specificity for distinguishing possible BM from viral meningitis (VM), which may lead to a delay in the appropriate antimicrobial therapy. Society therefore stands to benefit from the development of effective, objective, and rapid tools able to predict and identify patients with BM. These tools include laboratory tests for blood and cerebrospinal fluid (CSF). The aim of this review is to summarise recently published scientific evidence in order to clarify existing controversies and compare the usefulness and diagnostic ability of the different parameters used to predict BM.

DEVELOPMENT

Systematic search of the main bibliographic databases and platforms to identify articles published between January 2000 and January 2016. We selected 59 articles that meet the objectives of this review.

CONCLUSIONS

CSF lactate, proportion of polymorphonuclear leukocytes, and CSF glucose, as well as serum procalcitonin (PCT), are the independent factors most predictive of bacterial aetiology. The model that combines serum PCT and CSF lactate achieves the highest predictive power for BM, with a sensitivity and specificity exceeding 99%. We should consider BM when CSF lactate >33 md/dL and/or PCT>0.25ng/mL.

EDA-containing fibronectin levels in the cerebrospinal fluid of children with meningitis

Fibronectin containing an alternatively spliced extra domain A (EDA-FN) participates in diverse biological cell functions, being also directly or indirectly engaged during an inflammatory response to brain injury and/or neuron regeneration. We analyzed FN and EDA-FN isoform levels by ELISA in 85 cerebrospinal fluid samples and 67 plasma samples obtained from children suffering from bacterial or viral meningitis and non-meningitis peripheral inflammation. We have found that the cerebrospinal level of EDA-FN was significantly lower in the bacterial meningitis group than in the viral- and non-meningitis groups. In the patients' plasma, EDA-FN was almost undetectable. The determination of fibronectin containing the EDA segment might be considered as an additional diagnostic marker of bacterial meningitis in children.

Diagnostic value of soluble CD163 serum levels in patients suspected of meningitis: Comparison with CRP and procalcitonin

The aim of the study was to evaluate and compare the diagnostic value of sCD163 serum levels with CRP and PCT in meningitis and bacterial infection. An observational cohort study was conducted between February 2001 and February 2005. The study population comprised 55 patients suspected of meningitis on admission to a 27-bed infectious disease department at a Danish university hospital. Biomarker serum levels on admission were measured. Sensitivity and specificity were evaluated at pre-specified cut-off values and overall diagnostic accuracies were compared using receiver-operating characteristic AUCs (areas under curves). Patients were classified by 2 sets of diagnostic criteria into: A) purulent meningitis, serous meningitis or non-meningitis, and B) systemic bacterial infection, local bacterial infection or non-bacterial disease. An elevated serum level of sCD163 was the most specific marker for distinguishing bacterial infection from non-bacterial disease (specificity 0.91; sensitivity 0.47). However, the overall diagnostic accuracy of CRP (AUC =0.91) and PCT (AUC =0.87) were superior (p<0.02 and p<0.06) compared to that of sCD163 (AUC =0.72). For the diagnosis of systemic bacterial infection, the AUC of sCD163 (0.83) did not differ significantly from those of CRP or PCT. All markers had AUCs <0.75 for differentiating between purulent meningitis and other conditions. In conclusion, CRP and PCT had high diagnostic value and were superior as markers of bacterial infection compared to sCD163. However, sCD163 may be helpful in rapid identification of patients with systemic bacterial infection. If used as an adjunct to lumbar puncture, PCT and CRP had very high diagnostic accuracy for distinguishing between bacterial and viral infection in patients with spinal fluid pleocytosis. However, none of the markers was useful as an independent tool for the clinical diagnosis of patients with purulent meningitis.

[Laboratory testing of specimens from patients with viral encephalitis from some regions of China]

OBJECTIVE

To understand the viral etiology of viral encephalitis in China by detecting IgM antibody and viral RNA in the clinical samples of patients from some provinces of China by enzyme-linked immunosorbent assay and polymerase chain reaction.

METHOD

Serum and cerebrospinal fluid samples of 771 patients with viral encephalitis or meningitis were collected from six provinces of China and were stored at -20 degrees C or -70 degrees C. Enzyme-linked immunosorbent assays were used for detection of IgM antibody to Japanese encephalitis virus, coxsackievirus, echovirus, herpes simplex virus, measles virus, varicella-zoster virus, mumps virus, cytomegalovirus and Epstein-Barr virus. Polymerase chain reaction was applied for the detection of viral RNA of enteroviruses and seadornavirus.

RESULTS

IgM antibody was detected in 567 of 771 (73.5%) cases. The most common pathogen was Japanese encephalitis virus (47.0%, 362/771), followed by mumps virus (10.6%, 82/771), enteroviruses (8.8%, 68/771), herpes simplex virus (5.7%, 44/771), measles virus (0.4%, 3/771), varicella-zoster virus (0.4%, 3/771), Epstein-Barr virus (0.4%, 3/771), and cytomegalovirus (0.3%, 2/771). Enterovirus was positive in 8 cases, seadornavirus was negative in all the cases by PCR.

CONCLUSION

According to the study, Japanese encephalitis was the most important encephalitis in China. Mumps virus was another important pathogen. Enteroviruses and herpes simplex virus were also important pathogens.

[Cilliary neurotrophic factor in tick-borne encephalitis]

THE PURPOSE OF THIS STUDY

To evaluate concentrations of cilliary neutrophic factor (CNTF) in serum and cerebrospinal fluid of patients with tick-borne encephalitis (TBE) and bacterial meningitis.

MATERIAL AND METHODS

49 patients (14 females and 35 males), aged 19 to 62 were examined. Patients were divided into three groups: group I--23 patients (47%) with diagnosed TBE, group II--16 patients (33%) with bacterial meningitis and 10 (20%) healthy individuals as control group. The examination was performed twice before and after 4-weeks treatment. In achieved results CNTF concentration in serum from group I and II in both examinations was significantly higher compared to control group.

RESULTS

Patients with TBE showed higher serum CNTF concentration compared to group with bacterial meningitis in both examinations as well. In examination 1 cerebrospinal fluid CNTF concentration of both groups was significantly higher in comparison to control group. Examined cytokine CSF concentration was higher in group with bacterial meningitis. After treatment CNTF concentration decreased significantly in group I and II. In group I CNTF concentration was comparable to control group.

CONCLUSION

Concentration of CNTF in csf could be used as a marker of the inflammatory process in the central nervous system.

[Expression of inflammatory mediators in meningitis]

BACKGROUND

Infectious diseases cause a systemic inflammatory reaction. In some cases of meningitis it is difficult to determine whether the disease is of bacterial, viral or non-infectious origin. In order to distinguish between bacterial and viral diseases the levels of various inflammatory markers are used to determine the severity of the disease and the clinical prognosis.

OBJECTIVE

The purpose of this study was to determine whether the levels of different markers can be used to distinguish between bacterial or viral meningitis or non-infectious neurological disease.

METHODS

Patients with bacterial meningitis (n= 8), viral meningitis (n= 17), non-infectious neurological diseases (n = 17) and healthy subjects (n = 15) were studied. The levels of soluble CD14 (sCD 14), interleukin-6 (IL-6), interleukin-1beta (IL-1beta) and soluble adhesion molecule-1 (sICAM-1) were determined in the blood of all participants and in spinal fluid only in patients who had clinical indication to perform lumbar puncture.

RESULTS

All the patients showed significant differences in the levels of blood and CSF markers measured compared to healthy subjects. In the blood, although some differences were significant, there was overlapping between all values of the measured markers in patient blood samples excluding IL-6, for which levels were significantly different between the bacterial and viral meningitis. Interestingly, the levels of all markers showed significant differences among all groups of patients.

CONCLUSIONS

Among the blood markers examined, IL-6 can be used to distinguish between bacterial and viral diseases. However, the levels of cytokines examined in CSF, can serve to distinguish between bacterial and viral meningitis and non-infectious diseases.

[Concentration of interleukin 6 and 10 in tick-borne and purulend encephalomeningitis]

The aim of the study was to evaluate concentrations of interleukin 6 (IL-6) and interleukin (IL-10) in serum and cerebrospinal fluid (csf) of patients with tick-borne encephalitis (tbe) and purulent meningitis before and after 4 weeks of treatment.

MATERIAL AND METHODS

Group I consisted of 23 patients with tbe and group II - 16 patients with bacterial meningitis. Group III (control) consisted of 10 healthy men.

RESULTS AND CONCLUSIONS

In patients with tbe and purulent meningitis concentrations of IL-6 and IL-10 in serum and csf were initially increased and tended to remain increased after 4 weeks of treatment. It suggests significant role of IL-6 and IL-10 in inflammatory process within cns. Higher concentrations of IL-6 than IL-10 in csf than in serum suggests their local synthesis within cns and tendency to the limitation of the inflammatory response to the intratecal compartment. Concentrations of both IL-6 and IL-10 in csf and serum remained sgnificantly higher in patints with purulent meningits than in tbe, both before and after treatment. This observation may be helpful in diagnosing the ethiology of meningitis and meningoencephalitis and monitoring the course of the disease.

[Serum procalcitonin levels in children with bacterial or viral meningitis]

OBJECTIVE

To investigate the ability of serum procalcitonin (PCT) to differentiate between bacterial and viral meningitis.

METHODS

The serum PCT levels were measured in 41 children with acute bacterial (n=18) or viral (n=23) meningitis by immunoluminometric assay. Meanwhile serum CRP levels and erythrocyte sedimentation rate (ESR) were measured.

RESULTS

The children with acute bacterial meningitis had higher levels of PCT (51.73 +/- 30.75 microg/L) and CRP(182.36 +/- 54.5 mg/L) and ESR (50.44 +/- 8.95 mm/h) than those with viral meningitis (0.84 +/- 0.99 microg/L, 8.90 +/- 10.66 mg/L and 16.75 +/- 13.23 mm/h respectively, P < 0.01). Both PCT and CRP had high predictive value for bacterial meningitis based on the area under curve of the receiver operating characteristics curves, 0.984 for PCT (95% confidence interval 0.953-1.013) and 0.983 for CRP (95% confidence interval 0.954-1.012) (P > 0.05). All of the children with bacterial meningitis had serum PCT levels above 0.5 microg/L, but only 2 patients with viral meningitis exceeded this value.

CONCLUSIONS

The measurement of serum PCT levels may be of value in the differential diagnosis of meningitis due to either bacterial or viruses.

Serum procalcitonin and cerebrospinal fluid cytokines level in children with meningitis

AIMS: To determine the level of serum procalcitonin and cerebrospinal fluid cytokines in children with bacterial or viral meningitis and to document the use of these parameters in differential diagnosis. RESULTS: Before the start of antibiotic treatment, serum procalcitonin and tumor necrosis factor alpha levels were found to be higher in acute bacterial meningitis compared with viral meningitis and with the control group. Similarly, cerebrospinal fluid interleukin-6 levels were found to be significantly higher in children with acute bacterial meningitis compared with viral meningitis. However, no significant difference was determined between groups in respect to the cerebrospinal fluid interleukin-8 level. CONCLUSION: Serum procalcitonin and cerebrospinal fluid tumor necrosis factor alpha levels can be used in the early diagnosis of bacterial meningitis. Similarly, they may be useful adjuncts in differential diagnosis of bacterial and viral meningitis.

Diagnosis of Enteroviral Meningitis by Use of Polymerase Chain Reaction of Cerebrospinal Fluid, Stool, and Serum Specimens

BACKGROUND

Because enteroviruses can be detected in various clinical samples during enteroviral meningitis, we analyzed the combined diagnostic utility of polymerase chain reaction (PCR) of cerebrospinal fluid (CSF), feces, and serum for detection of enterovirus in specimens obtained from adults with aseptic meningitis or encephalitis.

METHODS

PCR results were analyzed for 34 adults for whom enteroviral meningitis was diagnosed on the basis of virus isolation and antibody detection in our hospital during 1999-2003. PCR results were also analyzed for 77 adults with meningitis or encephalitis of another defined cause for whom this assay was used for diagnostic evaluation during that period.

RESULTS

Twenty-six (76%) of 34 CSF samples and 24 (96%) of 25 fecal samples collected from patients with enteroviral meningitis had positive PCR results. The diagnostic yield of the test was lower for CSF specimens obtained >2 days after clinical onset, compared with CSF collected < or =2 days after onset. Instead, PCR of feces was highly useful also later, because 12 of the 13 fecal specimens obtained 5-16 days after clinical onset had positive test results. None of 75 CSF samples and 2 of 48 fecal samples obtained from patients with nonenteroviral infection had positive PCR results. All serum samples were PCR negative.

CONCLUSIONS

PCR of fecal specimens obtained throughout the course of enteroviral meningitis had the highest clinical sensitivity for detecting enterovirus. It is recommended that, in addition to performance of CSF PCR, fecal samples collected from patients with suspected enteroviral meningitis should be tested by PCR, especially when the duration of symptoms is >2 days.

[Procalcitonin (PCT) concentration in cerebrospinal fluid and plasma of patients with purulent and lymphocytic meningoencephalitis--own observations]

The aim of the study was assessment of usefulness of cerebrospinal fluid (CSF) and plasma procalcitonin concentration estimation in differential diagnosis of neuroinfections in adults. Examinations were carried out in 17 subjects with purulent, bacterial meningoencephalitis and in 16 patients with lymphocytic meningitis. In all individuals CSF and plasma PCT concentrations were assessed on the 1st day of hospitalization. In patients with purulent, bacterial meningoencephalitis mean CSF concentration was 0,63 ng/mL, mean plasma PCT concentration--9,97 ng/mL. Mean CSF PCT concentration in patients with lymphocytic meningitis was 0,23 ng/mL and mean plasma PCT concentration--0,27 ng/mL. Differences of mean PCT concentrations between both groups of patients were statistically significant: CSF--p<0,05 and plasma--p<0,01. Obtained results indicate usefulness of plasma PCT concentration estimation in differential diagnosis of neuroinfections in adults. Cerebrospinal fluid PCT concentration seems to be of lesser importance in differential diagnosis of neuroinfections, but value of this parameter often correlates with the severity of the clinical state of the patients and may be taken into consideration in prognosis of the course and outcome of the bacterial meningoencephalitis.

Production d’interféron alpha dans le sérum des très jeunes nourrissons lors d’infections virales

IFN-alpha detection is useful in some clinical circumstances, but its use has never been validated in young infants with viral infections.

OBJECTIVE

The authors wanted to determine it there was any difference in the assessment of IFN-alpha production between infants under or over six months of age.

PATIENTS AND METHOD

A series of 233 children with identified common viral infections who had been assessed for IFN-alpha production was retrospectively analyzed. The viral infections were enteroviral meningitis (n =103), respiratory syncytial virus infections (n =60), and rotavirus gastroenteritis (n =70). Data collected from the group of infants under six months of age (n =105) was compared to that of the older children (n =128). Qualitative and quantitative values of interferon-alpha were determined for each group.

RESULTS

Interferon-alpha was detected in very young infants (81.9% of cases) as often as in the older age group (80.3% of cases), for any of the three viral infections (P =0.3-0.63). The mean level of interferon-alpha production detected was not lower in the youngest group, and even higher in the group under six months of age with enteroviral meningitis.

CONCLUSION

Interferon-alpha detection in very young infants is efficient and may be useful to differentiate between viral and bacterial infection particularly when the etiological diagnosis appears uncertain.

Elevated serum C-reactive protein in mumps orchitis

A case of mumps orchitis with a high concentration of C-reactive protein (CRP) prompted us to evaluate the inflammatory response in mumps complications. We compared the CRP titers in mumps patients with orchitis and meningitis. The serum CRP titers were significantly higher in the patients with orchitis than in those with meningitis.

Méningites à examen bactériologique direct négatif

OBJECTIVE

Elaboration of a decision-making tree for differential diagnosis of bacterial and viral meningitis, when initial Gram's staining is negative. Method One-Year prospective study in an adult emergency department. Comparison with the immediately-preceding period.

RESULTS

56 patients were included. Only 4 bacterial meningitis, but none misdiagnosed. 86% sensitivity and 83% specificity for viral meningitis (n=40). Rate of patients hospitalised more than 24 hours decreasing from 62.5 to 41% (p=0.05). Antibiotic chemotherapy decreasing from 55 to 16% (p<0.001).

CONCLUSION

This decision-making tree safely allows emergency differentiation between bacterial and viral meningitis, when initial Gram's staining is negative. It consequently leads to decreased rates of useless hospitalisations and antibiotic treatments. We believe that this method can be helpful during outbreaks of viral meningitis.

[Does the assay of acute phase protein concentrations in cerebrospinal fluid and/or in serum in patient with viral meningitis have a diagnostic value? Part II. Lymphocytic meningitis caused by echo 30 virus]

The aim of the study was to evaluate dynamics of selected acute phase proteins in serum and cerebrospinal fluid (CSF) in children with viral meningitis and to assess diagnostic power of protein determination for detection and treatment monitoring. 51 children with viral meningitis caused by ECHO 30 virus were included in the study group. Concentration of C-reactive protein (CRP), alpha 1-antitrypsin (AAT), alpha1-acid glycoprotein (AAG), alpha2-haptoglobin (HPT) and C3 complement fragment were determined in serum and CSF at entry and at day 14 after admittance to hospital. Control group for serum determination consisted in 30 healthy children (Group K1) and control group for CSF determination consisted in 19 hospitalized children in whom the diagnosis of meningitis was not confirmed (group K2). The greatest rise of acute phase proteins concentration was observed in children in case of HPT, AAG and C3 complement when determined in serum. Meningitis in children that was caused by ECHO 30 virus produces slight acute phase reaction that is more evident in serum than in CSF. It is confirmed by remarkable increase of AAG, HPT, C3 complement in serum and HPT in CSF either at entry or at the day 14. The determination of AAG, HPT and C3 complement in serum have diagnostic power that is strong enough to meningitis diagnostics and monitoring of treatment.

[Does the estimation of acute phase protein concentrations in cerebrospinal fluid and/or in serum in patients with viral meningitis carry diagnostic importance? Part I. Lymphocytic meningitis caused by epidemic parotitis]

OBJECTIVE

We examined whether an acute phase reaction could occur in children with lymphocytic meningitis of homogeneous etiology (parotitis epidemic from the Paramyxoviridae family), a sign of which would be an increase in concentrations of acute phase proteins (APP's) in cerebrospinal fluid (CSF) and/or in blood serum. We also tested the usefulness of the determination of selected APP's concentrations in CSF and serum in diagnosis and monitoring of the course of the disease, provided that an increase in concentrations of selected APP's were discernible.

METHODS

Cases were 78 children with lymphocytic meningitis as a complication of parotitis epidemic. Controls were 30 healthy children (control group K1) and 19 children hospitalized with suspected meningitis (control group K2). The following APP's presence in CSF and serum were tested: C-reactive protein (CRP), alpha-2-haptoglobin (HPT), alpha-1-antitripsin (AAT) and alpha-1-acid glycoprotein (AAG), alpha-2-ceruloplasmin (CER) and alpha-2-macroglobulin (AMG). The results were compared and analyzed.

RESULTS

The results of the research show a significant increase in all APP's determined, except for CRP and AAG, in children with parotidal meningitis.

CONCLUSIONS

Determination of CRP concentration either in CSF or in serum is not useful in diagnosis of parotidal meningitis and in differentiation of lymphocytic and bacterial forms of the disease.

CSF and serum levels of soluble fractalkine (CX3CL1) in inflammatory diseases of the nervous system

The new CX(3)C-chemokine fractalkine (CX(3)CL1) was measured by Western blot in the cerebrospinal fluid (CSF) and serum of patients with inflammatory diseases of the peripheral and central nervous system (Bell's palsy, BP; Guillain-Barré Syndrome, GBS; multiple sclerosis, MS; viral meningitis, VM; bacterial meningitis, BM) and patients with noninflammatory neurological diseases (controls). In controls, fractalkine was detectable at low concentrations in the CSF and, at much higher levels, in serum. In all inflammatory neurological diseases under study, CSF fractalkine levels were significantly (p<0.01) increased vs. controls (BM>>GBS>VM>MS>BP>controls). In serum, fractalkine levels were significantly increased only in MS patients. The fractalkine CSF/serum ratios (a measure of the chemotactic gradient) were significantly elevated in BM, VM and GBS; furthermore, they tended to be increased in BP and to be decreased in MS. The elevated fractalkine CSF/serum ratios in diseases without CSF pleocytosis (GBS, BP) and a lack of correlation between fractalkine levels and CSF leukocyte counts suggested that soluble fractalkine is not a major chemokine in the CSF. There was no evidence of significant intrathecal production of fractalkine as the mean fractalkine indices (fractalkine CSF/serum ratio:albumin CSF/serum ratio) were <1 in all inflammatory diseases and not significantly elevated vs. controls.

[Acute meningitidis, acute phase proteins and procalcitonin]

The prognosis of bacterial meningitis is critically dependent on a rapid causal diagnosis and implementation of an accurate treatment. However, clinical and biological parameters available within the few hours that follow the patient's admission are not reliable enough, except when bacteria are to be found in cerebrospinal fluid under the microscope. Therefore, the initial treatment of acute meningitis is still most of time presumptive so that the definitive diagnosis, however difficult, is often established when the therapeutic management has already been initiated. The use of biological markers, especially lymphokines and acute-phase proteins, has been proposed to facilitate the accuracy of the initial diagnosis. Today, C-reactive protein (CRP) is the most widely used inflammatory marker in emergency departments with aim to discriminate bacterial from viral infections. In 1998, Gerdes et al. published a meta-analysis from 35 studies questioning the usefulness of CRP in discriminating bacterial meningitis from viral meningitis. They outlined that the majority of authors proposed to use this inflammation marker as an additional tool for discriminating bacterial meningitis from viral meningitis, without having evaluated its independent contribution relative to other parameters such as white blood cell count, cerebrospinal fluid (CSF) white cell count, protein or glucose. Procalcitonin (PCT) is an acute-phase protein with faster kinetics than CRP, its concentration in serum rising within the few hours that follow the inception of a bacterial infection. Two French studies published in 1997 and 1998 have shown that, using a cut-off range of 0.5 through 2 ng/mL, the sensitivity and specificity of PCT were 100% in discriminating bacterial meningitis from viral meningitis. Some of the seven studies published since seemed to demonstrate the usefulness of PCT in diagnosing meningitis. Finally, PCT was used effectively to shorten unnecessary antibiotic treatment for children seen in an hospital in Paris (France) during summer 2000.

Acute meningitis due to Toscana virus infection among patients from both the Spanish Mediterranean region and the region of Madrid

Toscana virus (TOSV) is a member of the genus Phlebovirus that is transmitted to humans by two different species of sand fly and causes acute aseptic meningitis (AAM) and meningoencephalitis in Central Italy. Fifteen cases of AAM due to TOSV have been found at the Spanish province of Granada, but no data regarding the presence of TOSV-related disease in other regions of Spain have been still reported. A collection of 88 serum and 53 cerebrospinal fluid (CSF) samples taken from 81 selected patients with AAM of unknown aetiology, residing at Madrid or at the southern Mediterranean coast of Spain, was retrospectively studied for presence of TOSV-specific antibodies from both IgG and IgM classes. Anti-TOSV IgG was also investigated in 457 serum samples from healthy individuals, aged 2-60 years, residing at the south of the Region of Madrid. Specific IgM in serum and/or intrathecally produced anti-TOSV IgG were detected in seven patients, three residents from the Mediterranean region and the remainder four from the Region of Madrid. The overall prevalence of anti-TOSV among the healthy population studied was 5%. These results confirm the role of TOSV as an agent causing AAM in the Spanish Mediterranean coast, extend these findings to the central region of the country and suggest that TOSV might be producing infection and neurological disease in every area of Spain harbouring significant populations of the viral vectors.

Low sensitivity of serum procalcitonin in bacterial meningitis in adults

Several studies have suggested high predictive values of serum procalcitonin (PCT) for the discrimination of bacterial and viral meningitis in children and adults. Here, we report PCT serum concentrations in 12 adults suffering from bacterial meningitis. PCT on admission was normal ( < or = 500 pg/ml) in 3 and between 500 and 1,000 pg/ml in 2 patients without evidence of concurrent bacterial infections. Conversely, in 5 patients with PCT concentrations between 2,268 and 38,246 pg/ml other infections were present. PCT concentrations were higher with typical meningitis agents (pneumococci and meningococci 12,679 +/- 13,092 pg/ml vs. other bacteria 4048 +/- 9187 pg/ml, p = 0.041) whilst in nosocomial bacterial meningitis after neurosurgery (n = 3) serum PCT remained normal. We believe that PCT is of limited diagnostic value in adults suffering from bacterial meningitis, especially in cases due to unusual agents or of nosocomial origin. Elevated PCT in bacterial meningitis may indicate the presence of bacterial inflammation outside the central nervous system.

Detection of Coxsackievirus B 4 antibodies in cases of suspected encephalopathy by microneutralization test

A retrospective study of serum and cerebrospinal fluid (CSF) samples collected from suspected viral encephalitis and encephalopathy cases was carried-out and it included 100 CSF and 89 serum samples from Goa, collected during 1990-1994. These samples which were negative for antibodies to Japanese encephalitis (JE), West Nile (WN), Dengue-2 (DN-2) and herpes viruses, were tested for Coxsackievirus B 4 specific antibodies by 'in vitro' microneutralization technique along with 80 negative control serum samples. Out of 189 specimens (100 CSF and 89 serum), 23 CSF and 41 serum samples were positive for Coxsackievirus B 4 neutralizing antibodies. Antibody profile seemed to be IgG as revealed by mercaptoethanol treatment. The presence of neutralizing antibodies to coxsackievirus B 4 with titres as high as 1:512 in 8 CSF and 19 serum samples seemed to be suggestive of viral meningitis due to Cox B-4 viruses.

Follistatin (FS) in human cerebrospinal fluid and regulation of FS expression in a mouse model of meningitis

OBJECTIVE

Follistatin (FS) is the specific binding protein of activin and expression of both factors is regulated by inflammatory agents. Therefore, FS concentrations were determined in cerebrospinal fluid (CSF) of patients with bacterial and viral meningitis or multiple sclerosis (MS), as well as in the CSF of patients without meningial inflammation or autoimmune diseases. Furthermore, a mouse pneumococcal meningitis model was used to localise the cellular sources of FS in brains of normal and meningitic mice.

METHODS

FS concentrations in CSF were determined by ELISA; FS in mice was localised by in situ hybridisation and immunohistochemistry.

RESULTS

FS concentrations were > or =0.4 microg/l in 22 of 66 CSF samples of meningitis patients versus 2 of 27 CSF samples from patients with multiple sclerosis (P<0.05) and 2 of 41 CSF specimen from patients without neuroinflammatory diseases (P<0.01). In the CSF of patients with meningitis, the concentration of FS was correlated with total protein (P<0.005) and lactate concentrations (P<0.05), but not with leukocyte counts, interval between onset of disease and CSF analysis, or clinical outcome. The CSF-to-serum ratios of FS and albumin also correlated significantly (P<0.0005). In some patients with meningitis the CSF-to-serum ratios suggested that the elevated FS in CSF did not originate from serum alone. FS was localised in mice brains to neurones of the hippocampus, dentate gyrus, neocortex, and to the choroid plexus. Analyses of brains and other organs from uninfected and infected animals sacrificed 6-36 h after infection did not reveal any obvious differences in the distribution and intensity of FS mRNA and protein expression.

CONCLUSIONS

The concentration of FS in humans is elevated during meningitis. In some patients the increase is caused by a release of FS from brain into CSF. Data from the mouse meningitis model suggest that increased CSF concentrations of FS in meningitis appear not to be accompanied by an elevated number of cells containing FS mRNA or protein in the brain.

Plasma levels of 24S-hydroxycholesterol in patients with neurological diseases

The brain is the exclusive or almost exclusive site of formation of 24S-hydroxycholesterol and we have shown that the circulating level of 24S-hydroxycholesterol is dependent upon the relation between cerebral production and hepatic clearance. In the present work we determined plasma levels of 24S-hydroxycholesterol in patients with various neurological diseases. Eleven subjects with brain death occurring 6-10 h before collection of the plasma samples had markedly reduced circulating levels of 24S-hydroxycholesterol (-43%, P<0.001). Patients with advanced Alzheimer's disease and cerebral inflammatory diseases had slightly lower levels of 24S-hydroxycholesterol in plasma when compared to matched controls. Patients with acute ischemic stroke, multiple sclerosis and primary brain tumors had levels not significantly different from those of controls. The conditions leading to reduced plasma levels of 24S-hydroxycholesterol had no significant effect on plasma levels of another side-chain oxidized oxysterol, 27-hydroxycholesterol. Except for conditions characterized by very marked destruction of the central nervous system, different severe neurological diseases seem to have relatively small effects on the flux of 24S-hydroxycholesterol from the brain.

[Rapid diagnosis of the type of meningitis (bacterial or viral) by the assay of serum procalcitonin]

OBJECTIVE

It has been shown that serum procalcitonin (PCT) can be used to differentiate bacterial from viral meningitis in children in all cases. The aim of this study was to demonstrate the interest of PCT in the management of suspected meningitis in adults.

PATIENTS AND METHODS

We conducted a prospective study including 179 consecutive patients admitted to the emergency department for suspected meningitis. All samples were taken at patient admission. The discriminant potential between bacterial and viral meningitis was studied for cerebrospinal fluid parameters (cytology, protein, glucose, lactate) and serum parameters (C reactive protein, PCT).

RESULTS

Thirty-two patients had bacterial meningitis, 90 had viral meningitis and meningitis was ruled out in 57. Among all studied parameters, the most discriminant for distinguishing between bacterial and viral meningitis in 100% of the cases proved to be serum procalcitonin with a threshold value of 0.93 ng/ml.

CONCLUSION

Serum procalcitonin is an interesting parameter in the emergency department for management of meningitis suspicion in adults.

An outbreak due to echovirus type 30 in a neonatal unit in France in 1997: usefulness of PCR diagnosis

Between February and August 1997, 53 patients with enterovirus meningitis were hospitalized in Clermont-Ferrand, France. All but one were children. Echovirus type 30 was involved in 70% of cases with identified serotype. The outbreak ceased on August 8. Two months later, a neonate was admitted to the neonatal unit with an echovirus type 30 meningitis thought to be acquired at delivery. Twenty days later a nosocomial outbreak of echovirus type 30 involving five neonates occurred. Two of them presented with meningitis and two with febrile seizure; One was asymptomatic. The retrospective examination of the maternal sera in a neutralization test, using the index case strain as a source of antigen, showed that none of the neonates was passively immunized before hospitalization. The use of genome detection in cerebrospinal fluid allowed rapid diagnosis and infection was contained by re-inforcing hygiene measures. Prospective examination of stools in the neonatal and paediatric units showed no further occurrences of the disease. No sporadic case was observed in the general population. Hence, nosocomial infections can occur a long time after an outbreak in the general population; rapid diagnosis with molecular tools is useful both for a definite diagnosis in patients already hospitalized, and to act as a rapid alert, even in intervals between seasonal outbreaks.

C-reactive protein is useful in distinguishing Gram stain-negative bacterial meningitis from viral meningitis in children

OBJECTIVE

To clarify to what extent Gram stain-negative bacterial meningitis can be distinguished from viral meningitis by assessment of cerebrospinal fluid (CSF) and blood indices and serum C-reactive protein (CRP) in children over 3 months of age.

DESIGN

Common CSF indices, blood leukocyte counts, and serum CRP values were compared between patients with bacterial meningitis who had a positive CSF bacterial culture but a negative Gram stain and patients with viral meningitis.

POPULATION

Three hundred twenty-five consecutive patients with CSF culture-proven bacterial meningitis, for whom Gram stain was negative in 55 cases, and 182 children with proven or presumed viral meningitis.

RESULTS

Significant differences between patients with bacterial and viral meningitis were found in all indices with large overlap in all except serum CRP. In patients with bacterial meningitis, the mean CSF glucose concentration, protein concentration, leukocyte count, blood leukocyte count, and serum CRP were 2.9 mmol/L (52 mg/dL), 1.88 g/L, 4540 x 10(6)/L, 18.0 x 10(9)/L, and 115 mg/L; and in those with viral meningitis, mean values were 3.3 mmol/L (59 mg/dL), 0.52 g/L, 240 x 10(6)/L, 10.6 x 10(9)/L, and <20 mg/L, respectively. Of the tests investigated in this study, only serum CRP was capable of distinguishing Gram stain-negative bacterial meningitis from viral meningitis on admission with high sensitivity (96%), high specificity (93%), and high negative predictive value (99%).

CONCLUSION

Exclusion of bacterial meningitis with only the conventional tests is difficult. Combined with careful physical examination and CSF analyses, serum CRP measurement affords substantial aid.

[Procalcitonin, a marker of bacterial meningitis in children]

Procalcitonin (PCT) is a new marker connected to systemic bacterial infection. Blood values are parallel to the severity of the disease. In the present Knowledge on PCT, the usefulness is focused on acute pediatric pathology, ICU, and the follow up of grafts and surgery. This paper dwells on the interest in the differential diagnosis for meningitis (viral versus bacterial). At the opposite of CRP and IL6, a very clear cut off for all the cases has been found. The cut off in this study is about 2-3 micrograms/l. PCT, at the difference of cytokines is a very stable molecule in the blood sample. Also a very small quantity of serum (or plasma) 20 microliters is sufficient for one assay. In the future, a point of care assay will be available and should be very interesting in the emergency wards (pediatric or adult ICU). The origin of PCT seems to be--but perhaps not exclusively--mononuclear cells. The absence of an animal model (except monkeys) is actually a difficulty to progress.

[Procalcitonin, C-reactive protein and interleukin 6 in bacterial and viral meningitis in children]

OBJECTIVES

In young children with meningitis, blood or cerebrospinal fluid (CSF) analysis cannot differentiate all cases of viral meningitis (VM) from bacterial meningitis (BM). Empirical antibiotic therapy is often given. As new markers are needed, we compared serum proCalcitonin (PCT) with CSF analysis for C-reactive protein (CRP) and interleukin-6 (IL6).

PATIENTS AND METHODS

PCT was measured with a chemoluminescent assay in the sera of 23 children (aged 3 months to 14 years) hospitalized for BM and in 51 patients with VM.

RESULTS

Initial CRP (mean 143.3 mg/l, range 28-351 and mean 13.9, range 1-48), CSF proteins (mean 2.2, range 0.4-4.74 and mean 0.57, range 0.12-2.72) and white blood cell count in CSF (range 240-17500 and 20-3200) in BM and VM respectively, were not sufficiently discriminative to distinguish between BM and VM. Twenty-four of the 51 patients with VM were given antibiotics. IL6 values at admission showed an overlap zone (> 100 pg/ml in 7/19 patients with VM and < 100 pg/ml in 1/8 patients with BM. PCT was discriminative in all cases: mean PCT in BM was 61 micrograms/l (range 4.8-335) and 0.33 in VM (range 0-1.7; p < 0.001). No production of PCT was detected in CSF. After antibiotic therapy, PCT decreased and reached undetectable levels after recovery.

CONCLUSION

PCT is a sensitive and specific marker for early diagnosis of viral meningitis versus bacterial meningitis in children.

[Beta 2 microglobulin in children with neuroinfections]

CSF and plasma beta2 microglobulin (B2M) concentrations were determined by an enzyme linked fluorescent assay (ELFA) (Vidas-bioMerieux) in children with bacterial (B2M), viral (mumps and enteroviral) meningitis and in the controls. CSF B2M concentrations in children with B2M at admission, at 24-48 hrs of treatment and at recovery (day 10), in children with viral meningitis at admission and at recovery were significantly higher in comparison with the control group of children with non-pleiocytic CSF. The levels of CSF B2M at 24-48 hrs of treatment of B2M cases were significantly higher than those at the beginning of both mumps and enteroviral meningitis cases which may be helpful in differential diagnosis of meningitis, especially in cases of retarded diagnosis or partially treated B2M. Plasma levels of B2M during bacterial and mumps meningitis did not differ from those in healthy children but in children with enteroviral meningitis were significantly higher. There was a positive correlation between CSF B2M at the beginning of B2M and some laboratory findings of inflammatory response (CRP, ERS). The CSF B2M levels were significantly higher than its plasma levels in patients with B2M at 24-48 hours (second stage) of disease, mumps meningitis on admission and recovery which may suggest intrathecal production of B2M during central nervous system infection.

[Hypouricemia in patients with meningitis]

Serum urate and sodium concentrations were measured in 23 patients with acute viral and bacterial meningitis. Serum urate level was 3.0 +/- 0.2 mg/dl (mean +/- S.D.) (3.6 +/- 1.2 mg/dl in male and 2.5 +/- 0.9 mg /dl in female) on admission, but gradually elevated with improvements of meningitis. It turned to 4.8 +/- 0.2 mg/dl after recovery, and the value on admission was significantly lower than that after recovery (p < 0.0001). Serum sodium level was 137.6 +/- 2.9 mEq/l on admission and 139.7 +/- 2.7 mEq/l after recovery; also lower in the former (p < 0.01). These results show that patients develop transient hypouricemia, which may be explained by SIADH (syndrome of inappropriate secretion of ADH), although SIADH is subclinical in most cases of meningitis.

Beta-trace protein concentration in cerebrospinal fluid is decreased in patients with bacterial meningitis

Although meninges represent a major site of biosynthesis, beta-trace protein (beta-trace) has not been studied in the cerebrospinal fluid (CSF) of meningitis patients. We measured beta-trace in lumbar CSF of normal controls (n = 27) and in patients with various neurological diseases (n = 92) by an immunonephelometric assay. The mean concentration of beta-trace in CSF of control patients was 16.6+/-3.6 mg/l. In bacterial meningitis (n = 41), CSF beta-trace was significantly decreased (8.7+/-3.9 mg/l; P< 0.001), whereas in spinal canal stenosis it was elevated (29.2+/-10.3 mg/l; P= 0.002). In viral meningoencephalitis (n = 12), beta-trace CSF concentrations were normal. Beta-trace concentrations remained below the normal range even after curing of bacterial meningitis, and normalisation of CSF leucocytes and blood-CSF barrier function. Beta-trace may be a useful tool for studying the pathophysiology of bacterial meningitis.

Levels of interleukin-6, CRP and alpha 2 macroglobulin in cerebrospinal fluid (CSF) and serum as indicator of blood-CSF barrier damage

We measured the levels of interleukin-6 (IL-6), albumin, C-reactive protein (CRP) and alpha 2 macroglobulin (alpha 2M), all of which have different spectrums of molecular weight, in the cerebrospinal fluid (CSF) and serum in 121 patients to evaluate damage to the blood-cerebrospinal fluid barrier (BCB) in meningitis. There was an extraordinary high level of IL-6 in the CSF when patients had bacterial or viral meningitis, but the level returned to a normal range within a week in almost all of these cases. There were no significant differences in CSF albumin levels among the different disease groups. The CRP level in CSF is considered to correlate with the serum level, and CSF CRP was higher in bacterial meningitis than in viral meningitis, however, CRP in CSF was increased in some of the infectious diseases without meningitis. The alpha 2M in CSF, which tends to be at extraordinarily high levels when there is damage to the BCB, correlated highly with CSF cell counts. CSF IL-6 seemed to be a useful indicator to identify the acute active phase of meningitis. CRP and alpha 2M in CSF are considered to be useful to differentiate bacterial meningitis, bacterial infection without meningitis and viral meningitis. Extraordinarily high levels of alpha 2M, which has a high molecular weight, in CSF is indicative of BCB damage.

Rapid direct diagnosis of mumps meningitis by ELISA capture technique

ELISA capture technique (ELISAc) was carried out using a rabbit hyperimmune serum attached to a solid phase for capturing mumps antigens in cerebrospinal fluid (CSF) in patients with meningitis and/or in supernatants of infected Vero cells. A biotin-labelled rabbit serum prepared from the previous serum was added and the reaction was read by an enzymatic (avidine-peroxidase) reaction by automated reading. The cut-off was calculated in 100 CSFs negative for viruses by conventional diagnosis. The specificity was evaluated in Vero cells infected with 22 CSFs collected from vaccinated children (URABE AM9 attenuated vaccine) who developed meningitis. A guinea pig hyperimmune serum confirmed the specificity. Results in culture correlated with the ELISA capture technique (ELISAc). No cross-reactivity was observed with parainfluenza 1, 2, 3 human reference strains. At least 2.5 ngs of purified mumps proteins were detected corresponding to 10(1.5) infectious particles per ml. ELISAc applied directly to 14 CSFs collected from unvaccinated children with meningitis diagnosed five positive cases, whereas in four cases conventional diagnosis had to be undertaken twice. ELISAc permitted the diagnosis of one additional patient. The test can be carried out in 3 h.

[The value of measuring acute phase protein level in pathologic cases with particular attention to nervous system diseases]

Based on Polish and foreign literature the up-to-date knowledge on usefulness of measurement of the level of acute phase proteins in clinical diagnostics is presented. Acute phase proteins may serve as a quick, preliminary test which indicates bacterial infection or necrotic process. They are good markers of treatment efficacy and infectious (bacterial) complications in patients in a hopeless state or with a chronic disease. In neurological diagnostics they are useful in differentiation of bacterial and viral meningitis.

Measurement of procalcitonin levels in children with bacterial or viral meningitis

We measured the plasma procalcitonin levels in 59 children who were admitted to the hospital because of bacterial or viral meningitis. Eighteen children with acute bacterial meningitis had elevated procalcitonin levels (mean level, 54.5 micrograms/L; range, 4.8-110 micrograms/L). The procalcitonin levels in 41 children with viral meningitis were low (mean level, 0.32 micrograms/L; range, 0-1.7 micrograms/L; P < .0001). Assay of cerebrospinal fluid (CSF) cells and proteins and serum C-reactive protein showed a zone of overlapping values between the two groups. Procalcitonin was not produced in CSF. Plasma procalcitonin levels decreased rapidly during antibiotic therapy. These data suggest that the measurement of plasma procalcitonin might be of value in the differential diagnosis of meningitis due to either bacteria or viruses.

Chemokines in the cerebrospinal fluid of patients with meningitis

Meningitis is accompanied by a differential immigration of leukocytes into the subarachnoid space. Since the mechanisms regulating leukocyte invasion are still incompletely understood, we studied the release of the neutrophil-attracting alpha-chemokines IL-8 and GRO-alpha and the mononuclear cell-attracting beta-chemokines MCP-1, MIP-1alpha, and RANTES during meningitis. In 48 paired CSF and serum samples from patients hospitalized for meningitic symptoms, high levels of IL-8, GRO-alpha, and MCP-1 were detected in the CSF during bacterial and abacterial meningitis. Elevated chemokine levels were not found in the blood serum samples taken in parallel. The release of MIP-1alpha or RANTES was below detection limits. The IL-8 and GRO-alpha levels significantly correlated with the number of immigrated granulocytes in the CSF of patients with bacterial meningitis. A similar correlation was found when MCP-1 levels and the mononuclear cell count were analyzed in abacterial meningitis. These findings suggest that the local production of the alpha-chemokines IL-8 and GRO-alpha and of the beta-chemokine MCP-1 represents the major chemoattractant stimulus for the differential recruitment of leukocytes into the subarachnoid space during meningitis.

Hypozincaemia in febrile convulsion

To understand further the role role of trace elements in pathogenesis of febrile convulsions, serum zinc (Zn), copper (Cu), magnesium (Mg) and CSF An, Cu, Mg and protein levels were measured by spectrometry in patients with febrile convulsion (n = 19), bacterial meningitis (n = 9), viral CNS infection (n = 16) and in the control group (n = 10) which consisted of children with signs of meningeal irritation due to upper respiratory tract infection but normal CSF findings. Samples were obtained within 6 h after admission to hospital. Mean serum and CSF Zn levels in the febrile convulsion group were significantly lower than in the other groups (for serum Zn: 0.66 +/- 0.03 mg/1 vs 0.98 +/- 0.07 mg/1, 1.06 +/- 0.08 mg/1, 1.05 +/- 0.09 mg/1 P < 0.05; for CSF Zn: 22.96 +/- 1.62 micrograms/1 vs 75.47 +/- 6.9 micrograms/1, 50.32 +/- 5.235 micrograms/1, 39.85 +/- 2.81 micrograms/1 P < 0.05). A linear relationship was established between serum Zn and CSF Zn levels (P < 0.001). Mean CSF Zn, Cu and protein levels in the bacterial meningitis group were significantly higher than in the other groups (for CSF Cu 63.94 +/- 6.33 micrograms/1 vs 38.77 +/- 2.70 micrograms/1, 35.84 +/- 3.48 micrograms/1, 33.86 +/- 2.88 micrograms/1 P < 0.05; for CSF protein 0.80 +/- 0.12 g/1 vs 0.22 +/- 0.02 g/1, 0.53 +/- 0.08 g/1, 0.19 +/- 0.01 g/1 P < 0.05). In children with meningitis, the elevation of the mean CSF Zn and Cu levels may result from the breakdown of the blood-brain barrier and subsequent leakage of trace elements and protein from serum to CSF. There was no significant difference between the four groups in terms of mean serum Mg and mean CSF Mg levels.

CONCLUSION

Serum and CSF Zn levels are decreased in children with febrile seizures. Zinc deprivation may play a role in the pathogenesis of febrile seizures.

Sensitivity and specificity of mu-capture ELISA for detection of enterovirus IgM

The sensitivity and specificity of an in-house mu-capture enzyme linked immunosorbent assay (ELISA) for enterovirus IgM in routine use was determined by analysing the results of 77 serum samples from 55 enterovirus culture-positive patients with aseptic meningitis and single serum samples from 140 patients with other infections. In addition, sera from 10 laboratory staff pre- and post-polio virus vaccination and 20 rheumatoid factor positive sera were tested for specificity. On testing the first serum specimen received, only 21 of 55 patients (38%) with aseptic meningitis yielded a positive result, rising to 33 of 55 (60%) on testing a second sample, where available. Out of 14 patients from whom multiple serum samples were tested and negative results obtained with the first serum, 12 were positive with the second sample (86%). Only patients with acute hepatitis A produced a significant number of false positives by the enterovirus ELISA (12 out of 20), but the reverse was not true: patients with enterovirus IgM did not produce false positive results in tests for hepatitis A IgM. Excluding samples positive for hepatitis A IgM, the number of non-enterovirus infections correctly reported as negative was 118 out of 120--a specificity of 98%. This test is probably the most useful serological test available at present for diagnosing recent enterovirus infection, although the limited sensitivity needs to be borne in mind.

[Erythrocyte metabolism in meningococcal infection and purulent meningitis]

The red blood cell metabolic parameters ATP, ADP, sigma AN, ATP/ADP, ATP/ATP, energy charge, PAD, 2,3-DPH, Pn were studied in 106 patients with generalized meningococcus infection (GMI) and meningitis of other etiology over their natural history. There was a typical adaptative red blood cell response that featured glycolytic stimulation on hypoxia that ran with impaired red blood cell energy metabolism (RBCEM), negative energy balance. It was the most pronounced at the peak of disease. RBCEM changes occurred in the presence of antioxidative disorders of red blood cells as lowered PAD levels. When early complications, such as shock, brain edema, death developed, there was a high incidence of signs of erythrocytic biochemical disadaptation. The RBCEM changes were associated with the magnitude of cytolysis, i.e. serum AST and AST/ALT levels. The significance of the metabolic changes found in the red blood cells in the pathogenesis and clinical picture of GMI and purulent meningitis is discussed in the paper.

Nested RT-PCR for detection of sandfly fever virus, serotype Toscana, in clinical specimens, with confirmation by nucleotide sequence analysis

A single tube, reverse transcriptase/polymerase chain reaction (RT-PCR) was developed and evaluated for detecting a 400-bp product of the small RNA of sandfly fever virus, serotype Toscana (TOS). For more sensitive detection of genomic TOS RNA, a nested PCR amplifying a 243-bp cDNA within the RT-PCR product was established. Nucleotide sequence analysis of first- and second-round PCR products using the dideoxy cycle sequencing technique confirmed a previously published sequence of the TOS reference strain (ISS. Phl.3). By nested PCR, genomic TOS RNA was amplified from two consecutive sera taken 3 and 7 weeks after the onset of illness in one patient, and from CSF of a second patient obtained at the onset of meningitis. Authenticity of amplified PCR products was confirmed by nucleotide sequence analysis, revealing a sequence identical to the TOS reference strain. RT-PCR and nested PCR are useful for laboratory diagnosis and studies of the molecular epidemiology of TOS infection.