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Limited analyses of cerebrospinal fluid from patients with central nervous system infections have shown that the oligoclonal IgG is antibody directed against the agent that causes disease. Using a new method involving binding of IgG to beads coated with lysates prepared from candidate infectious antigens, we showed that the oligoclonal IgG in cerebrospinal fluid of a patient with chronic varicella zoster virus vasculopathy is directed against the causative virus. This approach holds promise in identifying and purifying the relevant oligoclonal IgGs in inflammatory central nervous system diseases of unknown cause.

Polymerase chain reaction assays are a powerful tool for detecting the presence of infectious genomes in the cerebrospinal fluid. Positive results always mean a current or pending infection of the central nervous system. Subacute (>7 days) or chronic infections induce an intrathecal humoral immune response and the appearance of oligoclonal IgG antibodies directed against the causal infectious agent. This local synthesis may be observed even in cases of severe systemic immunodeficiency. The use of polymerase chain reactions in combination with the detection of a specific intrathecal immune response should represent the most reliable strategy for the diagnosis of viral and chronic infections of the central nervous system. The authors describe their experience, using this approach, in herpetic encephalitis, acute and recurrent herpetic meningitis, varicella zoster-induced neurological diseases, cytomegalovirus encephalitis, progressive multifocal leukoencephalitis and tuberculous meningitis.

An optimized automated IEF procedure in polyacrylamide micro gels and immunofixation with 10 monospecific antibodies against some fragments of the IgG molecule and against the whole IgG isotypes IgG(1), IgG(2), IgG(3), IgG(4), respectively, detected oligoclonal bands (OBs) within acid, neutral, and alkaline ranges of the gels. Accuracy and reliability of the OB assay for detection of an intrathecal IgG synthesis proved to be higher with immunofixation than with silver staining of bands precipitated by trichloroacetic acid. CSF OBs were specified as lambda or kappa IgG subfractions, respectively, duplex IgGs precipitated with anti-lambda, anti-kappa, and anti-Fc antibodies at the same pI. Most of OBs were classified as belonging to either IgG(1), IgG(2), IgG(3), or IgG(4) isotypes in CSF. The IEF procedure additionally allowed the discrimination of both free light chains and possible "free" heavy gamma chain fragments in CSF, when immunofixation was done with monospecific antibodies against both light chains and gamma chain fragments (e.g. anti-F(ab')(2), anti-Fd, anti-Fc, anti-C(H)2). The results pointed out a distinct heterogeneity of the IgG immune response in human CSF. The IEF procedure with extended immunofixation is recommended for completion of the basic laboratory procedures used in neuroimmunology in order to discriminate inflammatory processes in human CNS.

Enterovirus 71 (EV71) infection can lead to devastating clinical outcomes. An appreciation of the scientific relationship between cytokine response and patient mortality may help limit the risks posed by this deadly illness. We present the results of a study that compared the cerebrospinal fluid (CSF) and serum levels of interleukin-6 (IL-6) and interleukin-1beta (IL-1beta) in 24 patients with EV71 infection. Cases in this study involved diverse manifestations or complications, including encephalitis, poliomyelitis-like syndrome, meningitis, and pulmonary edema. CSF levels of IL-6 in study patients were found to be consistently higher during the first 2 days of central nervous system (CNS) involvement than afterward. Compared with patients who did not have pulmonary edema, patients who experienced pulmonary edema had dramatically varied blood values, including IL-6, white blood cell counts, and glucose levels. Our findings suggest that the combination of CNS and systemic inflammatory response may trigger EV71-related cardiopulmonary collapse.

Complete evaluation of cerebrospinal fluid proteinogram represents a routine request of the clinician in the analysis of CSF in the Czech Republic. It comprises the measurement of concentrations of acute phase proteins (CRP, orosomucoid, haptoglobin, transferrin, prealbumin), immunoglobulins (IgG, IgA, IgM), compressive markers (albumin, fibrinogen), markers of CNS tissue destruction (apolipoproteins A-I, A-II, Apo B), complement components (C3, C4), alpha-1-microglobulin, beta-2-microglobulin, and proteinase inhibitors (alpha-1-antitrypsin, antithrombin III). Therefore, 19 CSF proteins of precisely verified clinical relevance are routine parameters for the assessment of the functional state of the blood-CSF barrier, presence of the intrathecal synthesis of immunoglobulins, inflammatory changes and verification of CNS tissue destruction. Evidence of these clinically relevant and independent parameters enabled the detection of the presence of autoimmune and neuroinfective diseases of CNS, even in clinical cases where the basic CSF parameters do not express relevant changes, or they are of a bordering or non-specific character. Clinically typical and the most significant abnormalities in the CSF proteinogram represent themselves a new access to a contemporary CSF analysis. Despite the fact that assessment of CSF proteins and their analysis is quite a difficult field in laboratory medicine, it is now routinely requested and routinely performed in the Czech Republic.

Background: Polymerase chain reaction (PCR) is becoming the new standard for virological diagnosis of the infections of the central nervous system (CNS). Varicella-zoster virus (VZV) has been considered as the leading cause of viral meningitis or encephalitis in Finland, herpes simplex viruses (HSV) and enteroviruses being the next common causative agents., Objectives: To elucidate the roles of viruses in infections of the CNS by use of novel, sensitive time-resolved fluorescence (TRF) PCR assays., Study Design: We have utilized TRF PCR assays for diagnostics of HSV, VZV, human cytomegalovirus (CMV) and enteroviruses in infections of the CNS. When relevant, we have also applied virus culture and CSF IgM antibody determinations to elucidate the involvement of other viruses in the CNS infections. The material consisted of CSF samples from hospitals in Western Finland, submitted for diagnostic testing for CNS viral infections during the years 2000-2001. A total of 922 CSF samples were tested by PCR., Results: The PCR assays yielded the virological diagnosis in 72 cases whereas only 24 samples were positive by virus culture or CSF IgM antibody assays. Enteroviruses were found in 6.8%, VZV in 5.8% and HSV in 4.6% of the studied CSF samples. The virus culture and CSF antibody tests yielded 0.5-3.2% positive findings., Conclusions: The PCR assays of CSF specimens are most effective for the virological diagnosis of CNS infections. In our study, HSV was the most common causative agent, whereas the diagnostic power of TRF-PCR test was highest for enteroviruses.

The authors studied the intrathecal IgM synthesis (ITMS) in paired sera and CSF samples from 65 patients with MS, 28 with CNS infection, 40 with other neurologic diseases and eight control subjects. ITMS was found in 30 patients with MS and in 20 with CNS infection, but not in patients with other neurologic diseases or in control subjects. In infectious samples, the ITMS is likely a primary response. In MS group, it was associated with higher Expanded Disability Status Scale index (p = 0.017).

The questions most often asked of my residents and myself are the following: (1) How do you interpret the cerebrospinal fluid white blood cell count and polymerase chain reaction results when the lumbar puncture has been traumatic? (2) Does the older adult with a serum sample that tests positive by the Venereal Disease Research Laboratory test need spinal fluid analysis for neurosyphilis, and which of those syphilis tests can become nonreactive even though the patient is never treated? (3) Do you give steroids to patients with bacterial meningitis? (4) What do you do for the patient with cryptococcal meningitis who develops a spastic gait? (5) Are all cases of transverse myelitis "idiopathic"? and (6) When does the patient who has had a stroke need spinal fluid analysis to rule out an infectious etiology? This is how we answer these questions.

The laboratory diagnosis of CNS infection is essential for optimal therapy. Acute infection requires rapid turn-around testing with high predictive values, that is, the ability of a test to accurately identify those patients who do or do not have disease caused by a specific etiology. The Gram's stain, fungal stains of direct smears, antigen testing for C. neoformans, and culture of bacteria, fungi, mycobacteria, and some viruses are important tests for the diagnosis of acute infection. The laboratory diagnosis of chronic infection necessitates discussion between the clinician and laboratory technician to allow triaging of testing. Antigen tests for bacteria, fungi, and viruses; antibody tests for multiple microorganisms; and PCR testing for bacteria, M. tuberculosis, and many viruses are all important in limited clinical situations. All testing for acute or chronic disease depends on sufficient specimen that is transported to the laboratory in a manner that will not compromise viability or chemical integrity. Sterile containers that maintain moisture content, exclude oxygen for anaerobic requests, and are stored at proper temperatures (22 degrees C room, 4 degrees C refrigeration, or -20 degrees C freezer depending on pathogen and test) are mandatory. Many laboratory issues addressing the diagnosis of CNS infection are changing or evolving. Most important is the recognition that bacterial antigen testing for the diagnosis of acute bacterial meningitis rarely impacts patient management and is not routinely needed, CSF shunt infections differ from usual meningeal infections and require rapid diagnosis, and TB meningitis remains a difficult disease to diagnosis but may be confirmed first by PCR testing of CSF. In addition, Whipple's disease of the CNS can be confirmed using PCR with CSF; CJD has a marker protein, referred to as 14-3-3 antigen, that can be detected in CSF, and the diagnosis of fungal CNS disease requires careful interpretation of direct smears, antigen and antibody testing, and culture. Most difficult to diagnose among the CNS infections are viral meningitis and encephalitis. The appearance of new etiologies, such as West Nile virus, and the common use of PCR for the herpes viruses and enteroviruses represent important advances. Evolving methods for the laboratory diagnosis of CNS infection represent significant improvements over previous testing; however, the array of tests available demands more attention for appropriate selection, is significantly more expensive, and requires new skills for performance and interpretation. The responsibility for proper use of laboratory testing lies both with the clinician and laboratory technician.

Advances in molecular biology and immunology provide new, highly sensitive and specific techniques that can be applied to analysis of cerebrospinal fluid to enhance the diagnosis and treatment of central nervous system (CNS) infections. In addition to improved accuracy and speed of diagnosis, these modalities may offer improved means of monitoring treatment efficacy, establishing prognosis, detecting organism resistance, and tracking epidemic sources. This brief review discusses a number of recent papers applying these methods, in order to illustrate their value and significance for clinical neurologic practice. Some of these applications are commonly available, whereas others are likely to enter the physician's armamentarium in the near future. As they do, they can be expected to improve the treatment of CNS infections.

HIV-1 infects the central nervous system (CNS) and it has been feared that the CNS may be a sanctuary site where HIV-1 could hide and continue to replicate despite otherwise effective antiretroviral treatment. Neurological HIV-1 related symptoms, cerebrospinal fluid (CSF) viral load, intrathecal immunoactivation and CSF drug concentration measurements are considered in this review of antiretroviral treatment effects on CNS HIV-1 infection. We conclude that antiretroviral combination treatment regimens improve neurocognitive symptoms in HIV-1 infection and substantially lower CSF viral load. The threat of an increasing number of patients with neurological symptoms and continued HIV-1 replication in the brain despite otherwise effective antiretroviral therapy has not yet proved to be a problem. It is, however, important to keep this potential risk in mind, and more longitudinal prospective studies addressing the issue of antiretroviral treatment effects on CNS HIV-1 infection are needed.

Two cases of rotavirus gastroenteritis associated with neurological involvement, one with encephalitis (defined by abnormal neurological signs, cerebrospinal fluid (CSF) pleocytosis and detection of rotavirus genomic nucleic acid in the CSF) and one with a non-inflammatory encephalopathy (defined by abnormal neurological signs, an entirely normal CSF and detection of rotavirus genomic nucleic acid in the CSF), are presented and used as a basis to review and explore potential pathogenetic mechanisms, including direct viral replication within neurons and indirect effects of the newly described rotavirus 'enterotoxin'.

Varicella zoster virus (VZV) is an uncommon but well recognized cause of neurological disease in HIV-infected patients. Analysis of cerebrospinal fluid (CSF) using the polymerase chain reaction (PCR) in HIV-infected patients presenting with neurological disease has increasingly allowed diagnosis of VZV-associated pathology. We report clinical, radiological and virological data from 15 consecutive patients with VZV-associated neurological disease. Clinical presentation was varied, including meningo-encephalitis in 9 and isolated cranial nerve palsies in 6. VZV deoxyribonucleic acid (DNA) was detected by PCR in CSF of 11/15; pleocytosis was present in only 6/15, raised protein in 11/15. Magnetic resonance imaging (MRI) appearances were focal signal abnormalities in 8, meningeal enhancement in 2 and normal in 2. With specific anti-VZV therapy 10 patients recovered fully. The predictive value of PCR on CSF for diagnosis of VZV-associated neurological disease should take into account the patient's clinical presentation, concurrent infections and response to anti-VZV therapy.

Objectives: To ascertain incidence rates of central nervous system infections and provide information for health care planners., Design: A two-stage screening through supervised case referrals and diagnostic evaluation at referral centre to establish a register of CNS infections., Setting: A rural community in the rainforest zone of Nigeria with land area of 186500 m2, average daily temperature of 28 degrees C, annual rainfall of 2080 mm, adult population of 109851 and served by 26 primary, three secondary and twelve comprehensive care facilities. More than two per cent of the populations live in waterlogged areas., Subjects: Adults aged sixteen years and above, constituting incident cases of CNS infections., Main Outcome Measures: Incident CNS infections per 100,000 populations averaged over a two year observational period., Results: Incidence rates were 3.6, 4.1, 2.3, 09, 1.8, 0.9 for acute bacterial meningitis, aseptic meningitis, rabies encephalitis, non-rabies encephalitis, tuberculous meningitis and chronic non-tuberculous meningoencephalitis, respectively. Syphilitic neuroarthropathy had 0.46., Conclusions: Mortality from acute pyogenic meningitis and tuberculous meningitis remained distressingly high. Aseptic meningitis had the highest incidence rate, yet remained inadequately emphasised. Rabies encephalitis was the third commonest cause of CNS infection in the area.

Background: The intraerythrocytic parasite Plasmodium falciparum induces the life-threatening neurologic syndrome of cerebral malaria (CM) from within cerebral blood vessels, without entering the brain parenchyma., Objectives: 1) To assess the use of CSF as an indicator of specific pathologic processes occurring in the brain during CM; 2) to compare this with other neurologic and infectious diseases to understand the distinct pathogenic features of CM; 3) to test the hypothesis that CM involves a specific functional breakdown of the blood-brain barrier (BBB)., Methods: 1) Radial immunodiffusion assays to detect albumin and IgG in matched plasma and CSF samples as indicators of BBB integrity and intrathecal IgG production; and 2) ELISA for soluble intracellular adhesion molecule-1 and sE-selectin, the cytokines tumor necrosis factor-alpha and transforming growth factor-beta1, and the matrix metalloproteinase MMP-9, to detect cellular activation and inflammatory responses within the brain., Results: Albumin and IgG indices implied only minimal degree of BBB breakdown in a few cases of CM, with most remaining within the normal range. In contrast, cryptococcal, tubercular, and acute bacterial meningitis produced detectable changes in the composition of the CSF and evidence of BBB breakdown., Conclusions: CM appears to involve only subtle functional changes in BBB integrity with minimal intraparenchymal inflammatory responses compared with other neurologic infections. This focuses attention on local events within and around the cerebral microvasculature in CM, rather than indicating widespread parenchymal disease.

Diagnosis of central nervous system (CNS) infection with herpes simplex virus (HSV) requires sensitive and rapid techniques. PCR therefore is considered to be the diagnostic gold standard in these cases. However, current PCR protocols are time-consuming and labor-intensive. In addition, the need for post-amplification manipulations increases the risk of laboratory contaminations with amplified products. In order to improve conventional PCR techniques we compared our current semiautomated HSV-PCR-ELISA assay with a new micro-volume rapid-cycle PCR system that combines real-time monitoring and fluorescence melting-curve analysis without the need for post-amplification sample manipulations. Spiking experiments with supernatants of tissue culture-grown HSV type 1 (HSV-1) and type 2 (HSV-2) in HSV-negative control cerebrospinal fluid (CSF) and sterile water revealed that the new rapid cycle PCR protocol is as sensitive and specific as the PCR-ELISA. Furthermore, a mismatch (G:T) within the probe-targeted region of the HSV-2 glycoprotein B gene decreases the probe/product melting temperature (Tm) from 69 degrees C for HSV-1 to 64 degrees C for HSV-2, enabling the simultaneous identification of the two HSV genotypes by melting-curve analysis within one run. This type specificity of the system was confirmed with 30 genital swabs previously analyzed for the presence of HSV-1/2 in cell culture. While our current PCR-ELISA method needs up to 1 day from sample preparation to result generation, the new procedure takes only 1 h. We consider this system as a promising new tool for the analysis of HSV DNA in CSF and in other human body fluids as well as for the diagnosis of other infectious agents where rapid diagnosis, high sensitivity and specificity are required.

This multicentre retrospective study describes the clinical features and prognostic significance of Varicella-zoster virus (VZV)-associated neurological complications. The study was performed in patients with human immunodeficiency virus (HIV) infection, hospitalized for VZV neurological complications, confirmed in every case by positive VZV polymerase chain reaction (PCR) in cerebrospinal fluid (CSF). Between 1990 and 1995, 34 HIV-infected patients were included in the study. At diagnosis, 59% had AIDS, with a median CD4 count of 11 x 10(9)/l. A past history of zoster was noted in 35% of cases. A concomitant herpes zoster rash and/or acute retinal necrosis were noted in 71% and 12% of patients, respectively. The predominant neurological manifestations were encephalitis (13), myelitis (8), radiculitis (7) and meningitis (6). The mean CSF white blood cell count was 126/mm3 and the mean CSF protein concentration was 2.3 g/l. Interferon-alpha level was increased in 36% of patients. VZV was isolated from CSF cultures in 2/6 cases. Magnetic resonance imaging was abnormal, demonstrating encephalitis lesions. After intravenous antiviral therapy, complete recovery was obtained in 18 cases (53%), serious sequelae were observed in 10 cases (29%) and 6 patients died (18%). Severe symptoms and a low CD4 cell count appeared to be associated with death or sequelae. In conclusion, VZV should be considered as a possible cause of encephalitis, myelitis, radiculitis or meningitis in HIV-infected patients, especially in patients with a history of or concomitant herpes zoster or acute retinal necrosis. VZV-PCR in the CSF may allow rapid diagnosis and early specific antiviral treatment.

To evaluate the role of 6 human herpesviruses (cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus-6 (HHV-6), herpes simplex virus (HSV) types 1 and 2 and varicella zoster virus (VZV)) in infections of the nervous system, cerebrospinal fluid (CSF) samples from 662 patients with suspected viral aetiology to neurological symptoms were investigated for presence of herpesviral DNA in a PCR-based study. Of the 69 patients (2 patients had 2 herpesvirus DNA detected in CSF) who had herpesvirus DNA detected in the CSF, 60 (87%) were non-immunocompromised (CMV 7; HHV-6 6; EBV 16; HSV-1 18; HSV-2 9 and VZV 6) and 9 (13%) were immunocompromised (CMV 3; HHV-6 0; EBV 5; HSV-1 0; HSV-2 1 and VZV 0). The study was performed in a retrospective/prospective manner. The HSV-1, HSV-2, VZV and CMV DNA-positive patients usually had typical clinical syndromes, such as encephalitis/myelitis and meningitis, but also other neurological conditions were associated with findings of these viruses. HHV-6 and EBV DNA were detected in patients presenting with a variety of neurological symptoms, and in some of the cases, concurrent with diagnosis of other infections of the central nervous system. Despite the overall variability of clinical conditions seen, a pattern associated with each investigated herpesvirus was discernable as regards clinical presentation.

A case is reported describing a complication of an unsuccessful attempt to aspirate the reservoir of a ventriculoperitoneal shunt system with a suspected shunt infection. This arose due to a misunderstanding of the anatomy of the shunt and resulted in an intracerebral haematoma. The complications of cerebrospinal fluid shunting and the difficulty in the diagnosis thereof are outlined. We discuss the role and method of shunt tapping in diagnosing shunt problems before reviewing the literature describing the rationale. The variation in shunt design is emphasized. Guidelines are then proposed not to dissuade physicians from tapping shunts but to ensure that the procedure is performed safely and in collaboration with neurosurgical units.

Circumstantial evidence suggests that increased apoptosis is responsible for the loss of dopaminergic nigrostriatal neurons in Parkinson's disease (PD). It is impossible to perform high-quality studies on human postmortem material because of the low quality of tissue preservation, and the fact that apoptosis has a duration of only hours, and that the duration of the agonal period itself will lead to massive neuronal cell death. We measured, as epiphenomenon of neuronal cell death ex vivo, the Annexin V concentration in cerebrospinal fluid (CSF) in patients with PD and control subjects. The Annexin V concentration in CSF of patients with PD was significantly lower compared with control subjects. Annexin V concentrations of the CSF did not correlate with dementia, duration of symptoms, age, sex, or treatment of PD. The rationale for measurement of Annexin V in CSF is the fact that Annexin V adheres to dying cells. It is tempting to suppose that the decrease of Annexin V in CSF of PD is the result of consumption of this protein during neuronal apoptosis as has been demonstrated to occur in the midbrain in PD.

The central nervous system (CNS) is susceptible to bacterial, viral, and fungal infections, and prion diseases. Examination of the cerebrospinal fluid (CSF) is crucial in diagnosing these infections. Cerebrospinal tests may directly identify an organism and its nucleic acid and surface constituents by culture, polymerase chain reaction (PCR), or antigen detection. Alternatively, antibody to an organism may be identified in CSF by enzyme-linked immunosorbent assay (ELISA), Western blot, or complement fixation assay. This article discusses how these CSF tests are performed and addresses the sensitivity and specificity of such tests for the diagnosis of selected CNS infections.

Neonatal human immunodeficiency virus (HIV) infection usually occurs intrapartum or postpartum and results in a higher incidence of neurological dysfunction than is seen in adults. To explore the neuropathogenesis of neonatal HIV infection, we infected neonatal macaques with simian immunodeficiency virus (SIV) and followed the course of infection focusing on early time points. Infected neonates had decreased brain growth and mild histological changes in brain that resembled those seen in pediatric AIDS, including perivascular infiltrates of mononuclear cells, mineralization of vessels in the basal ganglia, and gliosis. The perivascular lesions and gliosis were associated with the presence of occasional infected cells that required in situ hybridization with radiolabeled riboprobes for detection. Using this technique, SIV-infected cells were detected in the brain parenchyma within 7 days of infection. These findings were confirmed by nested PCR for SIVgag DNA in brain and RT-PCR for viral RNA in cerebrospinal fluid. Together, these techniques revealed SIV infection of the CNS in 12 of 13 neonates infected with SIVmac239, 3 of 3 infected with SIVmac251, and 2 of 2 infected with SIVmac239/316. The prevalence of CNS infection was indistinguishable from that of older animals infected with the same dose and stock of virus, but neonates appeared to have fewer infected cells in the CNS and detecting them required more sensitive techniques. This observation was true regardless of inoculum and despite the fact that neonates had equal or greater viral loads in the periphery compared with older animals. These data suggest that maturation-dependent host factors have a major impact on the neuropathogenesis of pediatric AIDS.

Polymerase chain reaction (PCR)-based testing of cerebrospinal fluid (CSF) specimens has become standard for confirmatory diagnosis of central nervous system (CNS) infections; however, these tests increase health care costs. We reviewed 3-year data from 974 consecutive CSF specimens submitted for detection of seven pathogens by PCR. In 1997, 237 of 367 specimens (64.6%) were submitted for multiple tests, compared with 203 of 522 (38.9%) in 1996 and 18 of 85 (21.2%) in 1995. In each year the arrival of new house officers coincided with a peak in multiple testing. Among 732 specimens submitted for herpesvirus detection, results were positive for 24 (4.6%) of 523 specimens with increased leukocyte counts or protein levels. None of 209 specimens with normal leukocyte and protein levels were positive for herpesviruses. None of 471 CSF specimens submitted for Borrelia burgdorferi detection were PCR-positive. Use of protein and leukocytes to screen CSF specimens before employing PCR for herpesvirus detection would save almost one-third of costs without reducing sensitivity.

Objective: To assess HIV-1 RNA levels in cerebrospinal fluid (CSF) and their potential correlation with plasma viral load and central nervous system (CNS) HIV-1 infection markers in stable asymptomatic patients with a CD4 T cell count >500x10(6) cells/l., Patients and Methods: Consecutive patients screened for two trials were eligible for lumbar puncture assessment. At day 0, simultaneous samples of CSF and plasma were obtained and levels of total proteins, albumin, IgG, antibodies against HIV-1 p24 antigen, HIV-1 RNA (using the polymerase chain technique) and white cells were measured., Results: The integrity of the blood-brain barrier was preserved (albumin index > or =7) in 59 out of 70 patients (84%). Intrathecal production of antibodies against HIV-1 p24 antigen was demonstrated in 55 out of 70 individuals (78%). Viral load in CSF was significantly lower than plasma values (3.13+/-0.95 versus 4.53+/-0.53, P = 0.0001). HIV-1 RNA was not detected in CSF in only three of the 70 patients (4%). Overall, there was a significant correlation between plasma and CSF HIV-1 RNA levels (r = 0.43, P = 0.0001); however, in 29 patients (41%) there were significant differences (>1.5 log10 copies/ml) between the viral loads in plasma and CSF. In the multivariate analysis, a high level of protein and white cells in CSF, but not the HIV-1 RNA plasma level, were factors independently associated with a higher level of HIV-1 RNA in CSF (P = 0.0001)., Conclusions: HIV-1 RNA can be detected almost always in CSF of asymptomatic patients in early stages of HIV-1 infection including those with a preserved integrity of the blood-brain barrier. The important discrepancies between plasma and CSF viral load, and the independent association between CSF abnormalities and CSF viral load, support the hypothesis of local production of HIV-1.

Background: To compare the diagnosis utility of a reverse transcription-polymerase chain reaction (RT-PCR) for detection of enteroviral RNA in cerebrospinal fluid (CSF) in comparison to viral culture for central nervous system infections in pediatric population and to know the clinic epidemiological characteristics of this infection., Methods: From June to December of 1997, 116 CSF samples of children were included in the study. The samples were inoculated in MRC-5 and HEP-2 and the enterovirus RNA was detected with AMPLICOR-Enterovirus (Roche Diagnostic System). The virus were typed by neutralization., Results: 36 samples were positive (30 were positive for RT-PCR and 6 for RT-PCR and viral culture). The media time in detect the CPE was 4.8 days. The viruses found were four echovirus 6, one echovirus 30 and one echovirus 7. Fifteen children were under 6 months (93.3% under two months) and 21 children over 6 months with a media age of 81 months (range, 38-160 months). In over 6 months old children, the most frequent clinical presentation was meningitis aseptic syndrome with pleocytosis and in under 6 months old ones was fever and only 60% of these children had pleocytosis. The evolution was good in all the cases., Conclusions: AMPLICOR-Enterovirus is a sensitive method for the diagnosis of enteroviral meningitis. The clinical manifestations are different with the age and due to the absence of neurological symptoms and pleocytosis in the patients under two months, we think that it is necessary to study the presence of enterovirus with genetic amplification methods in this population of patients.

Over a 2 year period, we identified five HIV-infected patients who presented with central nervous system infection caused by varicella-zoster virus, three with myelitits, and two with meningoencephalitis. All five patients were profoundly immunocompromised. Clinical presentation of these patients overlapped to a significant extent with diseases caused by other viruses, e.g. CMV. Indeed, in one case, a dual infection with CMV was diagnosed, but the respective role of each virus was ascertained by in situ hybridisation. At the time of CNS involvement, only one patient had active VZV cutaneous lesions, which were instrumental in diagnosing her condition. In contrast, PCR for VZV DNA in the CSF was helpful in making a diagnosis in the four other cases, one of which was confirmed by a post mortem. Of these five patients, two patients developed VZV disease while receiving oral acyclovir and had foscarnet treatment initiated when MRI demonstrated widespread lesions. They did not respond to antiviral therapy. The three other patients had intravenous acyclovir initiated at a time when no or limited parenchymal lesions were observed by MRI. Two of these three patients had VZV infection diagnosed solely on the basis of PCR: all three responded to treatment. Our data show that reactivation of VZV involving the central nervous system occurs frequently in the absence of cutaneous lesions. PCR of cerebrospinal fluid may help in making an early diagnosis which is probably a prerequisite for successful treatment of VZV infection of the CNS.

Enterovirus 71 has been associated with several outbreaks, as well as sporadic cases, of central nervous system infection and has a worldwide distribution. Seven children with encephalitis and five with aseptic meningitis caused by Enterovirus 71 were seen at Otsu Municipal Hospital during the summer of 1997. The infections were confirmed serologically, although detection of the viral genome in cerebrospinal fluid was unsuccessful. Seven children were diagnosed as having hand-foot-and-mouth syndrome, two were diagnosed as having herpangina, and three patients younger than 12 months old developed no eruptions. The skin or mucosal manifestations of this outbreak demonstrated considerable variation. The Enterovirus 71 strain that caused the outbreak had a strong neurovirulent tendency. Among the patients with encephalitis, symptoms originating from the impairment of diencephalon were seen in four patients, and those originating from cerebellar impairment were seen in two patients. Brain magnetic resonance imaging in one patient revealed an abnormality in the pons. The neurologic manifestations associated with Enterovirus 71 infection may be characterized by involvement of the cerebellum, brainstem, and diencephalon. Enterovirus 71 is one of the pathogenic viruses that cause hand-foot-and-mouth syndrome, as well as a variety of other clinical manifestations. The most important of these is neurologic disease, especially in infants and young children.

Central nervous system (CNS) infections caused by bacteria with reduced sensitivity to antibacterials are an increasing worldwide challenge. In successfully treating these infections the following conditions should be considered: (i) Antibacterials do not distribute homogeneously in the central nervous compartments [cerebrospinal fluid (CSF), extracellular space of the nervous tissue, intracellular space of the neurons, glial cells and leucocytes]. Even within the CSF, after intravenous administration, a ventriculo-lumbar concentration gradient is often observed. (ii) Valid parameters of drug entry into the CSF are the CSF: serum concentration ratio in steady state and the CSF: serum ratio of the area under the concentration-time curves (AUCCSF/AUCS). Frequently, the elimination half-life (t1/2 beta) in CSF is longer than t1/2 beta in serum. (iii) For most antibacterials, lipophilicity, molecular weight and serum protein binding determine the drug entry into the CSF and brain tissue. With an intact blood-CSF and blood-brain barrier, the entry of hydrophilic antibacterials (beta-lactam antibacterials, glycopeptides) into the CNS compartments is poor and increases during meningeal inflammation. More lipophilic compounds [metronidazole, quinolones, rifampicin (rifampin) and chloramphenicol] are less dependent on the function of the blood-CSF and blood-brain barrier. (iv) Determination of the minimal inhibitory concentrations (MIC) of the causative organism is necessary for optimisation of treatment. (v) For rapid sterilisation of CSF, drug concentrations of at least 10 times MIC are required. The minimum CSF concentration: MIC ratio ensuring successful therapy is unknown. Strategies to achieve optimum antibacterial concentrations in the presence of minor disturbances of the blood-CSF and blood-brain barrier include, the increased use of low toxicity antibacterials (e.g., beta-lactam antibiotics), the use of moderately lipophilic compounds, and the combination of intravenous and intraventricular administration. Antibacterials which do not interfere with bacterial cell wall synthesis delay and/or decrease the liberation of proinflammatory bacterial products, delay or inhibit tumour necrosis factor release, and may reduce brain oedema in experimental meningitis. Conclusive evidence of the reduction of neuronal damage by this approach, however, is lacking.

A duplex polymerase chain reaction (PCR) assay for DNA from herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) was applied to cerebrospinal fluid (CSF) from 918 human immunodeficiency virus (HIV)-infected patients with neurological symptoms. HSV-1 or HSV-2 (HSV-1/2) DNA was found in 19 patients (2%). For the 258 patients for whom a diagnosis was confirmed at autopsy, the sensitivity and specificity of PCR analysis for the diagnosis of HSV-1/2 encephalitis were 100% and 99.6%, respectively. Three patients with CD4+ cell counts of > or = 170/microL had HSV-1 central nervous system (CNS) infections (two) or HSV-2 meningitis (one). Sixteen patients with CD4+ cell counts of < 40/microL had HSV-1 CNS infections (two) or mixed HSV-1/2 and cytomegalovirus encephalitis (14). The response to antiviral treatment, which was assessed clinically and by CSF PCR analysis, was variable in the patients with the highest CD4+ cell counts and poor in those with more severe immunosuppression. CSF PCR analysis is of value for the diagnosis and follow-up of treatment of HSV-1/2 CNS infections in HIV-infected patients.

The diagnosis of African trypanosomiasis is parasitologic and often can be difficult, especially in patients infected with Trypanosoma brucei gambiense, the cause of West African sleeping sickness. In the United States imported cases of sleeping sickness are rare, and most occur in tourists returning from East African game parks rather than among immigrants. I report here the use of a T. brucei specific PCR assay in a West African immigrant who presented with neurological symptoms more than 12 years after he had last been in Africa. The patient's historical and physical findings, as well as abnormal cerebrospinal fluid (CSF) parameters, suggested a diagnosis of sleeping sickness. The diagnosis was confirmed when the PCR assay demonstrated the presence of parasite DNA in CSF and blood. Several months after curative therapy the CSF continued to be positive by PCR. These findings suggest that the PCR assay may be useful for sensitive and specific diagnosis of sleeping sickness, but that it may not be helpful for assessing the effect of drug treatment.

To facilitate early diagnosis of herpes virus infection of the central nervous system (CNS), a nested polymerase chain reaction (nPCR) assay was developed to test simultaneously for the presence of HSV-1, HSV-2, and HCMV DNA in the cerebrospinal fluid (CSF) of patients with herpetic CNS disease suspected on clinical grounds. The virus type-specific PCR products were differentiated either by agarose gel electrophoresis or by DNA enzyme immunoassay. Using titrated viral stocks as standards, a sensitivity of at least 0.03 infectious units was obtained for HSV-1, HSV-2 and HCMV and no cross-reactions were recorded. Among 178 CSF specimens (171 patients), which were tested under routine conditions, three contained HSV-1 DNA, one contained HSV-2 DNA and one contained HCMV DNA. No double or triple infection was diagnosed. The presence of inhibitors of the Taq DNA polymerase was monitored by spiking aliquots of the above CSF samples with 3 infectious units each of HSV-1 and HSV-2 or HCMV. Whereas none of 93 samples spiked with HSV-1 and HSV-2 contained inhibitors, the PCR reaction was inhibited in three out of 175 samples (1.7%) spiked with HCMV. The complete procedure which requires only 150 microl of CSF is easily completed within 8 h. Through its speed, reliability and sensitivity, this nPCR assay has met the specific criteria of the diagnostic laboratory.

A PCR assay for detection of enterovirus RNA in multiple specimen types from patients with neurological infections was evaluated. Combined PCR assay of cerebrospinal fluid and serum (systemic specimens) was more sensitive than assaying either specimen alone in children but not in adults. Compared with PCR in systemic specimens, detection of enterovirus RNA in throat swabs showed a sensitivity of 62.5% and a specificity of 75.6%.

Objectives: The value of measurements of serum C-reactive protein (CRP) in differentiating central nervous system (CNS) infections of varying etiologies in the Philippines was investigated., Methods: A wide array of bacteriologic and virologic methods as well as computed tomography, typical clinical presentation, and autopsy were used for etiologic diagnosis., Results: Among 103 patients with CNS infection, etiology was identified in 60 (58%) cases. Bacteria were found in 19 (including 7 Streptococcus pneumoniae, 5 Haemophilus influenzae, 3 Neisseria meningitidis), tuberculosis in 4, viruses in 38 (including 20 coxsackievirus, 8 measles, 4 adenovirus, and 4 poliovirus infections), and brain abscess in 3 patients. C-reactive protein was elevated on admission in all 18 cases of bacterial meningitis tested, exceeding 50 mg/L in 17 (94%), and was not affected by prior antibacterial treatment. The mean CRP was significantly higher in the bacterial group than in the viral group (207 +/- 111 mg/L vs. 39 +/- 34 mg/L; P < 0.001). In the viral group one third had CRP above 50 mg/L. In patients with tuberculous meningitis, brain abscess, or cryptococcal meningitis, CRP was moderately to highly elevated., Conclusions: In the presence of a normal CRP concentration (below 10 mg/mL) acute bacterial meningitis is excluded even in a developing country setting and antimicrobial therapy is not warranted.

Neopterin is a sensitive indicator for cellular immune activation. Its concentrations were determined in cerebrospinal fluid (CSF) and serum specimens from 91 children with no evidence of central nervous system (CNS) or peripheral inflammations, 43 with definite neuroborreliosis, 51 with other CNS infections, and 33 with peripheral infections. The aim of our study was (a) to establish a range of normal CSF neopterin concentrations in control children, and (b) to inquire into the diagnostic potential of neopterin measurements in both body compartments for aiding in differential diagnosis of inflammatory vs noninflammatory diseases, and CNS vs peripheral inflammations. CSF neopterin concentrations in controls were invariably low (up to 9.3 nmol/L), but in children with neuroborreliosis and, even more so, with other CNS infections neopterin concentrations were significantly (P <0.0001) increased. Children with peripheral infections, however, rarely showed raised CSF neopterin concentrations. Serum concentrations of neopterin, on the other hand, were not significantly different between controls and children with neuroborreliosis. Although serum concentrations were significantly different between controls and children with other CNS infections, diagnostic efficiency was poor for this comparison. Peripheral infections, in contrast, were associated with significantly higher (P <0.0001) serum neopterin concentrations when compared with controls. A classification tree was constructed on the basis of CSF and serum neopterin concentrations, allowing with high accuracy the discrimination between controls, children with CNS infections, and children with peripheral infections. Thus, on the basis of a comparatively large control group, our data underline the diagnostic validity of neopterin as an aid in differential diagnosis of inflammatory vs noninflammatory diseases, and confirm that CSF neopterin concentrations are not correlated with serum neopterin concentrations, and, therefore, CSF neopterin appears to be produced intrathecally.

Cryptococcosis is one of the most common fungal infections of the central nervous system (CNS) in AIDS patients and meningoencephalitis or meningitis is a frequently observed manifestation. However, systematic studies of cerebrospinal fluid (CSF) composition from AIDS patients with CNS cryptococcosis have been few. CSF samples from 114 HIV seropositive patients whose clinical complaint suggested CNS involvement, were analyzed; 32 samples from patients diagnosed as having neurocryptococcosis (Group 1) and 82 samples from patients with no identified neurological disfunction (Group 2). Based on cytological and biochemical results, two distinct profiles were observed: Normal (Group 1 = 31%, Group 2 = 39%); Abnormal (Group 1 = 69%, Group 2 = 61%). Lymphocytes were the most frequent cells in both groups. Our CSF cytological and biochemical findings showed that in AIDS patients liquoric abnormalities are quite frequent, non-specific and difficult to interpret. In these circumstances a systematic search to identify the etiologic agent using microbiological and/or immunological assays must be routinely performed.