Detection Of Antigen In Cerebrospinal Fluid Research Articles

Diagnostic Yield of Pneumococcal Antigen Detection in Cerebrospinal Fluid for Diagnosis of Pneumococcal Meningitis Among Children in China

To determine the diagnostic accuracy of pneumococcal antigen detection in diagnosis of pneumococcal meningitis in children. Purulent meningitis was diagnosed according to European Society for Clinical Microbiology and Infectious Diseases (ESCMID) guideline between July 2014 and June 2016. Along with a cerebrospinal fluid (CSF) culture, pneumococcal antigen detection in cerebrospinal fluid (CSF) was performed, and further identification of pathogens was done with 16S rDNA-PCR and high-throughput sequencing. CSF samples collected from 184 children (median age of 1.92 mo). CSF culture was used as the gold standard. 46 (25%) had positive results for culture and 10 (5.4%) were pneumococci; 34 (18.5%) were pneumococcal antigen positive. The sensitivity and specificity of pneumococcal antigen detection were 100% (95% CI: 89.4%-100%) and 86.2% (95% CI: 96.4%-99.9%), respectively. 92.3% (12/13) were confirmed by nucleic acid detection to be pneumococci. Pneumococcal antigen detection in CSF has adequate sensitivity and specificity in diagnosing pneumococcal meningitis.

Diagnosis of Herpes Simplex Encephalitis by ELISA Using Antipeptide Antibodies Against Type-Common Epitopes of Glycoprotein B of Herpes Simplex Viruses

Herpes simplex encephalitis (HSE) represents one of the most severe infectious diseases of the central nervous system (CNS). As effective antiviral drugs are available, an early, rapid, and reliable diagnosis has become important. The objective of this article was to develop a sensitive ELISA protocol for herpes simplex viruses (HSV) antigen detection and quantitation by assessing the usefulness of antipeptide antibodies against potential peptides of HSV glycoprotein B (gB). A total of 180 cerebrospinal fluid (CSF) samples of HSE and non-HSE patients were analyzed using a panel of antipeptide antibodies against synthetic peptides of HSV glycoprotein gB. The cases of confirmed and suspected HSE showed 80% and 51% positivity for antipeptide against synthetic peptide QLHDLRF and 77% and 53% positivity for antipeptide against synthetic peptide MKALYPLTT, respectively for the detection of HSV antigen in CSF. The concentration of HSV antigen was found to be higher in confirmed HSE as compared to suspected HSE group and the viral load correlated well with antigen concentration obtained using the two antipeptides in CSF of confirmed HSE group. This is the first article describing the use of antibodies obtained against synthetic peptides derived from HSV in diagnostics of HSE using patients’ CSF samples.

Cryptococcal Meningitis in Senegal: Epidemiology, Laboratory Findings, Therapeutic and Outcome of Cases Diagnosed from 2004 to 2011

Cryptococcal meningitis is one of the most important opportunistic infection and a major contributor to early mortality. In sub-Saharan Africa, particularly in Senegal, prevalence of cryptococcal meningitis remains high. This study aimed to describe the epidemiology, laboratory profile, therapeutic and outcome of cases diagnosed in Dakar. We analyzed the cryptococcosis cases diagnosed at the department of parasitology-mycology in Fann Teaching Hospital in Dakar from 2004 to 2011. The diagnosis was confirmed by culture on Sabouraud's dextrose agar and/or by India ink preparation and/or by cryptococcal antigen detection. The diagnosis methods were assessed by using culture as reference. A total of 106 cases of cryptococcal meningitis were diagnosed. The prevalence of cryptococcal meningitis was 7.8%. The mean age of the patients was 40.17±9.89years. There were slightly more male (53.8%) than female (46.2%) patients; 89.6% were found to be infected with HIV, and the median CD4+ count was 27/mm(3). Approximately 79.5% of the patients had <100 CD4+ lymphocytes/mm(3). India ink staining presented sensitivity at 94.11% and specificity at 100%. Sensitivity and specificity of cryptococcal antigen detection in cerebrospinal fluid were, respectively, 96.96 and 15.78%. The most frequently used antifungal drug was fluconazole (86.7%), and the mortality rate was 62.2% (66 deaths). Early diagnosis is essential to control cryptococcosis, and countries should prioritize widespread and reliable access to rapid diagnostic cryptococcus antigen assays. But it is important to make available conventional methods (India ink and culture) in the maximum of laboratory in regional health facilities.

Correlation Of Cryptococcal Antigen Assay With C-reactive Protein As Serum And Urine Biomarker In Cryptococcal Meningitis: Experience In A Tertiary Hospital

Correlation Of Cryptococcal Antigen Assay With C-reactive Protein As Serum And Urine Biomarker In Cryptococcal Meningitis: Experience In A Tertiary Hospital

Impact of Haemophilus influenzae type b conjugate vaccine on bacterial meningitis in the Dominican Republic

Widespread use of Haemophilus influenzae type b (Hib) vaccines has dramatically reduced the burden of Hib disease throughout the Americas. Few studies have evaluated the impact of Hib vaccination on non-culture-confirmed disease. This study analyzed trends in probable bacterial meningitis before and after the introduction of Hib vaccine in the Dominican Republic and estimated vaccine effectiveness against Hib meningitis. Meningitis cases among children < 5 years of age were identified from admission records of the main pediatric hospital in Santo Domingo during 1998-2004. Laboratory criteria were used to classify meningitis cases with probable bacterial etiology; confirmed cases had positive bacterial culture or antigen detection in cerebrospinal fluid. Cumulative incidence rates of confirmed and probable bacterial meningitis were calculated for children living in the National District. Confirmed cases of Hib meningitis were enrolled in a case-control study with age- and neighborhood-matched control children to calculate vaccine effectiveness. Before vaccine introduction, annual rates of meningitis with probable bacterial etiology were 49 cases per 100 000 children < 5 years old; Hib accounted for 60% of confirmed bacterial cases. During 2002-2004, after vaccine introduction, annual rates of probable bacterial meningitis were 65% lower at 16 cases per 100 000, and Hib accounted for 26% of confirmed cases. Rates of Hib meningitis and probable bacterial meningitis with no determined etiology declined by 13 and 17 cases per 100 000, respectively. Introduction of Hib vaccine substantially reduced the incidence of confirmed and probable bacterial meningitis in the Dominican Republic. The estimated impact of Hib vaccination was twice as great when non-culture-confirmed disease was included.

Utilization of Monoclonal Antibodies for Detection ofPlasmodium falciparumAntigen in Cerebrospinal Fluid of Cerebral Malaria Patients

A uniform protein profile of bands at 34, 43, and 52 kDa was obtained with all the cerebrospinal fluid (CSF) samples of malaria (10 in number) and non-malaria patients (31 in number) by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). An immunoreactive band was observed at 43 kDa in CSF samples of cerebral malaria patients but not in non-malaria cases when tested with rabbit anti-Plasmodium falciparum antibodies by Western blot analysis. Eleven reactive monoclonal antibodies against P. falciparum were stabilized and expanded. Nine monoclonal antibodies were reactive to CSF samples of cerebral malaria and non-malaria and P. falciparum antigen by dot-ELISA and a common immunoreactive band at 43 kDa by Western blot. One clone Cl-2 was reactive at 43 kDa with CSF of the cerebral malaria patients and also in P. falciparum antigen but at 66 kDa with non-malarial CSF samples in Western blot. The other two clones (Cl-6 and 14) reacted with 3/31 (90% specific) and 8/31 (74%) CSF samples of non-malaria patients, respectively. The monoclonal antibody based ELISA reported in the present study using clone-6 can therefore offer another possibility for developing rapid, easy-to-perform, low-cost tests for diagnosis of cerebral malaria in CSF samples. Western blot using clone-2 might be useful for the detection of cerebral malaria antigen in CSF.

Epidemiological and Molecular Characteristics of a Highly Lethal Pneumococcal Meningitis Epidemic in Burkina Faso

Public health and clinical strategies for meningitis epidemics in sub-Saharan Africa usually assume that Neisseria meningitidis infection causes most disease. During 24 months from 2002 to 2005, we collected clinical and laboratory information for suspected acute bacterial meningitis cases from 3 districts in Burkina Faso. Streptococcus pneumoniae was identified by culture, polymerase chain reaction, or antigen detection in cerebrospinal fluid. Pneumococcal genotyping was performed on strains using multilocus variable-number tandem repeat typing and multilocus sequence typing. Samples of cerebrospinal fluid were collected from 1686 persons; 249 (15%) had S. pneumoniae identified (annual incidence, 14 cases per 100,000 persons). Of these patients, 115 (46%) died, making S. pneumoniae the most commonly identified organism and responsible for two-thirds of deaths due to bacterial meningitis. During the meningitis epidemic season, an average of 38 cases of S. pneumoniae infection were identified each month, compared with an average of 8.7 cases during other months. Of 48 pneumococci that were tested, 21 (44%) were identified as serotype 1, and the remaining 27 (56%) were identified as 15 different serogroups and/or serotypes. Both serotype 1 and other serogroups and/or serotypes were seasonal. The genotypes of serotype 1 isolates were closely related but diversified over the study period and were similar to, but not identical to, the predominant genotypes found previously in Ghana. Intervention strategies during the epidemic season in Burkina Faso (and perhaps elsewhere) must now account for pneumococcal meningitis occurring in an epidemic pattern similar to meningococcal meningitis. Although a serotype 1 clone was commonly isolated, over half of the cases were caused by other serogroups and/or serotypes, and genetic diversification increased over a relatively short period.

Development of a sandwich dot–enzyme linked immunosorbent assay for Streptococcuspneumoniae antigen detection in cerebrospinal fluid

A new sandwich dot–enzyme linked immunosorbent assay (sdot–ELISA) was developed using omniserum prepared against different strains of Streptococcus pneumoniae as capture antibody and also as second or revealing antibody after its conjugation with horseradish peroxidase (HRP) for detection of pneumococcal antigen in cerebrospinal fluid (CSF). A total of 103 CSF samples of different categories were screened with newly developed dot–ELISA and results were compared with commercially available latex agglutination (LA) kit. The newly developed sdot–ELISA was more sensitive than LA test and can be used as an alternative diagnostic tool in laboratory and in field conditions. An added advantage of this ELISA system was that it did not require antibodies produced in two different animal species.

Meningitis and pneumonia in Guatemalan children: the importance of Haemophilus influenzae type b and Streptococcus pneumoniae.

To determine the epidemiology of Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae invasive infections in hospitalized Guatemalan children. This is an important issue since Hib vaccine has not been incorporated into the routine immunization program in Guatemala and information from hospital records in 1995 indicated a low incidence of Hib and S. pneumoniae as causes of meningitis and invasive infections. Children who were hospitalized in Guatemala City with clinical signs compatible with bacterial infections were evaluated for evidence of Hib or S. pneumoniae infection. Normally sterile body fluids were cultured, and antigen detection was performed on cerebrospinal fluid (CSF) and pleural fluid. Of 1 203 children 1-59 months of age hospitalized over a 28-month period, 725 of them (60.3%) had a primary diagnosis of pneumonia, 357 (29.7%) of meningitis, 60 (5.0%) of cellulitis, and 61 (5.1%) of sepsis and other conditions. Hib was identified in 20.0% of children with meningitis and S. pneumoniae in 12.9%. The average annual incidence of Hib meningitis was 13.8 cases per 100 000 children under 5 years of age, and 32.4% of meningitides caused by Hib and 58.7% of S. pneumoniae meningitides occurred prior to 6 months of age. Case fatality rates were 14.1%, 37.0%, and 18.0%, respectively, for children with Hib, S. pneumoniae, and culture-negative and antigen-negative meningitis. Prior antibiotic therapy was common and was associated with significant reductions in CSF-culture-positive results for children with other evidence of Hib or S. pneumoniae meningitis. Improvements in case detection, culture methods, and latex agglutination for antigen detection in CSF resulted in identification of Hib and S. pneumoniae as important causes of severe disease in Guatemalan children. Using a cutoff of > 10 white blood cells per cubic millimeter in CSF would improve the sensitivity for detection of bacterial meningitis and help estimate the burden of bacterial meningitis in Guatemala and other developing countries.

COMPARISON OF LATEX AGGLUTINATION AND CO-AGGLUTINATION FOR THE DIAGNOSIS AND PROGNOSIS OF CRYPTOCOCCAL MENINGITIS

Purpose: To compare a commercially available Latex agglutination test and an in house co-agglutination test for the detection of cryptococcal antigen in cases of chronic meningitis. Methods: One hundred and fifty cerebrospinal fluid (CSF) samples from 150 cases of chronic meningitis were tested for the presence of Cryptococcus neoformans by modified India ink, culture and antigen detection by latex agglutination test (LAT) and co-agglutination (Co-A) test. Results: Thirty-nine cases were positive by one or more tests employed. Antigen detection in CSF by LAT and Co-A was found to be most sensitive (94.9%) while culture was the least (25.6%). Of the two antigen detection methods, Co-A was found to be more sensitive than the LAT, the difference being statistically significant. Initial CSF antigen titres did not have any prognostic significance. Conclusions: Co-A for antigen detection is an inexpensive and useful adjunct to direct microscopy and culture for the diagnosis of cryptococcal meningitis, though its usefulness in prognosis needs to be evaluated further.

Pneumococcal antigen detection in cerebrospinal fluid: a comparative study on counter immunoelectrophoresis, latex agglutination and coagglutination

The sensitivity, specificity, accuracy and predictive values of counter immunoelectrophoresis (CIE), latex agglutination (LA) and coagglutination (CoAg) tests were compared for detection of pneumococcal antigen in cerebrospinal fluid (CSF) of patients suspected of meningitis. A total of 95 CSF samples comprising 15 culture proven, 47 clinically suspected but culture negative cases of meningitis and 33 controls were screened by above tests. Among three tests, LA was found to have high sensitivity and moderately high negative predictive value than CIE and CoAg tests. However, CIE had slightly better specificity than LA and CoAg tests. Accuracywise CIE and LA tests were comparable than CoAg test. CIE and LA tests had high positive predictive value than CoAg test.

Inflammatory signs, antibody response and antigen detection in cerebrospinal fluid over the course of neuroborreliosis

CSF and serum specimens were consecutively obtained from three patients with neuroborreliosis (stage I, II and III), CSF protein content, cell counts and differential, IgG index, oligoclonal bands and anti-B. burgdorferi antibodies were measured. Cerebrospinal fluid (CSF) was tested for Borrelia-DNA being present prior to and after antibiotic treatment. While DNA could be identified before ceftriaxone was administered, there were no more amplification products afterwards. The goal of this study was to compare the usefulness of serodiagnostic methods and the detection of Borrelia burgdorferi-DNA in patients with clinically confirmed neuroborreliosis to test the efficiency of antibiotic therapy.

Virological markers in the cerebrospinal fluid from HIV-1-infected individuals

We analysed 127 specimens of cerebrospinal fluid (CSF) from 118 HIV-1-infected individuals at different stages of infection. Intrathecal antibody synthesis was evident in 23 samples tested and was more frequently directed against HIV than against rubella virus, herpes simplex virus, varicella zoster virus or cytomegalovirus. HIV was isolated from only 14% of the 127 CSF specimens, but from 82% of CSF-paired blood samples. HIV antigen was detected in 12% of CSF specimens and 44% of paired plasma samples. Twenty specimens analysed using the polymerase chain reaction (PCR) detected proviral DNA in 75% of CSF specimens. The low rate of virus recovery from CSF was caused by neither the freezing of specimens prior to culture nor therapy. In contrast, virus isolation from CSF was significantly associated with CSF cell count. Virus isolation and antigen detection in CSF were not correlated with either the Centers for Disease Control disease stage or the peripheral CD4+ lymphocyte count, whereas viraemia was significantly associated with a low CD4+ lymphocyte count. Moreover, virus isolation and antigen detection in CSF were not associated with symptoms of subacute HIV encephalitis, suggesting that these markers are not of potential value in the diagnosis of HIV-specific neurologic complications. The value of PCR in this field merits further investigation.

Diagnosis of tuberculous meningitis by enzyme-linked immunosorbent assay to detect mycobacterial antigen and antibody in cerebrospinal fluid

Enzymed-linked immunosorbent assay (ELISA) was used to detect mycobacterial antigen and antimycobacterial antibody in cerebrospinal fluid (CSF) specimens of 50 patients with tuberculous meningitis (TBM) and 50 patients with non-tuberculous neurological diseases (control group). The assay gave no false negative results in 10 culture-positive patients with TBM. Detection of mycobacterial antigen in CSF is more sensitive and specific for the diagnosis of TBM than detection of antibody, ELISA should be considered as one of the alternative methods in the laboratory diagnosis of TBM, particularly in culture-negative patients with TBM.

Bacterial antigen detection in cerebrospinal fluid of patients with meningitis

This study compared the sensitivity and specificity of four test systems in detecting Haemophilus influenzae type b, Neisseria meningitidis , Streptococcus pneumoniae , and gram-negative organisms in cerebrospinal fluid (CSF), versus culture. The tests used on CSF from 155 patients with meningitis were the Phadebact coagglutination (CoA) test, the Directigen latex agglutination (LA) test, counterimmunoelectrophoresis (CIE), and the Limulus amebocyte lysate (LAL) test. The sensitivity for patients with bacterial meningitis was 78% ( 18 23 ) for LA, 78% ( 25 32 ) for CoA, and 67% ( 18 27 ) for CIE for detection of H. influenzae type b; 71% ( 10 14 ) for CoA, 100% ( 6 6 ) for LA, and 50% ( 6 13 ) for CIE in detecting S. pneumoniae ; and 33% ( 1 3 ) for LA and 50% ( 2 4 ) for CIE in detecting N. meningitidis . LAL had a sensitivity of 77% ( 37 48 ) in detecting CSF gram-negative endotoxin. The specificities of those with bacterial meningitis for H. influenzae , S. pneumoniae , and N. meningitidis tested by LA were, respectively, 100% ( 35 35 ), 96% ( 50 52 ), and 100% ( 54 54 ); for H. influenzae and S. pneumoniae using CoA 97% ( 62 64 ) and 96% ( 80 83 ); for H. influenzae , S. pneumoniae , and N. meningitidis using CIE 67% ( 18 27 ), 50% ( 6 12 ), and 50% ( 2 4 ). The specificity of LAL was 86% ( 38 44 ). The detection of bacterial antigen from CSF in patients with meningitis by commercial agglutination tests is more sensitive than CIE and is highly specific.

Antigen detection in cerebrospinal fluid—Pros and cons

Over the past decade, rapid diagnostic techniques for detection of bacterial polysaccharide antigens have been developed and successfully applied in the clinical setting. Currently, countercurrent immunoelectrophoresis, latex particle agglutination, and coagglutination are the techniques most used in microbiology laboratories. Enzyme immunoassays may become more practical in the future. Quantitation of antigen concentration in cerebrospinal fluid provides prognostic information at the time of admission. This review summarizes the advantages, disadvantages, and clinical applications of these techniques.

Detection of Neisseria meningitidis cell envelope antigen by enzyme-linked immunosorbent assay in patients with meningococcal disease

Sera from various populations and cerebrospinal fluid (CSF) from meningitis patients were tested for Neisseria meningitidis cell envelope antigen by an enzyme-linked immunosorbent assay (ELISA) sandwich system. The minimum optical density (OD) for antigen detection in CSF was defined as the mean value obtained with specimens from a group of tuberculous meningitis patients plus two standard deviations. By this criterion, antigen was detected by ELISA in four of five CSF specimens from group A meningococcal meningitis patients. Very high ELISA values were obtained with sera from fulminating cases but control sera and sera obtained from meningococcal meningitis nonfulminating cases could not be clearly differentiated by this technique. The possible reasons for this are discussed. The results of this study show that as little as 15 ng/ml (protein) of cell envelope antigen can be detected by the ELISA sandwich test and suggest that the technique may be of value in clinical diagnosis of meningococcal disease.