Diagnostic Value Of Cerebrospinal Fluid Detection For Tuberculous Meningitis

Background: Tuberculous meningitis is a nonsuppurative inflammation caused bytubercle bacillus. Unstandard treatment, appearance of multidrug resistent tuberclebacillus, and increased immuno-deficient patients cause increased incidence of thisdisease and the presentation becomes more and more untypical. All of these make thediagnosis difficult. Tuberculous meningitis is one of the most serious extrapulmonarytuberculosis. Patient’s condition usually become more and more serious if treatmentcould’t be applied promptly, and that will cause CNS functional impairments, or evenmake threat to life. However, there is no good method of high sensitivity and specificitytoward early diagnosis of this disease. So, we are in badly need of a good methodrecently.Objective: To find out a good method for diagnosis of tuberculous meningitis.Methods: The first portion, etiologic diagnosis: To chose36cases of tuberculousmeningitis,57cases of non-tuberculous meningitis. Make analysis of risk factors andclinical presentation toward tuberculous meningitis. To detect early secrectory antigetictarget-6(ESAT-6) and culture filtrate protein-10(CFP-10) in cerebrospinal fluid byenzymelinked immunosorbent assay (ELISA); detect DNA of tubercle bacillus incerebrospinal fluid by fluorescent quantitative polymerase chain reaction (FQ-PCR);detect tubercle bacillus in cerebrospinal fluid by smear method; make comparativeanalysis of these methods. The second portion, quantitive diagnosis: To chose36casesof tuberculous meningitis,24cases of viral meningitis and33cases of noninfectiousneurologic disease. To detect content of interleukin-8(IL-8), matrix metallopeptidase-9(MMP-9) and interferon-gamma (INF-γ) by enzymelinked immunosorbent assay(ELISA), and find out whether there are differences among three groups, and makerelational analysis among three biomarkers.Results: The first portion: Tuberculous meningitis history or having tubeculosis out of CNS is the risk factor of turberculous meningitis by logistic regression. Sensitivity,specificity, positive predictive value and negtive predictive value of ESAT-6detectionby ELISA are33.3%、91.2%、70.6%、68.4%seperately;16.7%、98.2%、85.7%、65.1%seperately, by detecton of CFP-10;19.4%、100%、100%、66.3%seperately, by FQ-PCRmethod;2.8%、100%、100%、61.9%seperately, by smear method. Positive rate oftuberculous meningitis is significantly higher than non-tubeculous meningitis indetection of ESAT-6、CFP-10by ELISA and FQ-PCR method. Positive rate betweentuberculous meningitis and non-tubeculous meningitis has no signigicant difference bysmear method. Sensitivity of ESAT-6detection by ELISA is significantly higher thansmear method. However, sensitivity among other methods aren’t different signigicantly.Specificity, positive predictive value and negtive predictive value among all of thesemethods aren’t different significantly. The second portion: The IL-8, MMP-9and INF-γlevels were significantly higher in the samples from the tuberculous meningitis patientsthan those from either the viral meningitis or noninfectious neurologic diseases. Thecontents of IL-8and MMP-9in patients with viral meningitis were significantly higherthan in noninfectious neurologic diseases. The contents of INF-γ between patients withviral meningitis and noninfectious neurologic diseases aren’t different signigicantly.There are significant relationships between IL-8、MMP-9、INF-γ in cerebrospinal fluid.Conclusion: The first portion: Detection of ESAT-6、CFP-10and FQ-PCR method aremeaningful in diagnosis of tuberculous meningitis, however, smear method is lessmeaningful. The result has great reliability when tuberculous meningitis has been madeby these methods, however, we couldn’t exclude tuberculous meningitis if theconclusion of non-tuberuculous meningitis has been made, and that need to be furtherresearched. The sencond portion: Detection of IL-8, MMP-9and INF-γ in cerebrospinalfluid are useful in diagnosis of tuberculous meningits. Assay of IL-8and MMP-9incerebrospinal fluid are useful in diagnosis of viral meningits too. High concentration ofINF-γ in cerebrospinal fluid is more significant in diagnosis of tuberculous meningitis than IL-8and MMP-9. IL-8, MMP-9and INF-γ are intercoordinated in development ofCNS disease.