Rapid Diagnosis and Simultaneous Identification of Tuberculous and Bacterial Meningitis by a Newly Developed Duplex Polymerase Chain Reaction

Abstract

The present study describes the development and evaluation of a duplex polymerase chain reaction (D-PCR) for diagnosis and simultaneous identification of tuberculous meningitis (TBM) and bacterial meningitis (BM) in a single reaction. A D-PCR with primers amplifying portions of the Mycobacterium tuberculosis IS6110 and the eubacteria 16SrDNA sequence in a same reaction mix was developed and tested on DNA extracted from 150 clinical CSF samples from different categories (TBM = 39, BM = 26, control infectious and non-infectious category = 85). The results indicate a clear differentiation between bands for eubacteria and M. tuberculosis with an analytical sensitivity of 10 3 cfu/ml for eubacteria and 10 2 cfu/ml for M. tuberculosis. When evaluated in clinical samples, D-PCR overall diagnosed 100 % confirmed TBM and 100 % confirmed BM cases with overall specificity of 96.5 %. D-PCR can be an effective tool for diagnosis and simultaneous identification of TBM or BM in a single PCR reaction. It saves time, cost, labour and sample amount and help in administration of appropriate antimicrobial therapy.The proposed diagnostic assay would be helpful in correct and rapid management of TBM and BM patients.

Two-Year Follow-up Study of Mycobacterium tuberculosis Antigen-Driven IFN-γ Responses and Macrophage sCD14 Levels After Tuberculosis Contact

“…The higher percentage of converters in the Household TB Contact group might have been a consequence of too short an interval between initial M.tb exposure and IGRA testing. The limited sensitivity of IGRA tests, preventing detection of weak mycobacteria-driven immune responses, justifies the search for new antigens with potent immunostimulatory activity and novel diagnostic methods for rapid identification of M.tb infections, in particular the most dangerous ones such as tuberculous meningitis [26][27][28]. A recent study by Fong et al [29] showed that IGRA conversions in serial testing remained a challenging task for clinicians and that using single cut-off point criteria for IGRA might lead to a significant number of false-positive results and overdiagnosis of LTBI.…”