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Background: M. tuberculosis grows slowly and requires several weeks to detect in clinical specimens using standard culture techniques. Messenger RNA is more rapidly destroyed in cells than rRNA or genomic DNA, assays that target mycobacterial mRNA better reflect mycobacterial viability. Therefore we evaluated performance of mRNA for monitoring response to antituberculosis therapy using Real-Time PCR. Methods: Sputum specimens from 29 tuberculosis patients confirmed by positive culture were included in this study. Sputum specimens were collected before therapy, at 1st week, 4th week, 8th week and 16th week after initiating antituberculosis therapy to evaluate acid-fast bacilli (AFB), culture and mRNA level. Results: All 29 specimens were positive for culture and mRNA before initiating tuberculosis chemotherapy. Within 29 samples confirmed by positive culture, only 22 (75.9%) patients were positive by AFB. After 8 and 16 weeks of therapy, 27 (93.1%) and 28 (96.5%) were negative by culture, 26 (89.6%) and 28 (96.5%) were negative results for mRNA, and 15 (51.7%) and 29 (100%) were negative results for AFB. Conclusion: Rapidly decline of mRNA level correlated with rapid culture clearance after anti-tuberculosis therapy.

Background: Random Amplified Polymorphic DNA (RAPD) assay has recently emerged as a genotyping method which is both robust and highly discriminatory for bacterial strain differentiation. However, RAPD assessment for Mycobacterium tuberculosiscomplex (MTC) isolates is still limited. Despite its simplicity and rapidity, conventional RAPD also has low reproducibility due to its sensitivity to several factors. Therefore we studied the feasibility of an RAPD-PCR assay to define the genetic diversity of MTC isolates and to evaluate its reproducibility.Methods:493clinical MTC isolates from the island of Sulawesi in Eastern Indonesia, collected from 2005-2012were subjected to Multiplex RAPD assay using 11 random decamer primers instead of one primer which is common in conventional RAPD. All 11 primers were found to be differentiated and produced specific RAPD profiles. The polymorphic amplicons served as RAPD markers for MTC. The dendrograms, obtained by different primers, showed the discriminatory ability of the primers.Results:Multiplex RAPD-PCR results show that the majority of the isolates from South Sulawesi, Southeast Sulawesi andCentral Sulawesiin eastern region of Indonesia belong to group MT-C (80.7%, 80.0% and 62.6 % respectively) with result reproducibility as high as 100%. Conclusion:Molecular typing with multiplex RAPD-PCR is a powerful approach to show the genetic heterogeneity of MTC isolates. The discrimination power and reproducibility of this multiple loci-based RAPD was higher than conventional fewer loci-targeted RAPD.