Mycobacterial culture is a confirmatory test to detect M.tuberculosis, but it takes at least 6 weeks to diagnose. PCR is a rapid and sensitive method, but it is known that PCR has a high false positive rate due to contamination, and a high false negative rate due to inhibitors. It is also known that LCR and PCR-Hybridization, recently developed methods, are more specific methods than PCR in terms of detection M.tuberculosis. In this study, we estimated the clinical utility of in house PCR, LCR and PCR-Hybridization for the detection of M.tuberculosis.

We evaluated 75 specimens, upon which M.tuberculosis culture based testing was requested, by PCR LCR, and PCR-Hybridization and compared results. Mycobacterial culture was performed on 3% Ogawa media for 8 weeks, and an in house PCR, LCx Mycobacterium tuberculosis assay kit(Abbott Laboratories, North Chicago, III) and the AMPLICOR M.tuberculosis test kit(Roche Molecular Systems, Inc. Branchburg, NJ, USA).

In the view of the culture results, the sensitivities of the three tests were 40%, 80%, and 100% and their specificities were 98.6%, 94.3%, and 94.3%.

LCR and PCR-Hybridization and rapid and sensitive methods for detecting M.tuberculosis in clinical laboratories.