Usefulness of Real-time PCR to Detect Mycobacterium tuberculosis and Nontuberculous Mycobacteria. |
Eun Young Yun, Su Hee Cho, Se Il Go, Jong Ha Baek, You Eun Kim, Jeong Eun Ma, Gi Dong Lee, Yu Ji Cho, Yi Yeong Jeong, Ho Cheol Kim, Jong Deok Lee, Sun Joo Kim, Young Sil Hwang |
1Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea. hochkim@gnu.ac.kr 2Gyeongsang Institute of Health Sciences, Gyeongsang National University, Jinju, Korea. 3Department of Laboratory Medicine, Gyeongsang National University School of Medicine, Jinju, Korea. |
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Abstract |
BACKGROUND The purpose of this study was to evaluate recently developed real-time polymerase chain reaction (PCR) assay kit to detect Mycobacterium tuberculosis (MTB) and nontuberculous mycobacteria (NTM) in respiratory specimens. METHODS: We assessed the positive rate of the real-time PCR assay to detect MTB and NTM in 87 culture-positive specimens (37 sputum, 50 bronchial washing), which were performed real-time PCR by using Real-Q(TM) MTB&NTM Kit from January 2009 to June 2009, at Gyeongsang University Hospital. To compare the efficacy with the TB-PCR assay, we evaluated 63 culture-positive specimens (19 sputum, 44 bronchial washing) for MTB or NTM, which were performed TB-PCR by using ABSOLUTE(TM) MTB II PCR Kit from March 2008 to August 2008. RESULTS: Among 87 specimens tested using real-time PCR, MTB and NTM were cultured in 58 and 29, respectively. The positive rate of real-time PCR assay to detect MTB was 71% (22/31) and 92.6% (25/27) in AFB stain-negative and stain-positive specimens. For NTM, the positive rate of real-time PCR was 11.1% (2/18) and 72.7% (8/11) in AFB stain-negative and stain-positive specimens. Among 63 specimens performed using TB-PCR, MTB and NTM were cultured in 46 and 17, respectively. The positive rate of TB-PCR was 61.7% (21/34) and 100% (12/12) in AFB stain-negative and stain-positive specimens. TB-PCR was negative in all NTM-cultured 17 specimens. CONCLUSION: TB/NTM real-time PCR assay is useful to differentiate MTB and NTM in AFB stain-positive respiratory specimens and it is as effective in detecting MTB with TB-PCR. |
Key Words:
Mycobacterium tuberculosis, Mycobacteria, Atypical, Polymerase Chain Reaction, Real-Time |
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