Abstract: Objective To evaluate the clinical application value of sputum smear,culture,polymerasechain reaction(PCR) and bacterium proliferation PCR(BP-PCR) for the detection of Mycobacterium tuberculosis.Method One hundred and twenty-four sputum specimens frompatients with pulmonary tuberculosis,suspicious pulmonary tuberculosis,and non-tuberculosiswere detected for Mycobacterium tuberculosis by four methods,and the Results from four methodswere compared.Results The positive rates for the detection of Mycobacterium tuberculosis were 22.5%,32.2%,54.8%,64.5% and 87.1% in 31 sputums from the patients with pulmonary tuberculosis by smear,culture,PCR,and BP-PCR in 4 or7 days,respectively.The positive rateswere 13.6%,18.6%,28.8%,37.3% and 52.5% in 59 samples from the patients with suspicious pulmonary tuberculosis,respectively.There was a significant difference(P<0.05) among four methods. Of 34 sputum samples from the non-tuberculous patients,all were negative by smear and culture methods,but one was positive(2.9%) by PCR and BP-PCR methods,respectively.The positive rate of BP-PCR for detection of Mycobacterium tuberculosis was significantly higher than that of the PCR,but the false positive rate had no difference.Conclusion The BP-PCR assay hadhigh sensitivity and specificity,and might be used for the diagnosis of pulmonary tuberculosis.

Key words: Pulmonary tuberculosis/diagnosis, Sputum smear, Culture, PCR