[Effects of reagents used in polymerase chain reaction on sensitivity and specificity of detection of Mycobacterium tuberculosis].

OBJECTIVE: To explore the effects of reagents used in polymerase chain reaction on sensitivity and specificity of detection of mycobacterium tuberculosis. METHODS: 205 tuberculosis and 105 nontuberculosis cases' sputum specimens were examined simultaneously by smear, polymerase chain reaction using three different reagents and culture. RESULTS: The positive rates of Mycobacterium tuberculosis by polymerase chain reaction using three different reagents were 82.4%, 71.7% and 61.0% respectively in 205 tuberculosis cases, while 18.0%, 11.4% and 2.8% respectively in 105 nontuberculosis cases. The differences between the above three different groups was statistically significant (P < 0.005). CONCLUSIONS: The sequences of primers and the length of amplified products of different reagents may be associated with the positive and the false positive rates of Mycobacterium tuberculosis in polymearase chain reaction.