Ma H, Zhu J, Zhang N
Department of Pathology, Tianjin Medical University, Tianjin 300070.
Zhonghua Jie He He Hu Xi Za Zhi. 1998 Jul;21(7):399-401.
To study the sensitivity and specificity of single-tube nested polymerase chain reaction (SN-PCR) technique in detecting Mycobacterium tuberculosis DNA in paraffin-embedded tissues.
BCG DNA and the paraffin-embedded tissues of 30 cases with typical tuberculous lymphadenitis were examined to detect the IS6110 specific insertion sequences DNA of Mycobacterium tuberculosis complex by general PCR(G-PCR), double-tube nested PCR (DN-PCR) and SN-PCR techniques.
Fifteen fg or more BCG DNA could show positive results by DN-PCR and SN-PCR techniques, while 480 fg by G-PCR method. The positive rates of G-PCR, DN-PCR, and SN-PCR in detecting Mycobacterium tuberculosis DNA in 30 cases with tuberculous lymphadenitis were 43%, 100%, and 100% respectively, all of which were significantly different (P < 0.01) from that of the acid-fast staining method (10%). Significant differences in the positive rates also existed between G-PCR and DN-PCR, G-PCR and SN-PCR (both P < 0.01), while the positive rates of DN-PCR and SN-PCR were found same.
The sensitivities of nested PCR techniques in detecting Mycobacterium tuberculosis are significantly higher than that of G-PCR, whereas the sensitivities as well as the specificities of SN-PCR and DN-PCR are the same. Thus SN-PCR seems more practicable.