[Detection of mycobacterial DNA by polymerase chain reaction method]

All published primers and lysis methods were introduced and briefly reviewed herein. Many different polymerase chain reaction procedures were described for the detection of mycobacteria in sputum. Most of these published methods were not satisfactory to detect mycobacteria in clinical specimens. We established a sensitive method to extract mycobacterial DNA in the sputum. First, we treated sputum with Sputazyme, and then with lysozyme. Then mycobacterial DNA was extracted by phenol extraction, beads disruption, or alkaline SDS extraction method. This lysozyme pre-treatment marked increased the sensitivity of the PCR reaction.