Flow sheet of the rpoB PCR-TA cloning-sequencing protocol used to detect and identify M. tuberculosis in joint biopsy samples. If the rpoB PCR result was negative, nested PCR (a) (9), 16S rRNA gene PCR (b) (26), or IS6110 PCR was used for confirmation. c, false positive indicates that nonspecific human DNAs or other unknown sequences were detected; d, the sequences determined were compared to those in GenBank, which confirmed the presence of mutation sites (10). MF-MR, PCR primers.