Analysis of different primers used in the PCR method: diagnosis of tuberculosis in the state of Amazonas, Brazil

Results: Smear and culture results were negative in 24 samples, as was the PCR. The 19 samples testing smear positive, as well as the isolated strains, were 100% positive on PCR, with the exception of the 89.4% result from PCR with MPB64 primers. In the 38 smear negative and culture positive samples, PCR results were inconsistent. The primers specific for amplifying the 123 bp IS6110 fragment gave the highest positivity (92.1%), diagnostic agreement (0.9143), co-positivity (94.7%) and co-negativity (100%).