Using polymerase chain reaction with primers based on the plcB-plcC intergenic region to detect Mycobacterium tuberculosis in clinical samples.
OBJECTIVE
To develop a system for the molecular diagnosis of tuberculosis by polymerase chain reaction (PCR), constructing primers based on the difference in gene organization of the intergenic region of phospholipase C (plcB-plcC region), which differentiates Mycobacterium tuberculosis from other mycobacteria.


METHODS
A PCR product of the expected size (432 bp) was obtained from M. tuberculosis and M. africanum only. A total of 33 mycobacterial isolates and 273 clinical samples from patients suspected of having tuberculosis were examined. These were used in the comparative study of the PCR technique versus culture.


RESULTS
For PCR versus culture, the data showed 93.8% accuracy (p < 0.0001), 93.1% sensitivity (CI: 88.7-96.0), and 96.4% specificity (CI: 96.1-99.4). The Kappa value (0.82) shows that there was a near-perfect concordance between the two tests.


CONCLUSIONS
The use of the plcB-plcC region in PCR amplification was found to be an important and reliable tool for the specific diagnosis of tuberculosis in the samples analyzed.
Pinto
Hermides
H
Amplicon, Porto Alegre, RS, Brasil.
Bica
Claudia Giuliano
CG
Palaci
Moisés
M
Dietze
Reynaldo
R
Basso
Luiz Augusto
LA
Santos
Diógenes Santiago
DS
D016009:Chi-Square Distribution; D017931:DNA Primers / Q000737:chemistry*; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000379:methods*; D011237:Predictive Value of Tests; D017422:Sequence Analysis, DNA; D014376:Tuberculosis / Q000175:diagnosis* / Q000235:genetics / Q000382:microbiology; D010738:Type C Phospholipases / Q000235:genetics
D017931:DNA Primers; D010738:Type C Phospholipases