Molecular genetic and traditional methods for detection of Mycobacterium tuberculosis complex (discrepancy analysis)

In the past six and half years, 862 different clinical samples [sputum, bronchoalveolar lavage, thorax puncture, cerebrospinal fluid and skin samples] were tested by Gen-probe amplified Mycobacterium tuberculosis direct test (MTD) or ligase chain reaction (LCR) or polymerase chain reaction (PCR). 239 parallel clinical samples were cultivated, and some samples were stained with Ziehl-Neelsen staining. 1-4 samples were tested per patient. 29 (12.13%) samples were positive and 177 (74.05%) samples were negative with both cultivation and molecular genetic methods. 2 (0.83%) samples were positive only on cultivation, and 31 (12.97%) samples were positive only with the molecular diagnostic methods. The differences are undoubtedly explained by the sensitivity of the molecular diagnostic methods.