Abstract:

Objective: The aim of this study was to investigate whether an algorithm has been used for the diagnosis of Mycobacterium tuberculosis samples over the last three years. Material and Methods: A total of 1,036 samples collected between June 2010 and March 2013 were submitted to the laboratory for the diagnosis of Mycobacterium tuberculosis. The samples were studied using the Ehrlich-Ziehl-Neelsen (EZN) staining. Various culture methods such as Löwenstein-Jensen (LJ) medium-BacT/ALERT® 3D and the BD BACTEC™ MGIT™ 320 Mycobacteria Culture System were applied for 508 samples. Real-time Polymerase Chain Reaction (PCR) method was performed in 138 samples. In general, 2 or 3 samples were obtained from each patient for the diagnosis of acid-fast bacilli (AFB), whereas only one sample was obtained for culture. Result: Of the EZN-positive samples, 30% were PCR-positive and 65% were culture-positive; of the culture-positive samples, 13% were PCR-positive and 54% were EZN-positive; of the PCR-positive samples, 21% were culture-positive and 43% were EZN-positive. Conclusion: AFB and culture are likely to be inadequate for the determination of Mycobacterium tuberculosis. Therefore, PCR seems to be an essential need. However, the clinical table of the patient should also be considered to determine the need for PCR. Thus, an appropriate algorithm should be suggested for the diagnosis of Mycobacterium tuberculosis.

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