During the study period (July to December 2016) a total of 188 samples (sputum and blood from each person) have been tested in the National Reference Laboratory (NRL) at the Institute of Chest and Respiratory Diseases / Baghdad. These cases are considered as suspected pulmonary tuberculosis. This study for these 188 suspected specimens declare that, 103 (54.78%) cases were positive using direct assay (AFB smear microscopy) and 85 (45.21%) were considered to be negative cases by smear microscopy. Of the 103 TB patients, 88 (85.43%) were represented as new TB cases; the others 15 (14.57%) patients appeared to follow up assessment of the directly observed treatment (DOT) program. Detection of M. tuberculosis by real time PCR GeneXpert showed that among total 188 specimens (Suspected Group), 117(62.23%) of the specimens were positive in GeneXpert from sputum and 71 (37.76%) negative specimens by GeneXpert. This study, declares the percentage of sensitivity, specificity, PPV and NPV of GeneXpert which were 94.11 %, 92.75 %, 95.72 % and 90.14 % respectively. Detection of M. tuberculosis by real time PCR using Realline kit showed that among the total 188 specimens (Suspected Group), 112 (59.57%) of the specimens were positive and 76 (40.4%) negative which detected by Real-Time PCR using Realline Kit. All these samples are sputum. This study showed the percentage of sensitivity, specificity, PPV and NPV of Realline kit were 92.43%, 97.1%, 98.21% and 88.15 % respectively. Detection of M. tuberculosis by real time PCR using MTB Robogene kit showed that among the total 188 specimens (Suspected Group), 111 (59.04%) of the specimens were positive, and 77 (40.95%) negative specimens by using MTB Robogene kit, the samples are sputum. The sensitivity, specificity, PPV and NPV of our study was 87.3%, 89.85%, 93.69% and 80.51% respectively. Detection of M. tuberculosis by real time PCR using MTB- DNA Blood showed that among total 188 specimens (Suspected Group), 59 (31.38%) were positive in PCR and 129 (68.61%) were negative, DNA was extracted directly from blood and then tested in MTB Robogene kit. The present showed the percentage of the sensitivity, specificity, PPV and NPV to be 47.89%, 97.1%, 96.6% and 51.93.

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