PT - JOURNAL ARTICLE AU - Cheol-Hong Kim AU - In-Gyu Hyun TI - A comparison between the efficiency of the Xpert MTB/RIF assay and nested PCR in identifying <em>mycobacterium tuberculosis</em> during routine clinical practice DP - 2014 Sep 01 TA - European Respiratory Journal PG - P2673 VI - 44 IP - Suppl 58 4099 - http://erj.ersjournals.com/content/44/Suppl_58/P2673.short 4100 - http://erj.ersjournals.com/content/44/Suppl_58/P2673.full SO - Eur Respir J2014 Sep 01; 44 AB - Background: Polymerase chain reaction (PCR) for the detection of Mycobacterium tuberculosis (MTB) is more sensitive, specific, and rapid than acid-fast bacilli (AFB) smear and culture. The aim of this study was to determine if the Xpert MTB/rifampicin (RIF) assay had additional advantages over nested PCR for the detection of MTB in an area with intermediate tuberculosis (TB) incidence.Methods: The Xpert MTB/RIF assay and MTB nested PCR, as well as AFB smear and culture, were simultaneously performed on 198 clinical samples collected from 171 patients hospitalized for possible TB. The accuracy of the diagnosis of MTB culture-positive TB and the turnaround time of reporting laboratory results were calculated and compared. Rifampin resistance by the Xpert MTB/RIF assay was reviewed with that of conventional drug susceptibility testing (DST).Results: The sensitivity, specificity, and positive and negative predictive values of the Xpert MTB/RIF assay and MTB nested PCR for diagnosis of MTB culture-positive pulmonary TB were 86.1% vs. 69.4%, 97.8% vs. 94.1%, 91.2% vs. 75.8%, and 96.4% vs. 92.0%, respectively. The median turnaround times of the Xpert MTB/RIF assay and MTB nested PCR were 0 (0–4) days and 4 (1–11) days, respectively (P &lt; 0.001). Two cases of rifampin resistance, as determined by the Xpert MTB/RIF assay, were found to be multi-drug resistant pulmonary TB by DST.Conclusions: The Xpert MTB/RIF assay seemed to be sensitive, specific, and comparable to nested PCR for identifying MTB among clinically suspected TB patients, and the assay can be valuable in giving a timely identification of resistance to rifampin.