Accuracy of polimerase chain reaction for the diagnosis of pleural tuberculosis.
Trajman A, da Silva Santos Kleiz de Oliveira EF, Bastos ML, Belo Neto E, Silva EM, da Silva Lourenço MC, Kritski A, Oliveira MM.
Respir Med. 2014 Apr 23. pii: S0954-6111(14)00150-4. doi: 10.1016/j.rmed.2014.04.007.
Polymerase chain reaction (PCR)-based techniques to detect Mycobacterium tuberculosis DNA in respiratory specimens have been increasingly used to diagnose pulmonary tuberculosis. Their use in non-respiratory specimens to diagnose extrapulmonary tuberculosis is, however, controversial. In this study, we estimated the accuracy of three in-country commercialized PCR-based diagnostic techniques in pleural fluid samples for the diagnosis of pleural tuberculosis.
Patients underwent thoracenthesis for diagnosis purposes; pleural fluid aliquots were frozen and subsequently submitted to two real time PCR tests (COBAS®TAQMAN®MTB and Xpert®MTB/Rif) and one conventional PCR test (Detect-TB®). Two different reference standards were considered: probable tuberculosis (based on clinical grounds) and confirmed tuberculosis (bacteriologically or histologically).
Ninety-three patients were included, of whom 65 with pleural tuberculosis, 35 of them confirmed. Sensitivities were 29% for COBAS®TAQMAN®MTB, 3% for Xpert®MTB/Rif and 3% for Detect-TB®; specificities were 86%, 100% and 97% respectively, considering confirmed tuberculosis. Considering all cases, sensitivities were 16%, 3% and 2%, and specificities, 86%, 100%, and 97%.
Compared to the 95% sensitivity of adenosine deaminase, the most sensitive test for pleural tuberculosis, the sensitivities of the three PCR-based tests were very low. We conclude that at present, there is no major place for such tests in routine clinical use.
Copyright © 2014 Elsevier Ltd. All rights reserved.
Diagnosis, Nucleic acid amplification techniques, Pleural, Polymerase chain reaction, Tuberculosis