PT - JOURNAL ARTICLE AU - Gabriela Carnevale AU - Roberta Sales AU - Francisco Vargas AU - Milena Acencio AU - Evaldo Marchi AU - Leila Antonangelo TI - Influence of pre analytical and analytical variables in extraction, amplification and detection of <em>M. tuberculosis</em> in pleural fluid DP - 2012 Sep 01 TA - European Respiratory Journal PG - P2644 VI - 40 IP - Suppl 56 4099 - http://erj.ersjournals.com/content/40/Suppl_56/P2644.short 4100 - http://erj.ersjournals.com/content/40/Suppl_56/P2644.full SO - Eur Respir J2012 Sep 01; 40 AB - Introduction Pleural tuberculosis (PT) is paucibacillary difficulting M. tuberculosis identification in pleural fluid (PF) cultures. PCR- based tests have been shown to improve and speed up the diagnosis of tuberculosis. Because these tests are validated for respiratory specimens, their use in PF samples remains controversial, since hemorrhage, cells and protein content may influence its performance.Objectives To evaluate if pre analytical and analytical factors may influence the sensitivity of PT diagnosis using real time PCR.Materials and Methods From a PF transudate sample, we simulated in vitro samples with increasing concentrations of cells, erythrocytes and protein in which were inoculated M. tuberculosis in concentrations ranging from 1.5 x 106 to 1.5 x 101 CFU/ mL.Two extraction (Qiagen and Roche) and two detection techniques (Roche and Nanogen) were tested in real time PCR.ResultsView this table:Conclusion PCR tests were capable to detect mycobacteria in PF samples even at low concentrations. Hemorrhage, cells and high protein content did not influence the results. The lower mycobacteria detection was obtained with Nanogen kit, independently of the extraction method.