Author/Authors :
Du, Jinghui Department of Clinical Laboratory - First Teaching Hospital of Tianjin University of TCM, Tianjin , Liu, Xu Department of Clinical Laboratory - First Teaching Hospital of Tianjin University of TCM, Tianjin , Huang, Zikun Department of Clinical Laboratory - The First Affiliated Hospital of Nanchang University - Nanchang, Jiangxi , Luo, Qing Department of Clinical Laboratory - The First Affiliated Hospital of Nanchang University - Nanchang, Jiangxi , Xu, Xiaomeng Department of Clinical Laboratory - The First Affiliated Hospital of Nanchang University - Nanchang, Jiangxi , Li, Junming Department of Clinical Laboratory - The First Affiliated Hospital of Nanchang University - Nanchang, Jiangxi , Li, Weiting Department of Clinical Laboratory - The First Affiliated Hospital of Nanchang University - Nanchang, Jiangxi , Xiong, Guoliang Department of Clinical Laboratory - The Chest Hospital of Jiangxi Province - Nanchang - Jiangxi 330006, China
Abstract :
Background: Early pleural tuberculosis (TB) diagnosis is particularly difficult. The aim of this study was to investigate the diagnostic
accuracy of the Xpert MTB/RIF (Xpert) (Cepheid, Sunnyvale, CA) assay using pleural biopsy and pleural fluid specimens in patients
with suspected pleural TB but who had a negative sputum acid-fast bacilli (AFB) smear. Materials and Methods: In this study, 134
sputum smear-negative suspected pleural TB patients were selected. Paired pleural fluid and pleural biopsy specimens were tested
for Mycobacterium tuberculosis by standard smear-microscopy, Lowenstein-Jensen and mycobacterial growth indicator tube (MGIT)
culture, and the Xpert assay. Mycobacterial culture from pleural biopsy specimens was used as a reference standard for sensitivity
and specificity calculations. Detection of rifampicin resistance was compared with the MGIT method. Results: Of 126 evaluable
patients, 55 received a diagnosis of pleural TB. The sensitivity of the Xpert assay using pleural biopsy specimens for the diagnosis
of pleural TB was 85.5%, and specificity was 97.2%. The sensitivity and specificity of the Xpert assay in pleural fluid were 43.6% and
98.6%, respectively. The Xpert assay correctly identified 90.0% of phenotypic rifampicin-resistant cases and 93.9% of phenotypic
rifampicin-susceptible cases. Conclusion: The Xpert assay on pleural biopsy specimens may provide an accurate diagnosis of pleural
TB in patients who had a negative AFB smear.
