Comparison between the diagnostic accuracy of Xpert MTB/Rif assay and culture for pleural tuberculosis using tissue biopsy.

Abstract

BackgroundEarly diagnosis of pleural tuberculosis is difficult as it is a paucibacillary disease and a combination of tests is required to diagnose it, which have varied diagnostic accuracy and increase the cost. The aim of this study was to evaluate the diagnostic performance of the Xpert MTB/Rif assay on thoracoscopic pleural biopsy specimens.MethodsA total of 201 patients with exudative pleural effusion and normal lung parenchyma were included in the study. All patients underwent thoracoscopic pleural biopsy under local anaesthesia. Biopsy samples were sent for Xpert MTB/Rif assay and culture, along with histopathology. Chronic granulomatous inflammation on histopathology and response to antituberculous treatment was taken as the reference standard for diagnosis of tuberculous pleurisy.ResultsOf the 198 patients included in the final analysis, 134 had pleural tuberculosis. The sensitivity of the Xpert assay was 52.2% and specificity was 100%, and that of pleural biopsy cultures were 41% and 100% respectively.ConclusionThe sensitivity and specificity of Xpert MTB/Rif assay scores were high, hence escalating the speed of diagnosis and imparting marked impact on patient outcomes. The Xpert MTB/Rif assay is a potential game changer in diagnosing pleural tuberculosis.