DETECTION OF MYCOBACTERIUM TB IN PATIENTS WITH EMPYEMA THORACIS USING NUCLEIC ACID AMPLIFICATION TEST

Abstract

PURPOSE: To determine the utility of Nucleic Acid Amplification Test (GeneXpert MTB/RIF Assay) in the diagnosis of tuberculosis in patients with Empyema thoracis using empyema fluid METHODS: This is a cross-sectional study among patients admitted in Jose B. Lingad Memorial Regional Hospital under Department of Internal Medicine, diagnosed with empyema thoracis. Samples of empyema fluid after chest tube insertion were collected and then sent to the hospital’s Department of Pathology for empyema fluid analysis and GeneXpert assay. RESULTS: In Table, the utility of GeneXpert assay in detecting tuberculosis among patients with empyema thoracis showed higher sensitivity of 91.7% as well as specificity of 100%. Whereby those who are positive on GeneXpert assay have a very high likelihood (infinity estimate) of having tuberculosis. Meanwhile, those with negative result in GeneXpert assay are 0.08 times higher to negative with tuberculosis. Thus, GeneXpert assay demonstrates a clinically acceptable performance in detecting tuberculosis among empyema thoracis cases. CONCLUSIONS: GeneXpert assay is a clinically acceptable tool in detecting tuberculosis among empyema thoracis cases which yielded high sensitivity of 91.7% and specificity of 100%. CLINICAL IMPLICATIONS: Hence, based on the result of this study the use of GeneXpert assay may be a viable option in diagnosing TB among patients presenting with empyema thoracis where available. The use of empyema fluid AFB smear in the detection of tuberculosis cannot be recommended due to its low sensitivity result.