DIAGNOSTIC PERFORMANCE OF GENE XPERT MTB/RIF ASSAY IN PLEURAL FLUID: AN OBSERVATIONAL STUDY AT TERTIARY CARE CENTER
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Keywords
MTB (Mycobacterium Tuberculosis), Gene Xpert, RIF (Rifampicin), CBNAAT (cartridge based nucleic acid amplification test).
Abstract
INTRODUCTION: Tuberculosis (TB) caused by Mycobacterium tuberculosis is a global health concern. According to Global TB Report 2021, the incidence of tuberculosis was 19,33,381. Late diagnosis and delay in treatment causes increase in mortality and morbidity. A reliable and rapid diagnostic tool is the priority for TB control. WHO has approved Gene Xpert MTB/RIF in December 2010 which is a Cartridge Based Nucleic Acid Amplification Test (CBNAAT). A new automated diagnostic molecular test which is not only sensitive (detects 131 CFU/ml of mycobacterium tuberculosis but also a rapid test (results are available in 2 hours) in comparison to liquid culture which are time consuming and necessitates biosafety procedures and require trained laboratory staff.
OBJECTIVE: To evaluate the diagnostic yield of Gene Xpert MTB/RIF assay in pleural fluid.
MATERIAL AND METHOD: A Cross-Sectional Observational study observational study was done in Department of Microbiology, MLN Medical College, Prayagraj from January 2023 to December 2023. The GeneXpert MTB/RIF (Cepheid, Sunnyvale, CA, USA) was performed on pleural fluid along with detection of presence of Mycobacterium tuberculosis it also detected Rifampicin resistance.
RESULT: This study revealed the mean age of pleural fluid sample patients to be 42.0 years. GeneXpert MTB positivity was observed in 22.7% of pleural fluid samples. The diagnostic performance for pleural fluid samples showed a sensitivity of 89.47%, specificity of 100%, PPV of 100.0%, NPV of 96.55%, and an overall accuracy of 97.3%.
CONCLUSION: The Xpert MTB/RIF assay demonstrates high sensitivity and specificity in detecting Mycobacterium tuberculosis in CSF and pleural fluid samples. Its rapid and accurate diagnostic capabilities is a valuable tool for improving diagnosis of tuberculosis in a resource-limited areas.
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DR. RAJNI CHOUDHARY
Junior Resident, Department of Microbiology, MLNMC, Prayagraj
DR. REENA SACHAN
Associate Professor & Head, Department of Microbiology, MLNMC, Prayagraj
DR. ABHISHEK SINGH
Assistant Professor, Department of Pulmonary Medicine, MLNMC, Prayagraj
DR. GARIMA GAUR
Assistant Professor, Departmet of Microbiology, MLNMC, Prayagraj
DR. KAMLESH SONKER
Assistant Professor, Department of Neurology, MLNMC, Prayagraj
DR. AMITABH DAS SHUKLA
Professor, Department of Pulmonary Medicine, MLNMC, Prayagraj
DR. MANISHA MAURYA
Professor & Head, Department of Paediatrics, MLNMC, Prayagraj