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Lipoarabinomanan (LAM) antigen which is secreted actively by Mycobacteria at the diseased site and in urine of the infected patient serves as an attractive biomarker to diagnose Tuberculosis (TB). Given the limitations of current diagnostic modalities for Pleural TB which the second most common form of extrapulmonary TB in India, current study evaluated LAM's potential to serve as a point-of-care test to diagnose pleural TB. A pleural fluid specimen was subjected to LAM antigen detection using the lateral flow assay (LAM-LFA; make - Alere/Abott diagnostics) in addition to biochemical and microbiological assays, in a cross-sectional study on suspected pleural TB patients attending a tertiary care hospital in Chhattisgarh, India. The LAM-LFA test was also performed on an early morning urine sample from the same patient. LAM-LFA results were compared to microbiological reference standards/MRS (defined as Pleural TB confirmed by Mycobacterial culture or CBNAAT) and composite reference standards/CRS (Definite plus Probable TB – Clinico-radiologically diagnosed). Out of 170 evaluable subjects, 26 had Definite TB, 22 had Probable TB, and 122 had No TB. When compared to MRS and CRS, pleural LAM-LFA testing was found to be less sensitive (61.54% & 45.83%) with poor PPV (57.14% & 78.57%) but more specific (91.67% & 95.08%) with good NPV (92.96% & 81.69%). Except for having higher specificity (97.2% and 98.3%, respectively, against MRS and CRS), urinary LAM-LFA performed worse than pleural LAM-LFA. When the subgroup of patients with significant ADA levels (ROC derived cut off value = 40 IU/ml) was studied, the specificity and PPV of pleural LAM detection increased to 100% each. Detection of LAM antigen by LFA directly from pleural fluid performed fairly accurate in diagnosing pleural TB and was highly predictive of the disease in a selected cohort of patients making it a valuable POCT. [ABSTRACT FROM AUTHOR]