Clinical efficacy of flexible bronchoscopy with bronchoalveolar lavage and tNGS analysis for diagnosing active pulmonary tuberculosis

Pulmonary tuberculosis remains a leading infectious disease globally, with traditional diagnostic methods demonstrating significant limitations including poor sensitivity and prolonged diagnostic timeframes, particularly problematic for smear-negative tuberculosis cases. Targeted next-generation sequencing (tNGS) combined with flexible bronchoscopy represents an innovative diagnostic approach that may address these diagnostic challenges through enhanced pathogen detection capabilities. A retrospective cohort study was conducted at Guiyang Public Health Treatment Center between January 2021 and December 2023, enrolling 150 patients with suspected pulmonary tuberculosis. Participants were divided into conventional diagnosis group (n=71) receiving standard diagnostic procedures (sputum smear microscopy, GeneXpert MTB/RIF testing, mycobacterial culture) and bronchoscopy-tNGS group (n=79) receiving conventional testing plus flexible bronchoscopy with bronchoalveolar lavage for targeted next-generation sequencing analysis. Primary outcome measure was diagnostic yield, with secondary endpoints including diagnostic accuracy, time to diagnosis, clinical outcomes, respiratory parameters, inflammatory biomarkers, and safety profile. The bronchoscopy-tNGS group demonstrated significantly superior diagnostic performance with higher diagnostic yield (84.8% vs 71.8%, p=0.040), improved diagnostic accuracy (87.3% vs 76.1%, p=0.045), enhanced sensitivity (92.0% vs 78.0%, p=0.020), and better specificity (90.0% vs 76.0%, p=0.033) compared to conventional methods. Time efficiency was markedly improved, with reduced time to diagnosis (5.2±1.5 vs 7.4±2.0 days, p<0.001), shorter sampling-to-result intervals (1.4±0.9 vs 3.8±1.5 days, p<0.001), and decreased hospital length of stay (12.3±4.5 vs 15.6±5.0 days, p=0.001). Clinical outcomes favored the bronchoscopy-tNGS approach, including higher treatment initiation rates (89.9% vs 77.5%, p=0.034), better 90-day favorable clinical responses (85.0% vs 68.0%, p=0.017), reduced empirical treatment rates (6.0% vs 22.0%, p=0.005), and improved respiratory function parameters. Safety analysis revealed a superior profile with lower overall adverse event rates (15.0% vs 25.0%, p=0.038) and reduced treatment-related complications. Integration of flexible bronchoscopy with bronchoalveolar lavage and targeted next-generation sequencing provides superior diagnostic performance for pulmonary tuberculosis detection compared to conventional methods.