Role of Bronchoscopy in Patients with Radiological Evidence of Pulmonary Infection but Negative Sputum Culture: A Cross-Sectional Study at Tertiary care setting in North Haryana, India.

Background: Radiological evidence of pulmonary infections often prompts empirical therapy; however, negative sputum culture results may delay definitive diagnosis and appropriate treatment. This study evaluates the diagnostic yield of bronchoscopy, specifically bronchoalveolar lavage (BAL) in such cases. Methods: A cross-sectional study was conducted over a period of 6 months at Tertiary care setting in North Haryana,India, involving 70 patients with radiological signs suggestive of pulmonary infection but negative sputum cultures. All patients underwent diagnostic flexible bronchoscopy with BAL. BAL samples were subjected to Gram staining, Ziehl-Neelsen staining, KOH mount and aerobic cultures. Results: BAL cultures yielded positive results in 48 out of 70 patients (68.6%), significantly higher than initial sputum culture positivity (0%). Pathogens isolated included Klebsiella pneumoniae (16%), Pseudomonas aeruginosa (14%), Acinetobacter baumannii (11%), and Mycobacterium tuberculosis (10%). Fungal elements were detected in 6 patients (8.5%). Conclusion: Bronchoscopy with BAL significantly enhances pathogen detection in patients with radiological evidence of infection and negative sputum cultures. Incorporating bronchoscopy into diagnostic algorithms can improve clinical outcomes by guiding targeted therapy.