Comparison of Pathogenic Bacterial Profiles and Imaging Characteristics in Patients with Simple Bronchiectasis and Bronchiectasis–COPD Overlap Syndrome

This study aimed to examine the distribution of pathogenic bacteria and imaging characteristics in patients with simple bronchiectasis (BE) compared with those with bronchiectasis–COPD overlap syndrome (BCOS) and to assess the correlation between these factors. A total of 121 hospitalized patients with BE were classified into the BE group (without COPD) and the BCOS group (with COPD). A retrospective analysis was conducted to examine the distribution of pathogenic bacteria and imaging characteristics and to explore the correlation between these variables. Of the 121 patients, 72 (59.5%) were classified in the BE group and 49 (40.5%) in the BCOS group. The incidence of gram-negative bacterial infections was higher in the BCOS group, with a significantly increased prevalence of Pseudomonas aeruginosa compared with the BE group. Conversely, mycobacterial infections were more frequently observed in the BE group. Among viral pathogens, influenza A and B viruses were notably more common among patients with BCOS, and these differences were statistically significant ( P < 0.05). Variations in pathogen distribution were also identified ( P < 0.001) in cases where high-resolution computed tomography (HRCT) indicated bronchiectatic lesions in both lungs, when fewer than three lung lobes were affected, in cases of unilateral infectious lesions, and when infectious lesions were present in both lungs. BCOS, a distinct subtype of BE, presents with unique pathogen profiles and more pronounced imaging findings compared with standard bronchiectasis, underscoring the importance of these characteristics, which can help guide doctors in their diagnosis and treatment.