Comparison of mNGS microbial detection profiles between percutaneous lung aspiration biopsy and bronchoalveolar lavage fluid in infective pneumonia.

Objectives: To compare the mNGS-based microbial detection profiles of percutaneous lung aspiration biopsy (PLAB) and bronchoalveolar lavage fluid (BALF) in patients with infective pneumonia under real-world clinical sampling strategies. Methods: The study included 166 patients with infective pneumonia, of whom 54 underwent PLAB to obtain unfixed fresh lung tissue from the lesion site, while 112 underwent fiberoptic bronchoscopy to obtain BALF. Results: In the BALF group, 3 pathogens of high concern and 5 suspected pathogens, totaling 8 types of pathogens, were detected. In contrast, in the PLAB group, 1 pathogen of high concern and 1 suspected pathogen, totaling 2 types of pathogens were detected. Cumulatively, 348 pathogens were identified in the BALF group. In the PLAB group, 96 pathogens were identified cumulatively, p<0.001. In the BALF group, the most frequently detected pathogen was Conclusions: BALF and PLAB showed different mNGS microbial detection patterns under different clinical sampling strategies. Because of the retrospective non-paired design, these findings should be interpreted as descriptive comparative data rather than proof of the superior diagnostic performance of either sampling method.