Diagnostic value and safety of endobronchial ultrasonography with a guide sheath transbronchial biopsy for diagnosing peripheral pulmonary lesions in patients with interstitial lung disease

Background: Radial endobronchial ultrasonography transbronchial biopsy with and without a guide sheath is a useful method for diagnosing peripheral pulmonary lesions (PPLs). However, the diagnostic yield and complications of radial endobronchial ultrasonography transbronchial biopsy for PPLs remains elusive in patients with interstitial lung disease (ILD). Methods: We retrospectively analysed 431 patients (69 with and 362 without ILD) who underwent radial endobronchial ultrasonography with a guide sheath transbronchial biopsy (EBUS-GS TBB) for PPLs from April 1, 2011, to March 31, 2020. We investigated the diagnostic yield and complications of the procedure for PPLs and compared them between patients with and without ILD. We also evaluated the factors contributing to successful diagnosis. Results: The diagnostic yield of radial endobronchial ultrasonography in patients with ILD was significantly lower than in those without ILD (62.3% vs. 75.4%, P=0.024). Multivariate analysis showed that the presence of ILD as background lung [odds ratio (OR) =0.517], probe position within the lesion (OR =4.654), and the presence of solid lesion (OR =1.946) significantly affected the diagnostic yield of PPLs. There was a significant difference in the rate of pneumothorax between the patients with ILD and those without ILD (4.3% vs. 0.6%, P=0.031). Conclusions: The presence of ILD as the background lung significantly affected the diagnostic yield of PPLs with radial EBUS-GS TBB. Regarding the complications, pneumothorax occurred more frequently in patients with ILD than in those without ILD.