Analysis of the utility of transbronchial lung biopsy culture under endobronchial ultrasonography with a guide-sheath

Transbronchial lung biopsy (TBLB) culture is not common in clinical practice, and TBLB culture for patients with mycobacterial disease provide limited value because the diagnostic accuracy of TBLB culture is very low. Recently, bronchoscopic devices have been further developed, such as endobronchial ultrasonography with a guide-sheath (EBUS-GS). Therefore, this study investigated the utility of TBLB culture obtained by using EBUS-GS compared to washing cultures. A total of 31 patients who underwent TBLB culture by using EBUS-GS (GS-TBLB) were collected retrospectively at Fukujuji Hospital from January 2018 to December 2022. The diagnostic accuracies of GS-TBLB culture and bronchial and device washing cultures (namely, washing culture) were compared. The patients comprised 13 individuals with nontuberculous mycobacteriosis, 7 with pulmonary aspergillosis, 6 with lung abscess, and 5 with pulmonary tuberculosis. The diagnostic accuracy of GS-TBLB culture was lower to that of TBLB culture than those of washing culture (n = 11 [35.5%] vs. n = 20 [64.5%], p = 0.016), and there was only one patient with positive GS-TBLB culture results and negative washing culture results. Comparing between patients with mycobacteria and non-mycobacteria, GS-TBLB culture positivity were no significant difference between patients with mycobacteria and non-mycobacteria (n = 6 [33.3%] vs. n = 5 [38.5%], p = 1.000), however, patients with mycobacteria diagnosed by washing culture more than those with non-mycobacteria (n = 15 [83.3%] vs. n = 5 [38.5%], p = 0.021). Our results demonstrate that the utility of TBLB culture for the diagnosis of pulmonary infections might provide limited value even if EBUS-GS is performed and lung tissue is successfully obtained.